HOST LISTS AND KEYS FOR EACH PLANT GENUS

(in alphabetical order)

Cas-Cha

Cascabela

Casearia

Cassia

Cassinia

Cassytha

Castalia

Castanea

Castanopsis

Castanospermum

Castelleja

Casuarina

Catabrosa

Catalpa

Catamixis

Catananche

Catapodium

Catharanthus

Catharinea

Catimbium

Cattleya

Caucalis

Cayaponia

Cayratia

Ceanothus

Cecropia

Cedrela

Cedrus

Ceiba

Celastrus

Celmisia

Celosia

Celtis

Cenchrus

Cenolophium

Centaurea

Centaurium

Centotheca

Centranthus

Centrosema

Cephalanthera

Cephalanthus

Cephalaria

Cephalanoplos

Cephalotaxus

Cerastium

Cerasus

Ceratocarpus

Ceratocephalus

Ceratochloa

Ceratoides

Ceratonia

Ceratophyllum

Ceratostigma

Ceratotheca

Cercidiphyllum

Cercis

Cercocarpus

Cereus

Cerinthe

Cerinthodes

Ceropegia

Ceropteris

Cestrum

Ceterach

Chaenactis

Chaenomeles

Chaerophyllum

Chaetochloa

Chaetotropis

Chalcas

Chamaebatia

Chamaebatiaria

Chamaecrista

Chamaecyparis

Chamaecytisus

Chamaedaphne

Chamaedorea

Chamaegeron

Chamaemelum

Chamaenerion

Chamaerhodos

Chamaerops

Chamaespartium

Chamaesyce

Chamelaucium

Chamissoa

Chamomilla

Changium

Chaptalia

Chardinia

CascabelaApocynaceae
Cascabela thevetia Aphis gossypii, spiraecola; Myzus persicae

Use key to polyphagous aphids.

Casearia Salicaceae
Casearia arborea Aphis (Toxoptera) aurantii
C. decandra Aphis spiraecola
C. hirsutaAphis (Toxoptera) aurantii
C. sylvestris Aphis (Toxoptera) aurantii
Casearia sp Aphis craccivora

(use key to polyphagous aphids)

CassiaFabaceae
Cassia abbreviata Myzus persicae
C. absus = Chamaecrista absus
C. alata = Senna alata
C. aphylla = Senna aphylla
C. australis (?)Aphis gossypii; Aulacorthum solani; Myzus persicae
C. benitoensis = Senna benitoensis
C. bicapsularis = Senna bicapsularis
C. corymbosa = Senna corymbosa
C. didymobotrya = Senna didymobotrya
C. fistulaAphis craccivora, fabae, odinae; Myzus persicae
C. floribunda (?)Aphis craccivora, fabae, gossypii
C. glauca = Senna sulfurea
C. goratensis = Senna singueana
C. hirsuta = Senna hirsuta
C. hoffmansegi (?)
C. javanicaAphis craccivora
C. laevigata = Senna septemtrionalis
C. leiophylla = Senna leiophylla Aphis gossypii; Myzus persicae
C. leptocarpa = Senna hirsuta var. leptocarpa
C. mimosoides = Chamaecrista mimosoides
C. nomane = Chamaecrista nomane
C. obtusifolia = Senna obtusifolia
C. occidentalis = Senna occidentalis
C. siamea = Senna siamea
C. sophera = Senna sophera
C. sturtiiMyzus persicae
C. surattensis = Senna surattensis
C. tomentosa = Senna hirsuta
C. tora = Senna tora
Cassia sp. (African) Sitobion burundiense

Key to apterae on Cassia:-

SIPH black with polygonal reticulation on distal 0.17-0.25 of length. ANT PT/BASE 5.1-6.6. First tarsal segments all with 4 hairs…..Sitobion burundiense
SIPH if black then without distal reticulation, and other characters do not apply …..go to key to polyphagous aphids
CassiniaAsteraceae
Cassinia quinquefaria Aphis spiraecola
Cassinia sp.Macrosiphum euphorbiae

(use key to polyphagous aphids)

CassythaLauraceae
Cassytha filiformis Sinomegoura citricola
Castalia see NymphaeaNymphaeaceae
Castanea Chestnuts Fagaceae
C. asheiLongistigma caryae; Patchia virginiana
C. bungeanaTuberculatus castanocallis, cereus, ceroerythros, kuricola,
margituberculatus
C. crenataJapanese Chestnut
Cervaphis quercus; Eutrichosiphum pasaniae, pallidum;
Greenidea kuwanai, magna, pallidipes;
[Kurisakia onigurumii]; Lachnus tropicalis;
[Macrosiphum kuricola Matsumura 1917, nomen dubium];
Mollitrichosiphon tenuicorpus; Myzocallis castanicola;
Myzocallis castanicola; Phylloxera castaneivora; Pseudomegoura magnoliae; [Nippolachnus piri];
Tuberculatus capitatus ssp. intermedius, kuricola
C. dentataAmerican Chestnut
Myzocallis castaneae, castaneoides, castanicola;
Patchia virginiana; Phylloxera castaneae
C. formosanaEutrichosiphum tattakanum
C. henryiLachnus tropicalis; Tuberculatus kuricola
C. mollissima[Aphis odinae]; Cervaphis quercus; Greenidea kuwanai;
Lachnus [quercihabitans], tropicalis;
[Metanipponaphis cuspidatae];
Phylloxera castaneae, castaneivora;
Tuberculatus castanocallis, kuricola, margituberculatus
C. nanaMyzocallis castaneoides, nanae, tissoti
C. pubinervisCervaphis quercus; Tuberculatus kuricola
C. pumilaMyzocallis castanicola; Patchia virginiana;
Phylloxera castaneae; Tuberculatus annulatus
C. sativaSweet Chestnut
[Aphis gossypii]; [Aulacorthum solani];
Lachnus longirostris, roboris, tropicalis;
Myzocallis castaneoides, castanicola, castanicola spp.
leclanti, [komareki];
Phylloxera castaneae, [spinifera]; Thelaxes suberi;
Tuberculatus annulatus, kuricola
C. seguiniiTuberculatus castanocallis, ceroerythros
Castanea sp.[Mollitrichosiphum nigrum]

Key to aphids feeding on Castanea:-

1 Antennae 3-segmented (small insect, body pyriform, broadest anteriorly…..2
Antennae 5- or 6-segmented…..3
2 Many dorsal tubercles present on head, thorax and ABD TERG 1-6, decreasing in size and number posteriorly…..Phylloxera castaneivora
Only 4 dorsal tubercles present, confined to head…..Phylloxera castaneae
3 SIPH tubular, several times longer than wide…..4
SIPH truncate or broad, hairy cones…..12
4 Body of aptera with very long, branched, hair-bearing marginal processes (fig. 92A) …..Cervaphis quercus
Body of aptera without hair-bearing processes…..5
5 SIPH without hairs. Antennal tubercles well-developed, approx. parallel-sided in dorsal view (as in fig. 42J) …..Pseudomegoura magnoliae
SIPH with numerous long fine hairs. Antennal tubercles undeveloped…..6
6 SIPH of aptera reticulated either basally or over much of length. Cauda with a distinct median conical papilla (as in fig. 92B)…..7
SIPH of aptera without any reticulation. Cauda without a median papilla …..9
7 SIPH of aptera with a spinulose reticulation over the entire length, except for a small distal part with only spinules . BL 2.4-3.4 mm…..Greenidea magna*
SIPH with reticulation restricted to basal zone. BL 1.3-2.6 mm…..8
8 BL 1.3-2.2 mm. Head and legs mainly pale …..Greenidea (Trichosiphum) pallidipes*
BL 2.0-3.0 mm. Head and legs mainly dark …..Greenidea (Trichosiphum) kuwanai
9 SIPH of aptera more than 0.7 ×BL. Hind tibiae with transverse stridulatory ridges (as in fig. 27A) …..Mollitrichosiphon tenuicorpus
SIPH of aptera less than 0.7 × BL. Hind tibiae without stridulatory ridges …..10
10Dorsum of aptera with numerous irregular transverse rows of minute spinules …..Eutrichosiphum pasaniae
Dorsum of aptera without spinules, or with spinules only on marginal areas of thorax and ABD TERG 1-2…..11
11Antennae of aptera 5- or 6-segmented, of alata 6-segmented. Dorsal abdomen with ill-defined dark pigmentation leaving pale central area on ABD TERG 1-3. SIPH of aptera usually dusky/dark distally…..Eutrichosiphum tattakanum
Antennae 5-segmented in alatae as well as apterae. SIPH of aptera evenly pale, paler than the uniformly smoky dorsal abdomen…..Eutrichosiphum pallidum*
12ANT PT/BASE about 1.0 or more. Anal plate divided by a median cleft into 2 lobes…..13
ANT PT/BASE 0.5 or less. Anal plate not bi-lobed…..26
13 Cauda triangular, apically pointed, without a constriction (fig. 35A). Body and appendages almost entirely brown-black…..Patchia virginiana
Cauda with a constriction and a terminal knob. Body and appendages mainly pale, sometimes with dark markings…..14
14 14 Head and pronotum with a longitudinal dark spinal stripe, and ABD TERG 1-7 each with paired dark dorsal spinal as well as marginal sclerites (fig. 35E). (Wings not maculate) …..15
Head and pronotum without a spinal longitudinal stripe. If ABD TERG 1-7 have a complete set of paired dark dorsal sclerites then wings are strongly maculate…..16
15 R IV with 4-10 accessory hairs. First tarsal segments with 5-6 ventral hairs. Embryos with long hairs (55-70 μm) on ABD TERG 2…..Myzocallis castanicola (s. str.)
R IV with 11-18 accessory hairs. First tarsal segments with 6-8 (usually 7) ventral hairs. Embryos with hairs on ABD TERG 2 shorter (27-41 μm) …..Myzocallis castanicola ssp. leclanti
16Tibiae mainly brown to black, or at least brown on basal half. ANT PT/BASE more than 2.0 …..17
Tibiae mainly pale, sometimes dark apically. ANT PT/BASE less than 2.0 …..20
17Anterior frontal hairs of head long and finely pointed, 2 or more × basal diameter of ANT III (fig.35B)…..18
Anterior frontal hairs less than 2 × basal diameter of ANT III, and sometimes with capitate apices (figs 35C, D)…..19
18 Tibiae and ANT III-VI uniformly black…..Myzocallis castaneae
Tibiae dark at base but with paler middle region. ANT IV, V and BASE VI each pale at base and dark at apex…..Myzocallistissoti
19 Anterior frontal hairs 7-15 um long, shorter than basal diameter of ANT III, and capitate …..Myzocallis nanae
Anterior frontal hairs 30-38 um, longer than basal diameter of ANT III, pointed or slightly capitate (fig. 35D). ANT III-VI and tibiae often completely dark …..Myzocallis castaneoides
20 Forewings with pigment extending between veins, or with veins at least heavily bordered with pigment. Abdomen broad and often with large dark marginal processes …..21
Forewings not pigmented between veins. Abdomen with or without smaller, pale marginal processes…..25
21 ANT III with 4-6 hairs, 1-2 × longer than basal diameter of segment …..Tuberculatus margituberculatus
ANT III with 7 or more hairs, including anteriorly directed long ones that are much more than 2 × basal diameter of the segment…..22
22 ANT III with 16 or more hairs. Marginal processes each with 1-6 transparent noduli (fig. 35F)…..23
ANT III with less than 15 hairs. Marginal processes without any transparent noduli …..24
23Head with 20-22 dorsal hairs. Dorsal body hairs thick, and spinal hairs on posterior tergites arise from tubercular bases…..Tuberculatus ceroerythros*
Head with more than 40 dorsal hairs. Dorsal body hairs thin and spinal hairs on posterior tergites not arising from tubercular bases…..Tuberculatus cereus
24 ABD TERG 2 and 3 each with a pair of quadrate spinal processes, as long as or longer than their basal widths (fig. 35G). Distal parts of hind femora dark…..Tuberculatus castanocallis
Spinal processes on ABD TERG 2 and 3 if developed then rounded, and shorter than their basal widths (fig. 35H). Hind femora pale…..Tuberculatus kuricola
25Spinal processes on ABD TERG 1-3 all similarly developed, finger-like, longer than their basal widths (fig.35I). Anteriorly directed hairs on front of head and ANT I-III long and capitate. SIPH pale…..Tuberculatus capitatus (ssp. intermedius)
Spinal processes only ever well-developed on ABD TERG 3, and then conical, shorter than their basal widths. Hairs on front of head and ANT I-III short or very short, and pointed. SIPH black except at bases…..Tuberculatus annulatus
26 BL less than 2 mm. Antennae 5-segmented. Cauda knobbed …..Thelaxes suberi
BL more than 2.5 mm. Antennae 6-segmented. Cauda broadly rounded …..27
27 ABD TERG 8 unmarked or with only irregular pigment spots. Alata with pterostigma extending around tip of forewing…..Longistigma caryae
ABD TERG 8 with a thin transverse band. Alata with pigmented (maculate) forewings and normal pterostigma…..28
28 Hind tibia with some of more distal hairs on ventral side very long and fine-pointed, at least 2-3 × longer than neighbouring short hairs (fig. 93D). Mesosternal processes always absent or weakly developed. (SIPH cones small and often pale) …..Lachnus longirostris
Hind tibia with hairs on ventral side often longer and finer distally, but not with some hairs 2-3 × longer than others. Mesosternum of summer aptera usually with a pair of mammariform or papilliform processes. (SIPH cones usually large and pigmented) …..29
29ANT/PT BASE 0.40-0.68, usually more than 0.5. Alata with forewing pigmented to base…..Lachnus tropicalis
ANT/PT BASE 0.3-0.5. Alata with clear area at base of forewing …..Lachnus roboris

Castanopsis(= Shiia) Fagaceae
C. acuminatissima Eutrichosiphum pasaniae, pullum;
Greenidea [castanopsidis], magna;
Nipponaphis javanica
C. argenteaEutrichosiphum pasaniae, pullum;
Greenidea magna, pallidipes;
Nipponaphis brevipilosa
C. calathiformis Mollitrichosiphum tenuicorpus
C. carlesiiEutrichosiphum pasaniae; Metanipponaphis ?echinata;
Mollitrichosiphum tenuicorpus
C. cuspidataAllotrichosiphum kashicola;
Eutrichosiphum pasaniae, shiicola, sinense;
Greenidea [kuwanai], okajimai;
Lachnus tropicalis (or shiicola?);
Lithoaphis shiiae; Metanipponaphis cuspidatae, shiicola;
Mollitrichosiphum tenuicorpus; Neonipponaphis shiiae;
[Nipponaphis distyliicola]; Reticulaphis shiiae
C. eyreiNeonipponaphis pustulosa
C. fabriEutrichosiphum pasaniae;
Mollitrichosiphum tenuicorpus, [nigrofasciatum]
C. fargesii[Aphis (Toxoptera) citricidus];
Eutrichosiphum [pseudopasaniae]
C. feroxEutrichosiphum sinense; Mollitrichosiphon tenuicorpus
C. formosanaEutrichosiphum tattakanum; Mollitrichosiphon tenuicorpus
C. hainanensis Mesotrichosiphum pentaiarticulatum
C. hickelii[Allotrichosiphum castanopse (=Eutrichosiphum sinense?)]
C. hystrixMetanipponaphis echinata; Mollitrichosiphon tenuicorpus
C. indicaEutrichosiphum pasaniae, [pseudopasaniae], sinense;
Lachnus acutihirsutus
C. javanicaEutrichosiphum nigrum, pasaniae, sinense;
Greenidea magna, pallidipes; Nipponaphis multisetosa
C. sclerophylla[Eutrichosiphum sclerophyllum (= shiicola?), arunachali ssp.
jianglense];
Lachnus tropicalis; Metanipponaphis lithocarpicola;
Mollitrichosiphum tenuicorpus; [Tuberculatus castanocallis]
C. sieboldiiGreenidea okajimai;
Metanipponaphis cuspidatae, rotunda, shiicola;
Neonipponaphis shiiae; Nipponaphis monzeni
C. subacuminata Eutrichosiphum pasaniae; Mollitrichosiphum tenuicorpus
C. submaculaEutrichosiphum pasaniae
C. subsericeaEutrichosiphum pasaniae
C. tribuloidesEutrichosiphum pasaniae, [pseudopasaniae];
Metanipponaphis assamensis
Castanopsis sp(p). Eutrichosiphum dubium, [flavum], kumaoni, [neoalnicola],
[neotattakanum], russellae;
Greenidea [kunmingensis], sikkimensis;
Lachnus [quercihabitans], shiicola, sorini;
Metanipponaphis rotunda; Mollitrichosiphum niitakaensis;
Parathoracaphis manipurensis;
Schizoneuraphis querciphaga

Key to aphids feeding on Castanopsis:-

1 Aptera with head, thorax and ABD TERG 1 fused as prosoma. Legs and antennae much reduced, often concealed beneath body. SIPH small or absent. Antennae of alata with narrow ring-like sensoria…..2
Aptera of normal aphid form with well-developed legs and antennae. SIPH evident, conical or tubular. Antennae of alata with circular or oval sensoria…..12
2 Aptera without SIPH…..3
Aptera with SIPH usually present as small pores or cones…..4
3 Tarsi and claws rudimentary; dorsum strongly reticulated (fig.36A) …..Reticulaphis shiiae
Two-segmented tarsi and claws developed; dorsum without reticulation …..Parathoracaphis manipurensis
4 Dorsal cuticle of prosoma mainly smooth except for areolation, pustules only present around thoracic spiracles. Prosomal hairs long and thick with somewhat tuberculate bases. ABD TERG 8 with 4 hairs…..Schizoneuraphis querciphaga
Dorsal cuticle of prosoma ornamented with numerous raised pustules or translucent rounded or curved areas (figs 36B – E). Prosomal hairs short or if long then fine. ABD TERG 8 with 2-10 hairs…..5
5 Abdominal plate (ABD TERG 2-7) distinctly separate from prosoma (e.g. fig. 36B). ABD TERG 8 with 4-8 hairs…..6
Abdominal plate fused with or not distinctly separate fom prosoma, at least in median area (fig. 36C). ABD TERG 8 with 2-10 hairs…..7
6 Pustules on prosoma irregularly-shaped, angular, especially on marginal areas (Fig. 36A, B). Spinal and marginal hairs of prosoma longer, but not thicker or stiffer, than scattered dorsal hairs. ABD TERG 8 with 4-6 hairs….. Neonipponaphis shiiae
Pustules on prosoma smaller and oval or rounded. Spinal and submarginal hairs of prosoma distinctly thicker and stiffer as well as longer than scattered dorsal hairs. ABD TERG 8 with 6-8 hairs…..Neonipponaphis pustulosus*
7 Prosoma ornamented with blunt conical nodules, often longer than their basal widths (fig. 91A). Prosomal hairs very long and very fine…..Nipponaphis monzeni
Prosoma if pustulate then the pustules are low, all or mostly shorter than their basal widths (fig. 36). Prosomal hairs long or short…..8
8 ABD TERG 8 with 2-4 hairs. Prosoma dorsally ornamented with densely packed, evenly distributed, rather uniform-sized, circular or oval pustules (fig. 36C)…..Metanipponaphis spp.
ABD TERG 8 with 4-6 hairs. Prosoma with polygonal, angular or irregular dorsal ornamentation; if pustulate, then the pustules are of irregular size and shape …..9
9 Prosoma strongly convex dorsally, with irregular translucent branched or curved ornament-ation (fig. 36D). ABD TERG 8 with 6 hairs…..Lithoaphis shiiae
Prosoma somewhat flattened dorsally, with variable pustulate or polygonal ornamentation (e.g. fig. 36E). ABD TERG 8 with 4 hairs…..10
10 Prosomal hairs only 10-20 µm long, and those on ABD TERG 8 only 35-40 µm long…..Nipponaphis brevipilosa
Prosomal hairs 40-125 µm long, and those on ABD TERG 8 65-160 µm long …..11
11 Prosoma with only 6-7 hairs (2-3 spinal, 4 marginal) on each thoracic tergite, and 4 hairs (2 spinal, 2 marginal) on ABD TERG 1…..Nipponaphis javanica
Prosomal hairs much more numerous; 30-70 per tergite …..Nipponaphis multisetosa
12 SIPH tubular, bearing numerous long hairs…..13
SIPH as shallow hairy cones…..27
13 SIPH of aptera with pale reticulation either basally or over much of length. Cauda with a distinct median conical papilla (as in fig. 92B)…..14
SIPH of aptera without any pale reticulation. Cauda without a median papilla …..17
14 SIPH of aptera with a spinulose reticulation over the entire length, except for a small distal part with spinules only. BL 2.4-3.4 mm…..Greenidea magna*
SIPH with reticulation restricted to basal zone. BL 1.3-2.8 mm…..15
15 Ventral abdomen with spinulosity confined to marginal areas …..Greenidea pallidipes*
Mid-ventral area of abdomen evenly spinulose…..16
16 R IV+V 1.3-1.8 × longer than HT II…..Greenidea okajimai
R IV+V 1.85-2.5 × longer than HT II…..Greenidea sikkimensis*
17 Hind tibiae with transverse (stridulatory?) ridges (e.g. fig. 27A )…..18
Hind tibiae without transverse ridges…..19
18 Antennae 5- or 6-segmented. SIPH of aptera less than 0.5 × BL …..Mollitrichosiphum niitakaensis
Antennae 6-segmented. SIPH of aptera 0.65 or more × BL …..Mollitrichosiphum tenuicorpus
19 Longest hairs on antennae and dorsum distinctly capitate (fig. 92C) …..Allotrichosiphum kashicola
Hairs on antennae and dorsum with pointed, blunt, expanded or bifurcate apices, but never capitate…..20
20 Dorsum of aptera without spinules, or with spinules restricted to marginal areas …..21
Dorsum of aptera with numerous irregular transverse rows of minute spinules …..26
21 Femora and basal parts of tibiae as dark as or darker than body. ANT PT/BASE less than 1. First tarsal segments with 5 hairs…..22
Femora and tibiae paler than body. ANT PT/BASE more than 1. First tarsal segments with 7 hairs …..23
22 R IV+V 1.7-2.0× HT II, which is 0.10-0.11 mm long. Mid-dorsal abdominal hairs much shorter than marginal hairs…..Mesotrichosiphum pentaiarticulatum*
R IV+V 2.1-2.4× HT II, which is 0.08-0.09 mm long. Mid-dorsal abdominal hairs similar in length to marginal hairs….. Eutrichosiphum nigrum*
23 R IV+V 3.1-3.6× HT II…..Eutrichosiphum russellae
R IV+V 1.9-2.8× HT II…..24
24 BL 1.2-1.7 mm. SIPH 0.19-0.22 × BL…..Eutrichosiphum pullum*
BL 1.9-2.9 mm. SIPH 0.25-0.35 × BL…..25
25 Dorsal abdomen with extensive (but variably pigmented) sclerotisation. Marginal areas and venter of abdomen finely spiculose…..Eutrichosiphum tattakanum
Dorsal abdomen unsclerotised. Marginal areas an venter of abdomen smooth…..Eutrichosiphum kumaoni*
26 Aptera with R IV+V 1.5-1.7 × HT II, and SIPH longer than maximum body width. SIPH of alata more than 1.5 × ANT III…..Eutrichosiphum shiicola
Aptera with R IV+V 1.8-2.6 × HT II, and SIPH shorter than maximum body width. SIPH of alata less than 1.5 × ANT III…..27
27 Dorsum of aptera pale, SIPH mostly dark but pale at base, and at least 0.7 × maximum body width…..Eutrichosiphum sinense
Dorsum of aptera pale or dark brown, SIPH wholly dark and 0.5-0.6 × maximum body width…..Eutrichosiphum pasaniae
28Abdomen bearing a large rounded tubercle on ABD TERG 4, its base about as broad as that of SIPH cones (and another much smaller and flatter tubercle on ABD TERG 5) …..Lachnus sorini
Abdomen without a large tubercle on ABD TERG 4…..29
29 Longest hairs on ANT III 2.0-2.25 × basal diameter of segment. SIPH on large hairy cones which are about 3.4- 5.3 × longer than the diameter of the siphuncular pore. R IV+V 1.1-1.2 × HT II…..Lachnus shiicola
Longest hairs on ANT III 0.67-1.4 × basal diameter of segment. SIPH on small hairy cones which are 2-3 × longer than the diameter of the siphuncular pore. R IV+V 0.74-1.05 × HT II…..30
30 Longest hairs on ANT III 0.67-0.85 × basal diameter of segment. R IV+V 0.74-0.82 × HT II. Forewing of alata with large clear areas between media and cubitus veins, and between Cu1b and base of wing…..Lachnus acutihirsutus
Longest hairs on ANT III 0.9-1.4 × basal diameter of segment. R IV+V 0.9-1.05 × HT II. Forewing of alata mostly pigmented with only small clear areas …..Lachnus tropicalis
Castanospermum Fabaceae
Castanospermum australe Australian Chestnut
Betacallis querciphaga; Mollitrichosiphon tenuicorpus
CastillejaOrobanchaceae
Castilleja affinis ssp. neglecta Nasonovia castelleiae
C. cocciniaNasonovia castelleiae
C. exserta (see Orthocarpus)[Macrosiphum orthocarpus]
C. foliolosaBrachycaudus helichrysi
C. linariifoliaNearctaphis hottesi
C. miniataNasonovia castelleiae
C. neglecta = C. affinis ssp. neglecta
C. occidentalisNasonovia sampsoni
C. pavloviiNasonovia castelleiae
C. pruinosaNasonovia sampsoni
C. raupiiNasonovia castelleiae
C. wightiiNasonovia sampsoni; Macrosiphum euphorbiae
Castilleja spp.Aphis sp. (Montana, USA; BMNH collection, leg. D Hille
Ris Lambers);
Cedoaphis incognita (as Aphis chipetae Hottes);
[Macrosiphum sp.]; Nearctaphis bakeri, kachena

Key to aphids on Castilleja:-

1ANT (of apt.) with secondary rhinaria…..2
ANT without secondary rhinaria…..5
2Head spiculose. SIPH 3-4 × cauda, which is shorter than its basal width and bears more than 20 hairs…..Cedoaphis incognita
Head not spiculose. SIPH 0.8-2.2 × cauda which is much longer than its basal width and bears 5-12 hairs…..3
3SIPH 0.25-0.35 × BL, with a subapical zone of polygonal reticulation …..Macrosiphum euphorbiae
SIPH 0.06-0.22 × BL, without any polygonal reticulation…..4
4R IV+V 1.7-2.5 × HT II, with 20-25 accessory hairs. SIPH only weakly imbricated, 1.5-2.1 × cauda…..Nasonovia sampsoni
R IV+V 1.0-1.5 × HT II, with 6-10 accessory hairs. SIPH strongly imbricated, with rows of spinules on the imbrications; 0.8-1.3 × cauda….. Nasonovia castelleiae
5 SIPH smooth, head smooth, cauda helmet-shaped …..Brachycaudus helichrysi
SIPH imbricated or with rows of spinules. If head smooth then cauda tongue-shaped …..6
6SIPH imbricated and at least 0.1 × BL. Head smooth. ABD TERG 1 and 7 with marginal tubercles (MTu), which are absent from or only sporadically present on 2-5 …..Aphis sp. (Montana, USA; BMNH collection, leg. D Hille Ris Lambers)
SIPH spinulose and less than 0.09 × BL. Head spiculose. ABD TERG 2-5 with MTu, 1 and 7 without MTu…..7
7Second tarsal segments smooth or almost smooth…..Nearctaphis kachena
Second tarsal segments with distinct imbrication…..8
8Dorsal abdominal hairs arising from dark scleroites, and ABD TERG 7 and 8 with dark cross-bands. R IV+V usually shorter than ANT V…..Nearctaphis bakeri
Dorsal abdomen without dark markings. R IV+V usually longer than ANT V…..Nearctaphis hottesi
Casuarina Casuarinaceae
Casuarina equisetifolia Aphis gossypii; [Lachnus ?tropicalis];
Myzus persicae
C. huegelianaAphis gossypii; Myzus persicae
C. torulosaAphis (Toxoptera) aurantii

Use key to polyphagous aphids .

CatabrosaPoaceae
Catabrosa aquatica Cavariella aquatica; Rhopalosiphum padi; Sipha glyceriae

Use key to apterae of grass-feeding aphids under Digitaria.

Catalpa Bignoniaceae
Catalpa bignonioides Aphis aurantii, catalpae, gossypii; Myzus persicae
C. hybridaAphis aurantii, gossypii; Myzus persicae
C. ovataAphis gossypii
C. speciosaAphis catalpae, [frangulae], gossypii
Catalpa sp. Aphis fabae, nerii, spiraecola; Aulacorthum solani;
Macrosiphum euphorbiae; Myzus ornatus

Key to species on Catalpa:-

1 Antennal tubercles well-developed…..go to key to polyphagous aphids
Antennal tubercles weakly developed…..2
2 SIPH and cauda both very dark…..go to key to polyphagous aphids
Cauda pale or dusky, SIPH pale, dusky or dark…..3
3 Alata usually without any secondary rhinaria on ANT IV (rarely 1-2). Aptera with SIPH uniformly dusky to dark, and 1.3-2.5 × cauda…..Aphis gossypii
Alata with 1-4 rhinaria on ANT IV. Aptera with SIPH usually paler towards base, and 1.10-1.35 × cauda…..Aphis catalpae
CatamixisAsteraceae
Catamixis baccharoides [Acyrthosiphon rubi]
CatanancheAsteraceae
Catananche caerulea Protaphis terricola
CatapodiumPoaceae
Catapodium marinum Sipha glyceriae
Catharanthus Apocynaceae
Catharanthus roseus Aphis fabae, gossypii, spiraecola;
Macrosiphum euphorbiae, [stellariae];
Myzus [certus], ornatus, persicae;
[Nasonovia ribisnigri]; Rhopalosiphoninus staphyleae;
[Rhopalosiphum nymphaeae]

Use key to polyphagous aphids.

Catharinea see AtrichumPolytrichaceae
Catimbium see AlpiniaZingiberaceae
CattleyaOrchidaceae
Cattleya harrisoniana Cerataphis orchidearum
C. lobata Sitobion luteum
C. lueddemanniana Aphis (Toxoptera) aurantii
C. speciosissima = C. lueddemanniana
Cattleya spp.Sitobion anselliae, luteum

Use key to apterae of orchid-feeding aphids under Cymbidium.

CatunaregamRubiaceae
Catunaregam spinosa Aphis (Toxoptera) aurantii; Myzus persicae
C. tomentosa Aphis spiraecola

Use key to polyphagous aphids.

CaucalisApiaceae
Caucalis anthriscus Cavariella aegopodii;
Dysaphis crataegi ssp. aethusae
C. incognita = Agrocharis incognita
C. lappula = C. platycarpos
C. latifolia =Turgenia latifolia
C. platycarposAphis [craccivora], fabae; Hyadaphis foeniculi;
Semiaphis dauci
Caucalis sp.Aphis spp. (England, BMNH collection; Turkey, BMNH
collection)

Key to aphids on Caucalis (and Turgenia):-

1ABD TERG 8 with a supracaudal process. SIPH clavate. ANT PT/BASE 0.7-1.25 …..Cavariella aegopodii
No supracaudal process. SIPH tapering. ANT PT/BASE 1.8-5.5…..2
2Cauda not longer than its basal width…..3
Cauda much longer than its basal width…..4
3SIPH dark. ANT III more than 2 × ANT V…..Dysaphis crataegi aethusae
SIPH pale/dusky. ANT III about 1.1 × ANT V …..Brachycaudus crassitibiae*
4 SIPH and cauda mainly pale (SIPH often dark-tipped). Head spiculose, with ANT tubercles well developed, their inner faces approximately parallel …..Aulacorthum solani
SIPH dark, cauda pale, dusky or dark. Head not spiculose, ANT tubercles weakly developed…..5
5SIPH very small and flangeless, c.0.5 × cauda, with aperture slanted toward midline …..Semiaphis dauci
SIPH at least 0.6 × cauda, with an evident flange…..6
6SIPH at least somewhat swollen proximal to apex. ABD TERG 1 and 7 without marginal tubercles (MTu)…..7
SIPH tapering, without any trace of swelling. ABD TERG 1 and 7 with MTu .….8
7 SIPH clavate, 0.9-1.4 × cauda and 1.6-2.8 × HT II…..Hyadaphis foeniculi
SIPH thick on basal half and slightly swollen proximal to apex (fig. 41b), 0.6-0.8 × cauda and 0.9-1.3 × HT II…..Hyadaphis coriandri
8Dorsum without dark pigmentation . Cauda pale or dusky, distinctly paler than SIPH …..Aphis gossypii
Dorsum with at least some dark pigmentation. Cauda and SIPH equally dark …..9
9ANT PT/BASE 1.6-2.2. ABD TERG 2-4 without MTu. Dorsal pigmentation when extensive fused between segments to form a shield. ABD TERG 8 with only 2 hairs about equal in length to or shorter than ANT BD III. Longest hairs on hind femur shorter than trochantro-femoral suture…..Aphis sp. (Turkey, BMNH collection)
ANT PT/BASE 2.1-4.1 (if less than 2.4 then ABD TERG 2-4 with MTu). Dorsal pigmentation consisting of segmentally-arranged cross-bands, not fused between segments. ABD TERG 8 with 2-7 hairs much longer than ANT BD III. Longest hairs on hind femur much longer than trochantro-femoral suture…..10
10ABD TERG 2-4 regularly with large papillate MTu. R IV+V 0.17-0.18 mm, 1.2-1.5 × HT II. ANT PT 1.7-1.9 × R IV+V…..Aphis sp. (England, BMNH collection)
– ABD TERG 2-4 irregularly with small MTu. R IV+V 0.12-0.165 mm, 0.9-1.1 × HT II. ANT PT 2.0-2.8 × R IV+V…..Aphis fabae
CayaponiaCucurbitaceae
Cayaponia sp.Delfinoia peruviana
CayratiaVitaceae
Cayratia ibuensis Aphis gossypii
C. japonicaAphis gossypii; Greenidea cayratiae;
Macrosiphoniella cayratiae

Key to apterae on Cayratia:-

1SIPH c.0.46-0.50× BL, with numerous long hairs…..Greenidea cayratiae
SIPH much shorter and without hairs…..2
2SIPH with a distal zone of polygonal reticulation extending for about half their lengths. ANT tubercles prominentMacrosiphoniella cayratiae*
SIPH without polygonal reticulation. ANT tubercles weakly developed …..Aphis gossypii
CeanothusRhamnaceae
Ceanothus cordulatus Illinoia ceanothi
C. cuneatusAphis ceanothi
C. hirsutus = C. oliganthus
C. integerrimus Aphis ceanothi
C. oliganthus Aphis ceanothi
C. sanguineusAphis ceanothi
C. thyrsiflorusAphis ceanothi
C. velutinusAphis boydstoni, ceanothi; Illinoia ceanothi
Ceanothus spp. Macrosiphum euphorbiae; Neomyzus circumflexus

Key to aphids on Ceanothus:-

1ANT tubercles weakly developed. ANT PT/BASE 1.5-2.8. SIPH and cauda dark. ABD TERG 1 and 7 with marginal tubercles…..2
ANT tubercles well developed. ANT PT/BASE longer. SIPH and cauda pale or dusky. ABD TERG 1 and 7 without marginal tubercles…..3
2Marginal tubercles small and only present on ABD TERG 1 and 7. Dorsal abdomen with large black presiphuncular sclerites, often linked by a transverse sclerite on ABD TERG 6 ……Aphis ceanothi
Marginal tubercles broad, nearly flat and present on all of ABD TERG 1-7. Dorsal abdomen pale, without any presiphuncular sclerites……Aphis boydstoni
3SIPH very long and thin, 2.2-3.1 × cauda; narrow in middle, with distal part dusky and somewhat swollen, narrowing again before apex, with usually some subapical reticulation …..Illinoia ceanothi
SIPH less than 2.5 × cauda…..go to key to polyphagous aphids
Cecropia Cecropiaceae
Cecropia peltata Aphis aurantii, gossypii, spiraecola
C. hondurensis = C. peltata

(Use key to polyphagous aphids)

CedrelaMeliaceae
Cedrela odorataWest Indian or Mexican Cedar
Aphis (Toxoptera) aurantii
C. serrata[Chromaphis hirsutustibus]
C. sinensisAphis odinae

(Use key to polyphagous aphids.)

Cedrus Cedars Pinaceae
Cedrus atlantica Cinara cedri, laportei, tellenica; Schizolachnus pineti
C. deodaraCinara cedri, confinis, curvipes, deodarae,
laportei, [tenuipes];
Illinoia morrisoni; [Mindarus abietinus]; [Stomaphis sp.]
C. libaniCinara cedri, curvipes, laportei
C. libani ssp. brevifolia Cinara cedri ssp. brevifoliae, laportei

Key to aphids on Cedrus:-

1 ANT PT/BASE more than 1. SIPH long and tubular, swollen distally …..Illinoia morrisoni
ANT PT/BASE less than 1. SIPH are broad hairy cones…..2
2 R V short, flask-shaped, pointed only at tip, hardly longer than its basal width (fig. 69B). SIPH cones with few hairs, in 1-2 rings around pore…..Schizolachnus pineti
R V acutely pointed, dagger-shaped, usually twice or more as long as its basal width (as in fig. 69A). SIPH cones large and dark with numerous hairs…..3
3 Antenna 5-segmented. Dorsal hairs of aptera club-shaped, ornamented with numerous barbules (fig. 37A)…..Cinara laportei
Antenna 6-segmented. Dorsal hairs normal, pointed…..4
4 Hairs on body and appendages short; those on ANT III maximally about as long as basal diameter of segment…..Cinara curvipes
Hairs mostly long; longest hairs on ANT III maximally more than 2 × basal diameter of segment…..5
5 Dorsal length of HT I shorter than basal width. BL 3.8-7.8 mm …..Cinara confinis
Dorsal length of HT I as long as or longer than basal width (e.g. fig. 37B). BL 2.2-3.6 mm…..6
6 ABD TERG 1-6 with an extensive pattern of dark sclerotisation …..Cinara deodarae*
ABD TERG 1-6 without any extensive dark sclerotisation…..7
7 Dorsal length of HT I 0.045-0.060 mm, 1.0-1.12 times longer than basal width. Longest hairs on ABD TERG 7 are 0.090-0.144 mm, and on hind tibia 0.096-0.132 mm …..Cinara tellenica*
Dorsal length of HT I 0.060-0.090 mm, 1.2-1.7 times longer than basal width. Longest hairs on ABD TERG 7 are 0.162-0.240 mm, and on hind tibia 0.156-0.240 mm …..8
8 Femora and tibiae mainly pale on basal halves. R IV 2.0-2.5 × R V. ANT V 1.2-1.4 × ANT VI…..Cinara cedri
Femora and tibiae mainly dark throughout. R IV 1.8-2.1 × R V. ANT V 1.0-1.2 × ANT VI…..Cinara cedri ssp. brevifoliae*
Ceiba (including Chorisia) Malvaceae
Ceiba anfructosa Aphis gossypii
C. pentandraAphis aurantii, gossypii
C. speciosaAphis citricidus, gossypii; Macrosiphum euphorbiae;
Myzus persicae

Use key to polyphagous aphids.

CelastrusCelastraceae
Celastrus articulatus Aphis [celastrii], gossypii; Pseudomegoura magnoliae
C. flagellarisAphis [celastrii], gossypii, odinae
C. orbiculatusAphis [celastrii], fabae, gossypii, odinae, spiraecola;
Pseudomegoura magnoliae
C. scandens[Acyrthosiphon pisum];
Aphis craccivora, fabae, gossypii, spiraecola;
Aulacorthum solani; Macrosiphum euphorbiae
C. strigillosusAphis spiraecola

Use key to polyphagous aphids.

CelmisiaAsteraceae
Celmisia glandulosa Aulacorthum solani; Brachycaudus helichrysi

Use key to polyphagous aphids.

CelosiaAmaranthaceae
Celosia argentea Aphis fabae, gossypii; Myzus persicae
(incl. var. cristata)
C. plumosa = C. argentea
C. trigynaAphis gossypii
Celosia sp.Aphis spiraecola

Use key to polyphagous aphids.

Celtis Ulmaceae
Celtis africanaAphis aurantii; Shivaphis celti
C. aurantiacaAphis gossypii; Shivaphis szelegiewiczi
C. australisAphis aurantii, craccivora, spiraecola; Myzus persicae;
Shivaphis catalpinari, celti, celticola
C. berteroanaAphis aurantii
C. biondiiShivaphis catalpinari, celti, szelegiewiczi
C. bungeanaAphis aurantii, craccivora, spiraecola; Shivaphis celti;
C. caucasica = C. australis
C. cinnamomia Shivaphis celti
C. eriocarpa = C. australis
C. formosanaAulacorthum solani
C. hamiltoniShivaphis celti
C. iguanaeaAphis aurantii
C. japonica see sinensis
C. jessoensisMacromyzella celticola; Prociphilus oriens;
Shivaphis celti, tilisucta
C. julianaeShivaphis celti, hangzhouensis
C. koraiensis[Myzocallis carpini]; Shivaphis catalpinari, celti, tilisucta;
Stomaphis yanonis
C. kunmingensis Shivaphis celti
C. laevigataShivaphis celti
C. latifoliaAphis spiraecola
C. nervosaShivaphis celti
C. occidentalisAphis fabae; [Drepanosiphum platanoidis];
[Phorodon humuli]; Shivaphis celti; [Tinocallis platani]
C. sinensis (incl. japonica) Aphis aurantii, [celtis], craccivora, spiraecola;
[Indomegoura indica]; Paracolopha morrisoni; Pseudomegoura magnoliae;
Shivaphis catalpinari, celti, hangzhouensis, szelegiewiczi,
tilisucta;
Stomaphis yanonis
C. talaAphis gossypii
C. tetrandra (incl. var. Shivaphis celti; Sumatraphis celti
hamiltoni)
C. triandraShivaphis celti
C. willdenowiana = C. sinensis
Celtis sp. [Sumatraphis tubercaudatus]

Key to species on Celtis:-

(The separation of Shivaphis spp. in couplets 6-10 is largely based on Quednau 2003.)

1 ANT PT/BASE more than 1…..2
ANT PT/BASE less than 1…..3
2 Head with well-developed, scabrous, apically convergent antennal tubercles. SIPH cylindrical with a well-developed flange and 2-4 subapical rows of polygonal reticulation ….. Macromyzella celticola
Without that combination of characters …..go to key to polyphagous aphids, but note that populations running to Aphis (Toxoptera) aurantii may be A. (T.) celtis (described as having alatae with 3-4 rhinaria on ANT IV)
3 (Alata emerging in spring from galls or leaf-nests.) Media of forewing unbranched …..4
(Apterae and alatae free-living.) Media of forewing of alata once- or twice-branched …..5
4 (Alata from closed gall.) BL less than 3 mm. Hind wing with one oblique vein. Secondary rhinaria on ANT III-VI, many of them almost completely encircling …..Paracolopha morrisoni
(Alata from leaf-nest.) BL more than 4 mm. Hind wing with 2 oblique veins arising from a common base. Secondary rhinaria on ANT III-V (not VI), narrowly transverse but not extending more than half way around segment…..Prociphilus oriens
5 BL more than 4mm. Rostrum longer than body…..Stomaphis yanonis
BL less than 3 mm. Rostrum shorter than body…..6
6 Antenna 4-segmented in aptera, 5-segmented in alata (where known). Posterior abdomen with marginal processes. SIPH tubular, swollen, constricted apically, and with a subapical ring of 4 hairs (fig. 38A)…..Sumatraphis celti
Antenna 6-segmented. Abdomen without marginal processes. SIPH are pores, very small cones, or truncate, without a ring of hairs…..7
7 Forewing of alata with the membrane between media and Cu1a not bridged by a band of pigment. ANT PT very short, about 3 times as long as wide or less. Apterous viviparae as well as alatae present…..8
Forewing of alata with the membrane between media and Cu1a bridged by a band of pigment. ANT PT short, but at least 6 × longer than its maximum width. All adult viviparae are alate…..9
8 Apical part of cauda a rounded knob (fig. 38B). ANT III of alata with rhinaria in a line extending over most of length of segment. Fore coxae weakly enlarged, not visible from above at sides of pronotum…..Shivaphis catalpinari
Apical part of cauda finger-like, rather irregular in shape (fig. 38C). Alata with secondary rhinaria concentrated on central part of ANT III. Fore coxae strongly enlarged, visible from above at sides of pronotum…..Shivaphis celti
9 SIPH as truncate cones about as long as their midlength width (fig. 38D). Membrane between media and Cu1a of forewing bridged by a band of pigment that is broader than long. Dorsal abdomen with a complete series of spinal wax pore plates…..10
SIPH as very short cones, much shorter than wide, or merely as raised pores (figs 38E, F). Membrane between media and Cu1a of forewing with a bridging band of pigment that is not broader than long. Dorsal abdomen with spinal wax pore plates only well developed on ABD TERG 1, 2 and 8…..11
10ANT PT/BASE 0.64-0.79. R IV+V 0.155-0.163 mm long, 1.04-1.17 × HT II, and bearing 11-15 accessory hairs. Apices of tibiae spiculose…..Shivaphis (Sinishivaphis) hanzhouensis
ANT PT/BASE 0.41-0.60. R IV+V 0.090-0.098 mm long, about 0.75 × HT II, and bearing 9-10 accessory hairs. Apices of tibiae smooth …..Shivaphis (Sinishivaphis) tilisucta
11 ANT PT/BASE 0.29-0.40…..Shivaphis (Sinishivaphis) celticola
ANT PT/BASE 0.42-0.50…..Shivaphis (Sinishivaphis) szelegiewiczi
CenchrusPoaceae
Cenchrus bifloris Aphis gossypii
C. browniiSipha flava
C. ciliarisHysteroneura setariae; Pseudaphis sijui;
[Pterasthenia shiraensis]; Rhopalosiphum maidis;
Sipha flava; Sitobion africanum;
Tetraneura fusiformis
C. echinatusHysteroneura setariae; Rhopalosiphum maidis;
Tetraneura fusiformis
C. incertus Rhopalosiphum padi; Sipha flava
C. pauciflorus = C. incertus
C. setigerusHysteroneura setariae; Tetraneura fusiformis

Use key to apterae of grass-feeding aphids under Digitaria.

CenolophiumApiaceae
Cenolophium denudatum Aphis fabae, umbelliferarum; Cavariella aegopodii;
Dysaphis apiifolia (?ssp. petroselini), [koryakini];
Semiaphis [dauci], horvathi, sphondylii
C. fischeri = C. denudatum

Use key to apterae on Peucedanum.

Centaurea (incl. Cyanus)Asteraceae
Centaurea adpressa = C. scabiosa ssp. adpressa
C. africanaAphis gossypii
C. ambiguaUroleucon jaceae
C. americanaAphis fabae; Myzus persicae
C. alpestris = C. scabiosa ssp. alpestris
C. apiculata = C. scabiosa ssp. alpestris
C. arenariaAcaudinum centaureae; Macrosiphoniella staegeri; [Protaphis sp.]; Uroleucon jaceae
C. argentea[Aphis sp. – Leonard 1972a, 99]
C. aristata (incl langeana)Aphis craccivora; Macrosiphoniella staegeri; Paczoskia obtecta; Protaphis terricola; Uroleucon jaceae, jaceicola, Paczoskia obtecta; Protaphis hartigi, terricola
C. aspera
C. atropurpurea Aphis fabae; Uroleucon jaceae
C. balsamita = Stizolophus balsamita
C. behenAcaudinum beheni; Myzus persicae; Uroleucon jaceae
C. biebersteiniiMacrosiphoniella staegeri; Uroleucon jaceae
C. bracteataMacrosiphoniella staegeri; Uroleucon jaceae
C. caerulescens = C. hanryi
C. calcitrapaAphis fabae; Brachycaudus cardui; Myzus persicae;
Protaphis centaurea, hartigi, terricola; Uroleucon jaceae
C. carpatica = C. phrygia ssp. carpatica
C. cephalariifolia = C. scabiosa ssp. cephalariifolia
C. cheiranthifolia Aphis solanella
C. collinaUroleucon jaceae
C. crocodyliumAphis fabae; Uroleucon jaceae
C. cyanoides (?) Brachycaudus helichrysi
C. cyanus (= Cyanus segetum)Aphis fabae, magnopilosa, solanella, Aphis sp. (Italy, BMNH collection); Aulacorthum palustre, solani; Brachycaudus cardui, helichrysi; [Hyalopteroides humilis]; Macrosiphum euphorbiae; Myzus ascalonicus, persicae, ornatus; [Nasonovia ribisnigri]; Paczoskia obtecta; Protaphis terricola; Uroleucon compositae, [hypochoeridis], jaceae group, [montanivorum], [sonchi]; [Volutaphis centaureae]
C. dealbataBrachycaudus cardui; Uroleucon pepperi
C. debeauxiiUroleucon jaceae
C. depressaProtrama flavescens, radicis; Uroleucon jaceae, [sonchi]
C. deustaMacrosiphoniella staegeri; Uroleucon jaceae
C. diffusaMacrosiphoniella papillata; Protaphis middletonii, terricola; Uroleucon jaceae
C. hanryiProtaphis alexandrae, hartigi; Uroleucon
jaceae
C. hyalolepisAphis craccivora; Brachycaudus helichrysi
C. hyrcanicaUroleucon jaceae
C. ibericaAphis craccivora, fabae, gossypii,
magnopilosa, solanella
; Protrama radicis, [radicis ssp. asiatica]; Protaphis alexandrae, terricola; [Trama caudata]; Uroleucon jaceae, jaceae ssp. reticulatum
C. incana = C. pubescens
C. indurata = C. phrygia ssp. indurata
C. jacea (incl. ssp. banatica)Acaudinum centaureae, longisetosum; Aphis fabae, solanella; Brachycaudus cardui; Dysaphis centaureae; Paczoskia obtecta; Trama troglodytes; Uroleucon jaceae, jaceicola
C. kotschyanaUroleucon jaceae
C. lanulataMyzus persicae
C. macrocephala Myzus ascalonicus, ornatus, persicae
C. macroptilon Trama troglodytes
C. maculosaDysaphis centaureae; Macrosiphoniella
staegeri
; Protaphis terricola group
C. majoroviiUroleucon jaceicola
C. melitensisAcaudinum centaureae; Aphis fabae; Brachycaudus helichrysi; Protaphis terrcicola; Uroleucon jaceae
C. micranthos = C. biebersteinii
C. mollis = Cheirolophus sempervirens
C. monantha = Stemmacantha uniflora
C. montanaAphis fabae, nasturtii; Uroleucon montanivorum
C. moschataAphis fabae, solanella; Brachycaudus cardui; Myzus persicae; Uroleucon compositae
C. napifoliaBrachycaudus cardui, helichrysi; Protaphis
terricola
; Uroleucon jaceae
C. nicaeensis = C. sicula
C. nigraAcaudinum centaureae; Brachycaudus cardui, helichrysi; Myzus cymbalariae; Trama troglodytes; Uroleucon jaceae group, jaceicola
C. nigrescensMyzus persicae; Protaphis middletonii; Uroleucon jaceae
C. orientalisAcaudinum centaureae; Aphis fabae; Myzus persicae; Uroleucon jaceae
C. ornataUroleucon jaceae
C. oxylepis = C. macroptilon
C. pallescensAphis craccivora; Myzus persicae; Uroleucon jaceae
C. paniculataAcaudinum longisetosum; Brachycaudus helichrysi; Macrosiphoniella papillata, staegeri; Uroleucon jaceae, jaceicola, jaceicola ssp. pasqualei (?)
C. pannonicaUroleucon jaceae, jaceae ssp. henrichi
C. peliaAcaudinum centaureae; Aphis fabae
C. perrottettiAphis gossypii
C. phrygia (incl. carpatica, indurata, melanocalathia, salicifolia,
stenolepis
)
Dysaphis centaureae; Uroleucon jaceae, jaceae ssp. henrichi and ssp. reticulatum; [Volutaphis centaureae]
C. picris = Rhaponticum repens
C. procurrensBrachycaudus helichrysi; Paczoskia
obtecta
; Uroleucon jaceae
C. pseudophrygia = C. phrygia ssp. melanocalathia
C. pubescensBrachycaudus helichrysi
C. pulchella = Hyalea pulchella
C. pullataBrachycaudus helichrysi
C. rhenana = C. stoebe ssp. stoebe
C. riaeanaBrachycaudus helichrysi
C. ruthenicaAcaudinum centaureae; Aphis
gossypii
; Macrosiphoniella staegeri; Protaphis alexandrae; Uroleucon jaceae
C. scabiosa (incl. adpressa, alpestris, apiculata, cephalariifolia, sadleriana, tenuifolia)Acaudinum centaureae, longisetosum; Aphis fabae, Aphis spp. (BMNH colln, Italy and Sweden); Dysaphis centaureae; [Macrosiphum rosae]; Paczoskia obtecta; Protaphis hartigi, terricola; Protrama flavescens, radicis; Trama centaureae, troglodytes; Uroleucon jaceae, jaceae ssp. henrichi, jaceae ssp. reticulatum, jaceicola, [picridis]
C. sempervirens = Cheirolophus sempervirens
C. sergiiUroleucon jaceae
C. sibiricaProtaphis alexandrae
C. siculaBrachycaudus cardui, helichrysi; Uroleucon
compositae
C. solstitialisAcaudinum bulgaricum; Brachycaudus cardui; Macrosiphoniella papillata; Paczoskia obtecta; Protaphis alexandrae, hartigi, terricola; Uroleucon jaceae group
C. sphaerocephala (incl. polyacantha)Acaudinum centaureae; Protaphis terricola; Uroleucon jaceae
C. spinabadia = C. hanryi
C. squarrosa = C. virgata ssp. squarrosa
C. stenolepis = C. phrygia ssp. stenolepis
C. stoebeAcaudinum longisetosum, roumanicum; Aphis fabae; Dysaphis centaureae; Macrosiphoniella staegeri; Protaphis hartigi, terricola, Protaphis sp. (BMNH colln, Czech Republic and Switzerland); Protrama radicis; Trama centaureae, troglodytes; Uroleucon jaceae, jaceae ssp. henrichi, jaceae ssp. reticulatum, jaceicola
C. trichocephala Uroleucon jaceicola
C. triumfetti (incl. aligera)Aphis fabae; Paczoskia obtecta; Uroleucon jaceae, jaceicola
C. vallesiacaMacrosiphoniella staegeri
C. virgata (incl. ssp. squarrosa)Acyrthosiphon ilka; Aphis magnopilosa Macrosiphoniella papillata, staegeri, [Macrosiphoniella (Papillomyzus) sp. (Kadyrbekov 2014e)]; Protaphis alexandrae, [elatior], magnopilosa, terricola, Protaphis sp. (Kadyrbekov 2005b); Protrama radicis; Uroleucon jaceae, jaceae ssp. reticulatum, jaceicola, jaceicola ssp. kirgisica
C. vochinensis = C. nigrescens
Centaurea spp. Abstrusomyzus phloxae; [Brachycaudus sp. nr. pruniavium; Bodenheimer & Swirski 1957, 338]; Capitophorus eleaegni; Macrosiphoniella iranica, riedeli; Neomyzus circumflexus; Rectinasus buxtoni; Smynthurodes betae; [Titanosiphon dracunculi]; [Trama rara]; [Uroleucon erigeronense]

Key to apterae on Centaurea:-

1Antennae densely hairy; e.g. base of last antennal segment with more than 20 hairs …..2
Antennae less hairy; base of last antennal segment with less than 10 hairs ..…6
2HT II greatly elongated, more than 0.5 × hind tibia……3
HT II of normal length…..5
3SIPH present as large pores on low pigmented cones. Most apterae alatiform, with dark dorsal markings. ANT PT/BASE 0.4-0.6…..4
SIPH absent. Apterae without dark dorsal markings. ANT PT/BASE 0.14-0.3…..Trama centaureae or Trama troglodytes
4HT II 0.72-0.87 × length of hind tibia. Hind tibia 5.0-6.4 × ANT IV. R IV with 8-12 accessory (dorsal) hairs….. Protrama radicis
HT II 0.50-0.70 × length of hind tibia. Hind tibia 6.5-9.2 × ANT IV. R IV with 6-8 accessory (dorsal) hairs…..Protrama flavescens
5ANT V BASE and R IV+V both very long, respectively about 1.7 and 2.5 × width of head between antennal bases. ANT II similar in length to ANT I, much shorter than III .….Rectinasus buxtoni
ANT V BASE and R IV+V of normal length , both about 0.5 × width of head between antennal bases. ANT II about twice as long as ANT I, similar in length to III ..…Smynthurodes betae
6SIPH dark with a distal zone of polygonal reticulation. ANT III with 2-86 rhinaria …..7
SIPH pale or dark, if dark then without any polygonal reticulation. ANT III with 0-10 rhinaria….17
7ANT III with only 2-8 rhinaria on basal half. SIPH 0.9-1.3 × cauda. Crescent-shaped antesiphuncular sclerites present…..Macrosiphoniella staegeri
ANT III with 8-86 rhinaria. SIPH 1.05-2.8 × cauda. Antesiphuncular sclerites present or absent…..8
8Dorsal abdominal hairs all arising from pale tubercles…..9
Dorsal abdominal hairs all or mostly arising from dark scleroites…..11
9Hind tibiae with extensive pale middle regions. Hind femora dappled pale and dark, with a pale distal spot …..Macrosiphoniella iranica
Hind tibiae wholly black. Hind femora black over distal 0.5 or more of length …..10
10Femora pale over basal 0.3-0.5 of length…..Macrosiphoniella riedeli
Femora pale over only basal 0.1-0.2 of length…..Macrosiphoniella papillata
11Bases of SIPH almost ringed by large semicircular presiphuncular, and less extensive postsiphuncular, sclerites…..Paczoskia obtecta
Presiphuncular sclerites absent or fragmented…..12
12Coxae and cauda pale. SIPH 1.2-1.6 × cauda, which bears 23-39 hairs …..Uroleucon pepperi
Coxae dark. Cauda pale or dark, but if pale then cauda bears 7-18 hairs …..13
13ANT I bearing 10-15 hairs. SIPH pale in summer and dark in early spring, 2.0-3.0 × the pale cauda which bears 8-18 hairs…..Uroleucon jaceicola (s. str.)
ANT I bearing 6-8 hairs. SIPH 1.4-2.6 × cauda which is pale or dark, but if pale bears 7-11 hairs…..14
14SIPH 1.8-2.6 × the pale cauda which bears 7-11 hairs …..Uroleucon mongolicum
SIPH 1.4-2.2 × the dark cauda which bears 12-30 hairs…..15
15 Tibiae wholly dark. Hind femora with basal half pale and distal half dark, with a rather sharp transition between. ANT III with 16-54 rhinaria often confined to basal half (but up to 81 rhinaria extending over 0.85 of ANT III in alatiform specimens with rudimentary ocelli occurring when alatae are being produced in early summer). SIPH 1.4-1.8 × cauda …..Uroleucon jaceae
Tibiae with paler middle section. Hind femora pale over either much less or clearly more than half of length. ANT III with 28-86 rhinaria often extending over more than half of length. SIPH 1.7-2.2 × cauda…..16
16R IV+V 1.1-1.4 × HT II. Femora mainly dark, only pale on basal 0.2-0.3 of length …..Uroleucon compositae
R IV+V 1.6-2.0 × HT II. Femora pale over basal 0.67-0.75 of length …..Uroleucon montanivorum
17Cauda very broadly rounded, crescent-shaped, with length much less than half of its basal width…..18
Cauda helmet-shaped, triangular, tongue- or finger-shaped, with length more than half of its basal width…..22
18SIPH 2.3-4.0 × HT II, with minimum width not greater than width of hind tibia at midlength. Subgenital plate with 10-24 hairs on its anterior half…..19
SIPH usually 1.6-2.5 × HT II, with minimum width clearly greater than width of hind tibia at midlength. Subgenital plate with 2-4 hairs on anterior half…..21
19Femoral and trochantral hairs, and those on anterior abdominal sternites, short and blunt, maximally 0.4 × trochantro-femoral suture…..Acaudinum centaureae
Femoral, trochantral and ventral body hairs long, with finely pointed apices; not much shorter than trochantro-femoral suture…..20
20HT II 0.136-0.177 mm, and SIPH 0.49-0.75 mm, the product of the two lengths (HT II × SIPH) being 0.080-0.115…..Acaudinum longisetosum
HT II 0.125-0.150 mm, and SIPH 0.34-0.53 mm, HT II × SIPH being 0.042-0.077 …..Acaudinum roumanicum
21Femoral and trochantral hairs long and finely-pointed, maximally 0.7-1.05 × trochantro-femoral suture. SIPH 0.50-0.58 × ANT PT. (Al. without secondary rhinaria on ANT IV)…..Acaudinum beheni
Femoral and trochantral hairs short, mostly blunt, maximally 0.4 × trochantro-femoral suture. SIPH 0.39-0.49 × ANT PT. (Al. with 2-6 secondary rhinaria on ANT IV) …..Acaudinum bulgaricum
22Cauda helmet-shaped or triangular, 0.7-1.35 × its basal width…..23
Cauda tongue- or finger-shaped, more than 1.4 × its basal width…..28
23ABD TERG 1 and 7 always with marginal tubercles (MTu), larger than any MTu that may be present on other abdominal segments. Spinal tubercles (STu) absent. Cauda bluntly triangular, without any basal constriction…..24
ABD TERG 1 and 7 either without MTu, or MTu are present in association with similar large flat MTu on most other abdominal segments, and commonly also with STu on head and ABD TERG 7-8. Cauda helmet-shaped or pentagonal, often somewhat constricted at base …..26
24SIPH as short cones, clearly shorter than their basal widths and clearly shorter than (about 0.6 ×) cauda. MTu on ABD TERG 1 and 7 thin and tapering …..Xerobion zoijae*
SIPH as short tubes, cylindrical or slightly tapering, about as long as or longer than their basal widths and at least 0.7 × cauda. MTu on ABD TERG 1 and 7 quite large and broad-based…..25
25ANT PT/BASE 0.7-1.2. Dorsal abdominal pigmentation variable but never with dark cross-bands on all tergites…..Protaphis terricola group (incl. alexandrae, centaurea, hartigi, hyaleae and an undescribed species on Centaurea rhenana in C Europe)
ANT PT/BASE 1.7-2.3. Dorsal abdominal pigmentation variable but often comprising complete or fragmented dark cross-bands on all tergites …..Protaphis middletonii group
26 Large, flat MTu present on most segments, their diameters very much greater than that of spiracular apertures, which are broadly reniform and contiguous on ABD TERG 1 and 2. STu often present on head and ABD TERG 7-8…..Dysaphis centaureae
MTu and STu only intermittently or rarely present and much smaller than spiracular apertures, which are large and rounded and not contiguous on ABD TERG 1 and 2 …..27
27Dorsum with an extensive black shield. SIPH dark, imbricated, 1.7-3.4 × cauda. ANT III 0.31-0.47 mm, 2.4-3.4 × HT II…..Brachycaudus cardui
Dorsum without dark markings. SIPH pale, smooth-surfaced, 0.8-1.5 × cauda. ANT III 0.07-0.25 mm, 0.9-2.2 × HT II…..Brachycaudus helichrysi
28 Well-developed rounded marginal tubercles (MTu) present on ABD TERG 2-5, as well as very large ones on 1 and 7. R IV+V about equal in length to ANT III …..Aphis sp. (Italy, BMNH collection)
Papilliform MTu absent or sporadically present on ABD TERG 2-4; only ever consistently present on ABD TERG 1 and 7. R IV+V much shorter than ANT III…..29
29SIPH 1.9-2.2 × the similarly dark cauda. Papilliform MTu usually present on at least some of ABD TERG 2-4…..Aphis sp. (Sweden, BMNH collection)
SIPH 0.7-2.5 × cauda, but if more than 1.8 × then either SIPH and cauda are both pale or cauda is distinctly paler than dark SIPH, and MTu are rarely present on ABD TERG 2-4 …..30
30Cauda black with 6-8 hairs, and dorsum pale with only a dusky band on ABD TERG 8. R IV+V 1.2-1.3 × HT II. ANT PT/BASE 1.5-1.95 …..Aphis sp. (Italy, BMNH collection)
Cauda pale or dark; if black and with only 6-8 hairs then dorsum has extensive black sclerotisation, R IV+V is 0.8-1.0 × HT II and ANT PT/BASE 1.9-3.6 …..31
31ANT tubercles well-developed with smooth, divergent inner faces. SIPH without subapical polygonal reticulation…..32
Without that combination of characters. If ANT tubercles are well-developed then either they are steep-sided and somewhat spiculose or scabrous, or SIPH have subapical polygonal reticulation…..33
32Dorsal hairs thick and capitate, as long as ANT BD III or longer …..Capitophorus elaeagni
Dorsal hairs small and inconspicuous….. Acyrthosiphon ilka
33ANT tubercles well-developed, their inner faces steep-sided and slightly scabrous or spiculose. Head capsule without spicules dorsally, but slightly spiculose ventrally. ANT III with 1-3 small rhinaria near base. SIPH without polygonal reticulation …..Aulacorthum palustre
Without that combination of characters. If ANT tubercles are well-developed, then either head is markedly spinulose at least ventrally, with inner faces of ANT tubercles markedly scabrous and parallel or apically convergent, or SIPH have several rows of subapical polygonal reticulation. ANT III with 0-10 rhinaria …..go to key to polyphagous aphids
(specimens running to Aphis fabae could be A. magnopilosa Nevsky)
Centaurium (including Erythraea) Gentianaceae
Centaurium erythraea Aphis gentianae; Myzus cerasi, erythraeae;
Sciamyzus cymbalariae
C. littoraleMyzus cerasi
C. pulchellumAphis gentianae
C. tenuiflorumBrachyunguis harmalae
C. umbellatum = C. erythraea
C. vulgare = C. littorale

Key to apterae on Centaurium:-

1. ANT PT/BASE 0.4-0.7. SIPH 0.3-0.6 × cauda…..Brachyunguis harmalae
ANT PT/BASE more than 1. SIPH as long as or longer than cauda…..2
2Head smooth, ANT tubercles weakly developed, front of head straight or sinuous in dorsal view. Large, domed marginal tubercles (MTu) present on ABD TERG 1-5 and 7 …..Aphis gentianae
Head scabrous/spinulose, ANT tubercles well-developed, scabrous, their inner faces convergent. Small MTu irregularly present on ABD TERG 1-4, never on 7 …..3
3. SIPH black, tapering/cylindrical, more than 0.2 × BL and longer than ANT III …..Myzus erythraeae (= cerasi?)
SIPH pale/dusky, slightly swollen on distal half, less than 0.2 × BL and shorter than ANT III …..Myzus cymbalariae
CentothecaPoaceae
Centotheca lappacea Pentalonia gavarri (as nigronervosa?)
C. latifolia = C. lappacea
C. mucronataPseudoregma panicola

Use key to apterae of grass-feeding aphids under Digitaria.

CentranthusValerianaceae
C. angustifoliusAphis fabae, spiraephaga; Macrosiphum euphorbiae, rosae
C. calcitrapaAphis fabae, solanella; Macrosiphum rosae, euphorbiae;
Myzus ornatus
C. coccineus see C. ruber
C. macrosiphonAphis craccivora; Macrosiphum rosae; Myzus persicae
C. ruber (incl. var. coccineus) Aphis fabae, gossypii, solanella, spiraecola, spiraephaga;
Macrosiphum centranthi, euphorbiae, rosae;
Myzus ascalonicus, ornatus, persicae

Key to apterae on Centranthus:-

1SIPH with a subapical zone of polygonal reticulation…..2
SIPH without polygonal reticulation…..4
2Head and ANT I-II dark. SIPH wholly dark…..Macrosiphum rosae
Head and ANT I-II pale. SIPH pale at least at their bases…..3
3Apices of femora and SIPH dark. ANT 1.3-1.7 × BL. Longest hairs on ABD TERG 3 are 33-50 mm long. Cauda with 11-19 hairs…..Macrosiphum centranthi
Apices of femora and SIPH pale/dusky. ANT 0.9-1.4 × BL. Longest hairs on ABD TERG 3 are 20-37 mm long. Cauda with 8-12 hairs…..Macrosiphum euphorbiae
4 Head spiculose, with well-developed, steep-sided or apically convergent ANT tubercles. ABD TERG 1 and 7 without marginal tubercles (MTu) …..go to key to polyphagous aphids, starting at couplet 5
Head not spiculose, ANT tubercles weakly developed. ABD TERG 1 and 7 with MTu …..5
5 Abdomen without any dark markings on ABD TERG 1-6, and without or with only a small lightly-pigmented sclerites on ABD TERG 8, or 7 and 8 …..6
Abdomen with either a dark dorsal shield or at least some scattered dark markings on ABD TERG 1-6, following the polygonal pattern of reticulation of the cuticle, and usually with dark transverse sclerites on ABD TERG 7 and 8…..7
6 Cauda paler than SIPH, and bearing 4-7(-8) hairs. Longest hind femoral hairs only 0.4-0.7 × diameter of trochantro-femoral suture…..Aphis gossypii
Cauda as dark as SIPH, usually with a midway constriction, and bearing 7-15 hairs. Longest hind femoral hairs more than 0.8 × diameter of trochantro-femoral suture …..Aphis spiraecola
7 Dorsal abdomen with an extensive solid black sclerite centred on ABD TERG 4-5. Cauda rather pointed and bearing 4-7 hairs…..Aphis craccivora
Dorsal abdomen often with variably developed dark markings, but without an extensive black sclerite. Cauda rounded apically and bearing 7-27 hairs…..8
8 Longest hairs on ANT III 0.5-0.9 × BD III. R IV+V 0.65-0.92 × HT II. SIPH 0.7-1.1 × cauda. Femora pigmented throughout length…..Aphis spiraephaga
Longest hairs on ANT III 0.8-3.4 × BD III. R IV+V 0.9-1.4 × HT II. SIPH 0.8-1.9 × cauda. Femora with unpigmented section at base…..Aphis fabae or A. solanella
(for separation of these two species see couplet 35 of polyphagous aphids key)
CentrosemaFabaceae
Centrosema arenarium Aphis gossypii; Microparsus brasiliensis
C. pubescensAphis craccivora

Key for apterae on Centrosema:-

1ANT tubercles well-developed. SIPH with basal half pale, distal half dark and slightly clavate. (Alatae with black-bordered wing veins) …..Microparsus brasiliensis
ANT tubercles weakly developed. SIPH tapering, wholly dark…..2
2Dorsal abdomen with an extensive dark sclerite. Cauda dark …..Aphis craccivora
Dorsal abdomen without dark markings. Cauda paler than SIPH …..Aphis gossypii
CephalantheraOrchidaceae
Cephalanthera damasonium Aphis fabae, solanella
C. longifoliaAulacorthum solani
C. rubraAphis fabae
Cephalanthera sp. Aphis craccivora

Use key to polyphagous aphids, or try key to orchid-feeding aphids under Cymbidium.

CephalanthusRubiaceae
Cephalanthus occidentalis Aphis cephalanthi
CephalariaDipsacaceae
C. corniculata = C. uralensis
C. giganteaAphis cephalariae; Dysaphis cephalarioides;
Macrosiphum rosae
C. joppensisBrachycaudus helichrysi
C. joppica = C. joppensis
C. leucanthaDysaphis cephalarioides
C. syriacaAphis gossypii; Myzus persicae
C. tatarica = C. gigantea
C. uralensisDysaphis cephalarioides; Macrosiphum rosae

Key to apterae on Cephalaria:-

1Head black with well-developed ANT tubercles, their inner faces smooth and divergent. SIPH long and black, 0.3-0.45 × BL, with a subapical zone of polygonal reticulation …..Macrosiphum rosae
Without that combination of characters. If ANT tubercles are well developed then head and SIPH are not black…..2
2Large flat marginal tubercles (MTu) present on thorax and ABD TERG 1-5 and 7 (and some-times on 6), and similar spinal tubercles (STu) on head, pronotum, ABD TERG 1, 7 and 8. Dorsal abdomen with dark sclerites…..Dysaphis cephalarioides
MTu and STu if present then small and tubercular and restricted to fewer segments. Dorsal abdomen with or without dark sclerites…..3
3Dorsum with extensive dark sclerotisation varying from an almost solid carapace to broad cross-bands (the latter in small midsummer specimens). Longest hairs on ANT III 1.8-2.8 × BD III. ABD TERG 8 with 6-12 hairs and cauda with 12-20 hairs …..Aphis cephalariae
Without that combination of characters…..go to key to polyphagous aphids
Cephalonoplos see CirsiumAsteraceae
Cephalotaxus Cephalotaxaceae
Cephalotaxus drupacea [Cinara longipennis]; Mindarus japonicus
CerastiumCaryophyllaceae
C. alpinumMyzus certus, icelandicus, persicae, polaris
C. angustifolium = C. arvense
C. arvenseAphis cerastii, sambuci; Aulacorthum solani;
Brachycolus cerastii;
Myzus ascalonicus, certus, cymbalariae; [Sitobion avenae];
Smynthurodes betae
C. biebersteiniiMyzus cymbalariae
C. caespitosum = C. fontanum ssp. vulgare
C. cerastoidesAcyrthosiphon ilka; Aphidura alatavica;
Macrosiphum stellariae
C. davuricumBrachycolus cerastii, cucubali; Macrosiphum euphorbiae
C. diffusumMyzus certus
C. edmonstonii = C. nigrescens
C. fontanum (incl. Aphidura alatavica; Aulacorthum solani;
holosteoides, triviale, vulgare) Brachycaudus helichrysi; Brachycolus cerastii;
Macrosiphum euphorbiae;
Myzus ascalonicus, certus, cymbalariae, persicae, polaris
C. glomeratum Abstrusomyzus phloxae; Aphis fabae; Aulacorthum solani;
Brachycaudus helichrysi; Brachycolus cerastii;
Macrosiphum euphorbiae; Myzus ascalonicus, persicae
C. holosteoides = C. fontanum ssp. vulgare
C. ligusticumMyzus certus
C. macranthum Myzus cymbalariae
C. nigrescens Acyrthosiphon auctum
C. pumilumMyzus ascalonicus, certus, persicae
C. semidecandrum Aulacorthum solani; Myzus ascalonicus, certus, persicae
C. soleiroliiAphidura corsicensis
C. sylvaticumAulacorthum solani
C. tetrandrum = C. diffusum
C. tianschanicum Acyrthosiphon ilka; Aulacorthum solani;
Brachycolus cerastii, cucubali
C. tomentosum Aulacorthum solani; Brachycolus cerastii;
Myzus ascalonicus, certus, cymbalariae
C. triviale = C. fontanum ssp. vulgare
C. uniflorumThecabius cerastii
C. vulgatum =C. glomeratum
Cerastium spp. [Nasonovia brevipes]

Key to apterae on Cerastium:-

1ANT PT/BASE less than 0.5. SIPH absent…..2
ANT PT/BASE more than 1.5. SIPH present, tubular (sometimes small) …..3
2Primary rhinaria ringed with short hairs. Dorsal abdomen with wax pore plates …..Thecabius cerastii
Primary rhinaria with sclerotic, hairless rims. Dorsal abdomen without wax pore plates …..Smynthurodes betae
3Head smooth or wrinkled, or with a few spicules on ventral side only…..4
Head densely spiculose or nodulose…..16
4SIPH very small, less than 0.6 × cauda, conical or barrel-shaped, with flange reduced or absent…..5
SIPH more than 0.7 × cauda…..7
5SIPH much longer than their basal width, elongate barrel-shaped, about 0.5 × cauda, with a small flange and normal-sized aperture…..Brachycolus cucubali
SIPH shorter than or about as long as their basal width, less than 0.33 × cauda, flangeless and with a reduced aperture…..6
6ABD TERG 8 with a small rounded median process bearing two hairs. R IV+V at least 0.9 × HT II, and longer than ANT IV…..Brachycolus cerastii
ABD TERG 8 without a median process. R IV+V 0.55-0.72 × HT II, shorter than ANT IV …..Brachycolus stellariae
7ABD TERG 1 and 7 (at least) with marginal tubercles (MTu)…..8
ABD TERG 1 and 7 without MTu…..10
8MTU absent from ABD TERG 2-4, or only intermittently present and small on these segments…..Aphis fabae
Large MTu present on ABD TERG 2-4 as well as 1 and 7…..9
9SIPH uniformly dark, 2.1-3.5 × cauda. ANT PT/BASE 2.1-2.9 …..Aphis sambuci
SIPH paler at bases, less than 2 × cauda (?). ANT PT/BASE 3.2-3.6 …..Aphis cerastii*
10Cauda short, helmet-shaped, not longer than its basal width. SIPH with a subapical annular incision. Spiracular apertures large and rounded …..Brachycaudus helichrysi
Cauda tongue-shaped, longer than its basal width. Spiracular apertures reniform …..11
11SIPH with polygonal reticulation on subapical 0.12-0.20 of length …..12
SIPH without any distinct zone of polygonal reticulation…..13
12Femora usually with a dark spot or patch near apices (Fig.51a). ABD TERG 2-3 with longest hair 26-56 μm, usually as long as or longer than ANT BD III. Subgenital plate with 2-13 hairs in addition to those on posterior margin…..Macrosiphum stellariae
Femora pale or only slightly dusky at apices. ABD TERG 2-3 with longest hair 21-37 μm, usually shorter than ANT BD III. Subgenital plate with 2(-4) hairs on anterior part…..Macrosiphum euphorbiae
13Dorsal abdomen with dark sclerotisation, either as separate sclerites at base of dorsal hairs or as more extensive bars or broken patches. ANT shorter than BL, and ANT III without rhinaria. SIPH dusky/dark, especially towards apices, and slightly or distinctly swollen on distal half…..14
Dorsal abdomen without dark sclerotisation. ANT longer than BL. ANT III usually with 1-3 rhinaria near base. SIPH pale, tapering/cylindrical…..15
14 SIPH with very slight distal swelling, and 1.8-2.0 × cauda. Dorsal abdomen with separate rounded dark sclerites at bases of dorsal hairs…..Aphidura corsicensis
SIPH distinctly swollen on distal half, and 1.5-1.7 × cauda. Dorsal abdomen with variable but more extensive sclerotisation, consisting of a broken spino-pleural patch or cross-bands…..Aphidura alatavica
15 SIPH 0.25-0.33 × BL, and 1.5-2.4 × cauda…..Acyrthosiphon ilka
SIPH 0.11-0.17 × BL, and 0.85-1.33 × cauda….. Acyrthosiphon auctum
16SIPH tapering gradually from base to flange. ANT III usually with 1-2 small rhinaria near base…..Aulacorthum solani
SIPH slightly to moderately swollen distally. ANT III without rhinaria …..17
17SIPH 0.54-0.81 × ANT III…..18
SIPH 0.82-1.34 × ANT III…..19
18Inner faces of ANT tubercles approximately parallel in dorsal view. SIPH almost smooth or weakly imbricated, with narrowest part of basal “stem” not wider than hind tibia at midlength. Dorsal cuticle smooth or slightly wrinkled…..Myzus ascalonicus
Inner faces of ANT tubercles with convergent apices. SIPH heavily imbricated or scabrous, with narrowest part of stem a little wider than hind tibia at midlength. Dorsal cuticle scaly …..Myzus cymbalariae
19 ANT tubercles not apically convergent. SIPH rather short and thick, dark, with width of narrowest part of stem more than 0.13 of length. ANT 5- or 6-segmented, with ANT PT/BASE 1.1-2.8…..Myzus polaris
ANT tubercles apically convergent, or with apically convergent processes. SIPH pale or dusky with narrowest part of stem less than 0.13 of length. ANT always 6-segmented, with ANT PT/BASE 2.6-5.1…..20
20ANT tubercles themselves rather low, but with scabrous processes extending forward from ANT bases. SIPH weakly swollen subapically (over about distal 0.25). Dorsum with an evident reticulate pattern…..Abstrusomyzus phloxae
ANT tubercles broadly rounded, without forwardly-directed processes. SIPH slightly to moderately swollen over about distal 0.5. Dorsum without a reticulate pattern …..21
21R IV+V in most specimens with only one pair of lateral accessory hairs (plus 0-3 ventral accessory hairs). Value of function CAUDA/(ANT III × PT) in range 0.80-1.52, but rarely more than 1.25 except in small specimens (those with ANT III less than 0.32 mm) …..Myzus persicae
R IV+V in most specimens with two pairs of lateral accessory hairs. Value of function CAUDA/(ANT III × PT) in range 1.2-2.7 (rarely less than 1.25)…..22
22R IV+V shorter than or about as long as (0.85-1.1 × ) ANT BASE VI …..Myzus certus
R IV+V usually longer than (1.0-1.2 × ) ANT BASE VI …..Myzus icelandicus
Cerasus see PrunusRosaceae
CeratocarpusAmaranthaceae
Ceratocarpus arenarius Aphis craccivora
CeratocephalusRanunculaceae
Ceratocephalus falcatus Dysaphis pulverina
Ceratochloa see BromusPoaceae
Ceratoides Amaranthaceae
Ceratoides ewersmanniana = Krascheninnikovia ewersmanniana
C. latens = Krascheninnikovia ceratoides
C. papposa = Krascheninnikovia ceratoides
Ceratonia Fabaceae
Ceratonia. siliquaCarob
Aphis craccivora, gossypii
Use key to polyphagous aphids.
CeratophyllumCeratophyllaceae
Ceratophyllum submersus Sipha glyceriae
Ceratophyllum sp. Rhopalosiphum nymphaeae

Use key to apterae on Sagittaria.

CeratostigmaPlumbaginaceae
Ceratostigma willmottianum Myzus ornatus, persicae
CeratothecaPedaliaceae
Ceratotheca sesamoides Aphis gossypii
CercidiphyllumCercidiphyllaceae
Cercidiphyllum japonicum [Aphis sp. (Leonard 1972, 99)]
Aulacorthum cercidiphylli; Myzus persicae
C. magnificumAulacorthum cercidiphylli

Key to aphids on Cercidiphyllum:-

Inner faces of antennal tubercles parallel or slightly divergent in dorsal view. ANT III of aptera usually with 1-3 small rhinaria near base. Femora usually dark apically. Alata without a black dorsal abdominal patch…..Aulacorthum cercidiphylli
Inner faces of antennal tubercles convergent in dorsal view. ANT III of aptera never with rhinaria. Alata with a black dorsal abdominal patch…..Myzus persicae
Cercis Fabaceae
Cercis canadensis Longistigma caryae; Aphis pawneepae
C. chilensisAulacorthum solani
C. siliquastrum Judas Tree
Aphis craccivora, fabae, spiraecola; Myzus persicae

Key to apterae on Cercis:-

1 BL more than 4 mm. ANT PT/BASE less than 1. Alata with pterostigma extending around tip of forewing…..Longistigma caryae
BL less than 3 mm. ANT PT/BASE more than 1.5. Alata with pterostigma stopping short of forewing tip…..2
2 SIPH short and dark, similar in length to the dark triangular cauda which bears c.20 hairs. ANT PT/BASE slightly less than 2. Prothorax with a pair of very large marginal tubercles. Alata with 2-5 (commonly only 2) secondary rhinaria on basal part of ANT III …..Aphis pawneepae
Without that combination of characters…..go to key to polyphagous aphids
CercocarpusRosaceae
Cercocarpus montanus [Acyrthosiphon sp. nr pseudodirhodum; Aphis cercocarpi;
Illinoia gracilicornis]
C. parvifolius = C. montanus

Records of aphids collected/and or described from Cercocarpus in western USA are now thought to be based on a misidentification of another rosaceous shrub genus, Holodiscus (Jensen 2021).

CereusCactaceae
Cereus nycticaulus = Selenicereus grandiflorus
C. triangularisAphis (Toxoptera) aurantii
Cereus sp.Aphis gossypii

Use key to polyphagous aphids.

CerintheBoraginaceae
Cerinthe glabraBrachycaudus cerinthis; Macrosiphum cerinthiacum
C. majorBrachycaudus bicolor; Macrosiphum cerinthiacum
C. minorAphis fabae; Brachycaudus bicolor, cerinthis;
Macrosiphum cerinthiacum, euphorbiae, [stellariae]

Key to apterae on Cerinthe:-

1 Cauda semi-circular or helmet-shaped, shorter than its basal width. Spiracular apertures large and rounded. Dorsum with broad dark transverse bands, separate or partially fused between tergites. ANT tubercles undeveloped. ANT III without rhinaria. SIPH dark, without polygonal reticulation…..2
Without that combination of characters…..3
2. Large, flat marginal tubercles (MTu), usually larger than spiracles, present on all thoracic segments and ABD TERG 1-7. SIPH about 2 × cauda, with a large flange…..Brachycaudus bicolor
MTu only irregularly present and always smaller than spiracles. SIPH very short, conical, similar in length to or shorter than cauda, with an undeveloped or small flange …..Brachycaudus cerinthis
3ANT tubercles well developed, smooth, with inner faces divergent. ANT III with 1-20 rhinaria. SIPH long, mostly pale, with a darker or duskier subapical zone of polygonal reticulation; about 2 × the long finger-like cauda…..4
Without that combination of characters…..go to key to polyphagous aphids
4 Legs with dark spots near femoral apices. ANT III with 8-20 rhinaria …..Macrosiphum cerinthiacum
Femora pale or only slightly dusky at apices. ANT III with 1-10 rhinaria …..Macrosiphum euphorbiae
CerinthodesBoraginaceae
Cerinthodes paniculatum see Mertensia paniculata
Ceropegia Apocynaceae
Ceropegia linearis ssp. woodii = C. woodii
C. radicansAphis nerii
C. stapeliiformisAphis nerii
C. woodiiNeomyzus circumflexus

Use key to polyphagous aphids.

CeropterisPolypodiaceae
Ceropteris calomelanos Idiopterus nephrelepidis

(or try key to fern-feeding aphids under Polypodium)

CestrumSolanaceae
Cestrum aurantiacum Aphis fabae, spiraecola; Aulacorthum solani;
Myzus persicae
C. diurnumAphis aurantii, fabae, gossypii, spiraecola;
Aulacorthum solani; Myzus persicae
C. elegans Aphis fabae, spiraecola; Myzus persicae
C. euanthes Aphis solanella; Myzus persicae
C. fasciculatumAphis aurantii, fabae, gossypii, spiraecola;
Aulacorthum solani; Brachycaudus helichrysi;
[Greenideoida lutea]; Myzus ornatus, persicae;
Neomyzus circumflexus
C. laevigatumAphis spiraecola
C. laurifoliumAphis spiraecola
C. leucocarpum = C. nocturnum
C. newellii = C. fasciculatum
C. nocturnumAphis aurantii, craccivora, fabae, gossypii, solanella,
spiraecola;
Aulacorthum solani; [Eriosoma lanigerum];
Myzus persicae
C. parquiAphis aurantii, fabae, solanella, spiraecola;
Myzus persicae
C. pseudoquina = C. euanthes
C. purpureum = C. elegans
Cestrum spp.Aphis nasturtii, Aphis sp.(India, BMNH collection);
Pseudomegoura magnoliae; [Sitobion rosaeformis]

Key to apterae on Cestrum:-

SIPH and cauda both black, SIPH 0.8-0.9 × cauda which bears 6-8 hairs. ANT PT/BASE 1.6-1.95. R IV+V 1.1-1.3 × HT II ….. Aphis sp.(India, BMNH collection)
Without that combination of characters…..go to key to polyphagous aphids
Ceterach see AspleniumAspleniaceae
Ceterach officinarum see Asplenium ceterach
ChaenactisAsteraceae
Chaenactis douglasii Uroleucon (Lambersius) sp. (western USA, BMNH
collection)
ChaenomelesRosaceae
Chaenomeles japonica Aphis craccivora, fabae, frangulae, gossypii, nerii, pomi,
(incl. maulei)spiraecola, spiraephaga;
Aulacorthum solani;
Brachycaudus helichrysi, [persicae];
Illinoia macgillivrayae; Macrosiphum euphorbiae;
Myzus ornatus, persicae; Ovatus insitus, malisuctus;
Rhopalosiphum oxyacanthae, [nymphaeae, padi]
Ch. lagenariaAphis gossypii, nerii, pomi, spiraecola;
Brachycaudus helichrysi;
Dysaphis sp. (Japan; Stroyan 1985 and BMNH collection);
Macrosiphum euphorbiae; Myzus persicae;
[Sitobion sp. (Millar 1994)]
Ch. maulei = Ch. japonica
Ch. sinensisAphis spiraecola; Myzus persicae;
Ovatus insitus, Ovatus sp. near crataegarius (?malicolens;
Korea, BMNH collection and Japan, Moritsu 1983);
Prociphilus chaenomelis; Pseudomegoura magnoliae; [Sappaphis piri]
Ch. speciosaAphis citricidus, gossypii, pomi; Aulacorthum solani;
Myzus ornatus, persicae; Ovatus malisuctus;
Schizaphis chaenometicola; [Sitobion sp. (Millar 1994)]
Ch. trichogyna = Ch. japonica

Key to apterae on Chaenomeles (except first couplet, also applicable to alatae):-

1ANT PT/BASE less than 0.3. SIPH absent or as very small pores. Wax gland plates on head, thorax and abdomen…..Prociphilus chaenomelis
ANT PT/BASE more than 1.5. SIPH present, tubular. No wax gland plates …..2
2Head with well-developed ANT tubercles, their inner faces scabrous or at least somewhat spiculose, and steep-sided or apically convergent…..3
Head with ANT tubercles either absent or weakly developed, or very well developed and smooth and divergent…..8
3Genital plate enlarged and produced posteriorly. SIPH dark, very coarsely imbricated …..Ovatus malisuctus
Genital plate normal. SIPH pale, weakly to moderately imbricated…..4
4ANT III usually with 1-2 small rhinaria near base. Inner faces of antennal tubercles spiculose, approximately parallel…..5
ANT III without rhinaria. Inner faces of ANT tubercles scabrous, convergent apically …..6
5Dorsal side of head almost devoid of spicules. SIPH slightly clavate. Femora dark except at bases…..Pseudomegoura magnoliae
Head densely spiculose dorsally as well as ventrally. SIPH tapering/ cylindrical with no trace of swelling. Femora dark only at apices…..Aulacorthum solani
6SIPH slightly clavate. R IV+V 1.0-1.2 × HT II. ANT PT/BASE 3.1-4.6…..Myzus persicae
SIPH gradually tapering. R IV+V 1.25-1.5 × HT II. ANT PT/BASE 4.2-6.1 …..7
7ANT PT/BASE 4.9-6.1 (Al. emigrant with sec. rhin. distributed ANT III 60-83, IV 36-42, V 13-22)…..Ovatus insitus
ANT PT/BASE 4.2-5.3. (Al. emigrant with sec. rhin. distributed ANT III 48-60, IV 26-38, V 10-15)…..Ovatus sp. (?malicolens) Korea, BMNH collection)
8 SIPH with a subapical zone of polygonal reticulation. ANT tubercles very well developed. ANT III with 1-10 rhinaria. Body spindle-shaped…..9
SIPH without polygonal reticulation. ANT tubercles weakly developed or absent. ANT III without rhinaria. Body ovate…..10
9SIPH swollen on distal half, proximal to reticulated part. Hairs on ANT III all less than 0.4 × BD III…..Illinoia macgillivrayae
SIPH cylindrical on distal half (sometimes with some constriction of reticulated part). Hairs on ANT III 0.6-1.0 × BD III…..Macrosiphum euphorbiae
10Cauda tongue- or finger-shaped, clearly longer than its basal width. (Al. without a black dorsal abdominal patch).….11
Cauda short, helmet-shaped or triangular, not longer than its basal width in dorsal view. (Al. with an extensive black dorsal abdominal patch)…..20
11Abdomen without any marginal tubercles (MTu). SIPH thin and cylindrical with a small flange, 1.1-1.3 × the very thick cauda which bears 6-7 hairs…..Schizaphis chaenometicola
Abdomen with MTu at least on ABD TERG 1 and 7. SIPH and cauda not as above …..12
12SIPH slightly swollen subapically and constricted before the well-developed flange. MTu on ABD TERG 7 placed posteriodorsally to spiracle, and no larger than spiracular aperture…..Rhopalosiphum oxyacanthae
SIPH tapering from base to flange, which is only moderately developed. MTu on ABD TERG 7 placed posterioventrally to spiracle, and usually larger than the spiracular aperture…..13
13Stridulatory apparatus present. ANT PT/BASE 3.5-5.0…..14
No stridulatory apparatus. ANT PT/BASE less than 3.5…..15
14Longest hairs on ANT III 12-27 μm long, 0.5-1.0 × BD III. Longest hairs on hind tibia up to 60 μm long, less than 0.6 × HT II. Cauda with 10-26 hairs (rarely more than 20). BL often less than 2 mm…..Aphis (Toxoptera) aurantii
Longest hairs on ANT III 29-64 μm long, 1.5-2.0 × BD III. Longest hairs on hind tibia up to 80-110 μm long, 0.7-1.0 × HT II. Cauda with 19-54 hairs (rarely less than 25). BL usually more than 2 mm….. Aphis (Toxoptera) citricidus
15Dorsal abdomen almost wholly covered by an extensive solid black sclerite. Cauda black and usually bearing 4-7 hairs…..Aphis craccivora
Dorsal abdomen without an extensive solid black sclerite. Cauda if black then usually with more hairs…..16
16Femoral hairs mostly much shorter than trochantro-femoral suture…..17
Femoral hairs long and fine, many exceeding length of trochantro-femoral suture …..18
17SIPH 1.3-2.5 × the pale or dusky cauda, which bears 4-8 hairs. R IV+V 1.1-1.4 × HT II. Dorsal abdomen without dark markings…..Aphis gossypii
SIPH and cauda both similarly dark, SIPH being 0.7-1.1 × cauda, which bears 7-17 hairs. R IV+V 0.7-0.9 × HT II. Dorsal abdomen usually with dark markings …..Aphis spiraephaga
18ABD TERG 7 and 8 with dark transverse bands, and at least some dark spinopleural markings on abdomen anterior to SIPH…..Aphis fabae
No dark dorsal abdominal markings…..19
19MTu usually present on ABD TERG 2-4. Cauda with 10-19 hairs. R IV+V more than 120 mm…..Aphis pomi
MTu usually absent from ABD TERG 2-4. Cauda with 7-15 hairs (rarely more than 12). R IV+V less than 120 mm…..Aphis spiraecola
20 Spiracles large and rounded. Abdomen with MTu irregularly present, always smaller than spiracular apertures. (Al.with 13-46 rhinaria on ANT III and 0-15 on IV) …..Brachycaudus helichrysi
Spiracles reniform, not large. Abdomen with MTu on most segments, larger than spiracular apertures. (Al. with ANT III and basal part of IV swollen with numerous large rhinaria; 40-60 on III and 18-30 on IV) …..Dysaphis sp. (Japan; Stroyan, 1985 and BMNH collection)
ChaerophyllumApiaceae
Chaerophyllum aromaticum Aphis fabae; Cavariella aegopodii; Dysaphis chaerophylli;
Hyadaphis foeniculi; Macrosiphum gei; Myzus persicae
Ch. aureumAphis fabae; Aulacorthum solani;
Cavariella aegopodii, theobaldi;
Dysaphis caucasica, chaerophyllina; Hyadaphis foeniculi;
Macrosiphum gei
Ch. bulbosum (incl. ssp. prescotti) Aphis brohmeri, fabae;
Cavariella aegopodii, archangelicae, pastinacae;
Dysaphis brachycyclica, chaerophylli, chaerophyllina, flava;
Hyadaphis coriandri, foenicuili, galaganiae;
Macrosiphum gei
Ch. hirsutumAphis fabae, gossypii, solanella; Aulacorthum solani;
Cavariella aegopodii, pastinacae, theobaldi;
Dysaphis brachycyclica, chaerophylli; Hyadaphis foeniculi;
Macrosiphum gei; Myzus ornatus, persicae;
[Semiaphis dauci]
Ch. maculatumDysaphis chaerophyllina
Ch. prescotti see bulbosum
Ch. roseumMyzus persicae
Ch. sylvestreCavariella aegopodii; Macrosiphum euphorbiae, gei
Ch. temulentum = Ch. temulum
Ch. temulumAphis fabae; Cavariella aegopodii, pastinacae;
Dysaphis [apiifolia], brachycyclica, chaerophylli, [crataegi];
Macrosiphum gei; Semiaphis anthrisci
Ch. villarsiiMacrosiphum gei

Key to apterae on Chaerophyllum:-

1ABD TERG 8 with a backwardly directed process above cauda …..Cavariella spp. (use couplets 2-14 of key to apterae on Angelica)
No supracaudal process…..2
2 ANT tubercles low or absent …..3
ANT tubercles well developed, greatly exceeding height of middle of front of head in dorsal view…..12
3SIPH very short, only 0.4-0.6 × cauda, and flangeless …..Semiaphis anthrisci
SIPH more than 0.8 × cauda, with a distinct flange…..4
4Cauda helmet-shaped, not longer than its basal width in dorsal view…..5
Cauda tongue-shaped, much longer than its basal width…..8
5ANT III with short blunt hairs maximally 12-13 mm long, 0.6-0.7 × BD III. R IV+V 1.5-1.6 × HT II…..Dysaphis caucasica*
ANT III with pointed hairs maximally 22-74 mm long, 1.1-3.1 × BD III. R IV+V 1.1-1.35 × HT II…..6
6ABD TERG 8 with 4-6 hairs (very rarely 7), and cauda with 4-5 hairs (rarely 6). Marginal tubercles (MTu) usually absent from ABD TERG 6 …..Dysaphis chaerophyllina*
ABD TERG 8 with 5-16 hairs; if less than 8 then MTu are usually present on ABD TERG 6. Cauda with 4-13 hairs…..7
7Hairs on ANT III are maximally 47-67 mm long, 2.1-3.1 × BD III…..Dysaphis chaerophylli
Hairs on ANT III are maximally 22-42 mm long, 1.1-1.9 × BD III …..Dysaphis flava or brachycyclica
8 SIPH gradually tapering, 0.8-2.1 × cauda, which bears 4-31 hairs…..9
SIPH swollen, 0.6-1.3 × cauda, which bears 5-7 hairs…..11
9Cauda distinctly paler than SIPH, and bearing 4-8 hairs…..Aphis gossypii
Cauda as dark as SIPH, and bearing 11-31 hairs…..10
10Cauda with 11-24 hairs. ABD TERG 8 with 2-5(-7) hairs. ABD TERG 2-6 bearing a total of 0-3 small MTu…..Aphis fabae
Cauda with 20-31 hairs. ABD TERG 8 with 5-12 hairs. ABD TERG 2-6 bearing a total of 5-9 often rather large MTu…..Aphis brohmeri
11SIPH clavate, 1.7-3.2 × R IV+V, 1.6-2.8 × HT II and 0.9-1.3 × cauda…..Hyadaphis foeniculi
SIPH swollen basally, 0.95-1.7 × R IV+V, 0.9-1.35 × HT II and 0.6-0.8 × cauda…..Hyadaphis galaganiae (or coriandri)
12 SIPH with a subapical zone of polygonal reticulation. ANT tubercles smooth, divergent, bearing pointed hairs…..13
SIPH without polygonal reticulation. ANT tubercles spiculose or scabrous, steep-sided or apically convergent, bearing blunt hairs…..14
13Longest hair on ABD TERG 8 is 38-63 µm, 0.6-1.4 × ANT BD III. Anterior half of subgenital plate usually (77%) with only 2 hairs (18% with 3, 5% with 4-6 hairs) …..Macrosiphum euphorbiae
Longest hair on ABD TERG 8 is 66-106 µm, 1.4-2.0 × ANT BD III. Anterior half of subgenital plate with 2-11 hairs, usually (77%) with 4-8 hairs …..Macrosiphum gei
14ANT III usually with 1-2 rhinaria. Inner faces of ANT tubercles spiculose, approximately parallel…..Aulacorthum solani
ANT III without rhinaria. Inner faces of ANT tubercles scabrous, convergent apically …..15
15Dorsum with a pattern of dark intersegmental ornamentation. ANT PT/BASE 1.7-2.8. SIPH tapering, with a slight “S”-curve…..Myzus ornatus
Dorsum without dark intersegmental ornamentation. ANT PT/BASE 2.8-4.7. SIPH slightly clavate…..Myzus persicae
Chaetochloa see SetariaPoaceae
Chaetotropis see PolypogonPoaceae
Chalcas see Murraya Rutaceae
ChamaebatiaRosaceae
Chamaebatia foliolosa Ericaphis voegtlini; Macrosiphum euphorbiae

Couplet for separating apterae of these two species:-

(Both species have smooth head and SIPH with subapical polygonal reticulation.)

R IV+V 1.5-1.8 × HT II. Median frontal tubercle developed similarly to ANT tubercles so that front of head is W-shaped in dorsal view. SIPH slightly swollen, pale basally and dark distally. Cauda with 4-6 hairs …..Ericaphis voegtlini
R IV+V 0.8-1.2 × HT II. Median frontal tubercle undeveloped, ANT tubercles well developed, with divergent inner faces. SIPH tapering/cylindrical, pale or only dusky towards apices. Cauda with 8-12 hairs…..Macrosiphum euphorbiae
ChamaebatiariaRosaceae
Chamaebatiaria millefolium Acyrthosiphon sp. near pseudodirhodum (BMNH collection),
Illinoia sp. (BMNH collection)

(Both the species in the BMNH collection are from USA, California, White Mts., Cotton Wood Basin, 9, 600 ft, leg. P Rude)

Couplet for separating apterae of the two species from Chamaebatiaria in the BMNH collection:-

(Both have smooth head with divergent ANT tubercles, and mainly pale SIPH and cauda.)

SIPH c.1.1 × cauda which bears c.14 hairs. ANT PT/BASE c.6, PT 2.8-3.0 × SIPH. R IV+V 0.9-1.0 × HT II….. Acyrthosiphon sp. near pseudodirhodum
SIPH 2.3-2.8 × cauda which bears 8-10 hairs. ANT PT/BASE 3.3-3.9, PT 0.45-0.6 × SIPH. R IV+V 1.6-2.0 × HT II…..Illinoia sp. (BMNH collection)
ChamaecristaFabaceae
Chamaecrista absus Aphis (Toxoptera) citricidus
Ch. mimosoidesAphis craccivora, gossypii
Ch. nomaneAphis craccivora

Use key to polyphagous aphids.

Chamaecyparis Cupressaceae
Chamaecyparis lawsoniana Cinara (Cedrobium) laportei;
Cinara (Cupressobium) cupressi, louisianensis, tujafilina;
Illinoia morrisoni
Ch. obtusa[Cinara ozawai]; Stomaphis hirukawai
Ch. thyroides[Cinara sp. (Leonard, 1968: 269, 340)]

Key to aphids on Chamaecyparis:-

1 ANT PT/BASE more than 1. SIPH long and tubular, swollen distally …..Illinoia morrisoni
ANT PT/BASE less than 1. SIPH are broad, hairy cones…..2
2 Rostrum about 1.7 × BL…..Stomaphis hirukawai
Rostrum shorter than BL…..3
3 Antenna 5-segmented. Dorsal hairs of aptera club-shaped, ornamented with numerous barbules…..Cinara (Cedrobium) laportei
Antenna 6-segmented. Dorsal hairs normal, pointed ….. Cinara (Cupressobium) spp.
(use couplets 5-7 of key under Cupressus)

(N.B. Other aphids whose more normal hosts are Cedrus, Cupressus ot Tsuga may occasionally colonise Chamaecyparis, so it may be advisable to look also at the keys to aphids on those plants.)

ChamaecytisusFabaceae
Chamaecytisus albus = Cytisus albus
Ch. austriacus = Cytisus austriacus
Ch. candicans = Genista monspessulana
Ch. heuffelii = Cytisus austriacus ssp. heuffelii
Ch. palmensis = Cytisus proliferus
Ch. proliferus = Cytisus proliferus
Ch. ratisbonensis = Cytisus ratisbonensis
Ch. ruthenicus = Cytisus ruthenicus
Ch. scrobiszewskii = Cytisus graniticus
Ch. spinosus = Cytisus spinosus
Ch. supinus = Cytisus hirsutus
Ch. zingeri = Cytisus ruthenicus var. zingeri

Use key to apterae on Cytisus.

ChamaedaphneEricaceae
Chamaedaphne calyculata Macrosiphum nasonovi
ChamaedoreaArecaceae
Chamaedorea costaricana Cerataphis brasiliensis
Ch. elegansRhopalosiphum padi

Use key to apterae on palms under Calamus.

ChamaegeronAsteraceae
Chamaegeron oligocephalus Uroleucon tschuensis
ChamaemelumAsteraceae
Chamaemelum fuscatum Brachycaudus helichrysi; Macrosiphum euphorbiae;
Myzus persicae
Ch. mixtum = Cladanthus mixtus
Ch. nobileAphis craccivora, fabae; Brachycaudus cardui, helichrysi;
Macrosiphoniella sanborni, tanacetaria; Myzus persicae

Use key to apterae on Anthemis.

Chamaenerion see EpilobiumOnagraceae
ChamaerhodosRosaceae
Chamaerhodos erecta Szelegiewicziella chamaerhodi
Chamaerops Arecaceae
Chamaerops humilis Cerataphis brasiliensis

Use key to apterae on palms under Calamus.

ChamaespartiumFabaceae
Chamaespartium sagittale = Genista sagittalis
Ch. tridentatum Aphis craccivora
ChamaesyceEuphorbiaceae
Chamaesyce maculata = Euphorbia maculata
ChamelauciumMyrtaceae
Chamelaucium uncinatum Aphis gossypii, spiraecola; Myzus persicae

Use key to polyphagous aphids.

ChamissoaAmaranthaceae
Chamissoa altissima Aphis craccivora, gossypii; Macrosiphum euphorbiae

Use key to polyphagous aphids.

ChamomillaAsteraceae
Chamomilla recutita = Matricaria chamomilla
Ch. suaveolens = Matricaria matricarioides
Ch. tenuifolia = Tripleurospermum tenuifolium
ChangiumApiaceae
Changium smyrnoides Semiaphis heraclei
ChaptaliaAsteraceae
Ch. comptonioides Aphis aurantii, gossypii, spiraecola
Ch. montanaAphis aurantii, gossypii; Uroleucon ambrosiae
Ch. nutansAphis [coreopsidis], gossypii
Chaptalia sp.Brachycaudus helichrysi

Use key to polyphagous aphids.

ChardiniaAsteraceae
Ch. orientalisAphis craccivora