HOST LISTS AND KEYS FOR EACH PLANT GENUS

(in alphabetical order)

Rha-Ror

Rhabdadenia

Rhabdosia

Rhacomitrium

Rhagadiolus

Rhamnella

Rhamnus

Rhamphicarpa

Rhaphiolepis

Rhapis

Rhaponticum

Rheum

Rhigozum

Rhinanthus

Rhinopetalum

Rhipogonum

Rhizomnium

Rhizophora

Rhodiola

Rhodobryum

Rhodococcum

Rhododendron

Rhodomyrtus

Rhodotypos

Rhoicissus

Rhus

Rhynchelytrum

Rhynchosia

Rhynchosinapis

Rhynchospora

Rhynchostegium

Rhytidiadelphus

Rhytidophyllum

Ribes

Richardia

Ricinus

Riedlea

Ritchiea

Robinia

Rochea

Rodriguezia

Roegneria

Roellia

Roemeria

Roepera

Roldana

Romneya

Rorippa

RhabdadeniaApocynaceae
Rhabdadenia biflora Aphis gossypii
Rhabdosia error for Rabdosia (see Isodon)Lamiaceae
Rhacomitrium see RacomitriumGrimmiaceae
RhagadiolusAsteraceae
Rhagadiolus hedypnois [Protaphis sp. (Iran: Stary et al. 2000)]
Rh. stellatusHyperomyzus lactucae, picridis;
Uroleucon hypochoeridis, mierae, picridis

Key to apterae on Rhagadiolus:-

1 SIPH pale, markedly swollen, and without polygonal reticulation…..2
SIPH dark, not swollen, with distal zone of polygonal reticulation…..3
2 R IV+V 1.45-1.8 × HT II, with 8-12 accessory hairs …..Hyperomyzus picridis
R IV+V 0.85-1.05 × HT II, with 6-9 accessory hairs …..Hyperomyzus lactucae
3 R IV+V 0.84-1.08 × HT II…..Uroleucon hypochoeridis
R IV+V 1.19-1.84 × HT II…..4
4 R IV+V 0.24-0.32 mm long, 1.50-1.84 × HT II. Marginal sclerites of ABD TERG 2-5 regularly have well-developed marginal tubercles (MTu) …..Uroleucon picridis
R IV+V 0.19-0.25 mm long, 1.19-1.58 × HT II. ABD TERG 2-5 rather irregularly with small MTu (rarely more than 3 in total)…..Uroleucon mierae
Rhamnella Rhamnaceae
Rhamnella franguloides Aphis odinae, [Aphis rhamnellae Shinji 1922];
Machiatiella itadori;

Use key to aphids on Rhamnus.

Rhamnus (including Frangula)Rhamnaceae
Rhamnus alaternus Aphis aurantii, craccivora, frangulae group, gossypii,
nasturtii, spiraecola;
Macchiatiella rhamni
Rh. alnifoliaAphis glycines, nasturtii
Rh. alpina (incl. ssp. fallax) Aphis frangulae, nasturtii; Macchiatiella rhamni
Rh. californicaAphis nasturtii; Macrosiphum rhamni
Rh. carolinianaAphis nasturtii
Rh. catharticaAphis commensalis, craccivora, fabae, frangulae group,
glycines, gossypii, mammulata, nasturtii,
spiraecola, versicolor;
Brachycaudus helichrysi;
Macchiatiella rhamni, rhamni ssp. tarani;
Myzus persicae; Neomyzus circumflexus
Rh. chlorophora = Rh. globosa
Rh. clusii = Rh. alaternus
Rh. coriaceaMacchiatiella rhamni ssp. tarani
Rh. costataAphis nasturtii; Neomyzus circumflexus
Rh. crenataAphis nasturtii; Neomyzus circumflexus
Rh. davuricaAphis frangulae group, glycines, gossypii, nasturtii
Rh. dolichophylla Macchiatiella rhamni ssp. tarani
Rh. erythroxylum Aphis nasturtii; Neomyzus circumflexus
Rh. fallax see Rh. alpina
Rh. frangulaAlder Buckthorn
Aphis frangulae group, glycines, gossypii, nasturtii,
zamorana;
Macchiatiella rhamni
Rh. globosa Aphis nasturtii
Rh. hemsleyanaAphis nasturtii
Rh. imeretinaAphis frangulae group, nasturtii
Rh. japonicaAphis [frangulae group], glycines, gossypii, [mammulata];
Macchiatiella itadori
Rh. koraiensisAphis gossypii
Rh. lanceolataAphis glycines; Macchiatiella rhamni
Rh. leptophyllaAphis nasturtii
Rh. libanoticaAphis craccivora, frangulae group, gossypii, spiraecola
Rh. ludovici-salvatoris Aphis nasturtii
Rh. lycioidesAphis frangulae, nasturtii
Rh. napalensisAphis aurantii, fabae, gossypii, spiraecola;
Aulacorthum rhamni; Greenidea psidii; Myzus ornatus
Rh. palaestinaAphis craccivora, frangulae group, gossypii, spiraecola
Rh. pallasiiAphis frangulae group, iranensis, nasturtii;
Neomyzus circumflexus
Rh. prinoidesAphis gossypii; Aphis (Toxoptera) aurantii
Rh. pumila Aphis nasturtii
Rh. purshianaAphis gossypii, nasturtii; Macchiatiella itadori, rhamni
Macrosiphum rhamni
Rh. saxatilisAphis frangulae group, nasturtii; Neomyzus circumflexus
Rh. ×spathulifolia Aphis nasturtii; Neomyzus circumflexus
Rh. tinctoriaDyer’s Buckthorn
Aphis mammulata, nasturtii
Rh. triquetraAphis gossypii
Rh. ussuriensisAphis frangulae group
Rh. utilisAphis nasturtii, [utilis]
Rh. virgataAphis rhamnifila
Rhamnus spp.Dysaphis microsiphon; Greenidea heeri;
[Myzakkaia verbasci]

Key to Rhamnus-feeding species (apterae viviparae except fundatrices):-

1 SIPH with numerous long hairs…..2
SIPH without hairs…..3
2 R IV+V 1.8-2.4 × HT II…..Greenidea psidii
R IV+V 1.2-1.75 × HT II…..Greenidea heeri
3Cauda very broadly rounded, less than 0.5× basal width. Dorsal abdomen usually with distinctive black markings…..4
– Cauda helmet, tongue or finger-shaped, 0.6 or more × its basal width. Dorsal abdomen with or without dark markings…..5
4 SIPH black. Dorsal abdomen with an extensive solid black patch. R IV+V 1.15-1.28 × HT II…..Macchiatiella itadori
SIPH pale. Dorsal abdomen with dark patch broken centrally or in midline, often on ABD TERG 3-4 (-5) only and sometimes absent. R IV+V 1.0-1.15 × HT II…..Macchiatiella rhamni
5 SIPH very small, conical, shorter than their basal width. Cauda helmet-shaped, shorter than its basal width…..Dysaphis microsiphon
SIPH tubular, longer than their basal width. Cauda tongue or finger-shaped, or bluntly triangular, usually at least as long as its basal width…..6
6 Head spiculose…..7
Head smooth…..10
7 Dorsal abdomen with a large dark roughly horseshoe-shaped patch (fig. 121I)…..Neomyzus circumflexus
Dorsal abdomen without a large horseshoe-shaped patch…..8
8 ANT III with a small secondary rhinarium near base. Antennal tubercles with inner faces almost parallel. R IV+V 1.25-1.40× HT II. SIPH straight, tapering, dark at least on distal half. Cauda also dark. (Alata with dark transverse bars on dorsal abdomen)…..Aulacorthum rhamni
ANT III without any rhinaria. Antennal tubercles strongly convergent. R IV+V 0.09-1.18 × HT II. SIPH slightly swollen or curved outwards distally. SIPH and cauda mainly pale. (Alata with a black dorsal abdominal patch) …..9
9 Dorsal abdomen with an intersegmental pattern of dark spots and flecks. ANT PT/BASE 2.5 or less. SIPH tapering with shallow S-curve, not swollen distally …..Myzus ornatus
– Dorsal abdomen without dark intersegmental markings. ANT PT/BASE more than 3. SIPH slightly swollen on distal half…..Myzus persicae
10 Antennal tubercles well-developed, divergent. ANT PT/BASE more than 6. ANT III with 1-2 secondary rhinaria near base. SIPH pale, with subapical polygonal reticulation, 0.3 or more × BL…..Macrosiphum rhamni
Antennal tubercles weakly developed. ANT III without rhinaria. ANT PT/BASE less than 6. SIPH pale or dark without subapical polygonal reticulation, less than 0.2 × BL …..11
11 Stridulatory ridges present on abdominal sternites 5 and 6, and a row of peg-like hairs on hind tibia…..12
– No stridulatory apparatus…..13
12 SIPH much shorter than (0.4-0.6×) cauda (fig. 121O). ANT PT/BASE 2.5-3.0…..Aphis odinae
SIPH usually longer than (0.9-1.5×) cauda (figs 121 P, Q). ANT PT/BASE 3.5-5.0….. Aphis (Toxoptera) aurantii
13 Longest hairs on ANT III longer than basal diameter of segment…..14
– Longest hairs on ANT III shorter than basal diameter of segment…..16
14 Femora dark at least distally. ABD TERG 7 and 8 with dark cross bands, and more anterior tergites with some dark segmental and intersegmental markings …..Aphis fabae
Femora pale or dusky. ABD TERG 7 and 8 without or with only faint cross-bands, and more anterior tergites without any dark markings…..15
15 Pronotum and ABD TERG 1-4 and 7 with extremely large, hemispherical marginal tubercles. SIPH 1.5-2.0 × cauda and 4-7 × their width at midpoint …..Aphis mammulata
Marginal tubercles of normal size on ABD TERG 1 and 7, and absent from ABD TERG 2-4. SIPH 0.9-1.2 × cauda, and 1.5-3.0 × their width at midpoint …..Aphis commensalis
16 ABD TERG 1-4 and 7 with large, hemispherical marginal tubercles …..Aphis versicolor
Marginal tubercles of normal size on ABD TERG 1 and 7, and smaller or absent on ABD TERG 2-4…..17
17 SIPH and cauda both pale, or SIPH dark only towards apices. (Alata with 8-18 secondary rhinaria on ANT III, 1-6 on IV and 0-2 on V) …..Aphis nasturtii
SIPH dark, cauda pale or dark…..18
18 Dorsal abdomen almost wholly covered by an extensive solid black sclerite (fig. 121N)…..Aphis craccivora
Dorsal abdomen mainly membranous…..19
19 Cauda dark with 11-24 hairs (rarely less than 12). Femora dark at least distally. ABD TERG 7 and 8 with dark cross bands, and more anterior tergites often with some dark markings…..Aphis fabae (or solanella)
Cauda pale or dark, with 4-15 hairs (rarely more than 12). Femora pale or dark. Dorsal abdomen without dark markings…..20
20Cauda as dark as SIPH with 7-15 (usually 8-12) hairs and a slight constriction at or just proximal to midpoint…..21
Cauda paler than SIPH, with or without a constriction, or if as dark as SIPH then 4-7 hairswith only …..22
21 Femora with basal half pale, gradually becoming darker on distal half. Marginal tubercles (MTu) usually only on prothorax and ABD TERG 1 and 7 …..Aphis spiraecola
Femora blackish except at base. Small MTu usually present on ABD TERG 2-5 as well as on 1 and 7…..Aphis zamorana
22 Dorsal cephalic hairs finely pointed, 35-45 µm long. Hind femur with some ventral hairs more than 45 µm long, exceeding diameter of trochantro-femoral suture. Cauda almost as dark as SIPH, with about 6 hairs…..Aphis rhamnifila
Dorsal cephalic hairs blunt, less than 30 µm long. Hairs on hind femur all not exceeding diameter of trochantro-femoral suture. Cauda usually paler than SIPH, with 4-10 hairs…..23
23 Head and ANT I-V pale, only ANT VI dusky. SIPH usually more than 0.2 × BL. Cauda much paler than SIPH, often with a midpoint constriction, and bearing 8-10 hairs…..Aphis glycines
Head and at least ANT I, II and last segment (V or V) dusky or dark. SIPH usually less than 0.2 × BL. Cauda often dusky, not contrasting with SIPH, unconstricted, bearing 4-9 hairs…..24
24 ANT PT/BASE 1.0-1.9 (the majority of specimens have 5-segmented antennae). SIPH short and thick, 1.5-3.5 × longer than their midlength width. Cauda short and bluntly triangular…..Aphis iranensis
ANT PT/BASE 2.0-3.0 (most specimens of normal size have 6-segmented antennae). SIPH 3.3-8.0 × longer than their midlength width. Cauda tongue- or finger-shaped….. Aphis frangulae group (incl. gossypii, rhamnicola)
RhamphicarpaOrobanchaceae
Rhamphicarpa fistulosa Aphis gossypii
RhaphiolepisRosaceae
Rhaphiolepis indica Aphis craccivora, pomi, spiraecola;
Illinoia macgillivrayae; Myzus persicae;
Nippolachnus micromeli;
Rhopalosiphoninus staphyleae; Sinomegoura photiniae
Rh. japonicaAphis gossypii
Rh. umbellataAphis spiraecola; Nippolachnus micromeli;
Sinomegoura photiniae
Rh. vinifera[Cerataphis brasiliensis]

Key to apterae on Rhaphiolepis:-

1 ANT less than 0.5 × BL, with PT/BASE 0.45-0.75. Body elongate, pale, and body and appendages densely clothed in long fine hairs. SIPH poriform …..Nippolachnus micromeli
ANT more than 0.5 × BL, with PT/BASE more than 1.5. Body oval or spindle-shaped, sparsely hairy. SIPH tubular…..2
2 SIPH dark, 1.2-1.3 × the long, rather acutely-pointed cauda, which bears 10-18 hairs. Head markedly spiculose on ventral surface, but not dorsally, and with well-developed, broadly divergent ANT tubercles…..Sinomegoura photiniae
Without that combination of characters…..3
3 SIPH 2.4-2.7 × cauda, with swollen section on distal half, narrowing to a subapical region with 4-5 rows of polygonal reticulation. Head smooth with inner faces of ANT tubercles divergent…..Illinoia macgilllivrayae
Without that combination of characters…..4
4 SIPH and cauda both black. Cauda finger-like, usually with a midway constriction. Dorsal abdomen without dark markings…..5
SIPH and cauda pale or dark, but if both black then cauda is tongue-shaped without a constriction, and dorsal abdomen has dark markings …..go to key to polyphagous aphids
5 Marginal tubercles (MTu) present on ABD TERG 2-4. Cauda with 10-19 hairs (rarely less than 13). R IV+V more than 130μm long……Aphis pomi
MTu absent from ABD TERG 2-4. Cauda with 7-15 hairs (rarely more than 12). R IV+V less than 120μm long……Aphis spiraecola
RhapisArecaceae
Rhapis excelsaAphis gossypii; Sinomegoura citricola
Rh. javanicaAstegopteryx rhapidis
Rhaponticum Asteraceae
Rhaponticum carthamoides = Stemmacantha carthamoides
Rh. nitidum[Brachyunguis harmalae]
Rh. repens[Acyrthosiphon ilka, pisum];
Aphis craccivora; Dysaphis acroptilidis;
Nasonovia ribisnigri;
Protaphis anuraphoides, [carthami], iliensis, [terricola];
Uroleucon acroptilidis, compositae, [jaceae]
Rh. serratuloidesProtaphis anuraphoides

Key to apterae on Rhaponticum and Stemmacantha:-

1 Cauda finger-like, much longer than its basal width…..2
Cauda helmet-shaped or conical, not longer than its basal width…..6
2 SIPH pale or dark, if entirely dark then without subapical polygonal reticulation …..3
SIPH dark with polygonal reticulation on distal 0.25-0.33 of length…..4
3 Thoracic spiracles much larger than abdominal ones. Dorsal abdomen with paired dark pleural markings. ANT PT/BASE 7.0-11.4…..Nasonovia ribisnigri
Thoracic and abdominal spiracles all small. Dorsal abdomen with or without dark markings. ANT PT/BASE less than 7…..go to key to polyphagous aphids
4 Cauda pale, with 7-11 hairs. First tarsal segments with 3 hairs …..Uroleucon mongolicum
Cauda dark, with 9-20 hairs. First tarsal segments with 5 hairs…..5
5 ANT PT/BASE 3.8-4.7. R IV+V 1.0-1.1 × HT II…..Uroleucon acroptilidis
ANT PT/BASE 5.1-7.3. R IV+V 1.1-1.4 × HT II …..Uroleucon compositae (or gobonis)
6 ANT PT/BASE 1.5-1.8. Cauda with 5 hairs…..Dysaphis acroptilidis
ANT PT/BASE 0.55-1.1. Cauda with 16-20 hairs…..7
7 ANT PT/BASE 0.85-1.1. ANT III 1.8-2.5 × PT…..Protaphis anuraphoides
ANT PT/BASE 0.55-0.75. ANT III 2.7-3.8 × PT…..Protaphis iliensis
RheumPolygonaceae
Rheum australeAphis fabae
Rh. compactumAphis fabae, solanella
Rh. emodii = Rh. australe
Rh. franzenbachii = Rh. rhabarbarum
Rh. maximowiczii Aphis rheicola; Brachyunguis rhei; Dysaphis emicis
Rh. moorcroftianum = Rh. spiciforme
Rh. nutans = Rh. compactum
Rh. officinaleAphis fabae; Capitophorus hippophaes ssp. javanicus;
Macrosiphum euphorbiae
Rh. palmatumAphis fabae, rumicis; Myzus ornatus
Rh. rhabarbarum Aphis acetosae, craccivora, fabae, fabae ssp. mordvilkoi,
gossypii, rumicis, solanella;
Dysaphis rumecicola;
Macrosiphum euphorbiae, stellariae;
Myzus ascalonicus, [certus], ornatus, persicae
Rh. rhaponticumAphis fabae, rheicola, rumicis, solanella;
Macrosiphum euphorbiae; Myzus persicae
Rh. spiciformeAphis fabae
Rh. tataricumAphis craccivora, fabae;
[Brachycaudus rumexicolens];
Dysaphis emicis, rumecicola
Rh. undulatum = Rh. rhabarbarum
Rheum spp. (and cultivars) [Aphis frangulae ssp. beccabungae];
Aulacorthum solani, [solani ssp. orientale];
Dysaphis radicola

Key to apterae on Rheum:-

1Cauda very broadly rounded, hardly developed, much less than half as long as its basal width in dorsal view. SIPH small, broad-based, conical, shorter than their basal widths…..Brachycaudus rumexicolen
Cauda helmet-, tongue- or finger-shaped. SIPH usually longer than their basal width …..2
2 Cauda helmet-shaped, not longer than its basal width in dorsal view. Paired spinal tubercles (STu) present on head and (at least) ABD TERG 8…..3
Cauda tongue- or finger-shaped, more than 1.2 × its basal width in dorsal view. STu absent from head, and usually from ABD TERG 8…..5
3 Paired STu on head and ABD TERG 8, or 7 and 8, absent from ABD TERG 1-6. Hairs on ANT III and ABD TERG 1-5 shorter than ANT BD III. SIPH 2.0-2.5 × cauda…..Dysaphis radicola
Single or paired STu present on most or all segments from head to ABD TERG 8. Longest hairs on ANT III and ABD TERG 1-5 much longer than ANT BD III. SIPH 1.5-2.2 × cauda…..4
4 Hairs on ANT III and ABD TERG 1-5 fine-pointed, those on ANT III longer than 45 μm, 2 or more × ANT BD III. R IV+V 1.55-1.70 × HT II …..Dysaphis rumecicola
Hairs on ANT III and ABD TERG 1-5 often with blunt apices, those on ANT III being all less than 45 μm long, less than 2 × BD III. R IV+V 1.3-1.6 × HT II …..Dysaphis emicis
5 ANT PT/BASE c. 1.0…..Brachyunguis rhei*
ANT PT/BASE more than 1.5…..6
6 Dorsal hairs, or at least those on head and ABD TERG 8, long, thick and capitate, arising from tuberculate bases. R IV+V rostrate, i.e. with R V extended into a short, beak-like process…..Capitophorus hippophaes (ssp. javanicus)
Dorsal hairs not long, thick and capitate, not on tuberculate bases. R IV+V not rostrate…..7
7 ANT tubercles weakly developed or undeveloped. Prothorax, ABD TERG 1 and 7 with marginal tubercles (MTu)…..8
ANT tubercles well developed. Prothorax and ABD TERG 1 and 7 without MTu …..12
8Dorsal abdomen with an extensive solid black sclerite centred on ABD TERG 4-5. Cauda black like SIPH, tongue-shaped, rather pointed and bearing 4-7 hairs …..Aphis craccivora
Dorsl abdomen with or without dark markings, but without an extensive solid black sclerite. Cauda pale or dark, but if black then with more than 9 hairs…..9
9 Well-developed MTu present on all or most of ABD TERG 2-4 as well as 1 and 7…..Aphis acetosae
Small MTu only sporadically present on ABD TERG 2-4…..10
10 Cauda paler than SIPH and bearing 4-8 hairs. Dorsal abdomen without dark markings…..Aphis gossypii
SIPH and cauda both dark, cauda with 10-24 hairs. Dorsal abdomen with or without dark markings…..11
11 ANT III darker on distal half, and IV entirely dusky/dark. Dorsal abdomen usually with dark cross-bands including an especially broad one on ABD TERG 6 between SIPH…..Aphis rumicis
ANT III entirely pale, IV pale or darker distally. Dorsal abdomen with cross-bands absent or only well developed on ABD TERG 7 and 8…..Aphis fabae group (including solanella, and possibly rheicola*)
12 Head smooth, and inner faces of ANT tubercles smooth and divergent. SIPH with a subapical zone of polygonal reticulation…..13
Head spiculose, inner faces of ANT tubercles scabrous or spiculose and parallel or apically convergent. SIPH without polygonal reticulation …..go to key to polyphagous aphids
13 Femora usually with a dark spot or patch near apices. 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
RhigozumBignonaceae
Rhigozum obovatum Myzus persicae
Rhinanthus (including Alectorolophus) Orobanchaceae
Rhinanthus alectorolophus [Acyrthosiphon pisum]; Aphis fabae;
Brachycaudus helichrysi; Hyperomyzus luteus, rhinanthi;
Myzus alectorolophi
Rh. alpinus = Rh. riphaeus
Rh. angustifoliusAphis fabae; Brachycaudus persicae;
Hyperomyzus rhinanthi; Myzus cerasi
Rh. borbasii (incl. ssp. songaricus) Aphis craccivora; Hyperomyzus rhinanthi
Rh. crista-galli = Rh. glacialus
Rh. glaberAphis fabae
Rh. glacialis Brachycaudus helichrysi; Hyperomyzus rhinanthi
Rh. hirsutusHyperomyzus rhinanthi
Rh. major = Rh. serotinus
Rh. minorAphis fabae; Brachycaudus helichrysi;
Hyperomyzus rhinanthi
Rh. riphaeus Hyperomyzus rhinanthi
Rh. serotinus (incl. ssp. aestivalis) Aphis sibirica; Brachycaudus persicae;
Hyperomyzus luteus, rhinanthi; Myzus cerasi
Rh. songaricus = Rh. borbasii ssp. songaricus
Rh. spadiceusBrachycaudus helichrysi; Hyperomyzus rhinanthi
Rh. subalpinusBrachycaudus helichrysi;
[Hyperomyzella erratica of Weis 1955 (= Hyperomyzus
rhinanthi?)]
Rh. vernalis = Rh. serotinus ssp. aestivalis
Rhinanthus spp.[Myzus padellus]

Key to apterae on Rhinanthus:-

1 Dorsal abdomen with a large black quadrate central patch. SIPH black and markedly swollen over distal 0.75 of length. ANT III with 25-64 rhinaria …..Hyperomyzus rhinanthi
Without that combination of characters…..2
2 SIPH markedly swollen on distal half, with maximum diameter greater than R IV+V or ANT BASE VI…..Hyperomyzus luteus*
SIPH not swollen…..3
3 Head spiculose with well-developed scabrous ANT tubercles. SIPH very coarsely imbricated (scaly)…..4
Head not spiculose, ANT tubercles absent or weakly developed. SIPH smooth or with normal imbrication…..5
4 Dorsum with extensive dark sclerotisation. SIPH more than 7 × longer than their width at midlength. Cauda with 6-9 hairs…..Myzus cerasi
Dorsum sclerotic but not dark in mounted preparations. SIPH less than 6 × longer than width at midlength. Cauda with 4-6 hairs…..Myzus alectorolophi (or M. padellus)
5 Cauda tongue-shaped, longer than its basal width, with 7-24 hairs. Spiracular apertures reniform. ABD TERG 7 with marginal tubercles (MTu) ……6
Cauda helmet-shaped, not longer than its basal width, with 4-8 hairs. Spiracular apertures large and rounded. ABD TERG 7 without MTu……7
6 SIPH 0.4-0.9 × cauda, which has a constriction at midlength. ANT III 0.6-1.2 × cauda…..Aphis sibirica
SIPH 0.8-1.8 × cauda, which does not have a midlength constriction. ANT III 1.2-1.9 × cauda…..Aphis fabae group (incl. A. solanella)
7 Dorsum with an extensive dark sclerotic shield. SIPH black, imbricated, more than 2 × cauda……Brachycaudus persicae
Dorsum pale. SIPH pale, smooth-surfaced, less than 2 × cauda…..Brachycaudus helichrysi
Rhinopetalum see Fritillaria Liliaceae
RhipogonumRhipogonaceae
Rhipogonum scandens Aulacorthum solani; Myzus persicae;
Neomyzus circumflexus; Sitobion miscanthi

Key to apterae on Rhipogonum:-

SIPH dark with a distal zone of polygonal reticulation. R IV+V less than 0.8 × HT II…..Sitobion miscanthi
Without that combination of characters…..go to key to polyphagous aphids
RhizomniumMniaceae
Rhizomnium magnifolium [Clydesmithia canadensis]; [Pachypappa sacculi]
Rhizomnium sp. [Prociphilus xylostei]

Try key to moss-feeding aphids under Polytrichum.

RhizophoraRhizophoraceae
Rhizophora mangle Aphis gossypii
RhodiolaCrassulaceae
Rhodiola atropurpurea Aphis gossypii
Rh. bupleuroides Aphis sedi
Rh. gelida [Brachycaudus cerasicola]
Rh. heterodonta Aphis sedi
Rh. roseaAphis fabae, sedi; Brachycaudus sedi
Rh. semenovii [Brachycaudus cerasicola]

Key to apterae on Rhodiola:-

1 Cauda broadly rounded, much shorter than its basal width in dorsal view. SIPH stump-like…..Brachycaudus sedi
Cauda tongue-shaped, longer than its basal width. SIPH tubular…..2
2 Cauda black with 11-24 hairs. Dorsal abdomen with dark cross-bands on ABD TERG 7 and 8, and some dark markings anterior to SIPH. Femora with many fine hairs longer than trochantro-femoral suture…..Aphis fabae
Cauda pale or dark with 4-8 hairs. Dorsal abdomen with or without dusky cross-bands on ABD TERG 7 and 8, usually without any dark markings anterior to SIPH. Femoral hairs all much shorter than trochantro-femoral suture…..3
3 ANT PT/BASE 1.6-2.3. SIPH 0.9-1.4 × cauda, which bears 4-6 hairs and is usually rather dark, only a little paler than SIPH…..Aphis sedi
ANT PT/BASE 2.1-3.2. SIPH 1.3-2.5 × cauda, which bears 4-8 hairs and is usually pale/dusky, markedly paler than SIPH…..Aphis gossypii
RhodobryumBryaceae
Rhodobryum roseum Muscaphis escherichi
Rhodococcum see VacciniumEricaceae
Rhodococcum vitis-idaea = Vaccinium vitis-idaea
Rhododendron (including Azalea, Ledum) Ericaceae
Rhododendron albiflorum = Azaleastrum albiflorum
Rh. albrechtiiVesiculaphis caricis
Rh. arboreumAphis gossypii; Brachycaudus helichrysi;
Chaetomyzus rhododendri, [Chaetomyzus sp. (Dutta &
Gautam 1993);
Ericolophium holsti, rhododendri, takahashii;
Indiaphis crassicornis; [Macrosiphoniella spinipes];
Myzus ornatus, persicae; Sinomegoura rhododendri
Rh. calendulaceum Illinoia lambersi
Rh. californicum = Hymenanthes californica
Rh. campanulatum Myzus brevisiphon
Rh. campylocarpum [Aulacorthum perillae]; Ericolophium takahashii;
Myzus brevisiphon, persicae
Rh. canescens Illinoia rhokalaza
Rh. catawbiense ×metternichii Illinoia lambersi
Rh. cunninghami Illinoia lambersi
Rh. dauricumVesiculaphis cephalata, kongoensis
Rh. decorumIllinoia lambersi
Rh. degronianum(?) Neoamphorophora ledi
Rh. diversipilosum Neoamphorophora ledi
Rh. ferrugineumAphis remaudieri
Rh. flavum = Rh. luteum
Rh. formosanumEricolophium taiheisanum
Rh. groenlandicum Illinoia paqueti, pianwae
Rh. hirsutumIllinoia lambersi
Rh. indicum = Rh. simsii
Rh. japonicum(?)Illinoia lambersi
Rh. japonoheptamerum Neoamphorophora ledi
(ssp. japonoheptamerum)
Rh. kaempferiVesiculaphis caricis
Rh. kesselringiiIllinoia lambersi
Rh. lasiostylumEricolophium itoe
Rh. luteumIllinoia dzhibladzeae, lambersi
Rh. macrophyllum = Hymenanthes macrophyllum
Rh. maximum = Hymenanthes maxima
Rh. maxwelliiIllinoia lambersi
Rh. molleIllinoia azaleae, lambersi; Macrosiphum euphorbiae
Rh. moriiEricolophium holsti
Rh. mucronulatum Vesiculaphis caricis, cephalata, kongoensis
(incl. ssp. sichotense)
Rh. obtusumVesiculaphis caricis
Rh. oldhamiiSinomegoura rhododendri
Rh. palustre (= Ledum palustre) Illinoia azaleae; Neoamphorophora ledi
Rh. ponticumIllinoia lambersi
Rh. przelwaskiiEricolophium ninguidum
Rh. reticulatumEricolophium itoe; Vesiculaphis kongoensis
Rh. rhodoraIllinoia azaleae ssp. rhododendronia
Rh. schlippenbachii Vesiculaphis caricis
Rh. sichotense = Rh. mucronulatum ssp. sichotense
Rh. simsii[Chaetomyzus rhododendrophila (alata only)];
Ericolophium alpiginiae, nigripunctatum, rectisiphon;
Illinoia azaleae, lambersi, rhododendri;
Rostratusaphis rhododendronitos; Vesiculaphis caricis
Rh. sublanceolatum Illinoia lambersi
Rh. viscosumIllinoia rhokalaza
Rh. yedoenseVesiculaphis caricis
Rhododendron spp. Acyrthosiphon [rubi], Acyrthosiphon sp. (Norway, BMNH
collection, leg. C. Stenseth);
[Aiceona retipennis];
Aphis fabae, [kurosawai], nerii, odinae, spiraecola;
[Chaitophorus clarus Tseng and Tao];
Ericolophium ovalifolii, tianchiense;
[Eulachnus thunbergii (Wilson)]; [Eutrichosiphum sp.];
[Hillerislambersia darjeelingi]; [Hyperomyzus nabali];
Indiaphis indica, rostrata, Indiaphis sp.(W Bengal; BMNH
colln, leg. A.N. Basu);
Indomasonaphis anaphalidis; [Lipaphis erysimi];
[Macrosiphum rosae]; Neomasonaphis inulae;
Rhododendraphis tuatayae;
[Rhopalosiphum rufiabdominale]; [Trichaitophorus aceris];
[Uroleucon nigrotuberculatum, sonchi];
Vesiculaphis grandis, rhododendri;
Wahlgreniella nervata

Key to apterae on Rhododendron:-

1 SIPH with a subapical zone of reticulation (at least 3-4 rows of rather large polygonal cells, occupying distal 0.06-0.2 of total length). ANT III usually with 1 or more rhinaria on basal part. ANT tubercles well developed, their inner faces divergent…..2
SIPH without reticulation; sometimes with interconnected transverse striae near apex, but no polygonal cells. ANT III with or without rhinaria. ANT tubercles variably developed or undeveloped…..9
2 Tergum almost wholly dark sclerotic. Cauda dusky/dark. ANT III and most of IV pale…..Illinoia dzhibladzeae
Tegum pale or if pigmented then Cauda pale and ANT III and IV dusky/dark …..3
3 ANT hairs very short and blunt, the longest on III much less than 0.5 × BD III …..4
Longest hairs on ANT III more than 0.5 × BD III…..5
4 R IV+V less than 0.14 mm long, 1.1-1.45 × HT II, and bearing 8-12 accessory hairs. Second tarsal segments without spinules on the imbrications (Fig.46a). HT II more than 1.5 × longer than maximum diameter of swollen part of SIPH…..Illinoia azaleae (incl. ssp. rhododendronia)
R IV+V more than 0.14 mm long, 1.4-1.9 × HT II, and bearing 15-23 accessory hairs. Second tarsal segments with spinules on the imbrications (Fig.46b). HT II less than 1.5 × longer than maximum diameter of swollen part of SIPH…..Illinoia lambersi
5 SIPH entirely dark. ANT III-V rather evenly dusky/dark …..Illinoia rhokalaza
SIPH pale at least on basal part, although often dark distally. ANT III –V mainly pale, darker at apices…..6
6 R IV+V 0.8-1.0 × HT II, with 7-10 accessory hairs. First tarsal segments with 3 hairs. Second tarsal segments without spinules on the imbrications …..Macrosiphum euphorbiae
R IV+V 1.05-1.90 × HT II, with 14-38 accessory hairs. First tarsal segments with (4-)5 hairs. Second tarsal segments with (sometimes minute) spinules on the imbrications …..7
7 R IV+V 0.21-0.24 mm long, 1.05-1.45 × HT II, which has long thin spinules on the imbrications, and HT I is also spinulose (Fig.46c)…..Illinoia paqueti
R IV+V 0.125-0.20 mm long, 1.65-1.90 × HT II, which has very small spinules on the imbrications, and no distinct spinules on HT I…..8
8 ANT shorter than BL. R IV+V 0.125-0.155 mm long, with 14-20 accessory hairs. SIPH rather thick, usually without a thinner section on basal half (Fig.46d) …..Illinoia rhododendri
ANT longer than BL. R IV+V 0.175-0.20 mm long, with c. 30 accessory hairs. SIPH long and thin with some distal swelling so that there is a thinner section on basal half (Fig.46e)…..Illinoia pinawae
9 SIPH conspicuously warty or nodulose throughout length…..10
SIPH smooth, or with normal, spiculose or denticulate imbrication, or warty only towards apices…..15
10 ANT PT/BASE 1.7-2.8. ANT tubercles well-developed, with inner faces apically covergent…..Myzus ornatus
ANT PT/BASE less than 1.5. ANT tubercles not projecting forward beyond middle of front of head in dorsal view…..11
11 SIPH clavate…..Vesiculaphis rhododendri*
SIPH not clavate, i.e., without a narrower section on basal half…..12
12 BL more than 3.5 mm. R IV+V 1.8-2.0 × HT II. HT I with 3 hairs (sense peg present). (ANT III of alata with 82-85 rhinaria) …..Vesiculaphis grandis
BL less than 2.5 mm. R IV+V 1.0-1.4 × HT II. HT I with 2 hairs (sense peg absent). (ANT III of alata with 19-54 rhinaria)…..13
13 Head warty with small blunt nodules dorsally along posterior margin, and frontal part produced into 3 large lobes. (Alata with anterior dorsal cephalic hairs a little longer than ANT BD III. Cauda tongue-shaped, at least 1.5 × its basal width. SIPH more than 0.75 × head width across eyes)…..Vesiculaphis cephalata
Head scabrous with many minute spicules in rows dorsally along posterior margin, and frontal part produced into a ledge, with median tubercle as a low swelling beneath it. (Alata with anterior dorsal cephalic hairs shorter than ANT BD III. Cauda triangular, less than 1.5 × its basal width. SIPH less than 0.75 × head width across eyes)…..14
14 (Alata) Forewing with media once-branched. Dorsal abdomen without any dark cross-bands. ANT III smooth, with 28-54 rhinaria. R IV+V 0.6-1.2 × ANT BASE VI…..Vesiculaphis caricis
(Alata) Forewing with media twice-branched. Abdomen with dark cross-bands on ABD TERG 3-5. ANT III imbricated, with 19-23 rhinaria. R IV+V 0.4-0.5 × ANT BASE VI…..Vesiculaphis kongoensis
15 Most dorsal hairs arising from rounded, broad-based processes…..16
Dorsal hairs not arising from broad-based processes…..18
16 Dorsal processes scabrous, those on ABD TERG 5 and 6 being longer than their basal widths, bearing hairs much shorter than height of processes (Fig.46f). SIPH markedly clavate. Cauda with 5-6 hairs. First tarsal segments with 3 hairs…..Chaetomyzus rhododendri
Dorsal processes smooth, hemispherical, all much shorter than their basal widths, bearing long thickish hairs, longer than heights of processes, and with expanded apices (Fig.46g). SIPH clavate or cylindrical. Cauda with 24-60 hairs. First tarsal segments with 5 hairs…..17
17 SIPH distinctly clavate. Cauda with 35-60 hairs …..Indomasonaphis anaphalidis
SIPH cylindrical or only very slightly swollen on distal half. Cauda with 24-34 hairs…..Indomasonaphis inulae
18 SIPH clavate or at least slightly swollen (i.e. with narrower section on basal half) …..19
SIPH cylindrical or tapering…..24
19 ANT PT/BASE 0.5-0.7. R IV+V extremely long, 3.3-3.7 × HT II and bearing 32-42 accessory hairs…..Rostratusaphis rhododendronitos
ANT PT/BASE 1.0-6.8. R IV+V less than 3 × HT II, with less than 30 accessory hairs…..20
20 ANT PT/BASE 1.0-1.3 (estimated, because only alatae have been described). First tarsal segments with 5 hairs….. “Ericolophium alpigeniae*
ANT PT/BASE 1.4-6.8. First tarsal segments with (2-)3 hairs…..21
21 Head densely spiculose, with inner faces of ANT tubercles apically convergent. ANT PT/ BASE 2.8-4.5…..Myzus persicae
Head smooth, with inner faces of ANT tubercles divergent. ANT PT/BASE 1.4-2.4 or 5.2-6.8…..22
22 ANT PT/BASE 5.2-6.8. Tergum entirely pale…..Wahlgreniella nervata
ANT PT/BASE 1.4-2.4. Tergum with some dark markings…..23
23 ANT III without rhinaria. Tergum mainly membranous, with only small sclerites anterior to SIPH and dark cross-bands on posterior tergites. R IV+V less than 1.3 × HT II, with 2-4 accessory hairs…..Neoamphorophora ledi
ANT III with 3-8 rhinaria, spaced out over distal 0.5-0.7 of length. Tergum mainly dark sclerotic. R IV+V more than 1.9 × HT II, with c.25 accessory hairs…..Rhododendraphis tuatayae
24 Second tarsal segments with spinules on the imbrications, at least ventrally …..25
Second tarsal segments without spinules on the imbrications…..36
25 R IV+V 1.5-1.7 × HT II, with 16-21 accessory hairs. Cauda with 10-15 hairs…..Ericolophium holsti
R IV+V 0.8-1.7 × HT II, with 2-6 accessory hairs. Cauda with 4-12 hairs …..26
26 First tarsal segments with 5 hairs. Cauda with 8-12 hairs. R IV+V 0.8-0.9 × HT II…..Ericolophium ninguidum
First tarsal segments with 3 hairs. Cauda with 4-8 hairs. R IV+V 0.9-1.7 × HT II …..27
27 Longest hairs on ABD TERG 1-3 more than 24 μm, 1-6 × ANT BD III …..28
Longest hairs on ABD TERG 1-3 less than 20 μm, shorter than ANT BD III …..32
28 Longest hairs on ABD TERG 1-3 only 25-30 μm, 1.0-1.2 × ANT BD III, with blunt apices. R IV+V 1.5-1.7 × HT II. ANT PT/BASE 2.2-3.0…..Indiaphis indica
Longest hairs on ABD TERG 1-3 more than 50 μm, 1.5-6 × ANT BD III, with pointed apices. Other characters not in above combination…..29
29 R IV+V 1.6-1.7 × HT II. (ANT 5-segmented, with PT/BASE 1.1-1.2) …..Indiaphis rostrata (fundatrices?)
R IV+V 0.9-1.5 × HT II …..30
30 ANT 0.9-1.5 × BL, with PT/BASE c.3. SIPH more than 4 × longer than their width at midlength…..Ericolophium takahashii*
ANT only c.0.5 × BL, and PT/BASE 1.0-1.9. SIPH stout, less than 3 × longer than their width at midlength (e.g. Fig.46h)…..31
31 R IV+V more than 0.15 mm long, longer than cauda. ANT tubercles undeveloped. ANT PT/BASE 1.5-1.9…..Indiaphis crassicornis
R IV+V less than 0.12 mm long, shorter than cauda. ANT tubercles low but evident. ANT PT/BASE 1.0-1.1…..Indiaphis sp.
(?fundatrix; W Bengal, BMNH colln, leg. AN Basu)
32 R IV+V 1.3-1.6 × HT II. SIPH dark…..Ericolophium itoe (partim)
R IV+V 0.6-1.1 × HT II. SIPH pale at least basally…..33
33 R IV+V 0.6-0.9 × HT II…..34
R IV+V 1.0-1.1 × HT II…..35
34 Tergum with a dark sclerotic patch extending from ABD TERG 3-6. Dorsal hairs pointed…..Ericolophium nigripunctatum*
Dorsal abdomen without a dark patch. Dorsal hairs blunt …..Ericolophium rectisiphon*
35 Tergum pale. SIPH c.2.5-2.6 × cauda…..Ericolophium ovalifolii
Tergum entirely dark brown. SIPH c. 1.9-2.0 × cauda …..Ericolophium taiheisanum*
36 ANT longer than BL. ANT III with 1-4 rhinaria near base. SIPH entirely pale or with dark apices…..37
ANT shorter than BL. ANT III without rhinaria, and other characters not in above combination…..39
37 Head densely spiculose, with inner faces of ANT tubercles steep-sided, almost parallel…..Aulacorthum solani
Head not spiculose, inner faces of ANT tubercles divergent…..38
38 SIPH strongly tapering to dark apices, 0.7-1.2 × the dark cauda. R IV with 2-4 accessory hairs…..Sinomegoura rhododendri
SIPH almost cylindrical over most of length, entirely pale, 2.0-2.1 × the pale cauda. R IV with 1-16 accessory hairs…..Acyrthosiphon sp. (Norway, BMNH collection, leg. C. Stenseth)
39 ANT tubercles moderately or well developed (if rather low then scabrous, and inner side of ANT I also scabrous). ABD TERG 1 and 7 without marginal tubercles and cauda tongue-shaped, much longer than its basal width…..40
ANT tubercles undeveloped, or weakly developed but not scabrous. Either ABD TERG 1 and 7 have MTu or cauda is helmet-shaped, not longer than its basal width
(Note: specimens running to Aphis solanella may be A. remaudieri Börner – see text)
…..go to key to polyphagous aphids, starting at couplet 15
40 SIPH stout, less than 6.5 × longer than their midlength widths, and almost flangeless (Fig.46i). Second tarsal segments weakly imbricated, almost smooth on distal half (Fig.46j). Hairs on ABD TERG 1-3 maximally 55-85 μm, c.2 × ANT BD III…..Ericolophium rhododendri
SIPH more than 7 × longer than their widths at midlength, with a distinct flange. Second tarsal segments normally imbricated (often with at least traces of spinules on the imbrications). Hairs on ABD TERG 1-3 maximally 20μm, not longer than ANT BD III…..41
41 ANT PT/BASE 2.2-2.4. R IV+V c.1.4 × HT II, with 2 accessory hairs. Cauda with 5-7 hairs…..Ericolophium itoe (partim)
ANT PT/BASE 1.6-1.8. R IV+V 0.75-0.9 × HT II, with 8-14 accessory hairs. Cauda with 10-11 hairs…..Ericolophium tianchiense
RhodomyrtusMyrtaceae
Rhodomyrtus tomentosa Greenidea psidii
Rhodomyrtus sp. (?) Greenidea siamensis

Key to apterae on Rhodomyrtus:-

(Both species have SIPH with numerous long hairs.)

BL 1.3-1.7 mm. SIPH black, darker than dorsal abdominal sclerotisation. (Al. with 7-17 rhinaria on ANT III)….. Greenidea siamensis
BL 1.8-2.6 mm. SIPH not as dark as dorsal abdominal sclerotisation. (Al. with 20-31 rhinaria on ANT III)….. Greenidea psidii
RhodotyposRosaceae
Rhodotypos kerrioides = Rh. scandens
Rh. scandensAphis fabae; Rhopalosiphum rufiabdominale

Use key to polyphagous aphids.

RhoicissusVitaceae
Rhoicissus cuneifolia Sitobion cissi
Rh. tridentata Sitobion cissi
Rhus Sumacs Anacardiaceae
Rh. abyssinicaAphis rhoicola
Rh. ambigua = Toxicodendron orientale
Rh. aromatica = Rh. canadensis
Rh. canadensisCarolinaia rhois
Rh. chinensisChinese Sumac
Aphis aurantii, citricidus, craccivora, odinae;
Chuansicallis chengtuensis;
Kaburagia rhusicola; [Macrosiphum euphorbiae];
[Neobetulaphis pusilla];
Nurudea ibofushi, shiraii, yanoniella;
[Prociphilus oriens]; Schlechtendalia chinensis, peitan;
Rh. crenataAphis gossypii
Rh. dentata Aphis gossypii
Rh. diversiloba = Toxicodendron diversilobum
Rh. glabraSmooth Sumac
Carolinaia rhois; Melaphis asafitchi, rhois
Rh. hirta = Rh. typhina
Rh. hypoleucaAphis odinae; Nurudea zhengii
Rh. japonicaBug-namu, Korean Sumac
Schlechtendalia chinensis
Rh. javanica = Rh. chinensis
Rh. khasianaAphis (Toxoptera) citricidus
Rh. laevigataAphis gossypii
Rh. lanceaAphis gossypii; Myzus persicae
Rh. lucidaAphis gossypii
Rh. magalismontana Melaphis rhois
Rh. nepalensis[Neobetulaphis chaetosiphon]
Rh. pendulinaAphis gossypii; Myzus persicae
Rh. potaniniiKaburagia [ovatirhusicola], rhusicola; Floraphis choui;
[Meitanaphis microgallis]
Rh. punjabensis var. sinica Kaburagia rhusicola;
Meitanaphis elongallis, [flavogallis Tang, 1978];
Floraphis meitanensis; Nurudea yanoniella;
Schlechtendalia chinensis, peitan
Rh. pyroides Aphis gossypii
Rh. radicans = Toxicodendron radicans
Rh. semialata = Rh. chinensis
Rh. sinica = Rh. punjabensis var. sinica
Rh. succedanea = Toxicodendron succedaneum
Rh. sylvestris = Toxicodendron sylvestre
Rh. trichocarpa = Toxicodendron trichocarpum
Rh. trifoliolata = Rh. magalismontana
Rh. trilobataCarolinaia rhois
Rh. typhinaStaghorn Sumac
[Aphis fabae]; Carolinaia rhois; Melaphis asafitchi, rhois
Rh. verniciflua = Toxicodendron vernicifluum
Rh. viminalis = Rh. pendulina
Rh. wallichii[Eutrichosiphum assamense]
Rhus sp.Aphis (Toxoptera) citricidus; [Illinoia spiraeae];
Mollitrichosiphon rhusae; Pseudomegoura magnoliae
Key to aphids on Rhus:-
1 ANT PT/BASE much less than 0.5, with PT short and thick. SIPH absent. Gall formers. (ANT of al. with strap-like, annular secondary rhinaria.)…..2
ANT PT/BASE more than 0.5, with PT thin and elongate. SIPH present, tubular. Free-living aphids. (ANT of al. with rounded or oval secondary rhinaria)…..13
2 (Couplets 3-11 refer to alate migrants from galls)Pterostigma of forewing extending in a curve around tip of wing (fig. 99A) …..3
Pterostigma of normal length, not extending around wing-tip (fig. 99B) …..5
3 Antenna 6-segmented, II-VI each with a single very large rhinarium occupying most of its surface area, in which are scattered many small islands of sclerotized cuticle (fig. 99C)…..Meitanaphis elongallis
Antenna 5-segmented; II-V each with at least partial separation of the sensoriated surface into smaller units (fig. 99D)…..4
4 ANT III longer than base of ANT V…..Schlechtendalia chinensis
ANT III shorter than base of ANT V…..Schlechtendalia peitan*
5 Antenna 6-segmented…..6
Antenna 5-segmented…..9
6 ANT III-VI each with a single large oblong rhinarium occupying most of its surface area (fig. 99E)…..Kaburagia rhusicola
– ANT III-VI with separate, transversely elongate rhinaria…..7
7 Rhinaria on ANT III-VI numerous (usually more than 8 on ANT III), and usually some of them completely ringing the antenna (fig. 99F) …..Melaphis rhois (part; or M. asafitchi – see text)
– Rhinaria on ANT III-VI fewer in number (maximum of 8 on ANT III), never completely ringing the antenna (e.g. fig 99G)…..8
8 ANT III less than 1.5 × IV. Tibiae with short hairs …..Floraphis meitanensis
ANT III more than 1. 5 × IV. Tibiae with long hairs…..Floraphis choui
9 ANT III clearly longer than ANT V, with 10 or more narrow, annular secondary rhinaria (fig. 99H) …..Melaphis rhois (part; or M. asafitchi – see text)
ANT III similar in length to ANT V, with less than 10 broad or narrow secondary rhinaria (figs. 99I-K)…..10
10 ANT IV and V each with a single large rhinarium occupying most of the surface area, enclosing small scattered islands of cuticle (fig. 99I)…..Nurudea ibofushi*
ANT IV and V with one or more separated rhinaria like ANT III…..11
11 ANT IV and V each with only a single small secondary rhinarium proximal to the large primary rhinarium, much smaller than those on ANT III …..Nurudea zhengii*
ANT IV and V with annular rhinaria like those on ANT III…..12
12 Secondary rhinaria on ANT IV and V mostly broad and strap-like, and sometimes joined to form rhinaria longer than width of antenna (fig. 99J)…..Nurudea shiraii
Secondary rhinaria on ANT IV and V all narrow and separate (fig. 99K)…..Nurudea yanoniella
13 SIPH tubular, dark brown, about half of body length and densely clothed in long hairs. (Hind tibiae with about 30 stridulatory (?) ridges on basal 0.6-0.7 of length)….. Mollitrichosiphon rhusae
SIPH shorter and without hairs…..14
14 ANT PT/BASE less than 1. SIPH as small, truncate cones, shorter than basal width. Cauda knobbed, anal plate bilobed…..Chuansicallis chengtuensis
ANT PT/BASE more than 1. SIPH tubular, longer than basal width. Cauda tongue- or finger-like, anal plate entire…..15
15 Stridulatory ridges present ventrolaterally on abdominal sternites 5 and 6, and hind tibia with a row of short, peg-like hairs. Cauda with 10-54 hairs…..Aphis (Toxoptera) spp. and Aphis odinae (use couplets 26-27 of polyphagous aphids key)
No stridulatory ridges nor peg-like hairs on hind tibiae. Cauda with fewer hairs …..16
16 SIPH cylindrical or tapering from base to flange…..17
SIPH swollen at least slightly in middle or on distal half…..19
17 Dorsal abdomen with an extensive black patch…..Aphis craccivora
Dorsal abdomen without an extensive black patch…..18
18 ANT PT/BASE less than 2…..Aphis rhoicola
ANT PT/BASE more than 2…..Aphis gossypii
19 Head capsule smooth or wrinkled, with ANT tubercles weakly developed. SIPH are entirely dark…..Carolinaia rhois
Head capsule scabrous or spiculose, at least ventrally, and ANT tubercles well developed, with steep-sided or apically convergent inner faces. SIPH at least basally pale …..20
20 Antennae and legs mainly dark, SIPH dark distally. ANT III with 1-2 secondary rhinaria near base. Antennal tubercles with inner faces parallel …..Pseudomegoura magnoliae
Antennae, legs and SIPH mainly pale. ANT III without any rhinaria. Antennal tubercles with inner faces convergent…..Myzus persicae
Rhynchelytrum see MelinisPoaceae
RhynchosiaFabaceae
Rhynchosia cytisoides Acyrthosiphon pisum
Rh. minimaAphis craccivora, gossypii; Sitobion nigrinectarium
Rh. nyasicaAphis craccivora
Rh. resinosaSitobion nigrinectarium
Rhynchosia sp. Microparsus rhynchosiae

Key to apterae on Rhynchosia:-

1 ANT tubercles undeveloped or weakly developed. ANT III without rhinaria. ANT PT/BASE 2.0-3.4. ABD TERG 1 and 7 with marginal tubercles (MTu)…..2
ANT tubercles well developed. ANT III with 1-5 small rhinaria near base. ANT PT/BASE 3.0-7.4. ABD TERG 1 and 7 without MTu…..3
2 Dorsal abdomen with an extensive black patch. SIPH and cauda both black…..Aphis craccivora
Dorsal abdomen without any dark sclerotisation. SIPH black, cauda pale or dusky…..Aphis gossypii
3 SIPH somewhat clavate, 0.16-0.21 × BL…..Microparsus rhynchosiae
SIPH long and thin, tapering/cylindrical, more than 0.21 × BL…..4
4 SIPH pale, distally attenuate, without any polygonal reticulation …..Acyrthosiphon pisum
SIPH dark with subapical zone of polygonal reticulation …..Sitobion nigrinectarium
RhynchosinapisBrassicaceae
Rhynchosinapis cheiranthos = Coincya monensis ssp. cheiranthos
Rhynchospora (including Dichromena) Cyperacaeae
Rhynchospora alba Sitobion paludum
Rh. contractaHysteroneura setariae
Rh. cyperoides = Rh. holoschoenoides
Rh. elongata = Rh. uniflora
Rh. holoschoenoides Carolinaia caricis
Rh. marisculusCarolinaia caricis; Hysteroneura setariae
Rh. polyphylla = Rh. contracta
Rh. radicansCarolinaia caricis; Hysteroneura setariae
Rh. rugosaCarolinaia caricis
Rh. setacea (?)Carolinaia caricis
Rh. uniflora Rhopalosiphum maidis
Rhynchospora sp. Rhopalosiphum padi

Key to apterae on Rhynchospora:-

Dorsal abdomen with extensive dark sclerotisation extending without subdivision across all of ABD TERG 1-5, including margins. SIPH black, 1.4-1.9 × cauda, with a distal zone of polygonal reticulation…..Sitobion paludum
Without that combination of characters…..go to key to apterae on Cyperus
Rhynchostegium see EurhynchiumBrachytheciaceae
RhytidiadelphusHylocomiaceae
Rhytidiadelphus loreus Melaphis rhois
Rh. squarrosus[Cryptaphis poae]; Decorosiphon corynothrix;
Jacksonia papillata; Melaphis rhois;
Muscaphis escherichi; [Prociphilus xylostei];
Pseudacaudella rubida

Use key to apterae of moss-feeding aphids under Polytrichum.

RhytidophyllumGesneriaceae
Rhytidophyllum villosulum Aphis spiraecola
Ribes (including Chrysobotrya, Grossularia) Grossulariaceae
Ribes aciculareAphis grossulariae; Eriosoma ulmi;
Hyperomyzus lactucae, pallidus
R. acidumAphis schneideri
R. affineAphis solitaria
R. alpestreAphis fabae
R. alpinumAphis grossulariae, schneideri, triglochinis;
Cryptomyzus [ballotae], galeopsidis, heinzei, korschelti,
rhinanthi; [ribis];
Eriosoma anncharlotteae, [ulmi];
Hyperomyzus lactucae, [luteus], pallidus, picridis,
rhinanthi, zirnitsi;
Nasonovia cynosbati, ribisnigri, vannesii
R. altissimumCryptomyzus ribis
R. ambiguumHyperomyzus lactucae
R. americanumAphis grossulariae
R. atropurpureum = R. petraeum
R. aureumAphis [cornifoliae Fitch (of Gillette 1910)],
[costalis? (see aphidtrek.org)]; fabae,
grossulariae, mimuli, nasturtii, oenotherae, schneideri;
Aulacorthum solani;
Cryptomyzus galeopsidis, korschelti, ribis; Eriosoma ulmi;
Hyperomyzus lactucae, nigricornis, pallidus, picridis,
rhinanthi, ribiellus;
Macrosiphum euphorbiae; Myzus persicae;
Nasonovia cynosbati, houghtonensis ssp. russellae,
ribisnigri
R. bracteosumCryptomyzus ribis; Hyperomyzus lactucae
R. burejenseAphis grossulariae; Cryptomyzus taoi
R. cereumAphis grossulariae, [Aphis (Bursaphis) sp., Washington, USA – see aphidtrek.org] ;
Nasonovia arizonensis (?), cynosbati,
houghtonensis ssp. cerei, grossa, [polemonii]
R. cereum var. inebrians Cryptomyzus galeopsidis, korschelti;
Hyperomyzus lactucae, pallidus, picridis;
Nasonovia ribisnigri
R. ciliatumAphis solitaria
R. cynosbatiCryptomyzus ribis;
(= Grossularia cynosbati) Nasonovia cynosbati, houghtonensis ssp. similis
R. diacanthumAphis grossulariae, schneideri, varians;
Hyperomyzus lactucae
R. distansCryptomyzus korschelti
R. divaricatum (incl. ssp. parishii) Aphis grossulariae; Eriosoma ulmi;
Nasonovia cynosbati, ?vannesii
R. fasciculatum (incl. var. chinense) Aphis grossulariae, triglochinis;
Cryptomyzus taoi; Hyperomyzus lactucae;
[Macrosiphum suguri Shinji (nomen dubium)];
[Sitobion akebiae]
R. fragransAphis grossulariae, triglochinis, varians
R. glacialeCryptomyzus korschelti; Hyperomyzus lactucae;
Nasonovia ribisnigri
R. glandulosum Hyperomyzus nabali; Cryptomyzus ribis
R. glutinosum = R. sanguineum var. glutinosum
R. ×gordonianum Aphis schneideri
R. gracileHyperomyzus nabali; Nasonovia ribisnigri
R. graveolensAphis grossulariae
R. grossularia = R. uva-crispa
R. grossularioides = R. burejense
R. heterotrichumAphis grossulariae, schneideri;
Cryptomyzus korschelti, malkovskii, [ribis];
Hyperomyzus lactucae, pallidus; [Nasonovia alatavica]
R. hirtellumNasonovia houghtonensis ssp. similis, ribisnigri
R. hispidulum = R. spicatum ssp. hispidulum
R. hudsonianum var. petiolare Hyperomyzus petiolaris
R. inebrians = R. cereum var.inebrians
R. inerme Cryptomyzus ribis; Hyperomyzus pallidus;
Nasonovia grossa, houghtonensis ssp. occidentalis,
houghtonensis ssp. russellae, ribisnigri
R. irriguum = R. oxyacanthoides var. irriguum
R. janczewskiiAphis triglochinis; [Cryptomyzus ribis (really korschelti?)];
Eriosoma ulmi
R. japonicumHyperomyzus lactucae
R. komaroviiAphis grossulariae; Hyperomyzus lactucae, pallidus
R. lacustre = Limnobotrya lacustris
R. latifoliumAphis grossulariae; Cryptomyzus ribis
R. laxiflorumAphis oenotherae; Cryptomyzus galeopsidis;
Hyperomyzus lactucae
R. leptanthumAphis oenotherae; Nasonovia cynosbati
R. longiflorum = R. aureum
R. longiracemosum Cryptomyzus ribis
R. lucidum = R. alpinum
R. luridumAphis grossulariae
R. macwiggi (?maximowiczii) Cryptomyzus korschelti
R. magellanicumAphis varians; Cryptomyzus ribis; Hyperomyzus lactucae
R. malvaceumNasonovia cynosbati, ribifolii
R. malvifolium[Cryptomyzus ribis (really korschelti?)]
R. manshuricumAphis grossulariae, schneideri;
Cryptomyzus korschelti, ribis; Hyperomyzus pallidus
R. maximowicziiNasonovia ribisnigri
R. menziesiiHyperomyzus lactucae, pallidus, picridis
(= Grossularia menziesii)
R. meyeriAphis grossulariae, schneideri;
Cryptomyzus korschelti, [multipilosus], ribis,
[transiliensis];
Eriosoma ulmi; Hyperomyzus lactucae, pallidus, picridis;
Nasonovia ribisnigri
R. missourienseCryptomyzus ribis
(= Grossularia missouriensis)
R. montigenumNasonovia cynosbati, ribifolii
R. multiflorumCryptomyzus ribis; Hyperomyzus lactucae
R. nevadaense[Aphis (Bursaphis) sp.]; Hyperomyzus lactucae
R. nigrumAphis [epilobii], fabae, grossulariae, manitobensis, mimuli,
oenotherae, schneideri, triglochinis, varians;
Cryptomyzus galeopsidis, galeopsidis ssp. citrinus,
galeopsidis ssp. dickeri, ribis
Eriosoma ulmi;
Hyperomyzus lactucae, nigricornis, pallidus, petiolaris,
[picridis], rhinanthi, ribiellus;
Nasonovia cynosbati, houghtonensis ssp. similis, ribisnigri
Rhopalosiphoninus ribesinus
R. niveum = R. gracile
R. non-scriptumNasonovia ribisnigri
R. odoratum = R. aureum
R. orientaleCryptomyzus ballotae, korschelti; Nasonovia ribisnigri
R. oxyacanthoides Hyperomyzus lactucae;
Nasonovia houghtonensis ssp. similis, ribisnigri
R. oxyacanthoides Eriosoma ulmi; Hyperomyzus lactucae, pallidus;
var. irriguum Nasonovia ribisnigri
R. oxyacanthoides var. setosum Cryptomyzus korschelti
R. palczewskii = R. spicatum
R. pallidiflorumAphis grossulariae
R. pallidumAphis grossulariae, schneideri; Cryptomyzus ribis
R. parishii = R. divaricatum ssp. parishii
R. petiolare = R. hudsonianum var. petiolare
R. petraeumAphis grossulariae, schneideri;
Cryptomyzus galeopsidis, korschelti, ribis;
Hyperomyzus lactucae, picridis, rhinanthi;
Nasonovia ribisnigri, vannesii
R. pinetorumNasonovia ribisnigri
R. pubescens = R. spicatum
R. quercetorumNasonovia cynosbati
R. rotundifoliumNasonovia ribisnigri
(= Grossularia rotundifolia)
R. rubrumAphis [epilobii], fabae, [gossypii], grossulariae,
schneideri, triglochinis;
Cryptomyzus galeopsidis, galeopsidis ssp. citrinus,
maudamanti, ribis, stachydis;
Eriosoma grossulariae, ulmi;
Hyperomyzus lactucae, pallidus, rhinanthi, zirnitsi;
Nasonovia cynosbati, ribisnigri, vannesii;
Rhopalosiphoninus ribesinus
R. rubrum Aphis oenotherae
var. subglandulosum (?)
R. ruiziiCryptomyzus ribis
R. sachalinenseCryptomyzus ribis
R. sanguineumAphis fabae, grossulariae, schneideri;
Cryptomyzus galeopsidis, korschelti, ribis
Eriosoma anncharlotteae, grossulariae, ulmi;
Hyperomyzus lactucae, pallidus, picridis;
Nasonovia cynosbati, houghtonensis ssp. similis,
muesebecki
R. sanguineum var. glutinosum Nasonovia ribifolii
R. sativumCryptomyzus galeopsidis, ribis; [Myzus ribis Shinji 1922]
R. saxatileAphis grossulariae;
Cryptomyzus korschelti, malkovskii, ribis;
Hyperomyzus lactucae
R. saxosum (= Grossularia saxosa) Nasonovia cynosbati
R. setosum = R. oxyacanthoides var. setosum
R. sinanenseHyperomyzus lactucae;
[Macrosiphum suguri Shinji (nomen dubium)];
[Myzus ribis Shinji 1922]; Nasonovia ribisnigri;
[Prociphilus pini]
R. speciosumAphis oenotherae; Nasonovia cynosbati
R. spicatumAphis grossulariae; Cryptomyzus ribis, stachydis;
Hyperomyzus lactucae
R. spicatum ssp. hispidulum Cryptomyzus ribis; Hyperomyzus lactucae, rhinanthi;
Rhopalosiphoninus ribesinus
R. trifidumCryptomyzus korschelti; Hyperomyzus lactucae, picridis;
Nasonovia ribisnigri
R. tristeAphis grossulariae, schneideri, triglochinis, varians;
Cryptomyzus korschelti; Hyperomyzus lactucae
R. urceolatumCryptomyzus ribis
R. ussurienseHyperomyzus lactucae; Nasonovia ribisnigri
R. uva-crispaAphis [epilobii], fabae, grossulariae, oenotherae,
schneideri, triglochinis, varians;
Aulacorthum solani;
Cryptomyzus galeopsidis, korschelti, ribis;
Eriosoma grossulariae, ulmi;
Hyperomyzus lactucae, [luteus], pallidus, picridis,
rhinanthi, ribiellus;
Nasonovia brachycyclica, cynosbati, houghtonensis,
ribisnigri
R. valdivianumHyperomyzus lactucae
R. vilmorianum (?) Hyperomyzus lactucae
R. viscosissimumNasonovia grossa, houghtonensis ssp. cerei
R. watsonianumAphis grossulariae
(= Grossularia watsoniana)
Ribes spp.Aphis [atromaculata], oenotherae ssp. pacifica, [popovi],
spiraecola, [viburni (= ?fabae)];
Nasonovia arizonensis, [suguri Shinji (= ?cynosbati)]

Key to apterae on Ribes:-

Note: This key is applicable to second generation apterae of host-alternating species of Cryptomyzus, Hyperomyzus and Nasonovia in spring colonies on Ribes; it will not work for fundatrices, except where this morph is specified. It does not include Hyperomyzus luteus, which we have not seen, and for which there is no adequate published description. Couplets 26-38 are based largely on Heie (1979).

For an illustrated key to the common aphids on commercially grown Ribes spp. see Blackman & Eastop (2000).

1 ANT PT/BASE less than 1. ANT V+VI about equal to or shorter than R IV+V. Dorsal wax glands present each consisting of a ring of facets around an undivided central area (most easily seen on head and margins of abdomen). SIPH as pores with sclerotic rims …..2
ANT PT/BASE more than 1.5. No evident wax glands. SIPH tubular…..4
2 Wax glands with a ring of 9-20 small facets, each of diameter less than 0.25 of that of central area. ANT V 0.63-0.87 × ANT VI (incl. PT) …..Eriosoma grossulariae
Wax glands with a ring of 5-10 facets, each of diameter more than 0.33 of that of central area. ANT V 0.86-1.26 × ANT VI (incl. PT)…..3
3 Central area of wax gland defined by a distinct fine dark double line. ANT VI 0.45-0.58 × R IV+V, which is 1.32-1.63 × HT II. Longest apical hair on ANT PT 15-20 μm…..Eriosoma ulmi
Central area of wax gland delimited by a greyish band or single line. ANT VI 0.31-0.45 × R IV+V, which is 1.6-2.0 × HT II. Longest apical hair on ANT PT less than 15 μm…..Eriosoma anncharlotteae
4 Dorsal body hairs with distinctly capitate apices; either at least some of these hairs are long and very thick, more than 2.5 × longer than ANT BD III and with bases at least 2-3 × thicker than those of ventral hairs, or they arise from transverse rows of sclerites …..5
Dorsal hairs with blunt or pointed apices, or if hairs are long and have somewhat expanded apices then they are not much thicker at base than ventral hairs and/or not on transverse rows of pigmented sclerites…..11
5 Dorsal abdomen with sclerites at bases of capitate hairs. SIPH tapering for most of length. Cauda pentagonal, not longer than its basal width …..Cryptomyzus malkovskii*
Dorsal abdomen membranous. SIPH either thin and cylindrical for most of length, or swollen on distal half. Cauda tongue-shaped, usually longer than its basal width …..6
6 R IV+V 1.3-1.6 × HT II, with 5-18 accessory hairs. Longest hair on ANT III shorter than or about equal to (0.5-1.1 X) BD III, usually shorter than longest hair on ANT I, or if similar in length then R IV+V more than 1.4 × HT II with 7-18 accessory hairs…..7
Longest hair on ANT III longer than (1.2-2.1 X) BD III, similar in length to longest hair on ANT I. R IV+V 0.95-1.35 × HT II, with 2-7 accessory hairs…..10
7 ABD TERG 1-4 each with at most 6-12 long capitate hairs (only marginal hairs duplicated), plus some much smaller hairs amongst them. RIV+V with 11-18 accessory hairs. Cauda not longer than its basal width…..Cryptomyzus korschelti
ABD TERG 1-4 each with (10-)12-18 long capitate hairs (spinal hairs often and pleural sometimes duplicated, as well as marginal hairs). R IV+V with 5-14 accessory hairs. Cauda usually a little longer than its basal width…..8
8 ANT PT/BASE 5.9-9.0. R IV+V 1.48-1.75 × HT II …..Cryptomyzus ballotae (or heinzei?)
ANT PT/BASE 9.0-11.5. R IV+V 1.3-1.5 × HT II…..9
9 SIPH cylindrical or only slightly thickened on distal half, 2.5-4 × cauda, which is not constricted at base. R IV with 5-8 accessory hairs…..Crytomyzus ribis
SIPH slightly but distinctly clavate, 4.3-5 × cauda, which is slightly constricted at base. R IV with 9-13 accessory hairs…..Cryptomyzus taoi
10 SIPH cylindrical or only slightly swollen on distal half, 0.13-0.18 × BL, and 1.5-2.4 × cauda…..Cryptomyzus galeopsidis
SIPH distinctly clavate, 0.17-0.20 × BL and 2.3-4 × cauda …..Cryptomyzus maudamanti
11 SIPH slightly to markedly swollen or clavate…..12
SIPH tapering or cylindrical…..25
12 Head spiculose, with inner faces of ANT tubercles steep-sided or apically convergent…..13
Head smooth, with inner faces of ANT tubercles divergent…..14
13 SIPH black and strongly clavate. ANT III with 5-28 rhinaria. Tergum sclerotic, and often dark. SIPH 2.5-3 × the triangular cauda…..Rhopalosiphoninus ribesinus
SIPH pale and only slightly clavate. ANT III without rhinaria. Tergum not sclerotic. SIPH 1.9-2.5 × the tongue-shaped cauda…..Myzus persicae
14 SIPH ornamented with fine imbrications throughout most of length, even on swollen part…..15
SIPH smooth, or with some imbrication basally or apically, but not on swollen part …..18
15 SIPH only slightly swollen on distal half, with maximum width of swollen part 1.05-1.3 × minimum diameter basad…..16
SIPH distinctly clavate, with maximum width of swollen part 1.5-2.6 × minimum diameter basad…..17
16 SIPH 2.4-2.7 × cauda. Apterae with 7-37 secondary rhinaria on ANT III (and alata with 30-43) ….. Hyperomyzus ribiellus (partim)
SIPH 1.5-2.4 × cauda. Apterae with 6-16 secondary rhinaria on ANT III (and alata with 38-63) ….. Hyperomyzus nigricornis
17 R IV+V shorter than HT II…..Hyperomyzus petiolaris
R IV+V longer than HT II…..Hyperomyzus nabali
18 Dorsum with extensive black sclerotic markings, including a black patch on ABD TERG 2-4(-5). SIPH black, spindle-shaped. Cauda black …..Hyperomyzus rhinanthi
Dorsum pale or only with small dark intersegmental markings. SIPH pale, dusky, or dark-tipped, clavate. Cauda pale…..19
19 SIPH 2.9-4.1 × cauda. ANT III with 0-2 rhinaria…..Cryptomyzus stachydis
SIPH 1.3-2.5 × cauda. ANT III with 0-40 rhinaria…..20
20 R IV+V 0.88-1.25 × HT II, and SIPH with maximum width of swollen part less than 2 × minimum width basad. ANT III with 0-14 rhinaria; if present these are usually restricted to basal half…..21
R IV+V 1.2-1.7 × HT II, but if less than 1.3 × then SIPH has maximum width of swollen part more than 2 × minimum width basad. ANT III with 8-40 rhinaria, often extending in an irregular row onto distal half…..24
21ANT III without or sometimes with 1-4 rhinaria. ANT PT/BASE 2.5-4.5 (fund.) …..22
ANT III with (0-)4-12 rhinaria. ANT PT/BASE 4.3-7.7…..23
22 SIPH 1.2-1.9 × ANT PT. R IV+V 0.9-1.01 × HT II. ANT PT/BASE 2.5-3.6(-4.1)…..Hyperomyzus lactucae (fund.)
SIPH 0.6-1.1 × ANT PT. R IV+V 1.0-1.25 × HT II. ANT PT/BASE (3.1-)3.5-4.5…..Hyperomyzus pallidus (fund.)
23 ANT PT/BASE 4.2-5.5(-6.0). R IV+V 0.88-1.0 × HT II. SIPH (1.65-)1.7-2.0 × cauda. (Al. with dark dorsal patch fenestrated)….. Hyperomyzus lactucae
ANT PT/BASE 5.5-7.8. R IV+V 0.99-1.4 × HT II. SIPH 1.45-1.7(-1.83) × cauda. (Al. with solid dark dorsal patch)….. Hyperomyzus pallidus
24 R IV+V 1.2-1.35 × HT II. Maximum width of swollen part of SIPH 2.1-2.6 × minimum width of stem, which is narrower than hind femur at midlength …..Hyperomyzus zirnitsi
RIV+V 1.5-1.7 × HT II. Maximum width of swollen part of SIPH 1.3-1.6 × minimum width of stem, which is thicker than hind femur at midlength …..Hyperomyzus picridis
25 Thoracic spiracular apertures much larger than abdominal ones. ANT III with 0-52 rhinaria…..26
Thoracic spiracular apertures similar in size to abdominal ones. ANT III with 0-10 rhinaria…..39
26 Abdominal spiracular apertures almost circular, not covered with a cowl-like operculum. Cauda usually with 7-9 hairs (1 dorsoapical and 3-4 lateral pairs)…..27
Abdominal spiracular apertures reniform or oval, partially covered by cowl-like opercula. Cauda usually with 5 hairs (1 dorsoapical and 2 lateral pairs), rarely with 4, 6, 7 or 8…..28
27 SIPH imbricated throughout length, 2.4-2.7 × cauda. ANT III with 7-37 rhinaria, not restricted to basal half, and longest hairs 1.0-1.3 × BD III …..Hyperomyzus ribiellus (partim)
SIPH with little or no imbrication except near apices, 1.6-2.2 × cauda. ANT III with 0-18 rhinaria on basal half, and longest hairs 0.7-1.1 × BD III …..Nasonovia ribisnigri
28 Secondary rhinaria tuberculate. Tergum pale…..29
Secondary rhinaria sunken, flat or only very slightly protruding. Tergum pale or dark, or with dark markings…..30
29 R IV+V 2.1-2.9 × HT II, with 20-24 accessory hairs. ANT PT/BASE 3.8-5.0. ANT III with 10-19 rhinaria, and longest hairs 1.2-1.8 × BD III…..Nasonovia muesbecki
R IV+V c.1.4 × HT II, with c. 9-10 accessory hairs. ANT PT/BASE c. 7. ANT III with c.28-32 rhinaria, and longest hairs c 1.0 × BD III…..Nasonovia vannesii
30 SIPH dark, 2.6-3.0 × cauda. Dorsum with an extensive black shield extending from metanotum to ABD TERG 5 or 6, but not extending laterally on abdomen to spiracles and marginal sclerites…..Nasonovia grossa
SIPH pale or dark, 0.9-2.4 × cauda. Dorsum pale or with dark markings, or if with extensive dark pigmentation this includes marginal sclerites…..31
31 SIPH with spinulose imbrication over almost entire length…..32
SIPH almost smooth or wrinkled, but with spinulose imbrication only on distal part …..38
32 SIPH and cauda dark. Dorsal abdomen usually with dark sclerotisation, consisting of dark sclerites or cross-bars or a complete shield extending to marginal sclerites …..33
SIPH pale or dark-tipped, cauda pale. Dorsal abdomen pale or variably sclerotised, but never with an extensive dark area (Nasonovia houghtonensis s.lat.) ….. 34
33 R IV+V 0.13-0.14 mm, 1.5-1.7 × HT II, with 7-12 accessory hairs. Longest hairs on ANT III 1.1-1.5 × BD III. ANT PT/BASE 3.5-3.7. SIPH 0.07-0.11 × BL…..Nasonovia arizonensis
R IV+V 0.15-0.18 mm, 2.0-2.1 × HT II, with 16-18 accessory hairs. Longest hairs on ANT III 1.6-2.0 × BD III. ANT PT/BASE 3.8-4.5. SIPH 0.19-0.27 × BL …..Nasonovia ribifolii
34 SIPH 0.30-0.57 mm long, usually more than 1.5 × cauda. R IV+V 1.8-2.7 × HT II. (Al. with 30-63 rhinaria on ANT III) …..Nasonovia houghtonensis ssp. cerei
SIPH 0.17-0.33 mm long, usually less than 1.5 × cauda. R IV+V 1.4-2.1 × HT II. (Al. with 16-30 rhinaria on ANT III) …..35
35 R IV+V 1.4-1.7 × HT II, with 10-14 accessory hairs.…. Nasonovia houghtonensis ssp. houghtonensis
R IV+V 1.6-2.1 × HT II, with 12-23 accessory hairs…..36
36 R IV+V with 12-13 accessory hairs ….. Nasonovia houghtonensis ssp. occidentalis
R IV+V with 14-23 accessory hairs…..37
37 Prothorax and ABD TERG 2-5 usually with well-developed marginal tubercles (MTu). ABD TERG 3 usually with 4 marginal hairs on each side….. Nasonovia houghtonensis ssp. russellae
MTu usually absent. ABD TERG 3 usually with 2 marginal hairs on each side….. Nasonovia houghtonensis ssp. similis
38 ABD TERG 1-7 usually with a pattern of more-or-less fused dark sclerites or cross-bars. SIPH almost smooth, and dusky or dark, sometimes with paler middle section…..Nasonovia brachycyclica
Dorsal abdomen pale, rarely with rather pale indistinct sclerites. SIPH pale, usually with some imbrication, occasionally dusky or dark…..Nasonovia cynosbati
39 ANT tubercles well developed, with inner faces divergent or almost parallel. ABD TERG 1 and 7 without marginal tubercles (MTu)…..40
ANT tubercles undeveloped or weakly developed. ABD TERG 1 and 7 always with MTu…..42
40 Head spiculose, with steep-sided, almost parallel ANT tubercles. SIPH without polygonal reticulation…..Aulacorthum solani
Head smooth, with inner faces of ANT tubercles divergent. SIPH with subapical polygonal reticulation…..41
41 ANT PT/BASE c.7. R IV+V 1.1-1.2 × HT II …..Macrosiphum bisensoriatum
ANT PT/BASE 5.3-6.2. R IV+V 0.8-1.0 × HT II …..Macrosiphum euphorbiae
42 R IV+V with 3-12 accessory hairs…..43
R IV+V with 2 accessory hairs…..48
43 Hairs on ANT III very long, fine and wavy, the longest of them 1.8-4 × BD III …..44
Hairs on ANT III straight or curved, not fine and wavy, maximally 1-2 × BD III ……46
44 SIPH 0.13-0.23 mm long, 0.08-0.10 × BL, 0.8-1.0 × cauda …..Aphis manitobensis
SIPH 0.23-0.38 mm long, 0.12-0.25 × BL, and 1.0-2.2 × cauda…..45
45 ABD TERG 2-5 as well as 1 and 7 with well-developed marginal tubercles (MTu)…..Aphis schneideri
ABD TERG 2-5 only sporadically with small MTu…..Aphis varians
46 Marginal tubercles (MTu) present at least on some of AND TERG 2-6…..Aphis grossulariae
MTu usually absent from ABD TERG 2-6…..47
47 ANT III usually with 1-8, and IV with 0-2, rhinaria, on distal half of segment; these are of bursiform type, i.e. sunk in pits, with small irregular-shaped openings. Longest hairs on ABD TERG 8 usually less than 55 μm. Dorsal cuticle distinctly reticulated. HT I with 2 hairs (no sense peg)…..Aphis solitaria
ANT III and IV without rhinaria. Hairs on ABD TERG 8 rarely less than 55 μm long. Dorsal cuticle not reticulated. HT I with 3 hairs…..Aphis oenotherae
48 SIPH and cauda pale or dusky, SIPH sometimes dark-tipped…..49
SIPH and cauda black…..51
49 ANT PT/BASE 1.8-3.0. SIPH 0.9-1.6 × cauda. longest hairs on ANT III 0.4-0.7 × BD III…..Aphis nasturtii
ANT PT/BASE 1.1-1.8. SIPH 0.7-1.3 × cauda. Longest hairs on ANT III 0.7-1.2 × BD III…..50
50 SIPH 1.5-2.0 × longer than their basal width, shorter than ANT PT, and also shorter than cauda. (Secondary rhinaria in al. III 9-20, IV 4-6, V 0)…..Aphis mimuli
SIPH 2.0-3.5 × longer than their basal width, longer than ANT PT and often longer than cauda. (Secondary rhinaria in al. III 25-60, IV 9-25, V 7-17) …..Aphis triglochinis
51 SIPH 0.75-1.1 × ANT III and 1.8-2.7 × ANT BASE VI. ANT PT 0.27-0.46 mm, and ANT PT/BASE 2.1-3.8 (mostly 2.4-3.6). Cauda not constricted near midlength and bearing 11-24 hairs. ABD TERG 7 and 8 with dark bands, and dark dorsal markings also usually present anterior to SIPH. (Al. with 10-23 secondary rhinaria on ANT III) …..Aphis fabae
SIPH 1.1-1.45 × ANT III and 2.8-3.4 × ANT BASE VI. ANT PT 0.22-0.29 mm, and ANT PT/BASE 2.1-2.6. Cauda usually clearly constricted near midlength and bearing 6-15 (usually 9-11) hairs. Abdomen without any dark markings. (Al. with 4-12 secondary rhinaria on ANT III)…..Aphis spiraecola
Richardia Kunth. see Zantedeschia Araceae
Richardia L. Rubiaceae
Richardia pilosa = R. scabra
R. scabraAphis gossypii, spiraecola; Myzus ascalonicus, ornatus

Use key to polyphagous aphids.

RicinusEuphorbiaceae
Ricinus communisCastor Oil Plant
Aphis fabae, gossypii, spiraecola; [Brachycaudus cardui];
[Chromaphis juglandicola]; Macrosiphum euphorbiae;
Myzus ornatus, persicae; Neomyzus circumflexus

Use key to polyphagous aphids.

Riedlea see MelochiaMalvaceae
RitchieaCapparidaceae
Ritchiea sp.Aphis gossypii
Robinia Fabaceae
Robinia luxurians Aphis craccivora
R. neomexicanaAppendiseta robiniae
R. pseudoacaciaBlack Locust
Acyrthosiphon caraganae, gossypii, pisum;
Aphis [craccae], craccivora, craccivora ssp.
pseudoacaciae, fabae, gossypii, solanella, spiraecola;
Appendiseta robiniae; Aulacorthum solani;
[Lachnus tropicalis]; Macrosiphum euphorbiae;
Myzus persicae;
[Eotrama orientalis (Narzikulov 1962)];
[Tinocallis zelkowae]
R. viscosaAphis craccivora

Key to aphids on Robinia:-

1 All viviparae alate, with cauda knobbed, anal plate bilobed. Secondary rhinaria on ANT III transversely elongate. ANT PT/BASE about 0.5. SIPH short, truncated cones with a single short hair attached at base…..Appendiseta robiniae
Apterous viviparae normally present. Cauda tongue or finger-shaped, anal plate entire. Secondary rhinaria round or oval. ANT PT/BASE more than 2. SIPH tubular, without attached hair…..2
2 Antennal tubercles well-developed, broadly divergent, smooth. SIPH long, pale, tapering from a broad base, without supabical reticulation…..3
Antennal tubercles weakly developed or, if well-developed, convergent and scabrous. SIPH dark or pale, if pale then slightly swollen on distal half or with subapical reticulation….. go to key to polyphagous aphids
3SIPH tapering, not attenuate distally, thicker than hind tibia at midlength…..Acyrthosiphon caraganae
SIPH thin and attenuate distally, thinner than hind tibia at midlength …..4
4 SIPH 0.33-0.50 × BL and 2.5-3.5 × cauda…..Acyrthosiphon gossypii
SIPH 0.20-0.36 × BL and 1.2-1.8 × cauda…..Acyrthosiphon pisum
Rochea see CrassulaCrassulaceae
RodrigueziaOrchidaceae
Rodriguezia sp.Sitobion luteum
Roegneria see ElymusPoaceae
RoelliaBryaceae
Roellia roelliiMyzodium modestum

Use key to apterae of moss-feeding aphids under Polytrichum.

RoemeriaPapaveraceae
Roemeria sp.Acyrthosiphon ilka
RoeperaZygophyllaceae
Roepera crenata (?) Macrosiphum euphorbiae
RoldanaAsteraceae
Roldana heracleifolia Uroleucon ambrosiae, mexicanum
R. petasitis Aphis gossypii; Aulacorthum solani;
Brachycaudus helichrysi; Macrosiphum euphorbiae;
Myzus persicae

Use key to apterae on Senecio.

RomneyaPapaveraceae
Romneya coulteri Aulacorthum solani
Rorippa (including Radicula)Brassicaceae
Rorippa amphibia Aphis fabae, gossypii, nasturtii, triglochinis;
Brevicoryne brassicae; Lipaphis erysimi;
Myzus ascalonicus, persicae; Neomyzus circumflexus
R. aquaticaAphis frangulae, nasturtii, triglochinis
R. × armoracioides Myzus persicae
R. atrovirensMyzus ascalonicus
R. austriacaAphis nasturtii, [ spiraephaga], triglochinis;
Lipaphis erysimi
R. dubiaAphis craccivora; Macrosiphum euphorbiae
R. heterophylla = R. dubia
R. hispida = R. palustris
R. humifusa = R. madagascariensis
R. indicaAphis craccivora, gossypii, nasturtii;
Lipaphis pseudobrassicae;
Myzus ascalonicus, ornatus, persicae;
Neotoxoptera oliveri; Pseudomegoura magnoliae
R. islandicaAphis craccivora, nasturtii, triglochinis;
Lipaphis erysimi, pseudobrassicae
R. kerneriAphis nasturtii
R. madagascariensis Lipaphis pseudobrassicae
R. microphylla = Nasturtium microphyllum
R. nasturtiumAphis nasturtii; Lipaphis pseudobrassicae; Myzus persicae
R. nasturtium-aquaticum = Nasturtium officinale
R. obtusa = Rorippa teres
R. officinalis = Nasturtium officinale
R. palustrisAphis craccivora, fabae, gossypii, nasturtii, roripae,
spiraecola;
Lipaphis erysimi
R. portoricensisAphis spiraecola; Myzus persicae
R. sinuataPemphigus populitransversus
R. sublyrata = Rorippa dubia
R. sylvestris[Acyrthosiphon pisum];
Aphis fabae, gossypii, mizutakarashi, nasturtii, triglochinis;
Brevicoryne brassicae; Lipaphis erysimi;
Myzus ascalonicus, ornatus, persicae
R. teres Aphis mimuli

Key to apterae on Rorippa:-

1 ANT PT/BASE less than 0.5. SIPH absent. Wax pore-plates on posterior abdomen..…Pemphigus populitransversus
ANT PT/BASE more than 1.0. SIPH present. No wax pore-plates…..2
2 ANT tubercles absent or weakly developed, or if rather well developed then median frontal tubercle is also similarly developed, so that front of head is convex, straight or sinuate in dorsal view. ABD TERG 1 and 7 with or without marginal tubercles (MTu) …..3
ANT tubercles well developed, so that there is a frontal sinus. ABD TERG 1 and 7 never with MTu…..13
3 SIPH slightly to distinctly swollen in middle, or on distal half…..4
SIPH tapering or cylindrical, with no trace of swelling…..7
4 SIPH clavate, i.e. with narrow section on basal half. Dorsal cuticle ornamented with spinules arranged in polygons…..Rhopalosiphum nymphaeae
SIPH with narrowest part just proximal to flange. Dorsal cuticle without spinulose ornamentation…..5
5 ANT III more than 2 × SIPH, which are 0.6-0.8 × cauda. ABD TERG all with large paired dark sclerites which may be joined medially to form broad cross-bands …..Brevicoryne barbareae of David & Hameed 1975, nec Nevsky
ANT III 1.2-1.7 × SIPH, which are 1.3-1.6 × cauda. ABD TERG 2-4 usually without dark markings (except intersegmental ones) in mounted preparations…..6
6 ANT III + PT together 1.95-2.5 × SIPH (90% of specimens less than 2.4 ×)…..Lipaphis erysimi
ANT III + PT together 2.1-3.2 × SIPH (90% of specimens more than 2.4 ×)…..Lipaphis pseudobrassicae
7 SIPH dark…..8
SIPH pale or dusky, sometimes dark-tipped…..10
8 Dorsal abdomen without dark markings. Cauda with 8-14 hairs. (Al. with 2-6 rhinaria on ANT IV)…..Aphis mizutakarashi*
Without that combination of characters…..9
9 Head spiculose or nodulose. SIPH 2.7-3.0 × cauda which is about as long as its basal width, bears 4-6 hairs and has a swollen basal part and narrower apical part …..Myzodium mimulicola
Without that combination of characters…..go to key to polyphagous aphids, starting at couplet 24
10 ANT 5-segmented, with ANT PT/BASE 3.5-4.5. ANT III usually with 1-9 rhinaria…..Aphis roripae
ANT usually 6-segmented. ANT PT/BASE 1.1-3.0. ANT III usually without rhinaria …..11
11 ANT PT/BASE 1.8-3.0. SIPH 0.9-1.6 × cauda. Longest hairs on ANT III 0.4-0.7 × BD III…..Aphis nasturtii
ANT PT/BASE 1.1-1.8. SIPH 0.7-1.3 × cauda. Longest hairs on ANT III 0.7-1.2 × BD III …..12
12 SIPH 1.5-2.0 × longer than their basal width, shorter than ANT PT, and also shorter than cauda. (Secondary rhinaria in al. III 9-20, IV 2-6, V 0)…..Aphis mimuli
SIPH 2.0-3.5 × longer than their basal width, longer than ANT PT and often longer than cauda. (Secondary rhinaria in al. III 25-60, IV 9-25, V 7-17) …..Aphis triglochinis
13 SIPH and cauda entirely black. Dorsum with extensive dark pigmentation. Head densely spiculose, with ANT tubercles scabrous and apically convergent …..Myzus cerasi
Without that combination of characters…..go to key to polyphagous aphids