C_HOSTS_Sap_Sen – Blackman & Eastop's Aphids on the World's Plants

*Sapindus*	Sapindaceae
*Sapindus mukorossi* = S. saponaria
*S. saponaria*	Aphis gossypii; Tinocallis insularis
*Sapindus* sp.	[Greenidea bucktonis]

*Sapium*	Euphorbiaceae
*Sapium japonicum* (= Neoshirakia japonica)	Japanese Tallow Tree
	Pseudomegoura magnoliae
*S. sebiferum* Roxb. (= Triadica sebifera)	Chinese Tallow Tree
	Aphis odinae

Use key to polyphagous aphids.

*Saponaria*	Caryophyllaceae
*Saponaria boissieriana*	Myzus cymbalariae, persicae
*S. officinalis*	Aulacorthum solani; Brachycaudus lychnidis; Brachycolus cucubali; Myzus ascalonicus, persicae
Saponaria sp.	Aphidura ornatella (as bahratia)

Use key to apterae on Silene.

*Saposhnikovia*	Apiaceae
*Saposhnikovia divaricata*	Aphis gossypii; Cavariella japonica

*Saraca*	Fabaceae
*Saraca declinata*	Aphis (Toxoptera) aurantii
*S. indica*	Aphis (Toxoptera) aurantii

*Sarcobatus*	Amaranthaceae
*Sarcobatus rubra* (?) (error for Salicornia rubra?)	[Brachyunguis tetrapteralis]
*S. vermiculatus*	Protaphis unaweepiensis; Brachyunguis bishopi, bonnevillensis

Key to apterae on Sarcobatus:-

1	ANT PT/BASE 1.2-1.6. R IV+V 1.5-1.8 × HT II. SIPH 1.8-2.0 × cauda which is triangular, about as long as its basal width	…..Protaphis unaweepiensis
–	ANT PT/BASE 0.7-1.0. R IV+V 0.8-1.1 × HT II. SIPH 0.4-1.25 × cauda, which is tongue-shaped, longer than its basal width	…..2
2	Longest hairs on ANT III 22-47 μm, and on ABD TERG 8, 41-60 μm. SIPH 0.7-1.25 × cauda. ABD TERG 2-5 as well as 1 and 7 often with marginal tubercles (MTu)	…..Brachyunguis bishopi
–	Longest hairs on ANT III 8-14 μm, and on ABD TERG 8, 14-27 μm. SIPH 0.4-0.8 × cauda. MTu only on ABD TERG 1 and 7	…..Brachyunguis bonnevillensis

*Sarcocephalus* see Nauclea	Rubiaceae
*Sarcocephalus bartlingii* see Nauclea orientalis

*Sarcochilus*	Orchidaceae
*Sarcochilus hartmannii*	Cerataphis orchidearum

*Sarcococca*	Buxaceae
*Sarcococca pruniformis*	[Jacksonia sp. (Banerjee et al. 1969 – 2 males)]
*S. ruscifolia*	Aulacorthum solani; Myzus persicae

Use key to polyphagous aphids.

Sarcopharyngia see Tabernaemontana

Apocynaceae

*Sarcopoterium*	Rosaceae
*Sarcopoterium spinosum*	Aphis gossypii, sanguisorbae

Use key to apterae on Sanguisorba.

*Sarcosperma*	Sapotaceae
*Sarcosperma laurinum*	Greenidea sp. 2 of Q. Liu et al. (2013)

*Sarcostemma*	Apocynaceae
*Sarcostemma clausum*	Aphis craccivora, gossypii, nerii

Use key to polyphagous aphids.

*Saribus*	Arecaceae
*Saribus rotundifolius*	Astegopteryx rhapidis

Sarothamnus see Cytisus

Fabaceae

*Sarracenia*	Sarraceniaceae
*Sarracenia purpurea*	Aulacorthum solani; Macrosiphum jeanae; [Myzocallis multisetis]; Neomyzus circumflexus

*Saruma*	Aristolochiaceae
*Saruma henryi*	Aulacorthum rhamni

*Sasa*	Poaceae
*Sasa albomarginata* = S. veitchii
*S. borealis*	Ceratovacuna cerbera, japonica; [Melanaphis koreana]; Takecallis arundicolens, arundinariae
*S. japonica* = Pseudosasa japonica
*S. kurilensis*	Takecallis arundicolens, arundinariae
*S. longiligulata*	Takecallis taiwana
*S. nipponica*	Takecallis arundicolens, sasae
*S. palmata*	Takecallis arundicolens, arundinariae, taiwana
*S. paniculata* = S. senanensis
*S. pygmaea*	Takecallis arundinariae
*S. ramosa*	Ceratovacuna japonica; Paracolopha morrisoni; Takecallis arundicolens
*S. senanensis*	[Ceratovacuna nekoashi]; Melanaphis bambusae; Paracolopha morrisoni; Takecallis arundicolens, sasae
*S. veitchii*	Ceratovacuna cerbera, [nekoashi]; Paracolopha morrisoni
*Sasa* sp(p).	Takecallis alba

Compared with the other large bamboo genera the aphid fauna of Sasa seems more limited, so a separate key is provided, but if no satisfactory answer is obtained then try the key to aphids on Arundinaria (or Bambusa). Yezaphis sasicola Matsumura cannot be keyed as no specimens are available (but see information from original description).

Key to species on Sasa:-

1	Antenna of aptera more than 0.5× BL, or if only alatae are present their antennae have circular or transversely oval secondary rhinaria	…..2
–	Antennae of aptera much less than 0.5× BL, and secondary rhinaria on the antennae of alatae are ring-like, extending more than half-way around the circumference of the antenna	…..7
2	Anal plate entire, cauda tongue-shaped, dark, similar in length to the thick short dark SIPH. ANT PT/BASE more than 2	…..Melanaphis bambusae
–	(All viviparae alate.) Anal plate bilobed, cauda knobbed. ANT PT/BASE 1.0 or less	…..3
3	Antennae shorter than (0.8-0.9 ×) body	…..4
–	Antennae longer than (1.3-1.7 ×) body	…..5
4	ABD TERG 8 with 6-8 hairs. ABD TERG 1-7 each with several pleural as well as spinal hairs	…..Takecallis sasae
–	ABD TERG 8 with 2-3(-4) hairs. ABD TERG 1-7 each with a pair of spinal hairs pleural hairs absent	…..Takecallis taiwana
5	Abdomen with a pair of elongate dark patches on each tergite. ANT III wholly dusky	…..Takecallis arundinariae
–	Abdomen without dark dorsal markings. ANT III with a black sensoriated section contrasting with pale base and apical half	…..6
6	ANT III with secondary rhinaria concentrated on a very short dark section. Cauda dusky	…..Takecallis alba
–	ANT III with secondary rhinaria spread over most of darkened proximal third. Cauda black	…..Takecallis arundicolens
7	Antennae of aptera extremely short, hardly longer than the elongate R V+V. Aptera without frontal horns. Tarsi 1-segmented. SIPH displaced towards the mid-line (on roots)	…..Paracolopha morrisoni
–	Antennae of aptera short, but much longer than the short R IV+V. Aptera (and immatures) with a pair of fromtal horns. Tarsi 2-segmented. SIPH in more normal position	…..8
8	Head of aptera with numerous long hairs. Dorsal body without any clearly demarcated wax pore plates	…..Ceratovacuna cerbera
–	Head of aptera sparsely hairy. Dorsal body with marginal groups of wax pore plates	…..Ceratovacuna japonica

*Sasamorpha* see Sasa	Poaceae
*Sasamorpha chiisanensis* = Sasa borealis
*S. gracilis* = Sasa borealis
*S. purpurascens* var. borealis = Sasa borealis

*Sassafras*	Lauraceae
*Sassafras albidum*	[Aphis fabae]; Euthoracaphis umbellulariae

*Satureja*	Lamiaceae
*Satureja acinos* = Clinopodium acinos
*S. calamintha* = Clinopodium ssp. glandulosum
*S. hortensis*	Aphis fabae
*S. montana*	Aphis origani, [serpylli]
*S. vulgaris* = Clinopodium vulgare

Use key to apterae under Clinopodium.

*Saurauia*	Actinidiaceae
*Saurauia napaulensis*	Aphis fabae; Myzus ornatus

*Sauropus*	Phyllanthaceae
*Sauropus albicans* = S. androgynus
*S. androgynus*	Aphis eugeniae; Schoutedenia ralumensis

Use key to apterae on Breynia.

*Saururus*	Saururaceae
*Saururus cernuus*	Rhopalosiphum nymphaeae
*S. loureiri*	Aphis fabae

Key to apterae on Saururus:-

–	Dorsal cuticle with a pattern of spinules arranged in polygons, with 1-3 spicules in the centre of each polygon. SIPH clavate	…..Rhopalosiphum nymphaeae
–	Dorsal cuticle without spinules arranged in polygons. SIPH not clavate	…..Aphis fabae

*Saussurea*	Asteraceae
*Saussurea affinis* = Hemistepta lyrata
*S. albescens*	Capitophorus formosartemisiae; Uroleucon budhium, kumaoni
S. alpina	Aulacorthum solani; [Uroleucon solidaginis]
*S. amara*	Aphis saussurearadicis; Uroleucon gobonis
*S. americana*	[Amphorophora sp. (see aphidtrek.org.]
*S. amurensis*	Capitophorus elaeagni
S. carthamoides = Hemistepta lyrata
*S. controversa*	[Uroleucon minor]
*S. elegans*	Macrosiphoniella victoriae
*S. grandifolia*	Aphis fabae; Uroleucon formosanum, fuchuense, saussureae
*S. japonica*	Uroleucon gobonis
*S. lappa*	Acyrthosiphon rubi; Brachycaudus helichrysi; Capitophorus formosartemisiae
*S. latifolia*	Aphis [cognatella of Ivanoskaya (1977) = euonymi?], fabae, [magnopilosa]
*S. lyrata* see Hemisteptia lyrata
*S. neoserrata*	Aphis [acanthoidis], fabae; Uroleucon saussureae, skurichinae
*S. nepalensis*	[Aphis longisetosus]
*S. nigrescens*	Chitinosiphon abdomenigrum
*S. odontolepis*	Aphis saussurearadicis
*S. parviflora*	Aphis fabae; [Macrosiphum chukotense]
*S. piptathera*	Dysaphis indica
*S. pseudo-tilesii*	Aphis fabae; Aulacorthum solani
*S. pulchella*	Aphis fabae, [sambuci], saussurearadicis; Capitophorus elaeagni; Gredinia pilosotuba; Macrosiphoniella lazoica; Uroleucon [cephalonopli], gobonis, skurichinae, ussuriense
*S. salicifolia*	Acyrthosiphon dauricum; Aphis fabae; Macrosiphoniella saussureae
*S. salsa*	[Macrosiphoniella sp. (Kadyrbekov & Aoitzhanova 2005b)]; [Titanosiphon chondrillae]
*S. ussuriensis*	Capitophorus elaeagni
*Saussurea* sp.	Acyrthosiphon saussureae; Macrotrichaphis rarissima

Key to apterae on Saussurea:-

1	SIPH with a distal zone of polygonal reticulation. ANT III with numerous rhinaria usually extending into distal half	…..2
–	SIPH without any distinct zone of polygonal reticulation (sometimes with 1-3 rows of interconnected striae). ANT III without rhinaria or with a few near base	…..15
2	SIPH almost always with hairs (examine several specimens)	…..3
–	SIPH without hairs	…..5
3	Thoracic spiracular apertures much larger than abdominal ones. Cauda with more than 30 hairs	…..Gredinia pilosotuba
–	Thoracic spiracular apertures similar in size to abdominal ones. Cauda with 10-28 hairs	…..4
4	SIPH with c.4-5 hairs, c.3 × longer than cauda, which bears 10-13 hairs. First tarsal segments with 5 hairs	…..Macrotrichaphis rarissima
–	SIPH with (0-) 5-21 hairs, 1.6-2.5 × longer than cauda which bears 20-28 hairs. First tarsal segments with 3 hairs	…..Macrosiphoniella lazoica
5	SIPH only 0.10-0.14 × BL, reticulated on distal 0.5-0.7 of length. Cauda triangular, pointed, only about as long as its basal width. ANT tubercles very low	…..Macrosiphoniella saussureae
–	SIPH more than 0.14 × BL, reticulated on less than distal 0.5. Cauda tongue- or finger-shaped, longer than its basal width. ANT tubercles well developed	…..6
6	SIPH 1.0-1.1 × cauda, with reticulation on distal 0.34-0.38. R IV+V 0.8-0.9 × HT II	…..Macrosiphoniella victoriae
–	SIPH 1.2-2.2 × cauda, with reticulation on distal 0.12-0.36. R IV+V 1.0-2.0 × HT II	…..7
7	ANT III very long, 1.5-2.1 × ANT IV+V together, and bearing very numerous (96-135) strongly protruberant secondary rhinaria	…..Uroleucon formosanum
–	ANT III shorter than or about equal in length to ANT IV+V together, with 18-56 rhinaria	…..8
8	SIPH 2.0-2.2 × cauda, with reticulation on distal 0.12-0.17 of length. R IV+V very long and thin, 1.8-2.0 × HT II	…..Uroleucon budhium
–	SIPH 1.1-1.9 (-2.0) × cauda, with reticulation on distal 0.19-0.36 of length. R IV+V 1.0-1.85 × HT II	…..9
9	Crescent-shaped ante-siphuncular sclerites present	…..10
–	Ante-siphuncular sclerites absent	…..12
10	R IV+V 1.0-1.1 × HT II	…..Uroleucon skurichinae
–	R IV+V 1.5-1.85 × HT II	…..11
11	SIPH 0.25-0.30 × BL, with reticulation on distal 0.24-0.27 of length. Cauda long and finger-like, 2.6-3.1 × its basal width. R IV+V 1.7-1.85 × HT II	…..Uroleucon saussureae
–	SIPH c. 0.14 × BL, with reticulation on distal 0.28-0.36 of length. Cauda elongate triangular, pointed at apex, 1.7-2.0 × its basal width. R IV+V 1.5-1.7 × HT II	…..Uroleucon ussuriense
12	SIPH 1.1-1.3 × the long, pale cauda, which bears 25-35 hairs. Hind tibia with a row of short peg-like hairs	…..Uroleucon fuchuense
–	SIPH 1.5-2.0 × the pale, dusky or dark cauda, which bears either 12-20 hairs or more than 40. Hind tibia without peg-like hairs	…..13
13	Cauda paler than SIPH, with apical hairs distinctly shorter than more proximal ones	…..Uroleucon kumaoni
–	Cauda as dark as SIPH, with hairs all similarly long	…..14
14	Cauda with more than 40 hairs. R IV+V 1.65-1.8 × HT II. Tibiae black	…..Uroleucon giganteum
–	Cauda with 13-20 hairs. R IV+V 1.1-1.3 × HT II. Tibiae pale in middle	…..Uroleucon gobonis (or compositae?)
15	Dorsal body hairs long, thick and capitate, arising from tuberculate bases	…..16
–	Dorsal body hairs short, or if long then pointed and not arising from tuberculate bases	…..17
16	ANT III with 2-4 thick, capitate hairs about as long as middle diameter of segment. Dorsal abdominal hairs duplicated or triplicated, so that there are 12-16 long thick capitate hairs per segment	…..Capitophorus formosartemisiae
–	ANT III with all hairs very short. Dorsal abdominal hairs not duplicated, so that there are 6 per segment	…..Capitophorus elaeagni
17	ANT tubercles moderately to well developed, their inner faces divergent. ANT III with a few rhinaria on basal part	…..18
–	ANT tubercles absent or weakly developed. ANT III without rhinaria	…..21
18	Tergum with an extensive dark sclerotic shield. Head dark and densely spiculose. Cauda short, less than 2 × its basal width, with 4 hairs	…..Chitinosiphon abdomenigrum
–	Tergum pale. Head pale, not densely spiculose. Cauda finger-like, at least 2 × its basal width, with 6-10 hairs	…..19
19	ANT longer than BL, with ANT PT/BASE 6.5-7.0. SIPH more than 2 × cauda	…..Acyrthosiphon rubi
–	ANT as short as or shorter than BL, with ANT PT/BASE 2.0-4.2	…..20
20	ANT PT/BASE 3.5-4.2. SIPH less than 2 × cauda	…..Acyrthosiphon dauricum
–	ANT PT/BASE 2.0-2.3. SIPH 2.5-2.6 × cauda	…..Acyrthosiphon saussureae
21	Cauda helmet-shaped, not more than 1.1 × longer than its basal width in dorsal view, and bearing 4-6 hairs. ABD TERG 7 without marginal tubercles (MTu). R IV+V with 4-6 accessory hairs	…..22
–	Cauda tongue-shaped, more than 1.2 × its basal width in dorsal view, and bearing 5-24 hairs. ABD TERG 7 (and 1) always with MTu. R IV+V with 2 accessory hairs	…..23
22	SIPH dark, cylindrical, with slight distal swelling, 2.0-2.2 × cauda. MTu often present on ABD TERG 1-5. Spiracular apertures reniform	…..Dysaphis indica
–	SIPH pale, conical, 0.8-1.3(-2.0) × cauda. MTu absent. Spiracular apertures large and rounded	…..Brachycaudus helichrysi
23	R IV+V 1.3-1.5 × HT II. MTu usually present on ABD TERG 1-4 and 7	…..Aphis saussuraeradicis
–	R IV+V 0.9-1.1 (-1.4) × HT II. MTu only sporadically present on ABD TERG 2-4	…..go to key to polyphagous aphids, starting at couplet 24

*Savia*	Phyllanthaceae
*Savia sessiliflora*	Aphis (Toxoptera) aurantii

*Savignya*	Brassicaceae
*Savignya parviflora*	Myzus persicae

*Saviniona*	Malvaceae
*Saviniona acerifolia*	Aphis gossypii; Macrosiphum euphorbiae; Myzus persicae

*Saxifraga*	Saxifragaceae
*Saxifraga aizoides*	Aphis fabae, triglochinis; Brachycaudus helichrysi; Cavariella [aquatica], saxifragae
*S. aizoon* = S.paniculata
*S. alpigena* see S. stellaris
*S. aquatica*	Rhopalosiphum nymphaeae
*S. callosa* see S. lingulata
*S. canaliculata*	Aphis fabae
*S. careyana* = Micranthes caryana
*S. cespitosa* see S. groenlandica
*S. cochlearis*	Macrosiphum euphorbiae
*S. cuneifolia*	[Sitobion avenae]
*S. cymbalaria*	Macrosiphum euphorbiae
*S. decipiens* (?)	Myzus ascalonicus
*S. fusca* (incl. ssp. kikubuki)	Taiwanomyzus montanus
*S. granulata*	Aphis craccivora; Nasonovia dasyphylli
*S. groenlandica* (= S. cespitosa)	Nasonovia vannesii
*S. hirsuta*	Aphis fabae
*S. hypnoides*	Nasonovia dasyphylli
*S. lingulata* (= S. callosa)	Aphis fabae; Nasonovia dasyphylli
*S. michauxii* = Spatularia michauxii
*S. nelsoniana*	[Macrosiphum chukotense]
*S. nivalis*	Nasonovia saxifragae
*S. oppositifolia* (incl. var. splendens)	Macrosiphum euphorbiae (as gei); Myzus persicae; Nasonovia brevipes, saxifragae
*S. paniculata*	Aulacorthum solani; Nasonovia dasyphylli, saxifragae
*S. punctata*	Myzus asamensis
*S. rosacea*	Macrosiphum euphorbiae
*S. rotundifolia*	Nasonovia dasyphylli, ribisnigri
*S. sarmentosa* = S. stolonifera
*S. × somedana*	Nasonovia saxifragae
*S. splendens* see S. oppositifolia
*S. stellaris* (incl. alpigena)	Nasonovia dasyphylli
S. stolonifera	Aphis spiraecola; Macrosiphum euphorbiae; Neomyzus circumflexus
*S. tricuspidata*	Nasonovia vockerothi
*S. umbrosa*	Aphis sambuci
*Saxifraga* spp.	[Macrosiphum constrictum]; Myzus ornatus; [Nasonovia acyrthosiphon]

Key to apterae on Saxifraga (and Spatularia):-

1	ABD TERG 8 with a backwardly-directed process similar in length to and almost covering cauda. ANT PT/BASE 0.9-1.0. Tergum strongly sclerotised, often dark. SIPH swollen distally	…..Cavariella saxifragae
–	No supracaudal process, ANT PT/BASE more than 1.5 and other characters not in that combination	…..2
2	Head spiculose. SIPH black, somewhat clavate, more than 2.7 × cauda which is also black and bears 4-5 hairs. Dorsum with extensive black sclerotisation	…..Taiwanomyzus montanus
–	Without that combination of characters	…..3
3	Thoracic spiracular apertures much larger than abdominal ones . ANT III usually with more than 10 sec. rhin., and often some also on IV, or IV and V	…..4
–	Thoracic spiracular apertures similar in size to abdominal ones. ANT III with or without a few (1-10) rhinaria on basal part, none on IV or V	…..11
4	Cauda usually with 7 hairs, rarely 6, 8 or 9. ANT PT/BASE 7.0-11.4 (usually more than 8.4). SIPH without imbrication. Dorsal abdomen with paired intersegmental markings	…..Nasonovia ribisnigri
–	Cauda usually with 5 hairs. ANT PT/BASE 2.5-8.4. SIPH usually with imbrication. Dorsum pale or with more extensive dark sclerotisation	…..5
5	Dorsal abdomen with extensive dark sclerotisation, fused between tergites to form a large dark patch	…..6
–	Dorsal abdomen pale or with dark cross-bars, not fused between tergites	…..7
6	ANT PT/BASE (3.6-) 5.0-8.8. SIPH 1.4-2.5 × cauda. Sec. rhin. distributed ANT III 10-42, IV 0-21, V 0-4	…..Nasonovia dasyphylli
–	ANT PT/BASE 2.5-4.7 (-5.4). SIPH 1.2-1.6 × cauda. Sec. rhin. distributed ANT III 4-25, IV 0-2, V 0	…..Nasonovia saxifragae (dark form)
7	ANT PT/BASE (4.8-) 5.7-8.2. Longest hairs on ANT III often longer than (0.7-1.3) × BD III	…..8
–	ANT PT/BASE 2.5-4.2 (-5.0). Longest hairs on ANT III 0.5-1.0 × BD III	…..9
8	Abdomen usually with short dusky/dark spinal cross bars on ABD TERG 1-6, and separate sclerites at bases of pleural and marginal hairs. R IV+V 1.6-2.2 × HT II. SIPH with spinules on imbrications	…..Nasonovia carolinensis
–	Abdomen without dark sclerites on ABD TERG 1-6. R IV+V 1.4-1.5 × HT II. SIPH without spinules on imbrications	…..Nasonovia vannesii
9	R IV+V c.2 × HT II, with c.10 accessory hairs	…..Nasonovia brevipes
–	R IV+V 1.2-1.8 × HT II, with 12-16 accessory hairs	…..10
10	SIPH 0.11-0.12 × BL, 0.9-1.3 × cauda, and 3.5-4 × diameter at midlength	…..Nasonovia vockerothi
–	SIPH 0.16-0.24 × BL, 1.4-1.8 × cauda, and more than 5 × diameter at midlength	…..Nasonovia saxifragae (pale form)
11	Dorsal cuticle with bead-like spinules arranged in polygons, each polygon enclosing 1-4 separate spinules. SIPH dusky-dark, clavate	…..Rhopalosiphum nymphaeae
–	Dorsal cuticle without spinules arranged in polygons. SIPH pale or dark, clavate, cylindrical or tapering	…..12
12	Marginal abdominal tubercles (MTu) present on at least ABD TERG 1-4 and 7. SIPH and Cauda dark. SIPH 1.7-3.5 × cauda which is short and rounded and bears 10-20 hairs	…..Aphis sambuci
–	MTu absent or only regularly present on ABD TERG 1 and 7, and other characters not in above combination	…..13
13	ANT PT/BASE 1.1-1.8. MTu on ABD TERG 1 and 7. SIPH rather pale, tapering, 0.7-1.3 × cauda. (Al. with sec. rhin. distributed ANT III 25-60, IV 9-25, V 7-17)	…..Aphis triglochinis
–	ANT PT/BASE 1.8-6.2, and other characters not in that combination	…..14
14	Head densely spiculose. SIPH dark, coarsely imbricated, cylindrical or slightly swollen on distal half, distinctly constricted at apex, with a large flange. R IV+V 1.5-1.7 × HT II	…..Myzus asamensis
–	Without that combination of characters	…..go to key to polyphagous aphids

*Scabiosa*	Dipsacaceae
Scabiosa africana	Macrosiphum rosae
*S. argentea*	Aphis confusa, spiraecola, thomasi
*S. arvensis* = Knautia arvensis
*S. atropurpurea*	Aphis confusa, fabae, thomasi; Macrosiphum rosae, weberi
*S. austroaltaica*	Aphis confusa
*S. banatica*	Aphis confusa
*S. canescens*	Aphis confusa, thomasi
*S. caucasica*	Aulacorthum solani; Macrosiphum rosae; Myzus persicae
*S. columbaria*	Aphis confusa, thomasi; Macrosiphum euphorbiae, rosae, weberi; Ovatomyzus [boraginacearum], chamaedrys
*S. comosa* (incl. var. lachnophylla)	Aphis confusa, spiraecola, thomasi
*S. isetensis*	Aphis thomasi
S. lachnophylla = S. comosa var. lachnophylla
S. maritima = S. atropurpurea
*S. ochroleuca*	Aphis confusa, thomasi; Macrosiphum rosae
*S. officinalis* (?)	Macrosiphum rosae
*S. songarica*	Dysaphis cephalariae
S. sosnowskii	Aphis confusa
S. stellata	Macrosiphum rosae
*S. succisa* see Succisa pratensis
*S. triandra*	Aphis thomasi
*S. ucranica*	Aphis confusa, thomasi
*Scabiosa* sp.	Aphis gossypii

Key to apterae on Scabiosa:-

1	ANT tubercles undeveloped or weakly developed. ABD TERG 1 and 7 (at least) with marginal tubercles (MTu). Cauda pale or dark	…..2
–	ANT tubercles well developed. ABD TERG 7 without MTu. Cauda pale	…..6
2	Cauda helmet-shaped or bluntly triangular, shorter than its basal width in dorsal view. Head and all thoracic and abdominal segments with spinal tubercles (STu), and MTu present on ABD TERG 1-7	…..Dysaphis cephalaria
–	Cauda tongue-shaped, much longer than its basal width. STu absent, and MTu only regularly present on ABD TERG 1 and 7	…..3
3	Femoral hairs all shorter than diameter of trochantro-femoral suture. Cauda pale, dusky or dark with 4-9 hairs	…..4
–	Many femoral hairs long and fine-pointed, exceeding diameter of trochantro-femoral suture. Cauda black and bearing 7-24 hairs	…..5
4	Posterior hair on hind trochanter 0.2-0.5 × diameter of trochantro-femoral suture. Hairs on anterior half of subgenital plate 0.2-0.6 × ANT BD III	…..Aphis thomasi
–	Posterior hair on hind trochanter 0.6-1.1 × diameter of trochantro-femoral suture. Hairs on anterior half of subgenital plate 1.2-2.0 × ANT BD III	…..Aphis confusa (or Aphis gossypii – see text)
5	ANT III 0.9-1.2 × cauda, which usually has a distinct midlength constriction and bears 6-15 (usually 9-11) hairs. Dorsal abdomen without any dark markings	…..Aphis spiraecola
–	ANT III 1.2-1.9 × cauda which is usually without any constriction and bears 11-24 hairs. Dorsal abdomen usually with scattered dark markings anterior to SIPH and dark cross-bands on ABD TERG 7 and 8	…..Aphis fabae
6	Head without spicules	…..7
–	Head spiculose	…..10
7	Head pale. SIPH pale, slightly swollen distally, without subapical polygonal reticulation. ANT III without rhinaria	…..Ovatomyzus chamaedrys
–	Head pale or dark. SIPH pale or dark with a subapical zone of polygonal reticulation. ANT III with 1-35 rhinaria	…..8
8	Head, legs and SIPH mainly pale. ANT III with 1-10 rhinaria	…..Macrosiphum euphorbiae
–	Head, legs and SIPH mainly dark. ANT III with 5-35 rhinaria	…..9
9	Body spindle-shaped. SIPH thicker than hind tibiae at their respective midlengths, and 1.8-2.2 × head width across (and including) eyes	…..Macrosiphum rosae
–	Body oval. SIPH about equal in thickness to hind tibiae at midlength, and 1.1-1.5 × head width across eyes	…..Macrosiphum weberi
10	SIPH slightly clavate. ANT 0.7-1.0 × BL, without rhinaria on ANT III	…..Myzus persicae
–	SIPH tapering/cylindrical. ANT 1.1-1.3 × BL, with (0-)1-2 (-4) rhinaria near base of ANT III	…..Aulacorthum solani

*Scaevola*	Goodeniaceae
*Scaevola frutescens*	Aphis gossypii
*S. koenigii* = S. taccada
*S. sericea* = S. taccada
*S. taccada*	Aphis gossypii
Scaevola sp.	Myzus persicae

Use key to polyphagous aphids.

*Scaligeria*	Apiaceae
Scaligera bucharica = Elaeosticta bucharica

*Scandix*	Apiaceae
*Scandix pecten-veneris*	Aphis craccivora, fabae, solanella; Cavariella aegopodii; Myzus persicae; Semiaphis dauci

Use key to apterae on Daucus.

Schanginia see Sueada

Amaranthaceae

*Schefflera* (including Didymopanax, Heptapleurum, Tupidanthus)	Araliaceae
*S. actinophylla*	Aphis gossypii, hederae, spiraecola
*S. arborea*
*S. arboricola*	Aphis aurantii, gossypii, hederae, spiraecola
*S. avenis*	Aphis (Toxoptera) aurantii; Macrosiphum euphorbiae
*S. calyptrata* = S. avenis
*S. heptaphylla*	Aphis aurantii, odinae; Cavariella araliae; Neomyzus circumflexus
*S. lutchuensis* (?)	Aphis (Toxoptera) aurantii; Cavariella araliae
*S. morototoni*	Aphis (Toxoptera) aurantii
*S. octophylla* = S. heptaphylla
*S. pubigera*	Aphis gossypii
*S. stelzneriana* = S. pubigera
*S. umbellifera*	Macrosiphum euphorbiae
*S. veitchii*	Myzus persicae
*S. venulosa*	Aphis gossypii; Myzus persicae
*Schefflera* sp.	Brachycaudus helichrysi

Key to aphids on Schefflera:-

1	ABD TERG 8 with a long backwardly-directed process, broad at base but with a narrow apex that extends beyond cauda	…..Cavariella araliae
–	No supracaudal process	…..2
2	SIPH and cauda both black. R IV+V 1.3-1.6 × HT II. Apterae often alatiform, with 0-19 rhinaria on ANT III. Marginal tubercles (MTu) frequently present on ABD TERG 2-4, as well as 1 and 7	…..Aphis hederae
–	Without that combination of characters	…..go to key to polyphagous aphids

*Scheuchzeria*	Scheuchzeriaceae
*Scheuchzeria palustris*	Aphis triglochinis; [Macrosiphum nasonovi of Zirnits1930]

*Schima*	Theaceae
*Schima noronhae*	Guger Tree
	Greenidea schimae
S. superba	Greenidea schimae
*S. wallichii*	Aphis aurantii, citricidus, fabae, gossypii, nasturtii, odinae, spiraecola; Brachycaudus helichrysi; Eutrichosiphum pasaniae, [pseudopasaniae]; Greenidea [longicornis], longirostris, schimae; Myzus ornatus, persicae; Neomyzus circumflexum; [Subovatomyzus leucosceptri]

Key to aphids on Schima:-

1	SIPH without hairs	…..go to key to polyphagous aphids
–	SIPH with numerous long hairs	…..2
2	SIPH black, without any pale reticulation, 0.25-0.32 × BL. Cauda without a median papilla	…..Eutrichosiphum pasaniae
–	SIPH pale brown, with pale reticulation over entire length except spinulose apical part, 0.42-0.56 × BL. Cauda with a median papilla	…..3
3	Aptera with R IV+V 0.23-0.27 mm long, 1.7-2.3 × HT II, with 10-12 accessory hairs. Alata with 16-26 rhinaria on ANT III	…..Greenidea schimae
–	Apterae with R IV+V 0.26-0.33 mm long, 2.0-2.75 × HT II, with 12-18 accessory hairs. Alata with 19-33 rhinaria on ANT III	…..Greenidea longirostris

*Schimpera*	Brassicaceae
*Schimpera arabica*	Aphis craccivora; Myzus persicae

Use key to polyphagous aphids.

*Schinus* Peppertrees	Anacardiaceae
*Schinus dependens*	Aphis schinifoliae
S. gracilipes	Aphis schinifoliae
*S. johnstonii*	Aphis schinivora
*S. molle*	Aphis craccivora, gossypii, schinifoliae; Myzus persicae
S. polygamus	Aphis schinifoliae
S. roigii	Aphis schinifoliae
*S. terebinthifolius*	Aphis aurantii, gossypii, odinae; [Greenidea psidii]; [Sitobion congolense]

Key to species on Schinus:-

1	SIPH entirely pale. ANT tubercles undeveloped. Well-developed marginal tubercles (MTu) usually present on ABD TERG 2-6 as well as 1 and 7	…..Aphis schinifoliae
–	If SIPH are pale then other characters do not apply	…..2
2	SIPH dark, shorter than R IV+V and only 0.3-0.7 × cauda, which is also dark and bears 4-8 hairs. ANT tubercles undeveloped. ABD TERG 1 and 7 and often also ABD TERG 2-6 with well-developed, rather flat MTu	…..Aphis schinivora
–	Without that combination of characters	…..go to key to polyphagous aphids

*Schisandra*	Schisandraceae
Schisandra grandiflora	Rhopalosiphoninus ehretis

*Schismus*	Poaceae
*Schismus arabicus*	Aphis fabae

*Schizachyrium*	Poaceae
*Schizachyrium scoparium*	Anoecia cornicola

*Schizachne*	Poaceae
*Schizachne purpurascens*	Sitobion avenae

*Schizanthus*	Solanaceae
*Schizanthus* sp.	Neomyzus circumflexus

*Schizonepeta* see Nepeta	Lamiaceae
*Schizonepeta multifida* = Nepeta multifida

*Schizopepon*	Cucurbitaceae
*Schizopepon bryoniifolius*	Aulacorthum magnoliae

*Schizophragma*	Hydrangeaceae
*Schizophragma hydrangeoides*	Taiwanomyzus montanus

*Schizostachyum*	Poaceae
*Schizostachyum blumei*	Astegopteryx singaporensis; Ceratoglyphina bambusae; Pseudoregma pendleburyi
*S. brachycladum*	Astegopteryx singaporensis; Ceratoglyphina bambusae; Glyphinaphis bambusae
*S. lima*	Ceratovacuna hoffmani
*S. zollingeri*	Ceratoglyphina bambusae; Pseudoregma sp. (Stern et al. 1997)

Use key to aphids on Bambusa.

*Schizostylis* see Hesperantha	Iridaceae
*Schizostylis coccinea* = Hesperantha coccinea

*Schkuhria*	Asteraceae
*Schkuhria anthemoides*	Ucrimyzus villalobosi
S. pinnata	Uroleucon compositae
*S. virgata*	Ucrimyzus villalobosi

Couplet to separate these two species:-

–	SIPH cylindrical or tapering, entirely dark, with a distal zone of polygonal reticulation. Cauda similarly dark	…..Uroleucon compositae
–	SIPH swollen on about distal 0.7, pale at least at base, without distal polygonal reticulation. Cauda pale	…..Ucrimyzus villalobosi

Schlumbergera see Zygocactus

Cactaceae

*Schoenefeldia*	Poaceae
*Schoenefeldia gracilis*	Hysteroneura setariae

*Schoenoplectus* (including Bolboschoenus)	Cyperaceae
*Schoenoplectus americanus*	Thripsaphis ballii
*S. californicus*	Rhopalosiphum rufiabdominale
*S. lacustris*	Hyalopterus pruni; Rhopalosiphum nymphaeae, [parvae]; Schizaphis minuta, scirpi; Sitobion avenae, fragariae; Subsaltusaphis picta
*S. maritimus*	Sipha glyceriae
*S. tabernaemontani*	Rhopalosiphum cerasifoliae, nymphaeae
*S. triqueter*	Schizaphis scirpi

Use key to apterae on Scirpus.

*Schoenus*	Cyperaceae
*Schoenus nigricans*	[Anoecia corni]; Rhopalosiphum padi; Sipha glyceriae; Vesiculaphis theobaldi

Use key to apterae on Scirpus.

*Scholtzia*	Myrtaceae
*Scholtzia involucrata* = S. obovata
*S. obovata*	Aphis gossypii

*Schomburgkia*	Orchidaceae
*Schomburgkia* sp.	Cerataphis orchidearum

*Schotia*	Fabaceae
*Schotia brachypetala*	Aphis (Toxoptera) aurantii; Myzus persicae
*S. latifolia*	Aphis (Toxoptera) aurantii

Use key to polyphagous aphids.

*Schoutenia*	Tiliaceae
*Schoutenia ovata* (= Actinophora fragrans)	Cervaphis echinata, schouteniae

Couplet to separate these species:-

–	Frontal branched processes including the apical hair more than 0.4 mm long, 0.8-1.0 × length of antennae	…..Cervaphis echinata
–	Frontal branched processes including the apical hair less than 0.4 mm long, 0.4-0.6 × length of antennae	…..Cervaphis schouteniae

*Schouwia*	Brassicaceae
*Schouwia purpurea*	Aphis gossypii
*S. thebaica* = S. purpurea

*Schrenkia*	Apiaceae
*Schrenkia golickeana* (?)	Brachyunguis flexosiphon
*Schrenkia ugamica* (?)	Hyadaphis coerulescens, [coriandri]
*Schrenkia vaginata*	Aphis craccivora; Semiaphis dauci

Key to apterae on Schrenkia:-

1	ANT PT/BASE less than 1.0	…..Brachyunguis flexosiphon
–	ANT PT/BASE more than 1.5	…..2
2	SIPH very small and flangeless, only about 0.5 × cauda or less, with their apertures slanted towards mid-line	…..Semiaphis dauci
–	SIPH longer than cauda	…..3
3	Dorsal abdomen unsclerotised. SIPH clavate	…..Hyadaphis coerulescens
–	Dorsal abdomen with extensive dark sclerotisation. SIPH tapering	…..Aphis craccivora

(or go to key to polyphagous aphids)

*Sciadopitys*	Taxodiaceae
*Sciadopitys verticillata*	Eulachnus thunbergii

*Scilla* (including Oziroe)	Asparagaceae
*Scilla biflora*	Myzus persicae
*S. madeirensis*	Myzus hemerocallis
Scilla sp.	Dysaphis tulipae

Key to apterae on Scilla:-

1	SIPH dark. Cauda helmet-shaped, not longer than its basal width in dorsal view. Spinal tubercles (STu) present on head and ABD TERG 8, or 7 and 8	…..Dysaphis tulipae
–	SIPH pale. Cauda tongue-shaped, much longer than its basal width. STu absent from head, and rarely on ABD TERG 8	…..2
2	SIPH tapering or cylindrical on distal half, more than 2.5 × cauda, with coarse imbrication. (Al. without a black dorsal abdominal patch)	…..Myzus hemerocallis
–	SIPH slightly swollen on distal half, less than 2.5 × cauda, with normal imbrication. (Al. with a black dorsal abdominal patch)	…..Myzus persicae

*Scindapsus*	Araceae
*Scindapsus* sp.	Rhopalosiphum nymphaeae

*Scirpoides*	Cyperaceae
*Scirpoides holoschoenus*	Colopha hispanica; Schizaphis scirpi; Sitobion avenae
Use key to apterae on Scirpus.

Scirpus

Cyperaceae

Many species have been transferred from Scirpus to other genera. We have left some of these in the Scirpus list, with the new generic name in brackets.

*Scirpus americanus* = Schoenoplectus americanus
*S. atrocinctus*	Schizaphis scirpicola
*S. australis* = Scirpoides holoschoenus
*S. caespitosus* = Trichophorum caespitosum
*S. californicus* = Schoenoplectus californicus
*S. campestris* (?)	Rhopalosiphum musae
*S. cernuus* (= Isolepis cernua)	Schizaphis scirpi
*S. grossus* (= Actinoscirpus grossus)	Carolinaiascirpi
*S. holoschoenus* = Scirpoides holoschoenus
*S. lacustris* = Schoenoplectus lacustris
*S. maritimus* (= Bolboschoenus maritimus)	[Caricosipha paniculatae]; [Juncobia leegei]; Rhopalosiphum maidis, padi; Schizaphis scirpi; Sipha glyceriae; Sitobion avenae; Subsaltusaphis picta; Vesiculaphis theobaldi
*S. microcarpus*	Ceruraphis eriophori, viburnicola (in greenhouse)
*S. palustris* = Eleocharis palustris
*S. rubrotinctus* = Scirpus microcarpus
*S. speciosus* = Eriophorum angustifolium
*S. sylvaticus*	Ceruraphis eriophori; Rhopalosiphum nymphaeae, padi; Saltusaphis scirpus; Schizaphis scirpi; Sitobion avenae; Subsaltusaphis ornata
*S. tabernaemontani* = Schoenoplectus tabernaemontani
*S. triqueter* = Schoenoplectus triqueter
*S. validus* = Schoenoplectus tabernaemontani
*S. vulgaris* (= Bolboschoenus maritimus)	Sitobion avenae
*Scirpus* spp.	Atheroides hirtellus; Metopolophium dirhodum; Schizaphis brachytarsus, caricis; [Subsaltusaphis virginica]

Key to apterae on Scirpus (also Bomboschoenus, Schoenoplectus and Scirpoides):-

1	SIPH tubular; tapering, cylindrical or swollen, clearly longer than their basal widths	…..2
–	SIPH in form of short truncate cones not clearly longer than their basal widths, or present merely as pores, or completely absent	…..21
2	SIPH very small, thin and flangeless, less than 0.7 × cauda	…..Hyalopterus pruni
–	SIPH not thin, more than 0.8 × cauda, with a distinct apical flange	…..3
3	Front of head between ANT produced into 3 large separate rounded processes, each bearing spine-like hairs. SIPH scabrous, cylindrical for most of length and abruptly narrowed distally, with a small terminal aperture. ANT PT/BASE 1.37-1.8	…..Vesiculaphis theobaldi
–	Front of head not produced into 3 large rounded processes bearing spine-like hairs. SIPH various, but not very small at apex. ANT PT/BASE more than 1.8	…..4
4	Tergum almost entirely dark, and SIPH jet black	…..5
–	Tergum usually pale, sometimes with dusky/dark central patch or dark markings. SIPH pale or dark	…..6
5	SIPH short, less than 0.1 × BL, with close-set rows of fine spinules	…..Ceruraphis viburnicola
–	SIPH more than 0.2 × BL, with coarse denticulate imbrication	…..Ceruraphis eriophori
6	ANT tubercles moderately to well developed, projecting beyond middle part of head in dorsal view, smooth and divergent or bearing rounded scabrous or spiculose processes. ANT III with 1-4 small rhinaria near base	…..7
–	ANT tubercles weakly developed, not projecting beyond middle of head in dorsal view. ANT III without rhinara	…..10
7	Head with inner sides of ANT tubercles developed as rounded, scabrous or spiculose processes. R IV+V 1.2-1.3 × HT II	…..Carolinaia scirpi
–	Head with inner sides of ANT tubercles smooth and divergent. R IV+V 0.60-0.85 × HT II	…..8
8	SIPH pale, without subapical polygonal reticulation	…..Metopolophium dirhodum
–	SIPH dark, with a subapical zone of polygonal reticulation	…..9
9	SIPH 1.75-2.25 × cauda, which has a rounded apex	…..Sitobion fragariae
–	SIPH 1.0-1.5 × cauda, which has a more pointed apex	…..Sitobion avenae
10	ANT 5-segmented, bearing long hairs up to 4-5 × BD III. ANT PT/BASE 4.5-5.9, with PT usually curved	…..Rhopalosiphum rufiabdominale
–	ANT 5- or 6-segmented, but if 5-segmented then hairs are shorter and/or ANT PT/BASE is less than 3.6	…..11
11	ABD TERG 8 with 5-13 hairs. Hind tibia with numerous long, fine hairs, exceeding 2 × its diameter at midlength, along whole length. Longest hairs on ANT III longer than BD III. Papilliform marginal tubercles usually present on all or most of ABD TERG 1-7	…..12
–	ABD TERG 8 with 2-4 hairs. Hind tibia with shorter hairs, or if with hairs about 2 × its middle diameter then these do not extend to basal part. Longest hairs on ANT III rarely exceeding BD III. Marginal tubercles present or absent from ABD TERG 2-6	…..15
12	ANT III with 15-16 hairs. SIPH 2.57-2.83 × cauda	…..Schizaphis brachytarsus
–	ANT III with 6-13 hairs. SIPH 1.50-2.78 × cauda	…..13
13	Subgenital plate usually with 2-4 hairs on anterior half (rarely up to 10). Dorsal body and ANT hairs variable in length; often some of those on both ANT III and ABD TERG 3 have blunt apices and are less than 50 μm long (range 28-87 μm and 29-100 μm respectively). R IV+V 1.02-1.25 (-1.38) × HT II. (Al. with (0-)2-5 rhinaria on ANT V)	…..Schizaphis caricis
–	Subgenital plate with (3-)5-14 hairs on anterior half. Dorsal body hairs all more than 65 μm long with pointed apices; hairs on ANT III and ABD TERG 3 are in range (30-) 50-108 μm and 81-132 μm respectively. R IV+V either 0.89-1.14 or 1.25-1.43 × HT II. Al with 0-1 rhinaria on ANT V	…..14
14	R IV+V 0.89-1.14 × HT II. Hairs on ANT III 53-108 μm long	…..Schizaphis scirpi
–	R IV+V 1.25-1.43 × HT II. hairs on ANT III (30-) 50-83 μm long	…..Schizaphis scirpicola
15	SIPH distinctly clavate, 1.8-2.4 × cauda	…..Rhopalosiphum nymphaeae
–	SIPH not clavate, 1.2-c.2.0 × cauda	…..16
16	ANT with primary rhinaria on ANT V much smaller than that on VI, its diameter 0.3-0.4 × width of segment at that point. SIPH pale with dark apices	…..Schizaphis minuta
–	ANT with primary rhinarium on ANT V about the same size as that on VI, its diameter more than 0.5 of width of segment at that point. SIPH pale or dark	…..17
17	ANT PT/BASE 1.7-2.8. R IV+V 0.8-0.9 × HT II. Body rather elongate oval	…..Rhopalosiphum maidis
–	ANT PT/BASE 2.8-5.2. R IV+V 0.9-1.5 × HT II. Body rather broadly oval	…..18
18	ANT usually 5-segmented, with longest hairs on ANT III 1-2 × BD III. SIPH c.2 × cauda	…..Rhopalosiphum oxyacanthae
–	ANT 6-segmented, with longest hiars on ANT III 0.4-1.0 × BD III. SIPH 1.2-1.9 × cauda	…..19
19	Longest hairs on ANT III 0.75-1.0 × BD III. Dorsal body hairs pointed. SIPH 1.2-1.5 × cauda	…..Rhopalosiphum musae
–	Longest hairs on ANT III 0.4-0.6 × BD III. Dorsal body hairs short and blunt. SIPH 1.5- 1.9 × cauda	…..20
20	SIPH uniformly dark, cylindrical for most of length or with slight swelling of distal part, with a smooth distinctly constricted region subapically. Cauda dark	…..Rhopalosiphum padi
–	SIPH pale/dusky with darker apices, tapering gradually from base and with only slight subapical constriction. Cauda pale/dusky	…..Rhopalosiphum cerasifoliae
21	Dorsal body hairs long and spine-like	…..22
–	Dorsal body hairs short with pointed apices, or fan- or mushroom-shaped	…..23
22	Body elongate. Tergum entirely black	…..Atheroides hirtellus
–	Body oval. Tergum not black, ornamented with numerous small pointed denticles between the hair-bases	…..Sipha glyceriae
23	Body balloon-shaped, with eyes of only 3 facets, ANT and legs greatly reduced and SIPH absent. Faceted wax glands present on all segments	…..Colopha hispanica
–	Body elongate, with compound eyes and well-developed appendages. SIPH present, stump-like or raised pores. No faceted wax glands	…..24
24	Fore and mid tibiae thickened at base, forming a smooth sclerotic “patella” (clearly different from base of hind tibia). SIPH stump-shaped. ABD TERG 8 with a pair of large rounded tubercular processes, each bearing 2 long hairs	…..Saltusaphis scirpus
–	Fore and mid tibiae constricted at base like hind tibiae. SIPH as slightly raised pores. ABD TERG 8 enlarged, entirely sclerotic, without tubercular processes, semicircular or emarginate posteriorly	…..25
25	Dorsal hairs pointed. ABD TERG 8 with posterior margin rounded, not distinctly emarginate. ANT PT/BASE 0-5-0.6	…..Thripsaphis ballii
–	Dorsal hairs mushroom-shaped. ANT TERG 8 distinctly emarginate posteriorly. ANT PT/BASE 0.8-1.1	…..26
26	Dorsum usually with well-marked and clearly-defined pleural longitudinal dark stripes that run almost the full length of the body (with small breaks between segments); these stripes are almost as dark as the intersegmental muscle plates, and are either side of a very pale spinal region that has no trace of a darker spinal stripe. (Wholly dark forms also sometimes occur)	…..Subsaltusaphis ornata
–	Dorsum either almost unpigmented (except for muscle plates), or with ill-defined dark pleural longitudinal stripes or rows of paired patches that are paler than intersegmental muscle plates. When pleural bands are well-developed then there is also between them at least a trace of a dark spinal stripe. (Wholly dark forms are not known to occur)	…..Subsaltusaphis picta

(If specimens collected from Scirpus run to couplet 23, it would be advisable also to check that they are not one of the numerous other Carex-feeding Saltusaphidine species, by taking them through couplets 5-53 of key B to apterae on Carex.)

*Sciuro-hypnum*	Brachytheciaceae
*Sciuro-hypnum oedipodium*	Muscaphis escherichi; Pseudacaudella rubida

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

*Scleranthus*	Caryophyllaceae
*Scleranthus annuus*	Myzus persicae

*Scleria*	Cyperaceae
*Scleria cochinchinensis* = S. terrestris
*S. elata* = S. terrestris
*S. pilosissima*	Carolinaia caricis
*S. pterota* = S. melaleuca
*S. melaleuca*	Carolinaia caricis
*S. racemosa*	Aphis gossypii
*S. scandens*	Carolinaia caricis
*S. scrobiculata*	Carolinaia hillerislambersi
*S. terrestris*	Aulacorthum scirpi of Ghosh & Raychaudhuri 1972, nec. van der Goot

Key to apterae on Scleria:-

1	ANT tubercles well developed, their inner faces scabrous and parallel or slightly divergent. Tergum entirely dark. ANT c. 0.75-0.8 × BL	…..Aulacorthum scirpi of Ghosh & Raychaudhuri, 1972, nec. van der Goot*
–	ANT tubercles weakly developed. Tergum pale or dark. ANT 0.26-0.75 × BL	…..2
2	Dorsal cuticle strongly wrinkled or variolate. ANT 5- or 6-segmented, 0.26-0.33 × BL, with PT/BASE 1.0-1.5. SIPH pale/dusky, with very coarse imbrication, cylindrical for most of length and abruptly narrowing subapically	…..Carolinaia caricis
–	Dorsal cuticle smooth or almost smooth. ANT usually 6-segmented, 0.6-0.75 × BL, with PT/BASE 2.0-3.8. SIPH dark to blackish, tapering, with normal imbrication	…..3
3	ANT III with 2-4 rhinaria on swollen part near base. ANT PT/BASE c.3.75. R IV+V with 4 accessory hairs. ABD TERG 8 with 4 hairs. ABD TERG 1 and 7 without marginal tubercles	…..Carolinaia hillerislambersi
–	ANT III without rhinaria. ANT PT/BASE 2.0-3.2. R IV+V with 2 accessory hairs. ABD TERG 8 with 2 hairs. ABD TERG 1 and 7 with MTu	…..Aphis gossypii

*Sclerocarya*	Anacardiaceae
*Sclerocarya birrea* (incl. ssp. caffra)	Aphis craccivora, gossypii

–	Dorsum of thorax and abdomen widely sclerotized	….Aphis craccivora
–	Dorsum of thorax and abdomen membranous	….Aphis gossypii

Scleropodium see Pseudoscleropodium

Brachytheciaceae

*Scoliopus*	Liliaceae
*Scoliopus bigelovii*	Ericaphis scoliopi

*Scolopia*	Salicaceae
*Scolopia crenata*	Aphis (Toxoptera) aurantii; [Aphis sp.]
*S. ecklonii*	[Aphis sp.]; Myzus persicae

Use key to polyphagous aphids.

*Scolymus*	Asteraceae
*Scolymus grandiflorus* = S. hispanicus
*S. hispanicus*	Aphis fabae; Brachycaudus cardui, helichrysi; [Dysaphis lappae ssp. cynarae]; [Protaphis terricola]
*S. maculatus*	Aphis fabae, gossypii; Brachycaudus helichrysi; Capitophorus eleaegni
*Scolymus* sp.	Uroleucon aeneum

Use key to apterae on Carduus.

*Scoparia*	Plantaginaceae
*Scoparia dulcis*	Aphis gossypii

*Scorpiurus*	Fabaceae
*Scorpiurus muricatus*	Aphis craccivora; Myzus persicae
*S. sulcatus* = S. muricatus

Use key to polyphagous aphids.

*Scorzonera* (including Podospermum)	Asteraceae
*Scorzonera albicaulis*	Aphis fabae
*S. cana*	[Aphis medicaginis of Rusanova 1942 (= craccivora?)]
*S. hirsuta*	Aphis fabae; Brachycaudus tragopogonis
*S. hispanica*	Aphis fabae; Brachycaudus tragopogonis; Neomyzus circumflexus; Rhopalosiphoninus latysiphon
*S. humilis*	Aphis fabae; Brachycaudus tragopogonis; Uroleucon jaceae, scorzonerae
*S. iliensis*	[Protaphis carthami]
*S. laciniata*	Aphis fabae
*S. parviflora*	Aphis fabae; Brachycaudus tragopogonis; Protaphis aralensis
*S. pubescens*	Aphis craccivora; Brachycaudus tragopogonis
*S. purpurea*	Aphis fabae; Protaphis scorzonerae
*S. subaphylla*	Acyrthosiphon ghanii
*S. tau-saghyz*	Brachycaudus tragopogonis; Brachyunguis tausaghyz; Protaphis scorzonerae; Rectinasus buxtoni; Smynthurodes betae; [Titanosiphon neoartemisiae]
*S. tortuosissima*	Uroleucon tortuosissimae
*Scorzonera* spp.	[Anuraphis controversus Rusanova (nomen nudum)]; Aphis spiraecola; [Paracletus cimiciformis]; [Uroleucon pilosellae]

Key to apterae on Scorzonera:-

1	ANT PT/BASE less than 0.3. Body and appendages densely hairy. SIPH absent	…..2
–	ANT PT/BASE at least 0.5. Body and appendages not densely hairy. SIPH present	…..3
2	ANT 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
3	ANT tubercles developed but often low, with smooth, broadly divergent inner faces. ANT III with 1-85 rhinaria	…..4
–	ANT tubercles either undeveloped, or steep-sided and scabrous or spiculose. ANT III without rhinaria, or with only 1-2 small ones near base	…..8
4	SIPH pale or only dark at apices, and if with polygonal reticulation this is confined to distal 0.13-0.20 of length. ANT III with 1-11 rhinaria	…..5
–	SIPH dark, with polygonal reticulation on distal 0.17-0.40 of length. ANT III with 7-85 rhinaria	…..6
5	SIPH with a distal zone of polygonal reticulation. ANT III with 1-10 rhinaria on basal half. ANT PT/BASE 4.0-6.2	…..Macrosiphum euphorbiae
–	SIPH without distal polygonal reticulation. ANT III with 4-11 rhinaria in a row extending over 0.33-0.9 of length. ANT PT/BASE 2.5-3.5	…..Acyrthosiphon ghanii
6	Cauda pale. Dorsal abdomen without any pigmented sclerites. ANT III with 7-19 rhinaria (-30 in alatiform apt.). SIPH with polygonal reticulation on distal 0.3-0.4	…..Uroleucon tortuosissimae*
–	Cauda dark. Dorsal abdomen with pigmented scleroites at bases of hairs. ANT III with 16-54 rhinaria. SIPH with polygonal reticulation on distal 0.16-0.26	…..7
7	Tibiae mainly pale. Cauda with 10-17 hairs	…..Uroleucon scorzonerae
–	Tibiae entirely dark. Cauda with 22-28 hairs	…..Uroleucon jaceae
8	Dorsal abdomen with extensive dark sclerotisation comprising broad spino-pleural cross-bands or paired patches on ABD TERG 1-7, and separate marginal sclerites. Spiracular apertures rounded. Cauda helmet-shaped, less than 0.8 × its basal width	…..Brachycaudus tragopogonis
–	Dorsal abdomen pale or with a different pattern of sclerotisation. Spiracular apertures reniform. Cauda bluntly conical, tongue- or finger-shaped, 0.9-2.5 × its basal width	…..9
9	ANT PT/BASE within range 0.6-1.3. (SIPH and cauda both very short)	…..10
–	ANT BASE more than 1.5	…..go to key to polyphagous aphids
10	SIPH pale, c. 0.5-0.6 × cauda, which bears 6-8 hairs	…..Brachyunguis tausaghyz*
–	SIPH dark, 0.65-c.1 × cauda, which bears 7-18 hairs	…..11
11	SIPH 0.65-0.77 × cauda, which bears 16-18 hairs	…..Protaphis aralensis*
–	SIPH about equal in length to cauda, which bears 7-14 hairs	…..Protaphis scorzonerae

*Scorzoneroides*	Asteraceae
*Scorzoneroides autumnalis*	Aphis craccivora, fabae, gossypii, leontodontis, nasturtii, spiraecola, [taraxacicola]; Aulacorthum palustre, solani; Hyperomyzus lactucae; Myzus ascalonicus; Nasonovia ribisnigri; Protaphis middletonii; Trama caudata, troglodytes; Uroleucon cichorii, [grossum], hypochoeridis, leontodontis

Use key to apterae on Leontodon.

*Scrophularia*	Scrophulariaceae
*Scrophularia aquatica*	Myzus persicae
*S. buergeriana*	[Uroleucon gobonis]
*S. canina*	Aphis craccivora, gossypii, verbasci; Macrosiphum euphorbiae
*S. glabrata*	Aphis verbasci
*S. kiriloviana*	Aphis verbasci
*S. lanceolata*	Macrosiphum euphorbiae, [Macrosiphum sp. (Leonard 1974, 111)]
*S. leporella*	Macrosiphum euphorbiae
*S. nodosa*	Aphis nasturtii; [Hyalomyzus monardae (as Phorodon scrophulariae)]
*S. scorodonia*	[Cryptomyzus galeopsidis]
*S. vernalis*	Macrosiphum euphorbiae; Myzus persicae; Uroleucon scrophulariae
*Scrophularia* sp.	Aphis frangulae group

Key to apterae on Scrophularia:-

1	SIPH black with polygonal reticulation on about distal 0.2 of length. Cauda black. ANT III with 20-25 rhinaria	…..Uroleucon scrophulariae
–	SIPH pale or dark, if dark then without polygonal reticulation. Cauda pale or dark. ANT III with 0-10 rhinaria	…..2
2	R IV+V 1.6-1.9 × HT II. Cauda short and dark with 8-12 hairs	…..Aphis verbasci
–	Without that combination of characters	…..go to key to polyphagous aphids

*Scurrula*	Loranthaceae
*Scurrula atropurpurea*	Aphis (Toxoptera) aurantii; Greenidea rappardi; Sinomegoura citricola
*S. fusca*	Aphis (Toxoptera) aurantii; Greenidea rappardi
*S. korthalsii*	Tuberaphis loranthi
*S. philippensis* = S. atropurpurea
*Scurrula* sp.	Tuberaphis scurrulae, takenouchii

Use key to apterae on Loranthus.

*Scutellaria*	Lamiaceae
*Scutellaria altissima*	Aphis fabae, frangulae
*S. baicalensis*	Aphis gossypii
*S. catharinae*	Cryptomyzus alatavicus
*S. columnae*	[Aphis sp. (Italy; Cocuzza et al. 2014)]
*S. cordifrons*	Aphis gossypii
*S. discolor*	Myzus ornatus
*S. drummondii*	[Protaphis middletonii]
*S. galericulata*	[Aphis chloris of Wilson & Vickery 1918 (plant genus given in error as Scrophularia?]; Macrosiphum euphorbiae
*S. hastifolia*	Aulacorthum solani
*S. indica*	Aphis odorikonis
*S. lateriflora*	Pseudasiphonaphis corni
*S. mesostegia*	Aphis frangulae ssp. beccabungae, gossypii; Cryptomyzus alatavicus
*S. multiglandulosa*	Aphis gossypii
*S. regeliana*	Aphis gossypii
*S. repens*	Aphis gossypii
*S. scandens*	Aphis gossypii; [Brevicoryne brassicae]; Myzus ornatus
*S. sieversii*	Aphis gossypii; Cryptomyzus alatavicus
*S. transiliensis* = S. sieversii
*Scutellaria* spp.	[Aphis sp. (Davletshina 1964)]; Myzus sp. (India; BNMH collection, leg. K. Narayanan); Neomyzus circumflexus

Key to apterae on Scutellaria:-

1	SIPH as very small, rimless cones, shorter than their basal widths. ABD TERG 1-7 all with well-developed marginal tubercles (MTu), longer than SIPH. ANT hairs long and fine, 2-3 × BD III	…..Pseudasiphonaphis corni
–	Without that combination of characters	…..2
2	Dorsal body hairs long and capitate. ANT III with 10-37 rhinaria	…..Cryptomyzus alatavicus
–	Dorsal hairs not long and capitate. ANT III with 0-10 rhinaria	…..3
3	Head spiculose with inner faces of ANT tubercles converging anteriorly. ANT shorter than BL, without secondary rhinaria and with PT/BASE 1.7-3.0. Small, oval aphids, BL less than 2 mm. SIPH not clavate	…..4
–	Without that combination of characters	…..5
4	Dorsal abdomen with intersegmental pattern of dark ornamentation. ANT PT/BASE 1.7-2.5. SIPH weakly S-shaped with a well-developed flange, of diameter c.1.5 × the minimum diameter subapically	…..Myzus ornatus
–	Dorsum without dark intersegmental markings. ANT PT/BASE 2.7-3.0. SIPH straight with flange of diameter only 1.1-1.2 × minimum subapical diameter	…..Myzus sp., India
5	SIPH uniformly dark, not swollen. ABD TERG 1 and 7 with marginal tubercles (MTu)	…..6
–	SIPH (if present) pale or dark, or with dusky/dark apices, if wholly dark then markedly swollen. ABD TERG 1 and 7 without MTu	…..go to key to polyphagous aphids
6	Cauda black with 11-25 hairs. Dorsal abdomen usually with dark cross-bands on ABD TERG 7and 8 and dark markings anterior to SIPH	…..Aphis fabae
–	Cauda pale or dark with 5-12 hairs. Dorsal abdomen usually without dark markings	…..7
7	ANT usually 5-segmented, or with partial fusion of III and IV. R IV+V 0.9-1.1 × HT II	…..Aphis odorikonis
–	ANT usually 6 segmented (sometimes 5-segmented in summer dwarfs). R IV+V 1.1-1.5 × HT II	…..Aphis lamiorum or A. frangulae (incl. ssp. beccabungae) or A. gossypii (see text)

*Scutia*	Rhamnaceae
*Scutia buxifolia*	Aphis (Toxoptera) aurantii

*Searsia*	Anacardiaceae
*Searsia dentata*	Aphis gossypii
*S. pyroides*	Aphis gossypii

*Secale*	Poaceae
*Secale africanum*	Macrosiphum euphorbiae
*S. cereale*	Anoecia corni, vagans; Diuraphis noxia; Forda formicaria, marginata, pawlowae; Laingia psammae; Metopolophium dirhodum, festucae ssp. cerealium; Neomyzus circumflexus; Rhopalosiphum maidis, nymphaeae, oxyacanthae, padi; Schizaphis graminum, hypersiphonata; Sipha elegans, maydis; Sitobion akebiae, avenae, fragariae, miscanthi; Smynthurodes betae; Tetraneura ulmi
*S. sylvestre*	Schizaphis graminum; Sipha maydis; Rhopalosiphum maidis
Use key to apterae of grass-feeding aphids under Digitaria.

*Sechium*	Cucurbitaceae
*Sechium edule*	Aphis craccivora, fabae, gossypii, spiraecola; Aulacorthum solani, spinocaudatum; Myzus persicae; Pseudomegoura magnoliae, [nipponica]

Use key to aphids on Cucurbita.

*Securigera*	Fabaceae
*Securigera parviflora*	Acyrthosiphon pisum; Aphis craccivora
*S. varia*	Acyrthosiphon caraganae, pisum; Aphis coronillae, craccae, vineti; Therioaphis trifolii

Use key to apterae on Coronilla.

*Securinega* see Flueggea	Phyllanthaceae
*Securinega fluggeoides* = Flueggea suffruticosa
S. *fruticosa* = Flueggea suffruticosa?
*S. virosa* = Flueggea virosa

*Sedum*	Crassulaceae
*Sedum acre*	Aphis sedi
*S. aizoon*	Aphis sedi, sediradicis; Eriosoma moriokense
*S. alboroseum* = Hylotelephium erythrostictum
*S. album*	Aphis sedi; Nasonovia dasyphylli
*S. altissimum* = S. sediforme
S. amplexicaule	Aphis sedi
S. anacampseros	Brachycaudus sedi
*S. anglicum*	Aphis sedi; [Hyperomyzus lactucae]; Macrosiphum euphorbiae
*S. annuum*	Aphis sedi
*S. argutum* = S. telephium
*S. asiaticum* = Rhodiola heterodonta
*S. brevifolium*	Aphis sedi
*S. bupleuroides* = Rhodiola bupleuroides
*S. caeruleum*	Aphis sedi
*S. caucasicum* = S. maximum ssp. ruprechtii
*S. cepaea*	Aphis sedi
*S. dasyphyllum*	Aphis sedi; Nasonovia dasyphylli
*S. ewersii*	Aphis sedi
*S. fabaria* = S. telephium
*S. forsterianum*	Aphis sedi
*S. gracile*	Aphis sedi
*S. hirsutum*	Smynthurodes betae
*S. hispanicum*	Aphis sedi
*S. hybridum*	Aphis sedi
*S. iwarenge*	Aphis gossypii
*S. japonicum*	Aphis sedi, spiraecola; Brachycaudus helichrysi; Myzus persicae
*S. kamtschaticum*	Aphis [pomi], sedi; [Macrosiphoniella formosartemisiae]
*S. lanceolatum* = Amerosedum lanceolatum
*S. latifolium* = S. maximum
*S. maximowiczii*	Aphis sedi
*S. maximum* (incl. ssp. ruprechtii)	Aphis fabae, sedi; [Sitobion avenae]
*S. middendorfianum* = Phedimus middendorfianus
*S. ochroleucum*	Aphis sedi; Brachycaudus helichrysi
*S. pallescens* = Hylotelephium pallescens
*S. paniculatum* (?)	Aphis fabae
*S. polytrichoides*	Aphis sedi
*S. purpureum* = S. telephium
*S. reflexum* = S. rupestre
*S. roseum* = Rhodiola rosea
*S. rupestre*	Aphis fabae, gossypii, sedi, solenella, [Aphis sp. (Davletshina 1964)]
*S. sediforme*	Aphis sedi; [Dysaphis foeniculus]; Myzus persicae
*S. selskianum* = Phedimus selskianus
*S. sempervivoides* = Rosularia sempervivoides
*S. sieboldii*	Myzus persicae
*S. spectabile* = Hylotelephium spectabile
*S. spurium*	Aphis sedi; [Brachycaudus cardui]; Smynthurodes betae; [Tetraneura ulmi]
*S. stoloniferum*	Aphis sedi
*S. telephium*	Aphis fabae, gossypii, nasturtii, sedi, smirnovi; [Macrosiphum hellebori]
*S. telephium* ssp. maximum = S. maximum
*S. tenuifolium* = S. amplexicaule
*S. villosum*	[Myzus icelandicus]
*Sedum* spp.	Aphis acrita; [Brevicoryne brassicae]; Myzus [certus], ornatus; Neomyzus circumflexus; Eriosoma ulmi

Key to apterae on Sedum (and Sempervivum):-

1	ANT less than 0.33 × BL, with PT short and stumpy	…..2
–	ANT at least 0.4 × BL, with longer PT	…..3
2	SIPH present as large pores with partially sclerotised rims, ringed with hairs. Body and appendages sparsely hairy.Wax glands present, each consisting of a central facet surrounded by a ring of smaller facets	…..Eriosoma sp. (moriokense, ulmi)
–	SIPH absent. Body and appendages densely hairy. No discrete wax glands	…..Smynthurodes betae
3	Cauda very broadly rounded, much broader than long. SIPH stump-like, shorter than basal widths	…..Brachycaudus sedi
–	Cauda helmet-shaped, tongue- or finger-shaped. SIPH tubular, longer than their basal widths	…..4
4	Cauda helmet-shaped, a little shorter than its basal width. Spiracular apertures large and rounded	…..Brachycaudus helichrysi
–	Cauda tongue- or finger-shaped, distinctly longer than its basal width. Spiracular apertures usually reniform	…..5
5	ANT tubercles weakly developed. ABD TERG 1 and 7 with marginal tubercles (MTu)	…..6
–	ANT tubercles well developed. ABD TERG 1 and 7 without MTu	…..12
6	R IV+V c. 0.8 × HT II. (Al. with sec. rhin.distributed ANT III 32-40, IV 8-15, V 0-2)	…..Aphis acrita*
–	R IV+V 0.9-1.7 × HT II. (Al. with sec. rhin. distributed III 3-25, IV 0-2 (-10), V 0-1)	…..7
7	ABD TERG 2-4 or 2-6 as well as 1 and 7 with well-developed, hemispherical or conical MTu	…..8
–	ABD TERG 2-4 only sporadically with small papilliform MTu	…..9
8	R IV+V 1.5-1.7 × HT II, with (2-) 3-4 accessory hairs. Longest hairs on ANT III 1.2-1.8 × BD III	…..Aphis sediradicis*
–	R IV+V c. 1.2 × HT II, with 2 accessory hairs. Longest hairs on ANT III c.0.5 × BD III	…..Aphis smirnovi*
9	SIPH pale with dark apices	…..Aphis nasturtii
–	SIPH entirely dark	…..10
10	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	…..11
11	ANT PT/BASE 1.6-2.3. SIPH 0.8-1.5 × 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
12	Thoracic spiracular apertures much larger than abdominal ones . ANT III usually with numerous secondary rhinaria, and often some also on IV, or IV and V	…..13
–	Thoracic spiracular apertures similar in size to abdominal ones. ANT III with or without a few (1-10) rhinaria on basal part, none on IV or V	…..go to key to polyphagous aphids, starting at couplet 4
13	Cauda usually with 7 hairs, rarely 6, 8 or 9. ANT PT/BASE 7.0-11.4 (usually more than 8.4). ANT III with 5-36 rhinaria, IV and V with 0. SIPH without imbrication. Dorsal abdomen with paired intersegmental markings	…..Nasonovia ribisnigri
–	Cauda almost always with 5 hairs. ANT PT/BASE 3.6-8.4. Sec. rhin. distributed ANT III 10-42, IV 0-21, V 0-4. SIPH with some imbrication. Dorsal abdomen with extensive dark sclerotisation, fused between tergites to form a large dark patch	…..Nasonovia dasyphylli

*Selaginella*	Selaginellaceae
*Selaginella* sp.	Pentalonia nigronervosa

*Selenicereus*	Cactaceae
*Selenicereus grandiflorus*	Aphis craccivora, gossypii

*Selenipedium* see Phragmipedium	Orchidaceae
*Selenipedium vittatum* = Phragmipedium vittatum

*Selinum*	Apiaceae
*Selinum carvifolia*	Aphis fabae, selini; Aulacorthum solani; Cavariella aegopodii, [cicutae]; Dysaphis apiifolia, [crataegi]; Hyadaphis foeniculi; Semiaphis dauci, sphondylii
*S. pyrenaeum*	Cavariella aegopodii
*S. tenuifolium* = S. wallichianum
*S. wallichianum*	Acyrthosiphon moltshanovi (?); Dysaphis selinumi, [Dysaphis sp. (Chakrabarti 1972)]; [Hyalomyzus sp. (L.K. Ghosh 1977)]

Key to apterae on Selinum:-

1	ABD TERG 8 with a backwardly-directed process above the cauda, bearing 2 hairs. ANT PT/BASE 0.64-1.25	…..Cavariella aegopodii
–	No supracaudal process. ANT PT/BASE more than 2	…..2
2	SIPH very small, less than 0.6 × cauda, flangeless, and usually curved towards midline	…..Semiaphis spp.
–	SIPH more than 0.6 × cauda, with an apical flange	…..3
3	SIPH dark, clavate, 0.9-1.4 × cauda	…..Hyadaphis foeniculi
–	SIPH not as above	…..4
4	SIPH much shorter than HT II. ABD TERG 1-4 and 7 usually (?) with well-developed marginal tubercles (MTu)	…..Aphis selini*
–	SIPH longer than HT II. MTu present or absent	…..5
5	Cauda triangular or helmet-shaped (pentagonal), with 2-5 hairs. Spinal tubercles (STu) present on head and ABD TERG 8, or 7 and 8	…..6
–	Cauda tongue- or finger-shaped, usually bearing 7 or more hairs	…..7
6	Cauda triangular, 1.20-1.33 × its basal width, and bearing only 2-3 hairs. MTu often present on ABD TERG 2-4, but not 1 and 7	…..Dysaphis selinumi*
–	Cauda helmet-shaped/pentagonal, not longer than its basal width, with 5 hairs. MTu present on ABD TERG 1-5, and frequently also on ABD TERG 7	…..Dysaphis apiifolia
7	Head smooth with broadly divergent ANT tubercles. SIPH thin, tapering, pale, without subapical reticulation, 1.0-1.3 × the thick, pale cauda. R IV+V 0.6-0.7 × HT II	…..Acyrthosiphon moltshanovi
–	Without that combination of characters	…..go to key to polyphagous aphids

*Semenovia*	Apiaceae
*Semenovia rubtzovii*	Brachyunguis flexosiphon
*S. transiliensis*	Cavariella pastinacae

–	ANT PT/BASE less than 1.0. SIPH 0.5 × cauda or less. ABD TERG 8 without a supracaudal process	…..Brachyunguis flexosiphon
–	ANT PT/BASE more than 2.0. SIPH more than 2 × cauda. ABD TERG 8 with a supracaudal process	…..Cavariella pastinacae

(or go to key to apterae on Heracleum)

*Semiaquilegia*	Ranunculaceae
*Semiaquilegia adoxoides*	Aulacorthum solani

*Sempervivum*	Crassulaceae
*Sempervivum × funckii*	Aphis sedi
*S. globiferum*	Aphis sedi, [sempervivae]; Nasonovia ribisnigri
*S. heuffelii*	Nasonovia dasyphylli
*S. kosaninii*	Nasonovia ribisnigri
*S. soboliferum* = S. globiferum
*S. tectorum*	Aphis sedi; Macrosiphum euphorbiae
Sempervivum sp.	Aphis fabae; Nasonovia dasyphylli

See key to apterae on Sedum.

*Senebiera*	Brassicaceae
*Senebiera pinnatifidia* = Lepidium didymum

Senecio

Asteraceae

Note: many species formerly placed in Senecio are now placed in other genera, see on the beginning of the identification key.

*Senecio abrotanifolius* (incl. ssp. tiroliensis)	Aphis fabae; Aulacorthum solani; Rhopalosiphoninus staphyleae
*S. adonidifolius*	Aphis jacobaeae; Brachycaudus cardui; Seneciobium balachowskyi
*S. affinis*	Aphis craccivora
*S. alatus*	Brachycaudus helichrysi
*S. alpinus*	Brachycaudus cardui; Macrosiphum alpinum
*S. ambavilla*	Aphis gossypii
*S. angulatus*	Macrosiphum euphorbiae
*S. anonymus*	Uroleucon ambrosiae, pseudambrosiae
*S. anthemidiphyllus*	Aphis senecionicoides
*S. aquaticus* (incl. ssp. barbareifolius)	Aphis fabae; Brachycaudus cardui, helichrysi
*S. arenarius*	Brachycaudus cardui
*S. argophylloides*	Aphis lugentis
*S. argunensis*	Brachycaudus cardui
*S. asiaticus* = Tephroseris praticola
*S. atratus*	Aphis lugentis
*S. aureus* (= Packera aurea)	Aphis gossypii, lugentis; Macrosiphum euphorbiae, pallidum; Pemphigus sp. (as lactucae); Uroleucon [eupatoricolens], pseudambrosiae
*S. barbertonicus*	Aphis gossypii
*S. biafrae* = Solanecio biafrae
*S. bicolor* (?)	Aphis fabae, spiraecola; Brachycaudus cardui
*S. bicolor* ssp. cineraria = Jacobaea maritima
*S. bonariensis*	Aphis fabae
*S. borysthenicus*	Aphis jacobaeae
*S. bracteolatus*	Aphis papillosa; Pehuenchaphis agilissima; Uroleucon capitophoroides
*S. brasiliensis*	Brachycaudus helichrysi; Macrosiphum euphorbiae
*S. cacaliaster*	Aphis cacaliasteris, jacobaeae
*S. campestris* = Senecio integrifolius
*S. cannabifolius*	Aphis fabae; Aulacorthum solani; Brachycaudus helichrysi; Uroleucon sonchi (ssp. afghanicum?)
*S. canus* (= Packera cana)	Aphis lugentis, senecionis; Aulacorthum solani; Brachycaudus helichrysi
*S. cappa*	Aphis gossypii; Brachycaudus helichrysi
*S. carpetanus*	Aphis cacaliasteris (as ssp. helvetica)
*S. chrysanthemoides*	[Aphis verbasci]; Brachycaudus helichrysi
*S. cineraria* = Jacobaea maritima
*S. confusus*	Aphis spiraecola; Aulacorthum solani; Macrosiphum euphorbiae; Myzus persicae; [Rhodobium porosum]; Uroleucon ambrosiae
*S. consanguineus* (incl. var. major)	Hyperomyzus carduellinus; Macrosiphum euphorbiae
*S. cordatus* = Senecio alpinus
*S. coronatus*	[Aphis sp. (Millar 1994)]
S. covasii	Aphis papillosa
*S. crassifolius* = Senecio leucanthemifolius
*S. cruentus* see Cineraria cruenta
*S. densiflorus* = Senecio cappa
*S. didentatus* (?)	Brachycaudus cardui
*S. diversifolius* = Senecio raphanifolius
*S. doria* (incl. ssp. laderoi)	Aphis fabae, jacobaeae; Aulacorthum solani; Brachycaudus cardui; Myzus ascalonicus
*S. doronicum*	Allocotaphis quaestionis
*S. dryadeus*	Brachycaudus helichrysi
*S. dubius*	Brachycaudus cardui ssp. turanica, helichrysi; Uroleucon bicolor, [Uroleucon (Uromelan) sp., Kazakhstan; Kadyrbekov 2009b, 2014d)]
*S. elegans*	Brachycaudus helichrysi; Myzus persicae
*S. erraticus* = Senecio aquaticus ssp. barbareifolius
*S. erucifolius* (incl. ssp. arenaria)	Aphis jacobaeae; Brachycaudus cardui; Uroleucon cichorii
*S. filaginoides*	Aphis gossypii, lugentis, papillosa, pulverea, senecionicoides; Brachycaudus helichrysi; Pehuenchaphis agilissima
*S. flavus*	[Acyrthosiphon pisum]; Hyperomyzus lactucae; Myzus persicae
*S. fluviatilis* = Senecio nemorensis
*S. fuchsii* = Senecio ovatus
*S. fulgens*	Myzus persicae
*S. gallicus*	Aphis fabae, jacobaeae, lugentis; Brachycaudus cardui, helichrysi, lateralis; Macrosiphum euphorbiae
*S. gilliesii*	Aphis lugentis, papillosa; Brachycaudus helichrysi; Pehuenchaphis agilissima; Uroleucon capitophoroides
*S. glabellus* (= Packera glabella)	Aphis lugentis
*S. glomeratus*	Aphis sp. (California, BMNH collection)
*S. goldsacki*	Aphis senecionicoides
*S. grandidentatus* = Senecio erucifolius ssp. arenaria
*S. heracleifolius* = Roldana heracleifolia
*S. heritieri* = Pericallis lanata
*S. huntii* = Brachyglottis huntii
S. × hybridus see Cineraria cruenta
*S. hydrophilus*	Aphis lugentis
*S. ilicifolius*	Brachycaudus helichrysi
*S. inaequidens*	Aphis gossypii, nerii; Brachycaudus helichrysi
*S. integerrimus*	Brachycaudus helichrysi
*S. integrifolius*	Aphis fabae, lugentis; Brachycaudus cardui; Uroleucon seneciocola
*S. jacobaea*	Aphis fabae, jacobaeae, lugentis, nasturtii; Aulacorthum solani; Brachycaudus cardui, helichrysi, lateralis; Cedoaphis maxsoni; Eriosoma patchiae; [Geoica utricularia]; [Macrosiphoniella subterranea]; Macrosiphum euphorbiae; [‘Macrosiphum jacobaeabalsamita’ (Rafinesque) of Hottes (1931)]; Myzus persicae; Protaphis terricola; Uroleucon cirsicola, [cirsii, ] dzhungaricum, sonchi, syrdariense
*S. jacquinianus* = Senecio nemorensis ssp. jacquinianus
*S. kaempferi* = Farfugium japonicum
S. laderoi = Senecio doria ssp. laderoi
*S. leucanthemifolius* (incl. ssp. vernalis)	Aphis craccivora, fabae; Brachycaudus cardui, helichrysi; Macrosiphum euphorbiae; Myzus persicae
S. leucostachys	Aphis lugentis; Brachycaudus cardui
*S. lineatus*	Aphis gossypii
*S. linifolius*	Aphis fabae; Brachycaudus cardui
*S. littoralis*	Aphis gossypii
S. lividus	Myzus persicae
*S. lugens*	Aphis lugentis
*S. lyratipartus* (?)	Hyperomyzus carduellinus
*S. macrophyllus*	Aphis cacaliasteris, jacobaeae
*S. madagascariensis*	Aphis gossypii; Brachycaudus helichrysi; Macrosiphum euphorbiae
*S. maeviae*	Uroleucon capitophoroides
*S. megaglossus*	[Aphis sp. (Leonard 1972a, 104)]; Macrosiphum euphorbiae; Myzus persicae
*S. microglossus*	Macrosiphum euphorbiae; Myzus persicae
*S. mikanioides*	Aphis fabae, gossypii; Aulacorthum solani; Brachycaudus helichrysi; Eriosoma patchiae; Macrosiphum euphorbiae; Myzus persicae
*S. nebrodensis*	Myzus ornatus
S. nemoralis	[‘Macrosiphum jacobaeabalsamita’ (Rafinesque) of Hottes (1931)]
*S. nemorensis* (incl. jacquinianus)	Allocotaphis quaestionis; Aphis cacaliasteris, fabae, jacobaeae, seneciocrepiphaga; Aulacorthum solani; Brachycaudus cardui, helichrysi, virgatus; Myzus ornatus, persicae; Uroleucondzhungaricum
*S. othonnae*	Brachycaudus cardui; Uroleucon sonchi
*S. ovatus*	Aphis cacaliasteris; Brachycaudus cardui, helichrysi, lateralis; Macrosiphum alpinum; [Uroleucon gobonis]
*S. oxyodontus*	Brachycaudus helichrysi
*S. paludosus*	Nasonovia ribisnigri
*S. pauperculus*	Aphis duckmountainensis
*S. petasitis* = Roldana petasitis
*S. phryganthemoides* (?)	Brachycaudus helichrysi
*S. pierotii*	Uroleucon seneciocola
*S. pinnulatus*	Aphis craccivora, gossypii
*S. plattensis* (= Packera plattensis)	Aphis lugentis
*S. polyphlebius*	Aphis aurantii, spiraecola; Uroleucon ambrosiae
*S. pratensis* = Senecio integrifolius
*S. praticola* = Tephroseris praticola
*S. pseudoarnica*	Aphis fabae, [sambuci], seneciocrepiphaga
S. pseudoelegans	Brachycaudus helichrysi; Myzus persicae
S. pyrenaicus	Aphis haroi; Brachycaudus cardui
*S. quadridentatus*	Brachycaudus helichrysi
*S. radicans*	Myzus persicae
*S. raphanifolius*	Brachycaudus helichrysi
*S. rigidus*	Brachycaudus helichrysi
*S. rivularis* = Tephroseris crispa
*S. rufinervis*	Aphis fabae, nasturtii; Indomasonaphis anaphalidis
*S. rupestris* = Senecio squalidus ssp. rupestris
*S. salicifolia*	Brachycaudus helichrysi
S. salignus	Uroleucon artemisiae
*S. sarracenicus* = Senecio nemorensis
*S. scandens*	[Astegopteryx xinglongensis]; Brachycaudus helichrysi; [Greenidea longicornis]; Indomasonaphis anaphalidis
*S. scopulinus*	Aphis lugentis; Protaphis middletonii
*S. serra*	Aphis lugentis; Aphis sp. (Idaho, BMNH collection, leg. G.F. Knowlton)
*S. serrulatus* var. gracilis	Aphis gossypii
*S. setulosus*	Brachycaudus helichrysi
*S. siculus* = Senecio squalidus ssp. microglossus
*S. smallii* = Senecio anonymus
*S. smithii*	Myzus ornatus; [Uroleucon nuble]
*S. sonchifolius* see Emilia sonchifolia
*S. spartioides*	Aphis lugentis, senecioradicis
*S. squalidus* (incl. sspp. microglossus, rupestris)	Brachycaudus cardui, helichrysi, lateralis; Macrosiphum euphorbiae
*S. stapeliiformis* = Kleina stapeliiformis
*S. stenocephalus* = Ligularia stenocephala
*S. suaveolens*	Brachycaudus cardui
*S. subalpinus*	Aphis cacaliasteris; Brachycaudus cardui, helichrysi
*S. subulatus*	Aphis lugentis, papillosa, senecionicoides; Uroleucon capitophoroides
*S. subumbellatus*	Aphis conspicua, gossypii, intrusa, lugentis, malalhuina, papillosa, paradoxa, senecionicoides; Blanchardaphis poikila; Pehuenchaphis agilissima; Uroleucon capitophoroides
*S. sylvaticus*	Aphis cacaliasteris; Brachycaudus cardui, helichrysi; Protaphis terricola
*S. taraxacifolius* = Iranecio taraxacifolius
*S. tenuifolius*	Aphis odinae, spiraecola; Brachycaudus helichrysi; Neomyzus circumflexus; Uroleucon compositae? (as solidaginis)
*S. tiroliensis* = Senecio abrotanifolia ssp. tiroliensis
*S. tomentosus*	Protaphis middletonii
*S. tournefortei* = Senecio pyrenaicus
*S. triangularis*	Aphis lugentis
*S. triligulatus*	[Capitophorus formosartemisiae]
*S. trineurus* = Leonis trineura
S. uintahensis	Macrosiphum pallidum
*S. umbrosus*	Brachycaudus helichrysi
*S. uspallatensis*	Aphis papillosa
*S. vernalis* = Senecio leucanthemifolius ssp. vernalis
*S. viscosus*	Brachycaudus cardui, helichrysi, lateralis; Macrosiphum euphorbiae, [stellariae]; [Uroleucon (Uromelan) sp. (as jaceae)]
*S. vulgaris*	Acyrthosiphon malvae; Aphis cacaliasteris, fabae, gossypii, jacobaeae, solanella; Aulacorthum solani; Brachycaudus cardui, helichrysi, lateralis, [prunicola]; Macrosiphum euphorbiae, [stellariae]; Myzus ascalonicus, ornatus, persicae; Neomyzus circumflexus; Uroleucon ambrosiae, sonchi, [Uroleucon (Uromelan) sp. (as jaceae)]
*S. yegua*	Uroleucon muermosum
*Senecio* spp.	Acyrthosiphon rubi; [Anoecia corni]; Aphis sp. nr lugentis (Utah, BMNH collection); Aphis (Toxoptera) aurantii, pulverea; Blanchardaphis capitophoroides; Eumyzus nokuli; Euthoracaphis longisetosa; [Nipponaphis sp.]; [Rhopalosiphum nymphaeae]; Ucrimyzus villalobosi; Uroleucon capitophoroides, compositae, erigeronense, formosanum, [zerogutierrezis]

Key to apterae on Senecio (including Acrisione, Delairea, Jacobaea, Oldfeltia, Packera, Pericallis, Pseudogynoxys, Roldana, Solenecio and Tephroseris):-

1	Body aleyrodiform, subcircular, heavily sclerotised, dark, with reduced appendages, and with numerous long fine dorsal and marginal hairs	…..Euthoracaphis longisetosa
–	Body of normal aphid form	…..2
2	ANT less than 0.33 × BL, with ANT PT/BASE less than 0.7. Dorsal wax glands evident. SIPH absent or as large pores. Cauda broadly rounded, not evident	…..3
–	ANT more than 0.33 × BL, with ANT PT/BASE more than 0.7. No discrete wax glands. SIPH absent, poriform, conical or tubular. Cauda not broadly rounded	…..4
3	SIPH present as large pores with partially sclerotised rims, ringed with hairs. Wax glands present on all segments, each generally comprising a ring of facets around a central pore	…..Eriosoma patchiae
–	SIPH absent. Wax glands only on all or some of ABD TERG 3-7 and comprising pore-plates of uniform small polygonal facets	…..Pemphigus sp.
4	Cauda helmet-shaped or bluntly triangular, not or hardly longer than its basal width	…..5
–	Cauda triangular, tongue- or finger-shaped, usually much longer than its basal width	…..12
5	SIPH pale or slightly dusky, or darker only distally	…..6
–	SIPH uniformly dusky or dark	…..7
6	Cauda black. SIPH densely imbricated. Dorsal abdomen with extensive dusky sclerotisation, and numerous rigid hairs with tuberculate bases, some of them having furcate apices, longest hairs being 3.0-3.6 × ANT BD III	…..Eumyzus nokuli*
–	Cauda pale. SIPH almost smooth. Dorsal abdomen unsclerotised, with hairs sparse, without tuberculate bases or furcate apices, and much shorter	…..Brachycaudus helichrysi
7	SIPH 0.4-1.3 × the bluntly triangular cauda. ANT PT/BASE 0.7-1.4	…..Protaphis terricola
–	SIPH more than 1.8 × cauda. ANT PT/BASE more than 2	…..8
8	Dorsal abdomen with variably developed transverse dark sclerotic bars, not or only partially fused between tergites and often interrupted in midline on ABD TERG 1-4	…..9
–	Dorsal abdomen with an extensive solid black shield covering ABD TERG 1-6	…..10
9	Cuticle of head densely spiculose. ANT III with (0-)12-30 secondary rhinaria distributed over most of length, and ANT IV with 0-16. Spiracular apertures small, and marginal tubercles (MTu) not evident	…..Cedoaphis maxsoni
–	Cuticle of head without spinules. ANT without secondary rhinaria rhinaria (except in alatiform specimens). Spiracular apertures large and rounded. Marginal tubercles (MTu) often present on ABD TERG 2-4, and sometimes on 1 and/or 5	…..Brachycaudus virgatus
10	SIPH long and thin, more than 5 × cauda, which bears more than 20 hairs. ANT with numerous secondary rhinaria on III (distal part), IV and V. ANT PT/BASE more than 6	…..Allocotaphis quaestionis
–	SIPH 2.1-3.4 × cauda which bears 6-8 hairs. ANT without secondary rhinaria (except in alatiform specimens, and then only on III). ANT PT/BASE 3.2-5.1	…..11
11	Hairs on ABD TERG 8 are 30-61 µm long. Longest hairs on hind femur 10-25µm long	…..Brachycaudus lateralis
–	Hairs on ABD TERG 8 are at least 70µm long. Longest hairs on hind femur more than 25µm long	…..Brachycaudus cardui
12	SIPH absent, or present as small black sclerotic cones shorter than their basal widths	…..13
–	SIPH conical or tubular, as long as or longer than their basal widths	…..15
13	SIPH absent. Marginal tubercles (MTu) always present on ABD TERG 1, 6 and 7, and often also on 2-4. ANT PT/BASE 1.6-2.0, R IV+V 1.05-1.25 × HT II	…..Seneciobium balachowskyi
–	SIPH as black sclerotic cones, shorter than their basal widths. MTu differently distributed, never on ABD TERG 6. ANT PT/BASE 1.2-1.8. R IV+V either 0.75-0.85 × or 1.7-1.8 × HT II	…..14
14	Tergum mainly pale and membranous. ANT III with 12-35 hairs, the longest 0.9-3.0 × BD III. ANT III and IV both with rhinaria. R IV+V 1.5-1.8 × HT II, longer than PT. MTu consistently on ABD TERG 1-4, but rarely on 7. SIPH placed on anterior part of ABD TERG 6	…..Pehuenchaphis agilissima
–	Tergum with variable dark sclerotisation. ANT III with 3-14 hairs, the longest 0.7-1.2 × BD III. ANT III and IV without rhinaria. R IV+V 0.8-1.0 × HT II, shorter than PT. MTu on ABD TERG 1 and 7. SIPH placed (as normal) on ABD TERG 5	…..Aphis malalhuina
15	Marginal tubercles (MTu) present on ABD TERG 1, and usually also (at least) on ABD TERG 7. SIPH dark, without polygonal reticulation	…..16
–	MTu absent from ABD TERG 1 and 7, and only irregularly on 2-6. SIPH pale or dark, with or without a distal zone of polygonal reticulation	…..31
16	Tibiae entirely dark. ANT III-IV (-V) with sec. rhinaria, with almost always more rhinaria on IV than on III	…..17
–	Tibiae mainly pale, dark only distally. ANT III and IV with or without rhinaria, but if there are any on III then there are always fewer on IV	…..25
17	MTu present regularly on ABD TERG 2-4 as well as 1 and 7	…..18
–	MTu only consistently present on ABD TERG 1 and 7	…..19
18	R IV+V with 4-8 accessory hairs. SIPH 0.55-0.8 × cauda	…..Aphis senecioradicis
–	R IV+V with 2 (-3) accessory hairs. SIPH 1.4-2.3 × cauda	…..Aphis jacobaeae
19	ANT III with acute hairs 12-54 μm long, 0.7-1.1(-2.1) × BD III. ANT BASE VI 0.09-0.15 mm but rarely exceeding 0.135 mm. ABD TERG 2-4 without MTu. Anterior half of subgenital plate usually with 2-6 hairs (mode 3-4), but populations with 4-12 (mode 5-6) occur. SIPH 1.1-1.6 (mostly 1.2-1.5) × cauda	…..20
–	ANT III with fine-pointed hairs 32-58 μm long, (1.1-)1.4-3.3 × BD III. ANT BASE VI 0.124-0.20 mm, when less than 0.14 then cauda about equal in length to SIPH. ABD TERG 2-4 with or without some MTu. Anterior half of subgenital plate with 5-20 hairs	…..21
20	Cauda tongue-shaped, parallel-sided or weakly tapering for much of length and broadly rounded at apex. ANT PT/BASE 1.4-2.4, mostly 1.6-2.1	…..Aphis lugentis
–	Cauda tapering to an almost pointed apex. ANT PT/BASE 1.35-1.55	…..Aphis senecionis
21	R IV+V with 2-4 (-5) accessory hairs (examine several specimens)	…..22
–	R IV+V with 2 accessory hairs	…..23
22	ABD TERG 2-4 each with (4-) 5-10 marginal hairs on each side. Cauda with 14-20 hairs	…..Aphis cacaliasteris
–	ABD TERG 2-4 each with 2-4 marginal hairs on each side. Cauda with 9-17 hairs	…..Aphis haroi
23	SIPH 1.1-1.55 × cauda. ANT PT/BASE 1.35-1.55. ABD TERG 2-4 sporadically with MTu	…..Aphis sp. (Idaho, BMNH collection, leg. G.F. Knowlton)
–	SIPH 0.95-1.1 × cauda. ANT PT/BASE 1.6-1.95. ABD TERG 2-4 without MTu	…..24
24	Sec. rhinaria. distributed ANT III 3-26, IV 10-20, V 0-6	…..Aphis duckmountainensis
–	Sec. rhinaria distributed ANT III 0-4, IV 1-10, V 1-5	…..Aphis seneciocrepiphaga*
25	MTu present on ABD TERG 1-4 (-6) and 7 of most specimens. SIPH 0.4-0.9 × cauda. ANT PT/BASE 1.0-2.0	…..26
–	MTu only regularly present on ABD TERG 1 and 7. SIPH 0.4-2.5 × cauda. ANT PT/BASE 1.3-4.5	…..28
26	SIPH 0.9–1.6 × cauda. Longest hair on ANT III 22-50 µm and 1.3-2.5 × BD III. MTu big	….Aphis conspicua
–	SIPH 0.4–0.9 ×cauda. Longest hair on ANT III 7-15 µm and 0.4-1.7 × BD III. MTu big or small	….27
27	MTu very variable in size (and sometimes even absent); often very large on prothorax and ABD TERG 1-4, but smaller and often absent from ABD TERG 5, 6 and even 7. Longest hairs on ANT III 0.6-1.7 × BD III	…..Aphis papillosa
–	MTu consistently present on prothorax and ABD TERG 1-4 and 7, sometimes also on 5 and 6; all of similar size. Longest hairs on ANT III 0-4-0.9 × BD III	…..Aphis senecionicoides
28	ANT PT/BASE 1.2-1.9. Abdominal dorsum with cross-bands	….Aphis pulverea
–	ANT PT/BASE usually 1.9 times at least, if exceptionally not so long, then ABD. 2–6 widely sclerotized, usually with discal plate (specimens A. craccivora), or cauda carry at least 7 ST (specimens of A. fabae, A. solanella and A. spiraecola)	….29
29	ABD TERG 2-5 with a large dark sclerotic patch, sometimes with small perforations intersegmentally	…..30
–	ABD TERG 2-5 membranous or with only small scattered sclerites, or with broad cross-bands leaving large intersegmental spaces	……go to key to polyphagous aphids, starting at couplet 25
30	ANT III with 0-7 rhinaria. (ANT III of al. with 10-13 rhinaria)	…..Aphis intrusa
–	ANT III without rhinaria, except in alatiform specimens. (ANT III of al. with 3-10 rhinaria)	…..Aphis craccivora
31	ANT tubercles undeveloped. ANT PT/BASE 1.3-1.9	…..32
–	ANT tubercles moderately to well developed. ANT PT/BASE 1.7-11.4	…..33
32	SIPH 0.33-0.62 × cauda. ABD TERG 8 with 2 (-4) hairs	…..Aphis paradoxa
–	SIPH 1.2-1.5 × cauda. ABD TERG 8 with 10-18 hairs	…..Aphis sp. nr lugentis (Utah, BMNH collection)
33	SIPH with a distal zone of polygonal reticulation (at least 4-5 rows of closed polygonal cells)	…..34
–	SIPH without a distinct distal zone of polygonal reticulation (but sometimes with 1-3 indistinctly defined rows of cells)	…..52
34	First tarsal segments with 3 hairs. SIPH pale or dusky, or at least usually with a pale section at base, with a well-defined polygonal reticulation on distal 0.1-0.2 of length, often on a somewhat constricted section, and comprising large cells of max, diam, more than 0.25 × width of SIPH at that point	…..35
–	First tarsal segments with 5 hairs. SIPH entirely dark, or paler only in middle, usually with polygonal reticulation on distal 0.16-0.4 of length, comprising numerous small cells of max. diam. less than 0.25 × width of SIPH at that point, usually on distal 0.16-0.4 of length	…..37
35	SIPH mainly dark, usually with pale bases. Tibiae mainly dark	…..Macrosiphum pallidum
–	SIPH and tibiae pale, or dark only at apices	…..36
36	BL 4.3-4.8 mm. ANT III with 6-17 rhinaria (al. with 20-30). Femora and SIPH with dark brown-black apices	…..Macrosiphum alpinum
–	BL 2.0-4.0 mm. ANT III with 1-7 (-10) rhinaria (al. with 12-21). Femora and SIPH pale or dusky at apices	…..Macrosiphum euphorbiae
37	Cauda almost as dark as SIPH, which are entirely pigmented	…..38
–	Cauda distinctly paler than SIPH, or of their most pigmented parts	…..43
38	R IV+V long and narrow, 1.5-1.7 × HT II	…..Uroleucon muermosum
–	R IV+V 0.7-1.4 × HT II	…..39
39	Tibiae wholly dark. Hind femora with basal half pale and distal half dark, with a rather sharp transition between. SIPH 1.4-1.8 × cauda, which bears 18-30 hairs	…..40
–	Tibiae with paler middle section. Hind femora pale on basal 0.2-0.5 of length. SIPH 1.5-2.1 × cauda, which bears 10-23 hairs	…..41
40	ANT PT 0.67-0.77 × ANT III. ANT PT/BASE 3.9-4.2. SIPH 1.65-1.9 × cauda	…..Uroleucon syrdariense
–	ANT PT 0.8-1.2 × ANT III. ANT PT/BASE 4.0-6.2. SIPH 1.3-1.8 × cauda	…..Uroleucon jaceae
41	ANT III with 60-80 secondary rhinaria distributed over 0.7-0.9 of its length	…..Uroleucon compositae
–	ANT III with 20-37 rhinaria not extending beyond basal 0.6 of length	…..42
42	SIPH 1.7-2.1 × cauda	…..Uroleucon seneciocola
–	SIPH 1.5-1.8 × cauda	…..Uroleucon dzhungaricum*
43	SIPH distally pigmented and basally pale. Cauda with one or more distal hairs short and blunt or capitate	…..Uroleucon erigeronense
–	SIPH entirely pigmented or with mid section paler. Caudal hairs all normal	…..44
44	ANT III 1.5-2.0 × longer than ANT IV + V together, and bearing 96-135 strongly protruberant rhinaria	…..Uroleucon formosanum
–	ANT III less than 1.2 × ANT IV + V together, and usually bearing less than 95 rhinaria	…..45
45	Crescent-shaped antesiphuncular sclerites present. ANT III with 56-97 rhinaria extending over 0.85-0.97 of length	…..Uroleucon cichorii
–	Antesiphuncular sclerites absent or vestigeal. ANT III with 8-36 rhinaria extending over 0.3-0.7 of length	…..46
46	SIPH with reticulation extended on distal 0.15 of length at most, with bad defined cells	…..Uroleucon capitophoroides
–	SIPH with reticulation on distal 0.16 at least, with well-defined cells	…..47
47	SIPH with reticulation on distal 0.41-0.60 of length	…..Uroleucon mexicanum
–	SIPH with reticulation on distal 0.16-0.36 of length	…..48
48	SIPH 1.1-1.5 × cauda, with reticulation on distal 0.25-0.36 of length. Coxae pale	…..49
–	SIPH 1.4-2.1 × cauda, with reticulation on distal 0.16-0.27 of length. Coxae pale, dusky or dark	…..50
49	HT II rather long and thin, 6 or more × longer than its maximum thickness and 0.9-1.1 × R IV+V	…..Uroleucon pseudambrosiae
–	HT II less than 5 × its maximum thickness and 0.70-0.85 × R IV+V	…..Uroleucon ambrosiae
50	R IV+V 1.2-1.8 × HT II. Cauda with 30-45 hairs	…..Uroleucon cirsicola
–	R IV+V 0.8-0.9 × HT II. Cauda with 23-34 hairs	…..51
51	Dorsal abdominal hairs with somewhat expanded apices and all with dark scleroites at bases. Coxae pale, concolorous with trochanters and bases of femora	…..Uroleucon bicolor
–	Dorsal abdominal hairs pointed and mostly without dark scleroites at bases. Coxae dusky/dark in comparison with trochanters and bases of femora	…..Uroleucon sonchi
52	Head densely spiculose, with steep-sided or apically convergent ANT tubercles	…..go to key to polyphagous aphids, starting at couplet 5
–	Head without spicules, or with few only on ventral side. Inner faces of ANT tubercles divergent	…..53
53	SIPH clavate	…..54
–	SIPH tapering/cylindrical	…..57
54	Cauda bearing 35-60 hairs. ANT III without rhinaria. Dorsal hairs long, with expanded apices, those on ABD TERG 3 being much longer than ANT BD III	…..Indomasonaphis anaphalidis
–	Cauda with 6-10 hairs. ANT III with 1-30 rhinaria. Dorsal hairs short and blunt, shorter than ANT BD III	…..55
55	Prothoracic spiracular apertures not much larger than those on abdomen. Hairs on ABD TERG 8 are 8-20 μm long. Secondary rhinaria only on ANT III (1-20). ANT PT/BASE 5.3-8.2. Alata without any dorsal abdominal dark patch	…..Ucrimyzus villalobosi
–	Prothoracic spiracular apertures much larger than those on abdomen, which are reniform. Hairs on ABD TERG 8 are 8-50 μm long, but if less than 20 μm long then secondary rhinaria are distributed ANT III 11-29, IV 0-16, V 0 (-9), and ANT PT/BASE 4.3-5.6. Alata with a dorsal abdominal (imperfect) patch	…..56
56	Hairs on ABD TERG 8 are 8-19 μm long, and on ANT tubercles 6-11 μm. Secondary rhinaria distributed ANT III 11-29, IV (0)-1-16, V 0 (-9). ANT PT/BASE 4.3-5.6. ANT PT 1.6-2.3 × cauda	…..Hyperomyzus carduellinus
–	Hairs on ABD TERG 8 are 30-50 μm long, and on ANT tubercles 18-30 μm. Secondary rhinaria distributed ANT III 4-20, IV 0 (-1), V 0. ANT PT/BASE 4.8-7.4. ANT PT 2.0-3.0 × cauda	…..Hyperomyzus lactucae
57	SIPH entirely dark, rather coarsely imbricated, with 1-3 poorly-defined rows of polygonal reticulation at apices. First tarsal segments with 5 hairs	…..Uroleucon capitophoroides
–	SIPH pale, sometimes with dusky/dark apices, without any subapical reticulation. First tarsal segments with 3 hairs	…..58
58	Thoracic spiracles enlarged, much larger than abdominal spiracles. ANT PT/BASE 7.0-11.4, usually more than 8.0. Hairs on ANT III 0.7-1.1 × BD III. Dorsum usually with paired dark intersegmental markings	…..Nasonovia ribisnigri
–	Thoracic spiracles similar in size to abdominal ones. ANT PT/BASE less than 7.5. Hairs on ANT III less than 0.7 × BD III. Dorsum without any dark markings	…..59
59	Tergum pale but sclerotic; rugose, papillated or strongly wrinkled. R IV+V 0.87-1.13 × HT II	…..Acyrthosiphon rubi
–	Tergum membranous, smooth or only slightly wrinkled. R IV+V 1.0-1.5 × HT II	…..Acyrthosiphon malvae group

Senecioides see Vernonia

Asteraceae

*Senna*	Fabaceae
*Senna alata*	Aphis craccivora, spiraecola
*S. aphylla*	Aphis gossypii, mirabilis
*S. benitoensis*	Aphis gossypii
*S. bicapsularis*	Myzus persicae
*S. corymbosa*	Aphis craccivora, fabae; Myzus persicae
*S. didymobotrya*	Aphis gossypii; Aulacorthum solani; Myzus antirrhinii, persicae
*S. hirsuta* (incl. var. leptocarpa)	Aphis craccivora, fabae, gossypii
*S. leiophylla*	Aphis gossypii; Myzus persicae
*S. obtusifolia*	Aphis gossypii
*S. occidentalis*	Aphis craccivora, gossypii, spiraecola
*S. septemtrionalis*	Aphis craccivora, fabae, gossypii
*S. siamea*	Aphis craccivora; [Kurisakia yunnanensis]
*S. singueana*	Aphis gossypii
*S. sophera*	Aphis gossypii
S. sulfurea	Aphis (Toxoptera) aurantii
*S. surattensis*	Myzus persicae
*S. tora*	Aphis craccivora, gossypii; Brachycaudus helichrysi; Macrosiphum euphorbiae
Use key to polyphagous aphids.