R IV+V similar in length
to the black, bluntly triangular cauda. Dorsum with extensive dark sclerotic
areas. ANT III and IV, or III-V, with secondary rhinaria. Longest hairs on
ANT III 1.0-1.5 × BD III
SIPH with a subapical ring of hairs. Aptera (where known) with long thin hair-bearing processes on ABD TERG 7 and 8, and alata with processes at least on ABD TERG 8
….2
–
SIPH without hairs. ABD TERG 7 and 8 with or without processes
…..5
2
Apterae and/or alatae with R IV+V 1.20-1.44 × HT II
…..3
–
Alatae (the only morph known in the case of A. scleroticum), but probably applicable also to apterae) with R IV+V 1.05-1.15 × HT II
…..4
3
Apterae with paired processes on ABD TERG 7 (not including apical hairs) c.0.9 × as long as those on ABD TERG 8. Frontal hairs c.34 μm long. Dorsal hairs of embryos c.15 μm long
Apterae with paired processes on ABD TERG 7 0.6-0.78 × as long as those on ABD TERG 8. Frontal hairs not more than c.23 μm long. Dorsal hairs of embryos only 4-6 μm long
Alata withANT V lacking secondary rhinaria. ABD TERG 7 with a pair of short conical marginal processes bearing long hairs, these processes about one third of length of the paired spinal processes on ABD TERG 8, which are about 57 μm long. Sclerite on ABD TERG 7 encompassing bases of marginal processes and joined anteriorly across ABD TERG 7 to the central brown patch on ABD TERG 3-5
Alatae with 1-3 secondary rhinaria on ANT V. ABD TERG 7 without paired processes or long hairs, and spinal processes on ABD TERG 8 are 28-32 μm long. Sclerite on ABD TERG 7 separate from the central brown patch on ABD TERG 3-5
All adult viviparae alate. Cauda knobbed, anal plate bilobed. SIPH as small truncate cones. ANT PT/BASE less than 2
…..6
–
Adult viviparae apterous and alate. Cauda tongue- or finger-shaped, anal plate entire. SIPH tubular. ANT PT/BASE more than 2
…..8
6
ABD TERG2 with a pair of very large black finger-like spinal processes united at base by a large sclerotic cross-bar that extends laterally into pleural regions, and ABD TERG 1 with a pair of similar but smaller processes. ANT PT/BASE c.1.7
ABD TERG 1 and 2 with or without small pale spinal processes. ANT PT/BASE slightly less than 1
…..7
7
ABD TERG 1 and 2, and 7 and 8, bearing small pale conical spinal processes, with traces of such processes also on ABD TERG 3-6. Forewing veins pale. Legs mainly pale. Secondary rhinaria on thickened dark basal two-thirds of ANT III
Abdominal spinal processes not developed; ABD TERG 1 and 2 with dusky slightly raised spinal sclerites with wax pores. Forewing veins narrowly dark-bordered. Legs mainly dark. Rhinaria distributed along entire length of wholly dark ANT III
SIPH pale except at tips, tapering from a broad base, thin on distal part, without any subapical reticulation. Antennal tubercles well developed, smooth, with inner faces divergent in dorsal view. Cauda long and pale
ANT tubercles well developed, with smooth, divergent inner faces. ABD TERG 1 and 7 without marginal tubercles (MTu). ANT III with 1-47 rhinaria
…..4
–
Either ANT tubercles well developed, but with inner faces scabrous or spiculose and parallel or apically convergent, or ANT tubercles weakly developed, and ABD TERG 1 and 7 with MTu. ANT III with 0-2 (-4) rhinaria (but note that specimens running to Aphis craccivora may be one of the undescribed Aphis (Pergandeida) species collected on Daphne in China and Kashmir)
ANT III (of apt.) with 25-47 secondary rhinaria extending over most of its length. ANT PT/BASE 5.3-7.1. R IV+V 0.67-0.80 × HT II. (Al. with 43-55 secondary rhinaria on ANT III)
Cauda helmet-shaped in dorsal view, a little shorter than its basal width, with an angular apex. Spinal tubercles (STu) usually present, at least on head and ABD TERG 8
…..12
–
Cauda tongue-shaped, at least as long as its basal width in dorsal view, with rounded apex. STu absent
…..14
12
Hairs on front of head long and pointed. SIPH 1.6-2.4 × longer than their basal widths
Hairs on front of head short and blunt. SIPH 2.5-3.5 × longer than their basal widths
…..13
13
Posterior hair on hind trochanter0.24-0.56 (rarely more than 0.5) × length of trochantro-femoral suture. Longest hair on ABD TERG 8 is 11-38 μm, rarely longer than 30 μm. ABD TERG 7 often with a pair of marginal tubercles (MTu)
Posterior hair on hind trochanter0.42-1.00 (rarely less than 0.5) × length of trochantro-femoral suture. Longest hair on ABD TERG 8 is 25-80 μm, rarely shorter than 30 μm. ABD TERG 7 rarely with MTu
Appendages longer, SIPH usually 0.1-0.25 × BL and longer than R IV+V. ANT PT 1.7-3.2 × R IV+V. ANT III without rhinaria (except in alatiform or parasitized specimens)
…..17
17
Large marginal tubercles (MTu) present on ABD TERG 2-5 as well as 1 and 7. Longest femoral hairs only about half as long as trochantro-femoral suture
ANT III with 12-65 protruberant rhinaria. SIPH wholly dark or pale basally and dark over at least distal 0.3. Cauda pale or dark
…..6
6
SIPH cylindrical, wholly dark. Longest hair on ANT III 1.07-1.72 × BD III, and longest hair on ABD TERG 3 about 2.4-3.0 × BD III. First tarsal segments with 4-4-4 hairs
SIPH usually somewhat swollen in middle, and pale basally (e.g. Fig.6i). Longest hairs on ANT III and ABD TERG 3 about 0.9-1.0 × BD III. First tarsal segment with 3-3-3 hairs
…..7
7
SIPH 1.1-1.3 × cauda and 0.15-0.19 × BL, and mainly dark except at their bases. Cauda with 6-18 hairs
Dorsum extensively sclerotised and pigmented. Longest hair on ANT III only c. 0.5 × BD III or less. R IV+V 0.9-1.0 × HT II, with 18-20 accessory hairs. SIPH 2.5-3.4 × cauda, which is helmet-shaped, hardly longer than its basal width
Dorsum membranous. Longest hair on ANT III is 0.7-1.0 × BD III. R IV+V 1.05-1.15 × HT II, with 8-10 accessory hairs. SIPH 2.2-2.4 × cauda., which is finger-like, much longer than its basal width
ABD TERG 6-8 with median
rugose conical processes, each bearing a pair of short (c. 20μm)
club-shaped hairs. SIPH distinctly clavate, with diameter of swollen part
c.1.5 × that of stem
ANT tubercles well developed, divergent. ANT PT/BASE more than 5. ANT III with 1-2 (- 4) rhinaria. ABD TERG 1 and 7 without marginal tubercles (MTu)
…..4
–
ANT tubercles weakly developed. ANT PT/BASE less than 5. ANT III without rhinaria. ABD TERG 1 and 7 with MTu
…..8
4
Head densely spiculose ventrally and over inner faces of ANT tubercles. SIPH slightly swollen on distal 0.7 of length, paler at base, about 2 × the dusky/dark triangular cauda (e.g. Fig 26a, b)
…..5
–
Head smooth or with only a few spicules ventrally. SIPH tapering, sometimes with flared apices, usually wholly dark, similar in length to the pale cauda, which is slightly swollen on basal half and acutely pointed at apex (Fig.26e)
…..6
5
Dorsal abdomen with paired dark submarginal intersegmental sclerites (Fig.26a)
Stridulatory apparatus present, consisting of cuticular ridges on abdominal sternites 5 and 6 and a row of peg-like hairs on each hind tibia. Cauda with 10-28 hairs
Cauda 0.08-0.135 × BL (only more than 0.12 × BL in very small specimens with BL less than 1 mm), and 0.8-1.25 × ANT V; pale to dusky, without a constriction, less than 3 × longer than its width at midlength, and bearing 4-7 (usually 5-6) hairs
Cauda 0.12-0.175 × BL, and 1.05-1.7 × ANT V; very pale, usually with a slight mid-way constriction, more than 3 × longer than its narrowest width at midlength, and bearing 5-10 (usually 7-9) hairs
(Apterae of Macromyzus woodwardiae, Nippodysaphis deutziae, Rhopalosiphoninus celtifoliae and Rh. deutzifoliae on Deutzia in spring are all fundatrices, all their progeny being emigrant alatae.)
1
Dorsal body hairs at apices of long tapering processes that are up to 0.54 mm long (Fig.32b). (BL c. 3.1-3.2 mm)
SIPH tapering, cylindrical, or moderately swollen with diameter of swollen part less than 2 × minimum diameter of basal part
…..3
3
SIPH pale, with a subapical zone of polygonal reticulation. Head smooth, without spicules, and with well-developed ANT tubercles. ANT III with 1-10 rhinaria, and longest hairs 0.7-1.0 × BD III
SIPH pale or dark, without subapical polygonal reticulation. If ANT tubercles are well developed then at least ventral side of head is spiculose. ANT III with 0-3 rhinaria; if with any rhinaria then hairs are all shorter than 0.5 × BD III
…..4
4
Head nodulose or spiculose on at least the ventral side. ANT tubercles well developed
…..5
–
Head smooth or somewhat wrinkled, without spicules or nodules. ANT tubercles weakly developed
…..10
5
R IV+V 1.4-1.6 × HT II, and bearing 7-8 accessory hairs
R IV+V 0.9-1.3 × HT II, and bearing 2-7 accessory hairs
…..6
6
SIPH strongly swollen near midlength where they are maximally c.1.5 × minimum diameter nearer base, and c.3 × width of flange; pale for most of length but dusky near tips (Fig.32c). Legs mainly pale
SIPH tapering or somewhat swollen; if swollen then either legs are mainly dark, or swelling is greatest on distal 0.7, and is no more than 1.25 × minimum diameter of basal part and little more than width of flange
…..7
7
Femora dark over at least half of length (ANT and legs usually mainly dark). SIPH somewhat swollen, pale or dark
…..8
–
ANT and legs mainly pale. SIPH tapering or slightly swollen, pale
…..9
8
SIPH wholly dark. Cauda triangular, only a little longer than its basal width. ANT III without rhinaria
Cauda triangular or helmet-shaped, shorter than its basal width.SIPH cylindrical over most of length or slightly swollen on distal part with a subapical constriction and a well-developed flange (Fig.32d). ABD TERG 1 and 7 without marginal tubercles (MTu)
Cauda longer than its basal width. SIPH tapering, without a subapical constriction. ABD TERG 1 and 7 with MTu
…..11
11
SIPH about 2 × cauda which is dark, has a midway constriction and bears c.10 hairs. Al. with secondary rhinaria distributed ANT III 8-10, IV 5-6, V 0-1
ANT PT/BASE more than 1. Eyes multifaceted. Tubular SIPH present
…..2
2
SIPH pale with subapical polygonal reticulation (at least 4-5 rows of closed cells). ANT tubercles with inner faces smooth and divergent. ANT III with 1-13 rhinaria, and with longest hairs 0.6-1.2 × BD III
…..3
–
SIPH pale or dark, without polygonal reticulation. ANT tubercles if well-developed then with inner faces spiculose and steep-sided (parallel or apically convergent). ANT III with 0-3 rhinaria, if with any then longest hairs less than 0.5 × BD III
…..4
3
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
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
Head not spiculose, with ANT tubercles undeveloped or weakly developed, or with median tubercle similarly developed, so that ANT tubercles do not project much beyond middle of front of head in dorsal view
…..5
–
Head spiculose, with well-developed, steep-sided ANT tubercles
…..13
5
ANT 5-segmented, bearing long hairs up to 4-5 × BD III
Cauda helmet-shaped. SIPH short, pale, conical, almost smooth, with a subapical annular incision below the flange. Spiracular apertures large and rounded
Cauda triangular or tongue-shaped. SIPH pale or dark, imbricated, with or without some subapical transverse striae, but without a distinct subapical incision. Spiracular apertures reniform
…..7
7
ABD TERG 1 and 7 without marginal tubercles (MTu). SIPH subcylindrical or slightly swollen. Anterior part of mesosternum with a pair of closely-spaced, rough-surfaced mammariform processes (sometimes inconspicuous)
…..8
–
ABD TERG 1 and 7 with MTu. SIPH tapering from base to flange, with no trace of swelling. Mesosternum without mammariform processes
……11
8
Cauda about as long as its basal width or shorter. SIPH not longer than 0.21 mm and no more than 0.6 × ANT III. Mesosternal processes small and pale, sometimes inconspicuous. Abdomen without dorsal pigmentation
Cauda longer than its basal width. SIPH longer than 0.26 mm and more than 0.60 × ANT III. Mesosternal processes pale or pigmented, always conspicuous. Abdomen pale or variably pigmented
……9
9
SIPH pale and 0.65-0.95 × ANT III. R IV+V 0.78-0.92 × HT II. Abdomen with little or no dorsal pigmentation
SIPH dusky to dark and 1.0-1.2 × ANT III. R IV+V 0.94-1.25 × HT II. Abdomen with a variably developed dorsal black patch, sometimes fragmented or (often in small specimens) absent
…..10
10
SIPH distinctly swollen distally. Longest hairs on ANT III and ABD TERG II–IV are 6–9 μm, 0.24–0.38 × BD III
SIPH strongly swollen on distal 0.7, with maximum diameter of swelling 1.7-2.9 × minimum diameter nearer base. SIPH about as long as or longer than head width across eyes and 2.2-3.2 × cauda which bears only 5 hairs. ANT III usually with 1-4 rhinaria near base
SIPH tapering, cylindrical or with slight, moderate or strong swelling distally, but if strongly swollen then SIPH are relatively shorter, and if swollen at all then ANT III is without rhinaria
…..14
14
SIPH tapering gradually from base to flange. ANT III with 1-2 small rhinaria near base
SIPH slightly to moderately swollen distally. ANT III without rhinaria
…..15
15
SIPH 0.54-0.81 × ANT III
…..16
–
SIPH 0.82-1.34 × ANT III
…..18
16
Inner faces of ANT tubercles approximately parallel in dorsal view. “Stem” of SIPH narrow, its minimum diameter slightly less than diameter of hind tibia at its midpoint
Inner faces of ANT tubercles with convergent apices. “Stem” of SIPH thicker, its minimum diameter exceeding diameter of hind tibia at its midpoint
…..17
17
SIPH with swollen part only lightly imbricated and with apical flange well developed. Dorsal cuticle not rugose. (Al. with dark-bordered wing veins, and with a black central dorsal abdominal patch)
SIPH with swollen part scabrous (coarsely imbricated), and with apical flange only weakly developed. Dorsal cuticle very rugose. (Al. with wing veins not black-bordered, and with separate transverse bars on abdominal tergites)
R IV+V in most specimens with only one pair of lateral accessory hairs (plus 0-3 ventral accessory hairs). Value of function CAUDA/(ANT III × PT) in range 0.80-1.52, but rarely more than 1.25 except in small specimens (those with ANT III less than 0.32 mm)
R IV+V in most specimens with two pairs of lateral accessory hairs. Value of function CAUDA/(ANT III × PT) in range 1.2-2.7 (rarely less than 1.25)
…..19
19
ANT PT/BASE 2.1-3.7 (mostly less than 3.25). R IV+V 0.87-1.28 × HT II (rarely less than 0.9 × HT II), or value of function (306 × R IV+V) minus (127 × HT II) is more than 17
ANT PT/BASE 2.5-4.0 (mostly more than 3.25). R IV+V 0.78-0.98 × HT II (rarely more than 0.9 × HT II), or value of function (306 × R IV+V) minus (127 × HT II) is less than 17
SIPH cylindrical or tapering, if at all swollen on distal half then longer relative to ANT III, stem thicker, and swollen part imbricated
…..3
3
Inner faces of ANT tubercles smooth and divergent. SIPH with a subapical zone of polygonal reticulation (at least 4-5 rows of closed cells). Hairs on ANT III 0.6-1.0 × BD III
…..4
–
Inner faces of ANT tubercles spiculose or scabrous, and steep-sided. SIPH with subapical transverse striae, but without polygonal reticulation. Hairs on ANT III less than 0.5 × BD III
…..5
4
R IV+V 0.6-0.8 × HT II. ABD TERG 2-4 often bearing marginal tubercles (MTu) that are as large as or larger than the spiracular apertures
Dorsum with paired dark pleural and marginal (or fused pleuromarginal) sclerites. SIPH as thick as or thicker than cauda, which bears 5 hairs. R IV+V 0.6-0.9 × HT II. ANT tubercles rather low, scabrous
SIPH pale on basal half and dark on distal half, and usually slightly swollen subapically. SIPH and femora covered with irregular, transverse rows of spicules. (Al. with dark-bordered wing veins, with radius and costa fused for part of lengths to form a closed cell behind the pterostigma
SIPH either mainly pale or mainly dark; tapering, cylindrical, or clavate. SIPH and femora smooth or imbricated, not markedly spiculose. (Al. with normal wing venation, veins not dark-bordered)
…..2
2
ANT 5-segmented, with hairs up to 4-5 × BD III.ANT PT/BASE 4.5-5.9, with PT usually curved
ANT usually 6-segmented, if 5-segmented then with much shorter hairs and with ANT PT/BASE less than 4
…..3
3
SIPH, cauda and legs all dark. SIPH somewhat swollen on distal half. R IV+V 1.2-1.8 × ANT BASE VI. Dorsum with a pattern of spinules arranged in polygons, with 1 or more spinules in the centre of each polygon
Cauda pale, ANT and legs at least partially pale, SIPH pale or dark. SIPH cylindrical, tapering or clavate. R IV+V 0.6-1.3 × ANT BASE VI. Dorsum without a pattern of spinules arranged in polygons
SIPH pale on basal half and dark on distal half, and usually slightly swollen subapically. SIPH and femora covered with irregular, transverse rows of spicules. (Al. with dark-bordered wing veins, with radius and costa fused for part of lengths to form a closed cell behind the pterostigma
SIPH either mainly pale or mainly dark; tapering, cylindrical, or clavate. SIPH and femora smooth or imbricated, not markedly spiculose. (Al. with normal wing venation, veins not dark-bordered)
…..2
2
ANT 5-segmented, with hairs up to 4-5 × BD III.ANT PT/BASE 4.5-5.9, with PT usually curved
ANT usually 6-segmented, if 5-segmented then with much shorter hairs and with ANT PT/BASE less than 4
…..3
3
SIPH, cauda and legs all dark. SIPH somewhat swollen on distal half. R IV+V 1.2-1.8 × ANT BASE VI. Dorsum with a pattern of spinules arranged in polygons, with 1 or more spinules in the centre of each polygon
Cauda pale, ANT and legs at least partially pale, SIPH pale or dark. SIPH cylindrical, tapering or clavate. R IV+V 0.6-1.3 × ANT BASE VI. Dorsum without a pattern of spinules arranged in polygons
SIPH dark on distal part, paler towards bases, with a subapical zone of polygonal reticulation. Femora with distal 0.2 of length black. R IV+V 0.65-0.8 × ANT VI BASE
SIPH pale or only dark at apices, with or without subapical polygonal reticulation; if with, then femora without black apices and R IV+V 0.8-1.1 × ANT VI BASE
More than 250 aphid species feed on grasses. Some are found only on grasses living in certain habitats, but very few are specific to a particular grass genus or species. The key is subdivided to make it less cumbersome; the main key enables direct identification of individual species and those in small genera, and also leads to a series of subsidiary keys separating species with particular morphological features. Aphids on Miscanthus are treated in a separate key, as there are nine Melanaphis spp. that appear to be specific to that genus.
Numerous other aphid species are found on bamboos, and are treated under the genus names Bambusa and Arundinaria. For simplified, illustrated keys to the aphids most commonly found on cereal crops, and on the grasses of temperate and tropical pastures, consult Blackman & Eastop (2000).
Main key to apterae of grass-feeding aphids
1
ANT PT/BASE more than 0.4 (but if less than 0.65 then body markedly elongate)
…..2
–
ANT PT/BASE 0.2-0.5. Body globose, broadly oval or spindle-shaped
…..30
2
ABD TERG 8 with a pair of very large, densely nodulose, backwardly-directed conical processes, and with or without similar but thinner spinal and marginal processes on other tergites
…..3
–
ABD TERG 8 without large paired conical processes (sometimes with a median process)
…..6
3
Conical processes only on ABD TERG 8. SIPH with swollen part bent towards midline, nearly at a right angle to the pedunculate basal part
A greater number of conical processes present, both spinal and marginal. SIPH straight
…..4
4
Spinal processes present on all segments from head to ABD TERG 8, and marginal processes on meso- and metathorax, ABD TERG 1-4 and 6-7 (40-42 in total)
Cauda either very broadly rounded (less than 0.5 × longer than its basal width) or with a conical base and a midway constriction delimiting the apical part as a rounded knob. SIPH either stump-shaped, conical or poriform. ANT 4- or 5-segmented, often very short. Dorsal cuticle often sclerotic, and dorsal hairs usually thick and spine-like or with expanded apices
Cauda triangular, helmet-shaped, lanceolate, tongue- or finger-shaped, much more than 0.5 × its basal width, sometimes with a midway constriction but the apical part is not a rounded knob. SIPH tubular, flask-shaped, conical, mammariform or poriform. ANT 5- or 6-segmented, short or long. Dorsal cuticle with or without sclerotisation, dorsal hairs not thick and spine-like; blunt or pointed, or with expanded apices
…..7
7
SIPH mammariform, or poriform, or as very short tubes or broad-based cones, as short as or shorter than their basal widths and usually less than 0.35 × cauda
SIPH tubular; flask-shaped, conical, cylindrical or swollen, long or short but if less than 0.4 × cauda, then longer than their basal widths
…..8
8
SIPH with a subapical zone of reticulation, comprising one or more complete rows (rings) of clearly-defined closed cells (if with only 1-3 rows then tergum sclerotic)
SIPH without any clearly-defined subapical reticulation; in some species there is some ill-defined subapical reticulation that may include 1-3 rows of almost complete cells, or interconnected transverse striae, in which cases the tergum is not sclerotic
…..9
9
ANT 5-segmented with PT/BASE less than 2. SIPH slightly to distinctly clavate
…..10
–
ANT 5- or 6-segmented, but if 5-segmented then PT/BASE is rarely less than 2. SIPH tapering, cylindrical or clavate
…..13
10
Body markedly elongate. Front of head between ANT bases markedly convex. Dorsum with polygonal glandular facets on pigmented sclerites. ANT PT/BASE 0.6-0.8
Body oval. Front of head sinuate in dorsal view, with ANT tubercles and median frontal tubercle weakly to moderately developed. Dorsal sclerites pale and without any distinct glandular facets. ANT PT/BASE 0.7-1.9
…..11
11
ANT III 1.25-1.60 × ANT IV. R IV+V 0.6-0.8 × HT II, and without accessory hairs. Cauda tapering, c.2 × its basal width in dorsal view
ANT III 1.8-2.6 × ANT IV. R IV+V 0.8-1.2 × HT II, and bearing (1-) 2-6 accessory hairs. Cauda thick, parallel-sided basally and convex-sided distally, about 1.5 × its basal width in dorsal view
…..12
12
ANT PT/BASE 1.5-1.9. R IV+V less than 1.5 × its basal width, 0.5-0.8 × ANT PT. SIPH markedly clavate, with maximum width of swollen part c. 2 × width at flange
ANT PT/BASE 0.69-1.48. R IV+V 1.9-2.5 × its basal width, 1.0-1.33 × ANT PT. SIPH less strongly clavate, maximum width of swelling less than 1.5 × width at flange
SIPH clavate, i.e. with swollen distal part and narrower basal part
…..17
–
SIPH tapering or cylindrical, or somewhat swollen proximal to a subapical constriction, but without any narrowing of basal part
…..25
17
ABD TERG 8 with a bluntly conical very rugose medial process (Fig.35b). ANT PT/BASE 0.7-1.3. SIPH flangeless, rounded at apex, with a small terminal aperture (Fig.35a). Dorsal cuticle very rugose
Dorsal cuticle without spicules, smooth or wrinkled. R IV+V 0.6-1.0 × HT II
…..19
19
SIPH smooth and swollen on distal half to 1.5-1.9 × their minimum width basad. R IV+V 0.6-0.7 × HT II. Head with smooth divergent ANT tubercles. (Al. with sec. rhin. distributed III 35-65, IV 16-28, V 0-5)
SIPH swollen to 1.2-1.6 × their minimum width basad (if swollen to more than 1.4 × minimum width then R IV+V 0.8-1.0 × HT II). ANT tubercles variably developed, smooth or somewhat scabrous. (Al. with sec. rhin. distributed III 4-29, IV 0-5, V 0)
…..20
20
ANT III usually with 1-3 rhinaria on slight swelling near base. Head usually with some spicules posterioventrally. ANT tubercles rather well developed, steep-sided, somewhat scabrous
…..21
–
ANT III without rhinaria. Head without spicules. ANT tubercles variably developed
…..22
21
ANT PT/BASE 3.1-3.5. R IV+V.0.67-0.70 × HT II. Tergum coarsely corrugated. (Al. with sec. rhin. distributed III 4-9, V 0-1)
ANT tubercles rather well developed, projecting beyond middle of front of head in dorsal view. ANT PT/BASE 5.0-7.5 (Al. with 8-27 sec. rhin. on ANT III)
ANT tubercles very weakly developed, not projecting beyond middle of front of head in dorsal view. ANT PT/BASE 0.9-5.0 (Al. with 4-12 sec. rhin. on ANT III)
…..23
23
ANT 1.1-1.3 × BL. SIPH 0.26-0.29 × BL. ANT PT/BASE 4-5. RV+V heart-shaped
Cauda helmet-shaped, somewhat constricted at base, not longer than its basal width, with 4-6 hairs. SIPH short, pale, smooth, conical, with an annular incision proximal to the well-developed flange. Spiracular apertures rounded or faintly reniform. ANT tubercles undeveloped
…..26
–
Cauda tongue-or finger-shaped or bluntly triangular, with 4-24 hairs. SIPH various, usually imbricated. Spiracular apertures not large and rounded. ANT tubercles variably developed
…..27
26
ANT 0.7-0.9 × BL, with PT/BASE 4.6-8.1. SIPH long and dark, 0.23-0.29 × BL and 5.9-8.1 × cauda
ANT III without rhinaria. SIPH (at least distally) and cauda dusky/dark. SIPH not broad-based. Cauda with 5-6 hairs. ABD TERG 1 and 7 always with (small) MTu
ANT tubercles moderately to well developed, with inner faces divergent; sometimes low, but always better developed than (more than twice as high as) middle part of front of head or median frontal tubercle, so that there is a frontal sinus. SIPH uniformly pale or dusky or becoming darker towards apices cauda pale/dusky. ABD TERG 1 and 7 without marginal tubercles (MTu)
ANT tubercles weakly developed or, if rather well developed then widely separated and with middle part of front of head convex, or with median frontal tubercle projecting to a similar extent. SIPH sometimes pale but more often entirely dark or with dark apices, cauda pale or dark. ABD TERG 1 and 7 almost always with MTu (in some species these are very small, and they are absent in 2 spp.)
…..go toKEY F (mostly Melanaphis, Rhopalosiphum and Schizaphis spp.)
30
Front of head with a pair of short conical horns between antennal bases. Head and prothorax fused
…..31
–
Front of head without horns. Head and prothorax not fused
…..39
31
Sclerotised areas of cuticle warty, with especially warty areas at posterior margin of prothorax. SIPH pores slightly raised on dusky or dark-pigmented cones, with a few surrounding hairs
…..32
–
Sclerotised areas of cuticle smooth or wrinkled, not warty. SIPH pores not placed on raised cones and without any surrounding hairs
…..33
32
Body oval. Horns broadly rounded at apices. Spinal and marginal wax glands often present on all or most tergites
Meso- and metathorax and ABD TERG 1-6 with paired or single groups of spinalwax glands as well as marginal ones
…..34
–
Thorax andABD TERG 1-6 without spinal wax glands, only marginal ones
…..35
34
Wax glands on at least ABD TERG 5 and 6 fused across midline, forming transverse bands consisting of 22-24 rounded cells. Dorsal cephalic hairs maximally 2-3 × ANT BD III, and longest hair on ANT III about equal to BD III
Wax glands on ABD TERG 5 and 6 with paired separate pleurospinal wax glands as on ABD TERG 1-4, each with 6-8 cells. Dorsal cephalic hairs 0.8-1.4 × ANT BD III, and longest hair on ANT III 1.5-2.1 × BD III
ANT 4-segmented (but this based on only 3 specimens) with distinctly spinulose imbrication extending over whole of ANT III and IV. ABD TERG 8 with a group of c.12 wax glands
ANT 4- or 5-segmented, with ANT III very weakly imbricated and with at most a few minute spinules on the imbrication of distal part of ANT III (if 4-segmented) or on IV (if 5-segmented). ABD TERG 8 with a group of 5-40 wax glands
…..36
36
ABD TERG 1-3 each with 8-19 spinopleural hairs. ANT entirely dusky/dark
ABD TERG 1-3 each with 3-8 spinopleural hairs. ANT pale, or dark only distally
…..37
37
Head with longest anterior dorsal hairs 55-81 μm long, usually as long as or longer than frontal horns which are 48-68 μm long. ABD TERG 8 with a group of 5-20 wax glands. Each lobe of anal plate with 6-8 (-9) hairs
Head with longest anterior dorsal hairs 46-71 μm long, often shorter than frontal horns which are 55-136 μm long. ABD TERG 8 with a group of 15-40 wax glands. Each lobe of anal plate with (8-) 9-12 hairs
…..38
38
Frontal horns symmetrical, straight-sided, 55-100 μm long, broad-based, 1.5-2.2 × their basal widths. First instars with siphuncular pores
Frontal horns with apices somewhat curved distally, 96-140 μm long, slightly constricted at base and 2.5-3.5 × their basal widths. First instars without siphuncular pores
Dorsal cuticle with a densely denticulate ornamentation
…..4
4
Dorsal cuticle with small pointed denticles between bases of long spine-like hairs, which on ABD TERG 3 are more than 45 μm long. Hairs on ANT III usually longer than (0.6-1.8 ×) BD III
Dorsal cuticle with very dense, blunt denticles, and hairs on ABD TERG 3 less than 40 μm long. Hairs on ANT III usually shorter than (0.4-1.0 ×) BD III
SIPH pores of diameter less than midlength diameter of hind tibia, and placed on ABD TERG 5
…..13
13
Dorsal hairs very short, rod- or club-shaped, mostly less than 0.5 × ANT BASE V (or IV). Long pointed hairs only present on front of head and posterior abdomen
…..14
–
Dorsal hairs of various lengths, the longest with pointed apices and as long as or longer than ANT BASE V (or IV), the shorter hairs with pointed, blunt, furcate or serrate apices
…..16
14
ANT 5-segmented, 0.20-0.27 × BL, with PT/BASE 0.75-1.3. Mid-dorsal hairs are mostly rod-shaped, with serrate apices
…..15
–
ANT usually 4-segmented, 0.14-0.17 × BL, with PT/BASE c.0.5. Mid-dorsal hairs flabellate or club-shaped, with rounded or serrate apices
Marginal hairs on ABD TERG 1-6 mostly much shorter than midlength width of hind femur, with serrate apices like mid-dorsal hairs. Empodial hairs spatulate, flat, broadened at apices
Many of marginal hairson ABD TERG 1-6 longer than midlength width of hind femur, with pointed apices. Empodial hairs strap-shaped (base and apex of similar width), not spatulate
Tergum pale or dark, but not black. Some or all of shorter dorsal hairs with blunt or expanded apices. ANT 0.20-0.23 × BL
…..17
17
ABD TERG 8 with 14-18 long, mostly pointed hairs on posterior and lateral margins, and 12-24 shorter hairs more anteriorly with pointed, bifurcate or expanded apices
ANT 0.25-0.35 × BL. Cauda elongate triangular or tongue-shaped, distinctly longer than its basal width, without narrower apical part, bearing 6-9 hairs. ANT 5- or 6-segmented
Tibial hairs long and finely pointed, the longest more than 1.5 × width of tibia at midlength. ABD TERG 1 and 7, or 1-4 and 7, with marginal tubercles (MTu)
…..8
–
Tibial hairs short, not longer than width of tibia at midlength. ABD TERG 1 and 7 without MTu
Cauda long, black and finger-like with a midway constriction, and bearing 12-19 hairs. SIPH as short black broad-based cones, with a distinct apical rim around a large terminal pore
Process on ABD TERG 8 finger-like; sometimes broader at base, but with distal part almost parallel-sided. ANT PT/BASE 1.2-1.65 (except down to 1.0 in summer dwarfs)
KEY C – Apterae with reticulate SIPH on grasses (mainly Sitobion)
This key includes 20 Sitobion spp., 3 Pseudaphis spp., Micromyzodium spinulosum, Macrosiphum euphorbiae and Rhopalosiphoninus indicus, but excludes the species of Sitobion subgenus Metobion, which are included with Metopolophium in KEY D. S. rosaeiformis could not be included because apterae from grasses have not been described.
1
SIPH flask-shaped, dark, 3.2-4.0 × cauda, with the inflated part maximally 2.8-4.8 × wider than the stem
SIPH 0.80-1.00 × cauda, and 1.26-1.71 × R IV+V, which bears 4-6 accessory hairs
…..4
4
BL 1.06-1.55 mm, and SIPH 0.12-0.15 mm. ABD TERG 1-4 with paired dark patches and ABD TERG 5-8 with short dark bars, usually not extending laterally to link with the marginal sclerites
BL 1.70-2.20 mm, SIPH 0.17-0.21 mm. ABD TERG 1-8 usually with broad dark cross-bands extending laterally to include marginal sclerites, often narrowly separated in midline on ABD TERG 1-4
Dorsal cuticle without spicules, and proximal parts of SIPH normally imbricated (often with spinules on the imbrication)
…..7
7
SIPH 0.12-0.17 × BL. ANT PT/BASE 3.0-4.3. Abdomen with a rather solid dusky/dark patch extending across ABD TERG 1-6 and linked with or including marginal sclerites
SIPH 0.18-0.35 × BL. ANT PT/BASE 2.5-9.2. Abdomen with or without dark sclerotisation but this is either ill-defined or segmentally divided or not linked with marginal sclerites
…..8
8
Cauda dark, almost as dark as the brown-black SIPH
ANT tubercles rather weakly developed, and median frontal tubercle often evident. Longest hairs on ANT III 0.3-0.8 × BD III. ABD TERG 8 with 3-6 (usually 4) hairs
…..13
13
R IV+V with 2-4, or rarely 5, accessory hairs. SIPH commonly with basal part pale
…..14
–
R IV+V with 6, rarely 5 or 7, accessory hairs. SIPH mostly uniformly dark, sometimes paler basally
…..17
14
BL 3.7-4.3 mm. Cauda with 10-12 rather short hairs. ANT III with 3-9 rhinaria
Cauda wth all hairs pointed, the more distal ones only a little shorter than those more basal. Hairs on ABD TERG 8 are 20-43 μm long. SIPH mainly pale, darker towards apex
…..16
16
SIPH 1.75-2.0 × cauda, which has a rounded apex. ABD TERG 2-5 usually without marginal tubercles (MTu)
SIPH with subapical reticulation extending for 0.15-0.35 of length
…..19
19
R IV+V 0.80-0.95 × HT II. SIPH usually paler towards base, reticulated on distal 0.15-0.17 of length. Hairs on ABD TERG 8 are 40-55 μm long. ABD TERG 1-4 with variably-developed paired dusky/dark patches
R IV+V 0.65-0.82 × HT II. SIPH uniformly dark and reticulated on distal 0.19-0.35 of length. Hairs on ABD TERG 8 are 25-42 μm long. Dorsal abdomen pale or dusky, without paired dusky/dark patches
SIPH 1.4-1.9 × cauda and 0.75-1.05 × ANT III (measure several specimens if borderline)
…..21
21
SIPH reticulated over distal 0.15-0.40 of length. Longest hairs on ANT III 0.45-0.8 × BD III. Dorsal abdomen sclerotic but with any pigmentation rather ill defined. ABD TERG 2-5 with 0-8 marginal tubercles (MTu) in total, but mostly (67%) with 2-6
SIPH reticulated over 0.10-0.18 of length. Longest hairs on ANT III 0.25-0.6 × BD III. Dorsal abdomen often with variably-developed pattern of clearly delimited dark sclerites, as segmentally-divided transverse bands or an irregular central patch. MTu either absent, mostly confined to ABD TERG 5, or more numerous (totalling 5-8)
…..22
22
Longest hairs on ANT III 8-20 μm, longest posterior dorsal cephalic hairs 8-30 μm, longest hairs on ABD TERG 8 17-45 μm. Dorsal abdomen with variably-developed dark dorsal cross-bands not fused across tergites. ABD TERG 2-5 with only 0-3 MTu in total, mostly absent, or present only on ABD TERG 5
Longest hairs on ANT III 16-23 μm, longest posterior dorsal cephalic hairs 26-32 μm, longest hairs on ABD TERG 8 40-50 μm. Dorsal abdomen with a variably-developed dark central patch not or only partially divided between tergites. ABD TERG 2-5 with 5-8 MTu in total
Longest hairs on ANT III more than 0.6 × BD III. Primary rhinarium on ANT V large, occupying almost entire width of segment. ANT III with 5-8 rhinaria. SIPH black. Tergum usually extensively pigmented, with pigmentation often encompassing marginal sclerites
Longest hairs on ANT III
0.2-0.5 × BD III. Primary rhinarium on ANT V small, occupying less than half
width of segment. ANT III with 0-7 rhinaria. SIPH pale or dark, if black then
tergum not so extensively pigmented
…..24
24
SIPH
pale except towards apices. ANT III-V mainly pale with dark
articulations.
KEY D – Apterae of grass-feeding aphids with spinulose heads
This key includes all the grass-feeding aphids with spinulose heads, except those with reticulate SIPH that were taken out in KEY C (Pseudaphis spp., Micromyzodium spinulosum and Rhopalosiphoninus indicus). Among these are five very polyphagous species (Aulacorthum solani, Myzus ascalonicus, M. ornatus, M. persicae and Neomyzus circumflexus) that are occasionally found on grasses.
1
Head extended forward between ANT bases with three large separate processes, each bearing spine-like hairs. SIPH very large, thick and warty, constricted subapically. ANT PT/BASE 1.37-1.80
ANT normally 6-segmented, sometimes 5-segmented. R IV+V 1.1-1.3 × HT II (Note: Apterae with 5-segmented ANT and R IV+V 1.2-1.5 × HT II may be one of two other Hallaphis spp. only known from trapped alatae.)
R IV+V 1.2-1.7 × HT II. ANT III usually with 1-2 rhinaria near base. Dorsal abdomen with a dark roughly U-shaped patch, pale medially on ABD TERG 1-2(-3)
SIPH with a distinct flange; cylindrical, tapering or clavate
…..8
8
Dorsal surface of head smooth, black, with a pair of spinal tubercles (STu). Cauda long and dark with 3-5 short curved hairs. R IV+V without accessory hairs. (Al. with forewings usually lacking radius)
Dorsal surface of head smooth or spiculose, pale or dark, without STu. Cauda pale or dark, if dark then short and triangular, with 4-11 hairs. R IV+V with 2 or more accessory hairs. (Al. with radius in forewing)
…..9
9
SIPH grossly inflated over distal 0.7, with maximum width of swollen part more than 2 × minimum width of stem and c.3 × width of constricted subapical part, which has a rather indistinct reticulate pattern
SIPH tapering, cylindrical or slightly to moderately swollen, with swollen part less than 2 × minimum width basad or distad
…..10
10
Femora spinulose over entire length . SIPH very slightly swollen subapically. Cauda swollen at base, with a constriction of distal half, and bearing 4 hairs. (Al. with broadly dark-banded forewing veins and media fused with radius)
Femora not spinulose, or with spinules only on distal half. SIPH tapering/cylindrical or swollen over greater part of length. Cauda triangular or tongue-shaped, unconstricted, with 4-8 hairs. (Al. with normal wing venation)
…..11
11
SIPH tapering, with a slight S-curve, coarsely imbricated. Dorsal abdomen with a pattern of dark intersegmental markings. ANT PT/BASE 1.7-2.8
SIPH tapering/cylindrical or swollen, not coarsely imbricated. Dorsal abdomen without dark intersegmental markings. ANT PT/BASE 2.8-5.5
…..12
12
Dorsal hairs with expanded apices, short or long. SIPH dusky/dark, swollen over most of length, without a narrow section on basal half. Cauda short, triangular, not longer than its basal width. ANT and legs mainly dark
…..13
–
Dorsal hairs very short and blunt. SIPH pale or dark, cylindrical/tapering, or swollen on the distal half with a narrower section on the basal half. Cauda much longer than its basal width. ANT and legs pale or at least not mainly dark
…..14
13
Dorsal hairs 40-65 μm long. Longest hairs on ANT III 0.6-1.0 × BD III
Head smooth dorsally and anterioventrally, with a few rows of spicules posterioventrally.R IV+V short and blunt, 0.8-0.9 × HT II. ANT III usually with 1-3 rhinaria on slight swelling near base. SIPH swollen over distal 0.7 of length
ANT III with 0-2 rhinaria near base. SIPH 2.1-2.7 × cauda. R UV+V longer than its basal width, 0.75-0.95 × HT II. Tergum sclerotic and usually dark-pigmented, at least marginally
ANT III with 8-17 rhinaria distributed over 0.5-0.7 of length. SIPH 1.3-1.6 × cauda. R IV+V shorter than its basal width, 0.6-0.7 × HT II. Tergum pale not or hardly sclerotic
SIPH 1.3-2.5 × cauda, but if less than 1.4 × cauda then either R IV+V is 0.6-0.7 × HT II (which is 0.128-0.183 mm long), or hind tibia is more than 0.9 mm long
…..12
12
R IV+V 0.91-1.13 × HT II. ANT PT/BASE 1.8-2.8
…..13
–
R IV+V 0.60-0.98 × HT II; if more than 0.9 × HT II (some festucae)then ANT PT/BASE normally in range 2.9-4.0 (although apterae developing in cold conditions may have ANT PT/BASE as low as 2.1)
…..14
13
SIPH 1.7-2.3 × cauda, and without any subapical reticulation. ANT tubercles well developed
ANT III with 0-4 rhinaria. ANT PT/BASE 2.1-5.0, but if less than 3.0 (cold temperature festucae) then R IV+V more than 0.7 × HT II
…..15
15
SIPH 0.25-0.36 × hind tibia. HT II 0.128-0.183 mm (only less than 0.146 mm if BL is less than 2 mm and ANT PT/BASE 3-4)
…..16
–
SIPH 0.34-0.52 × hind tibia, but if less than 0.36 × then HT II is 0.096-0.146 mm long (only more than 0.128 mm if BL is more than 2 mm and/or ANT PT/BASE less than 3)
…..17
16
SIPH 1.7-2.0 × cauda. ANT PT 3.3-4.4 × HT II. ANT V 1.2-1.7 × cauda. R IV+V 0.65-0.78 × HT II. If still inconclusive, the function (PT × SIPH)/ (cauda × HT II) is in range 6.0-8.6
SIPH 1.3-1.9 × cauda. ANT PT 2.6-4.1 × HT II. ANT V 0.9-1.4 × cauda. R IV+V 0.61-0.72 × HT II. If still inconclusive, the function (PT × SIPH) / (cauda × HT II) is in range 3.6-6.5
Hind tibia 11.3-16.7 × R IV+V (only less than 12 × when BL less than 2.2 mm). ANT BASE VI 1.20-1.62 × HT II (only less than 1.3 × when either BL less than 2 mm or ANT BASE VI is 0.36-0.42 × ANT IV)
Hind tibia 7.1-12.0 × R IV+V (only more than 11.3 × when BL is 2.2-2.7 mm). ANT BASE VI 0.95-1.29 × HT II (only more than 1.2 × when BL more than 2 mm and ANT BASE VI is 0.43-0.53 × ANT IV)
R IV+V 0.092-0.119 mm long, 0.67-0.87 × HT II, and bearing 5-10 accessory hairs. Hind tibia 0.87-1.71 mm long, HT II 0.116-0.164 mm long. ANT PT/BASE 3.0-5.0. If inconclusive then function (A × B × C) / (D × E × F) is 6.5-12.7, where A = length of ANT flagellum (III+IV+V+VI incl. PT), B = length of hind tibia, C = HT II, D = body length (in this case incl. cauda), E = ANT VI BASE, and F = R IV+V
R IV+V 0.089-0.114 mm long, 0.72-1.0 × HT II, and bearing 3-8 accessory hairs. Hind tibia 0.75-1.22 mm long, HT II 0.096-0.133 mm long. ANT PT/BASE 2.1-4.2. If inconclusive then function (A × B × C) / (D × E × F) is 3.9-8.1
KEY F – Mostly Melanaphis, Rhopalosiphum and Schizaphis.
This key includes apterae of the rest of the grass-feeding Aphidinae not covered by KEYS B-E. To qualify for this key your aphid should have (a) 5- or 6-segmented ANT with ANT PT/BASE more than 1, (b) a non-spiculose head with low ANT tubercles, (c) SIPH tubular or conical, 0.45-2.5 × cauda, which is tongue- or finger-shaped, and (d) marginal tubercles on ABD TERG 1 and 7 (with 2 exceptions).
1
SIPH short and usually thick or rather thick, less than (often much less than) 2.4 × their basal width, 0.45-1.2 × cauda, and usually with a well-developed, rather swollen flange
…..2
–
SIPH tapering, cylindrical or slightly swollen, 0.6-2.5 × cauda, but if less than 1.2 × cauda then they are more than 2.4 × their basal width, and/or have a small flange
…..16
2
Hairs on ANT III very long and fine, up to 4-7 × longer than BD III
ABD TERG 1-4 each with 1-2 hairs on each side. ABD TERG 8 with 2 hairs
…..10
10
Longest hairs on ANT III c.1.0 × BDIII. Hind tibia with longest hairs 1.3-2.0 × diameter of tibia at midlength. Marginal hairs on ABD TERG 1-4 27-47 μm
Longest hairs on ANT III 0.3-0.7 × BD III. Hind tibia with longest hairs not more than 1.2 × diameter of tibia at midlength. Marginal hairs on ABD TERG 1-4 14-30 μm
…..11
11
SIPH 0.46-0.68 × cauda
…..12
–
SIPH 0.70-1.05 × cauda
…..13
12
SIPH pale/dusky, at least 1.5 × longer than their basal widths, and 0.46-0.63 × cauda, both pale or dusky. (Sec. rhin. in al. III 19-45, IV 2-21, V 0-11)
Tergum of thorax and abdomen with a reticulate pattern of strings of small bead-like spicules arranged in polygons, most polygons enclosing one to many additional similar spicules. SIPH in all except one species almost cylindrical for most of length or with very slight swelling of distal part, constricted subapically and then broadened again to a well-developed flange (as if a noose had been placed around near the apex and tightened slightly). (Alata with media of forewing twice-branched)
…..17
–
Tergum smooth, wrinkled or spiculose, but if spiculose then the spicules are coarser and more angular and not arranged as above. SIPH cylindrical or tapering, sometimes with a slight subapical constriction, but usually with a small flange. (Alata with media once- or twice-branched)
…..23
17
Body rather elongate. SIPH 0.07-0.08 × BL, tapering from base with only a slight subapical constriction and small flange. ANT PT/BASE 1.7-2.8
Cauda long and very pale, with only 4 hairs. SIPH slightly swollen on basal half (calf-shaped). ANT PT/BASE 5.0-6.3. (Hind wing of al. with only one oblique vein)
Cauda pale, dusky or dark with 4-28 hairs. SIPH cylindrical or tapering, not at all swollen on basal half. ANT PT/BASE 1.7-6.0. (Hind wing of al. with 2 oblique veins)
…..45
45
SIPH 2.1-3.0 × cauda. ANT entirely dark except for base of III. (Forewing of al. with once-branched media)
KEY G – Apterae of Anoecia and Tetraneura on grasses
Apterae included in this key all have very short ANT PT, SIPH as slightly elevated cones and a broadly rounded cauda. Two Anoecia spp. described from India, A. himalayensis and A. radiciphaga, could not be included on the basis of their published descriptions; a key to Indian Anoecia is provided by Chakrabarti et al. (1982).
1
Tarsi 2-segmented. Eyes usually multifaceted. ANT more than 0.25 × BL. ANT III-V often with secondary rhinaria. Flat rounded marginal tubercles (MTu) are usually present
…..2
–
Tarsi 1-segmented. Eyes usually with just a triommatidium. ANT less than 0.25 × BL. ANT without sec. rhin. Wax glands comprising one to many cells usually present
…..13
2
MTu usually present on all of ABD TERG 1-7; often reduced in size on ABD TERG 5 and 6, and sometimes absent from 6, or occasionally both 5 and 6
…..3
–
MTu on ABD TERG 1-4 and 7, but always absent from 5 and 6
…..6
3
Compound eyes reduced to 0-10 (-25) facets, usually smaller than triommatidia. ANT III–V without sec. rhin. Dorsal abdomen often unsclerotised. BL 1.2-2.1 mm
Compound eyes with more than 25 facets. ANT III-V usually with sec. rhin. Dorsal abdomen usually with extensive dusky/dark sclerotisation. BL 1.9-3.0 mm
…..4
4
ABD TERG 1-5 with short (10-15 μm) blunt or spatulate hairs, which at least on 4 and 5 are placed in single tranverse rows. R IV+V with 5-6 (-8) accessory hairs
ABD TERG 1-4 (-5) each with numerous fine-pointed hairs; spatulate hairs (41-73 μm long) occur only irregularly if at all on ABD TERG 5-7, and only those on 6 and 7 are arranged in transverse rows. R IV+V with 8-14 accessory hairs
…..5
5
Rostrum 0.76-0.96 mm long, reaching well past bases of hind coxae to about middle of abdomen. BL (2.2-) 2.5-3.0 mm. Hairs on ABD TERG 6 and 7 usually all fine-pointed
Rostrum 0.52-0.85 mm long, reaching about to bases of hind coxae. BL 1.9-2.4 (-2.8) mm. One or more of hairs on ABD TERG 6 and 7 almost always spatulate
Dorsal abdomen unsclerotised or only with dusky/dark bands on ABD TERG (5-) 6-7. Compound eyes often reduced to less than 20 facets. ANT III-V without sec. rhin.
…..7
–
Dorsal abdomen extensively sclerotised on ABD TERG 3-7, with either broad dark bands or a solid or perforated dark shield. Compound eyes with more than 25 facets. ANT III-V usually each with 1 or more sec. rhin.
…..9
7
ANT III only c.0.13 mm long, less than 0.09 × BL. (Al. developing on grasses have a large black dorsal abdominal patch over ABD TERG 3-6)
ANT III 0.24-0.38 mm long, longer than ANT IV+V and 1.9-2.5 × R IV+V Most hairs on ANT and legs fine-pointed, with sometimes a few interspersed spatulate hairs
Marginal hairs of adults and embryos long or short but with fine-pointed, acute or blunt apices (or sometimes dilated apically in adults, but not in embryos)
…..15
15
ANT flagellum with less than 8 hairs between apex of II and distal rim of penultimate primary rhinarium
…..16
–
ANT flagellum with more than 8 hairs between apex of II and distal rim of penultimate primary rhinarium
…..17
16
Longest ANT hairs not longer than BD III. Spinal and pleural wax glands on ABD TERG 1-5 each usually comprising a ring of cells (diam. 52-65 μm) around an undivided or partially subdivided central area. ABD TERG 7 with 4-6 hairs. Embryos inside abdomen with hind tarsal claws similar to those of fore and mid tarsi
Longest ANT hairs longer than BD III. Spinal and pleural wax glands on ABD TERG 1-5 small (diam. 12-25 μm), each comprising a single cell or a group of 2-3 contiguous cells. ABD TERG 7 with 8 hairs. Embryos inside abdomen with hind tarsal claws much longer than those of fore and mid tarsi
ANT II with 6-18 hairs. ABD TERG 8 with 6-15 similar-sized hairs. Wax glands each usually comprising a group of cells with one large cell 14-77 μm in diameter, of irregular shape and sometimes appearing partially subdivided, with many small cells alongside or partly surrounding it
ANT II with 2-5 hairs. ABD TERG 8 with 2 thick and spine-like hairs of varying length, often very long, sometimes with additional smaller marginal hairs. Wax glands each usually comprising a small group of mostly similar-sized cells 7-24 μm in diameter, with or without an adjacent cluster of very small cells
…..18
18
ABD TERG 8 commonly with one or more smaller marginal hairs in addition to a pair of very large spinal hairs. Embryos in abdomen (dissect some out when mounting if possible) without spinules on hind tarsi, and with ABD TERG 1-5 each having a transverse row of 6-10 spino-pleural hairs between the 2 larger marginal hairs
ABD TERG 8 usually only with a pair of very large spinal hairs, rarely with 1-2 additional hairs. Embryos in abdomen with minutely spinulose hind tarsi, and with ABD TERG 1-5 each usually having a transverse row of (5-) 6 spino-pleural hairs
Marginal wax glands comprising single cells with surface appearing stippled, maximum diameter 20-40 μm. ABD TERG 8 with 2-8 hairs, including at least 2 long thick spinal hairs
…..23
23
Penultimate ANT segment with 18-30 hairs. Embryos inside abdomen (dissect some out before mounting if possible) with ABD TERG 1-5 each bearing 12-20 pleuro-spinal hairs between marginal groups of 3-8 hairs. Embryos have 16-23 hairs on penultimate ANT segment (IV) and 10-16 accessory hairs on R IV+V
Penultimate ANT segment with 36-60 hairs. Embryos inside abdomen with ABD TERG 1-5 each bearing 20-50 pleuro-spinal hairs between marginal groups of 10-15 hairs. Embryos have 30-55 hairs on penultimate ANT segment (IV) and 18-24 accessory hairs on R IV+V
KEY H – Apterae of Colopha, Fordini and Pemphigini on grassses
1
Tarsi 1-segmented (sometimes with an incomplete suture). Wax glands each comprising a ring of cells around a round or oval, usually darkly-defined and often undivided central area
…..2
–
Tarsi 2-segmented. If wax glands are present then they are comprised of numerous cells (pores) without a darkly-defined central area
…..5
2
Antennae 6-segmented. Eyes with about 10 ommatidia. Wax glands with darkly-defined central areas in first instars, but not in adults
ANT II similar in length to I, much shorter than III
…..7
7
ANT usually 6-segmented. Legs thick, especially hind tibiae which are more than 0.7 of width of hind femora at their respective midpoints. Dorsal cuticle with fine reticulation
…..8
–
ANT 5-segmented. Hind tibiae less than 0.7 of width of hind femora at their respective midpoints. Cuticle not distinctly reticulated
…..9
8
Hairs very short, those on ANT III only 4-12 μm long (based on 4th instar)
Head cuticle rather coarsely spiculose, with angular spicules partially joined to form a reticulum. Marginal hairs on ABD TERG 1-5 are 6-28 μm long with acute, blunt or expanded apices
…..16
16
Tibiae each with a row of short, stout erect peg-like hairs on dorsal side. Hairs on ABD TERG 8 long (more than 50 μm), and in larger specimens often thick and strap-like, with some of them having spatulate or furcate apices
Anal plate enlarged and extended or displaced dorsally, surrounded on three sides by the U-shaped ABD TERG 8 so as to form a trophobiotic organ (e.g. Plate 1h, i)
…..20
–
Anal plate and anus in normal posterio-ventral position
…..27
20
Small faceted wax glands present on head (3 pairs), and spinal as well as marginal pairs of small wax glands present on thorax and abdomen. All body hairs pointed
Wax glands not usually evident, or only marginal glands present.. Dorsal body hairs pointed, spatulate or fan-shaped
…..21
21
Anal plate with scattered, shortish, sometimes spatulate, hairs, not arranged in two longitudinal rows
…..22
–
Anal plate with long and usually pointed hairs arranged in two longitudinal rows (as well as finer, shorter hairs grouped near anus)
…..23
22
R IV+V with 4-14 hairs. ABD TERG 8 with 11-25 hairs, and anal plate with 15-120 hairs. Dorsal hairs as well as those on anal plate very variable, often spatulate or fan-shaped, but not with very finely-attenuated apices
R IV+V with 16-30 hairs. ABD TERG 8 with 50-100 hairs, and anal plate with c.80-200 hairs. Hairs on dorsal body and anal plate rarely spatulate, often with very finely attenuated apices
Longest hairs on ABD TERG 1-3 (unless all spatulate) more than 1.5 × ANT BD III. ANT PT 0.015- 0.04 mm long, ANT PT/BASE 0.15-0.52
…..25
25
Dorsal hairs comprising 1 spinal, 1 pleural and 1-4 marginal pairs per segment. Marginal wax glands usually present on ABD TERG 1-7. R IV+V 1.64-2.10 × HT II. (Al. with secondary rhinaria ciliated)
Dorsal hairs much more numerous, in bands across segments, with marginal groups of 3-10 hairs per segment, of which 1-2 are usually much longer. R IV+V 1.2-1.7 × HT II. (Al. with secondary rhinaria with or without cilia)
…..26
26
Dorsal hairs variable in form, but usually most are spatulate, except for 1-2 long acute marginal ones per segment. R IV+V with 4-8 accessory hairs. ABD TERG 8 with 5-9 hairs. (Al. with secondary rhinaria not ciliated)
Body broadly oval, ANT and tibiae both more than 0.2 × BL
…..29
29
Wax pore plates present on head, thorax and abdomen, especially well developed marginally on abdomen. R IV+V 0.13-0.175 mm long, with 4-8 accessory hairs. Cauda and anal plate forming a dark, rounded posterior projection of the abdomen
Wax pore plates absent form head and typically also from thorax and margins of abdomen; usually with 4 (2 spinal and 2 pleural) on each of ABD TERG 3-6 and 1 spinal pair on ABD TERG 7. R IV+V 0.08-0.12 mm long, with 0(-2) accessory hairs. Cauda and anal plate not produced posteriorly