August 06, 2021

African genera of Gryllacrididae

Translated and forced into shape from Karny's 1937 paper on the (super)family.

This is abbreviated from a much larger key to the world genera, and retains Karny's generic classification, although it is worth noting that at least some authors treat African Niphetogryllacris as belonging to Stictogryllacris (which does have the bonus of not having to dry out a female specimen and see what happens to her ovipositor in order to successfully take members of these genera through this key). In cases where long strings of couplets only included a single Afrotropical terminal, I have condensed the infomation relating to that terminal into the couplet where it diverges from other Afrotropical options, usually contained in parentheses to avoid confusion with characters of the couplet contained; so if, for example, you come across a couplet of this form:

A. Animal with a purple head................................................B

  • Animal with an orange head; (Animal with all four wings exceeding the tip of the abdomen; legs strongly spined).....................................................................................C

If your specimen has a purple head but also four long wings and strongly spined legs, you would still go to B, as the information in parenthesis is not necessarily exclusive to C, and is only retained such that, if you have an animal with an Orange head, smooth legs and short wings, you know that you are in the wrong part of the key (or looking at something new). (This is a fictional couplet and does not appear in the key).

Additionally, my German is not good so in places where I am unsure of the translation of a word, the original may appear in parenthesis following my translation, or if I cannot make sense of a phrase or sentence you may find a bracketed question mark to indicate that the problem may be my translation.

The latter part of the key mostly focuses on a complicated series of couplets all leading to Glomeremus; these have been retained as separate in order to retain such species distinctions as Karny includes, and to avoid removing potentially useful character information.

Finally, this is very much a draft, and certainly includes some redundant character descriptions where some lines have been condensed; I will revisit this and remove, but on the offchance that this draft is useful, I am putting it up so that anyone can make as much as of it as they can.

(From Karny, H.H. (1938). Orthoptera. Fam. Gryllacrididae. Genera Insectorum 206 pp. 1-317)

(All) Hind tibia on both sides similarly spined, in the usual manner, or otherwise without spines.

1A. Wings developed, significantly longer than pronotum..............2
1B. Wings missing or rudimentary; at most, elytra just as long as the pronotum (Upperside of ovipositor not serrated)........….25

2A. Medial (vein) of the elytra free and clearly springing from the base of the wing, although merging with a neighbouring vein at well removed from the base. If the media DOES emerge from the R-veins, then the hind tibia are without spines (Brow weaker and differently (from Australian Pterapotrechus) sculptured, at least without side-folds (Seitenfalte)).................................................3
2B. Medial (vein) of elytra not distinguishable at the base of the wing, only emerging from the Radial or Cubital vein later. Hind tibia always spined..............................23

3A. Meso- and Metasturnum distinctly bilobed, the lobes rather sharp-tipped Hindwing hyaline, never fasciated-hyaline. Rs and M on either side with simple, common root original from the radial stem. Fore-tibiae of male apico-dorsally bilobate, and with a large, claw-shaped, downturned extension….............Afroepacra (E. Africa)
3B. Meso and Metasternum rounded; not or barely lobed..............................4

4A. Radial sector of the hindwing separated from the medial vein, emerging from the radius, but soon aftewards reuniting with the medial vein and forming a cell divided by a few crossveins, or remaining permanently united with it; or touching only at a single point, or touching only for a very short distance.........................................................5
4B. Rs and M in the hindwing with a simple, common root emerging from the radial trunk, only exceptionally separated basally, but not on both hind wings; OR the veins originating very close to one another; OR forming only forming a short longitudinal cell, not interrupted by transverse veins, OR the hind wings rudimentary.................................8

5A. Ovipositor weakly chitinous, the sheath rolling up into a spiral on preserved specimens.....9
5B. Ovipositor strongly chitinous, remaining together in specimens, and not rolling..................6

6A. Elytra long, usually more than twice as long as the hind femur (Underside of hind femur normally spined, not excavated; ovipositor differently formed (to Acanthogryllacris’ distinctly short, sickle-curved and blunt-ended, neither bevelled nor rounded))(Australian spp. and Hadrogryllacris rautheri from (?) Ghana).………....................................7
6B. Elytra shorter, at most between one-and-a-half and twice as long as the hind femur; Medial and cubital veins in the elytra less strongly developed (than Tytthogryllacris), with at most 4 branches altogether; Hind wings hyaline (clear, glassy) or otherwise smoky, without marked bands; Overall colour light-brownish yellow, elytra with similar-coloured veins; male and female genitalia not as in Celebogrylacris (Celebes); The mobile spines of fore and middle tibia of normal length. Stylus present in the male subgenital plate; Elytra only about ¼ longer tan hind legs; hindwings distinctly cycloid (?). On the male cerci on each side an S-shaped curve, the end hook-shaped, bent upwards and inwards, and ending in a thorn-like extension of the tip.......…….....Barombogryllacris (Gabon, Elsewhere?)

7A. Branches of the radial vein of the elytra all, or at least mostly, terminating in the subcosta.....................................Hadrogryllacris (Possibly present in Ghana?)
7B. Branches of the radial vein opening into the anterior margin, only exceptionally the first ending at its meeting with the subcosta; Subgenital plate of the male without styluses; Mostly larger, strongly built species, generally brownish or black. Crossveins, especially on hindwings, usually traced with narrow, dark lines; head often plump, with a wrinkled, spotted frons; top of the head usually with sharp, protruding, linear marginal keels; Male Subgenital plate 2-4 lobed; Subgenital plate clearly 3 or 4 lobed. Ovipositor straight or slightly curved, usually at least twice as long as the hind femur...........………………...Hadrogryllacris (mostly Australasian; H. rautheri possibly in Ghana).

8A. Upperside of mid tibia spined..................................Echidnogryllacris (Madagascar)
8B. Mid tibia on the upperside without spines, at most with a single spine at the end.................9

9A. Medial vein of elytra simple; cubital vein at most simply forked, or the medial vein forked and the cubital vein simple; only 4 simple postcubital longitudinal veins present............................10 (hereafter Niphetogryllacris – unsure which following characters refer to Afr. Species, so all retained)
9B. Elytra with more veins, or veins even further reduced.....................................13

10A. Elytra about 1.5 x the length of the hind femur, or even shorter....................Niphetogryllacris
10B Elytra about twice as long as hind femur, or even longer......................................................11

11A. Tibia not blackened........................................................................................Niphetogryllacris
11B. Tibia partially blackened........................................................................................................12

12A. Elytral veins matching the ground colour......................................................Niphetogryllacris
12B. Elytral veins at least slightly darkened relative to ground colour; Hind tibiae blackened for about half their length, distinctly cut off.....................................…………………..Niphetogryllacris

13A. Medial vein of elytra pectinate, trifurcate; cubitus simple; Head not so enlarged (as Paragryllacris); frons smooth of inconspicuously punctate. Male with subgenital styli ………………………..…...…...Stictogryllacris (Africa)
13B. Medial vein of elytra, excluding the radial veins, simply or dichotomically divided into branches (never trifurcate).....................................14

14A. Small, inconspicuous, greyish or yellow-brown species with fairly irregular elytral veins. Elytra only reaching end of abdomen. Radial sector usually attached to the otherwise simple medial vein, resulting in distal, section-like branches (=?). In the basal part it is often fused for a distance with the radial vein’s trunk. Cubital vein simple or simply forked............................Atychogryllacris
14B. Larger or differently coloured species, with different venation; (Hind femur normally armed; The movable spines of the fore and middle tibae well developed, or otherwise smaller species with elytra less than 20mm long; Either the middle tibia with four pairs of spines – excluding those at the tip – below, or the tibial spines all greatly reduced. Male genital form not as in Papuogryllacris; Head not so large (as Haplogryllacris, from India) frons smooth or inconspicuously punctate) ....................15

15A. Elytra two to three times the length of the hind femur; Radial sector of elytra from its base completely free; Hindwings hylanine or smoky, elytra differently coloured; ovipositor different (as compared to Melanogryllacris, Malaysia)....................................16
15B. Elytra 1.5 to at most 2 times the length of the hind femur; (Body and limbs without clear metallic-blue sheen; Legs not strikingly long and slim. Colouring of crossveins and ovipositor not as in Marthogryllacris)……………….................................18

16A. Brownish yellow insect; elytra subhyaline with normal, yellowish veins; metazona of pronotum entirely black.....................................Pissodogryllacris (Madagascar)
16B Colouring different to this; (Distinctly larger than 1 cm body length; Elytra double the length of the hind femur or only slightly longer; Pronotum normal-size, at least 1/6th the length of the elytra (8 mm compared to 47mm)).............................17 (Afrogryllacris)

17A. Medium to large, mostly plumper species with sharply defined, dark markings. Elytral veins usually dark; pronotum and back of head often entirely pitchy plack; or the pronotum lined with pitchy black; very often with defined, blackish markings on the limbs; With different (to Chinese Phryganogryllacris) dark markings, or the pronotum more broadly darkened. If not, elytral veins dark (not brownish yellow); Ovipositor at most 1mm longer than the hind femur. Elytral veins often brownish yellow; Occiput and pronotum almost always the same colour. In one case (A. bartschi), the occiput is blackish brown, the pronotal disk is pale yellow. Ovipositor always a little shorter than the hind femur................................Afrogryllacris
17B. At largest medium-sized, slender species, coloured greyish-brown or yellow-brown, sometimes greenish in life, with similarly coloured elytra. No sharply defined, black markings; only the eyes often black; with knees and face below diffuse blackish. Some blackish lines or spots on the face; sides of the pronotum sometimes blurred darker, often the tips of the spines of the hind leg, and the tip of the male’s abdomen, blackenedLarger species of around 30mm body length (min 24mm)……………………......Afrogryllacris

18A. Entirely pitchy black, only the tarsi rust-coloured. Crossveins of the elytra and hindwings edged whitish.......................................................................................Pissodogryllacris (Madagascar)
18B. Hind wings glassy or somewhat smoky, not remotely pitchy-black or glassy-striped; (Colouring otherwise (than Brachybaenus); Male genitals differently formed; colouring otherwise (than Brachybaenus); No such pointed extensions in the area of the Cerci (as in Brachybaenus); Basic colour darker of at least with dark (blackish) elytral veins; if no dark markings, then elytra no more than 1.5 times the length of hind femur.; General colour darker, or at least elytral veins lighter or darker than the body)...……………………………........19

19A. Elytra clearly over one and a half times the length of the hind femur....................................20
19B. Elytra only about one and a half times the length of the hind femur; Body and limbs in part (not entirely) blackich, or the elytral veins not darker than the membrane; Elytral veins not darker than the elytral membraneFrons with dark spots or spots; knees often also blackish………………………….Barombogryllacris

20A. Occiput, knees and tibiae black..............................................................................................21
20B. Occiput and tibiae not black...................................................................................................22

21A. Pronotum entirely brown...........................................................Barombogryllacris (nigriceps)
21B Pronotum iridescent black, only the metazone pale yellow...............Pissodigryllacris (bedoti)

22A. Pronotum dorsally with a dark median longitudinal band...............Niphetogryllacris (eximia)
22B. Pronotum lighter, at most edged with black with the Metazona dark; OR blackish, the metazona and at most the lower margins of the lateral lobes pale.............................Pissodogryllacris

23A. Ovipositor poorly chitinised (?), rolling into a spiral when preserved. Hind-wings always glassy. Elytra often with only 4 simple postcubital veins.............................................Stictogryllacris
23B. Ovipositor well chitinised, not rolling into a spiral. Hindwings often banded. Elytra with at least 5 postcubital veins, the last 2 usually arising from the same stem; (Medial vein of the elytra originating from the radial stem (not cubital stem)).............................................24

24A. Hindwings hyaline or lightly smoky, without dark crossveins; (Fore and Mid tibia with 2-3 (not 4) pairs of spines, excluding the terminal spines; Hind femur below with 2 to 5 spines on each side).......……………………………………………………………….....................Atychogryllacris
24B. Hingwings strikingly coloured or at least with washed out but distinct darkened bands; or at least crossveins along the edge of the wing distinctly darkened; (Hind wings hyaline-tessellated, or brownish-fasciated, dark elements along the crossveins, the light elements in the fields between crossveins. OR hindwing glassy with dark crossveins; Crossveins of elytra only rarely darker than the longitudinal veins, and only exceptionally black lined; in these cases, the elytral length is either under 21mm or over 40mm; Small to large forms, elytral length always under 35mm; Hindwings for the greater part pale; Large types with elytral length 27-33.5mm; Hindwing pale yellowish hyaline and dark or at least with dark crossveins…………………………………………..Gryllacris
(G. tesselata, on Anjouan in the Comoros)

25A. Rudimentary elytra at least 2mm long (Hind tibia of the usual shape; slender, more-or-less flattened above, and provided with small spines; Basal spines of for and middle tibiae not unusually long, only a little longer than the terminal spines; Ovipositor at least 6mm long; Ovipositor only around one and a half times the length of the hind femur, or the parts weakly chitinised and separating into spiral coils in the dead animal. Male, where known, with well developed stylus)…26
25B Rudimentary elytra at most 1.7mm long, or completely absent (Hind tibia above more-or-less flattened, clearly spined)………………………………………........................................….28

26A. Fore and middle tibiae in addition to the terminal spine with 1-2 spines on each side. Male subgenital (plate?) rounded.…………………………………………………….Ametroides
26B. Fore and middle tibiae, in addition to the terminal spines, with 4 spines on each side; (Ovipositor, where known, distinctly more than half the length of the hind femur; Face straw yellow to black; when brown, always without large, light spots. Ovipositor, where known, significantly less than 20mm long, or else more than double the length of the hind femur; Genitals not as in Celeboneanias; Face yellow to yellow brown or black-brown to black; Colouring of face or spination of legs not as in Pareremus atrifrons).………….....….27

27A. Elytra only half as long as the pronotum. Face black. Hind femur with 4 spines on each side undertneath; ovipositor half the length of hind femur.........................................Glomeremus (feanus).
27B Elytra nearly as long as, or as long as, pronotum; (Face straw yellow to yellow brown, at most with 1 or 2 dark markings; hind femur with 3-6 spines (on each side?); Abdomen light-coloured above, at most with chestnut-brown edges of tergites; the end always very light coloured; Ovipositor over twice as long as hind femur, weakkly chitinised and strongly spiralling in prepared specimens)............................................................................................………….............Afroneanias

28A. Fore and middle tibiae beneath, in addition to terminal spines, with 1-2 spines on each side ............................................Ametroides
28B Fore and middle tibiae beneath, in addition to terminal spines, with 3-4 spines on each side ...................................29

29A. Fore and middle tibiae, at least in the latter case, with 3 spines on each side underneath,excepting terminal spines; (Ovipositor over twice the length of the hind femur. Male unknown)………………………………...........Glomeremus (G. shelfordi, Mauritius)
29B Fore and middle tibiae underneath with 4 spines (excluding terminal spines); (Ovipositor, where known, always under 30mm. Male, where known, always with well developed styli; Spination of hindtibia unlike Apteronomus, typically bearing more strongly developed spines) ........................30

30A. Frons rough, at least appearing wrinkled to the unaided eye; (Plain, light, yellow-brown. Head not broader than the pronotum)………………………………………..................Glomeremus
30B. Frons smooth or nearly so, any puncturing or sculpturing only visible under magnification (Head not unusually large, more weakly sculptured (than Giganteremus))……….....................31

31A. Last tergite of male at the reat produced conically upwards; Female unknown. Male with clearly visible rudiments of elytra. Hind femur with only 1-2 spines on each side..........Pseuderemus
31B. Last tergite of male wholly different, or no trace of vestigial elytra. Hind femur with more than 2 spines on at least one side underneath; (Hind femur with more than 3 spines undereneath on at least one side)……………………..............32 (Hereafter all Afrotropical spp. to Glomeremus)

32A. Brown, with striking dark markings (“Zeichnungsmerkmalen”), or at least the abdomen blackened longtitudinally; or with dark spots on the knees............................33
32B. Quite uniformly yellow to rusty brown................................35

33A. Occiput blackish brown to black, clearly and markedly darker than the pronotum.............34
33B Occiput not blackened; (Pronotum pale, gellowish, marked with blackish spots and lines).....Glomeremus

34A. Frons at least partially black; (Frons in the middle dull yellow; as are the clypeus and mandibles. Back of head with yellow spots. Pronotum dull yellow, lateral lobes blackened in the lower part. Abdomen posteriorly blackish.brown, dirty yellow narrowly along the back and in the middle of each tergite)........................... Glomeremus (nitidus)
34B Frons not blackened, usually pale brownish yellow; (The blackening of the occiput does not reach to the rear border of the eyes. Pronotum with large, rust-coloured cross-mark, and often several blackish spots laterally.).......................Glomeremus (pileatus) (Socotra)

35A. Hind femur on at least on one side set with 7-8 spinesApical marginal of male subgenital plate either straight or slightly convex. Ovipositor terminally either bevelled or lightly marginate..............Glomeremus (glomerinus)
35B. Hind femur with no more than 6 spines on either side.....................................36.

36A. Hind femur with 5-6 spines on each side (Female subgenital plate at the end clearly excavated; ovipositor much longer than the hind femur (about twice as long). Male subgenitalia, where known, with two sharp, pike-shaped, backwards-pointing projections)………….Glomeremus
36B. Hind femur at most with 5 spines on ONE side..................................Glomeremus

Posted on August 06, 2021 10:33 by william6 william6 | 2 comments | Leave a comment

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