Asarcogryllacris (Pseudolarnaca) cornualis, 2018

Ingrisch, Sigfrid, 2018, New taxa and records of Gryllacrididae (Orthoptera, Stenopelmatoidea) from South East Asia and New Guinea with a key to the genera, Zootaxa 4510 (1), pp. 1-278 : 127-128

Asarcogryllacris (Pseudolarnaca) cornualis sp. nov.

Figs. 42 H–O

Material examined. Holotype (male): East Malaysia: Sabah, Tawau district, Tawau Hills , (4°24'N, 117°54'E), 5.ix.2009, leg. A. Floren (tree T48 [7T48])—(Bonn ZFMK).

Other specimens: Sabah: same locality, 6.ix.2009, leg. A. Floren (tree T58 [7T58])— 1 female (paratype) (Bonn ZFMK); same locality, 6.ix.2009, leg. A. Floren (tree T60 [7T60])— 1 male (paratype) (Bonn ZFMK) .

Diagnosis. The new species agrees with both other species of the subgenus ( A. (P.) genualis and A. (P.) nigroscutata ) in general habitus, size, and wing venation. It differs remarkably by its dull greyish color with black hieroglyphic pattern on pronotum ( Figs. 42H, L ) instead of being yellowish with a well outlined black mark on pronotum. More important are the differences in male and female abdominal appendages. The male ninth abdominal tergite carries a pair of large half-moon-shaped projections with dentate margin ( Fig. 42O ) while two pairs of small obtuse projections in A. (P.) genualis sensu Gorochov (2005) , and the projection of the male paraproctes of A. (P.) cornualis carry at tip a disc-shaped expansion instead of a subacute tip. The female of A. (P.) cornualis differs from those of the other species by the shape of the seventh abdominal sternite that terminates into a large and wide membranous projection that covers the base of the apically truncate subgenital plate ( Fig. 42I ) instead of a small narrow projection and an apically rounded subgenital plate.

Description. Small to medium sized species. Head: Face rather narrow; forehead nearly smooth; fastigium verticis little wider than scapus; ocelli small, white, little distinct ( Fig. 42J ). Abdominal tergites two and three each with two rows of extremely weak stridulatory pegs: (0–6, 5–9; 4–6, 6–7; n = 1 male, 1 female).

Wings reaching about tip of hind femur ( Figs. 42H, L ). Tegmen widest in about mid length: Radius releases RS only in apical quarter of tegmen (both males) or RS divides in apical area from MA (female); media anterior fused in about basal third with radius, fused vein markedly thickened; shortly after MA divides from R, it divides again into MA and MP (both males); in this case cubitus anterior remains single-branched throughout. In the female, MA divides only near tip of tegmen into two branches, probably RS and MA, while MP has a common stem with CuA, it divides after basal third in a curvature and then divides again into MP and CuA. Cubitus posterior undivided, free throughout; with 3 anal veins (all specimens).

Legs: Fore coxa with small spine at fore margin; fore and mid femora unarmed; fore and mid tibiae with four pairs of large ventral spines and one pair of smaller ventral spurs; hind femur with small spines on both ventral margins, with 10–11 external and 10–18 internal spines on ventral margins, increasing in size towards posterior end; hind tibia with spaced spines on both dorsal margins, ventral margins with one pre-apical spine each; with 3 apical spurs on both sides.

Coloration. General color light greyish brown (originally conserved in alcohol), vertex with a black band. Face light yellowish brown with dark brown or black bands along fastigial suture, along interrupted clypeo-frontal suture, from below compound eyes to base of mandibles, and with a marked comma-shaped black stroke from and including ventro-internal angle of antennal scrobae to about mid-length of frons; mandibles dark brown; antennal flagella darkened. Pronotum with irregular black lateral bands and black rim, hind femur on external surface with serrated black dorsal and ventral bands, a thin black middle stroke and hind knees black; all femora in progenicular and tibiae in subbasal areas with dark spots. Abdominal tergites with black lateral bands. Tegmen in about basal half brownish transparent, towards tip transparent with brown veins (3 main veins [cubitus + analis 1+2] black in basal area); hind wing transparent with brownish veins.

Male. Ninth abdominal tergite strongly curved down posteriorly and triangularly narrowing to a narrow truncate tip; on both sides of tip with moveable about half-moon shaped projections with dentate apical margin and a large tooth at external angle ( Figs. 42 N–O). Paraproctes with a short upcurved membranous process that carries at tip a granular, roughly circular disc with strengthened rim. Subgenital plate rather short, transverse, with styli about as long as plate; apical margin slightly bilobate ( Fig. 42H ). Phallus membranous.

Female. Seventh abdominal sternite normal, as preceding sternite with a faint medial furrow, widening apically ( Fig. 42I ). Subgenital plate with long membranous basal area that carries a faintly sclerotised, irregular, reddish brown spot at each side; plate transverse with converging lateral and subtruncate apical margins, separated from membranous part by a transverse furrow. Ovipositor about half as long as hind femur, moderately strong upcurved; before tip narrowing, tip subacute ( Fig. 42K ).

Measurements (2 males, 1 female).—body w/wings: male 23–25, female 26; body w/o wings: male 15, female 17; pronotum: male 4–5, female 4.5; tegmen: male 17–18, female 19; hind femur: male 15.0–16.5, female 16.5; tegmen width: male 6, female 5.2; antenna: male 130–180, female 165; ovipositor: female 9.5 mm.

Etymology. The new species is named for the shape of the projections of the male ninth abdominal tergite; from Latin "cornualis" half-moon-shaped.

Figures

FIGURE 42. Genus Asarcogryllacris subgenus Pseudolarnaca: A–G, A. (P.) genualis (Walker, 1869) male from Brunner's collection (BrW26.384, A–C) and female from Khao Chong (D–G); H–O, A. (P.) cornualis sp. nov. female paratype (H–K), male paratype (L) and male holotype (M–O).—Habitus dorsal view (A, H, L), left tegmen (D), face (E, J), male abdominal apex in apical (B, O), oblique ventro-apical (C), ventral (M) and oblique lateral view (N), female seventh abdominal sternite and subgenital plate (G, I), ovipositor (F, K).