Aancistroger inarmatus, 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 : 101

Aancistroger inarmatus sp. nov.

Figs. 32 G–H, 33A–C, 34G

Material examined. Holotype (male): Cambodia: Koh Kong, Tatai , (11°35'13''N, 103°5'50''E), 9–19.x.2016, leg. J. Constant & J. Bresseel (I.G.: 33.345 GTI project)—(Brussels RBINS).

Diagnosis. The new species differs from other species of the genus from which males are known by the absence of apico-lateral spines of the ninth tergite, only the tenth tergite is provided with upcurved spines; it also differs by the peculiar shape of the subgenital plate.

Description. Small to medium sized species. Head: Face narrow ovoid; forehead nearly smooth with very fine transverse riffles; fastigium verticis little wider than scapus; ocelli visible but little distinct; fastigium frontis not clearly separated from fastigium verticis; subocular furrows present but not strong ( Fig. 32H ). Abdominal tergites two and three each with two rows of stridulatory pegs (12–13, 15; 26,>16; n = 1 male).

Wings surpassing stretched hind tibiae ( Fig. 32G ). Tegmen: Radius with two branches, both forked near tip; media anterior free from base but leaning on radius, single branched; cubitus anterior at base single branched, after division into two branches before end of basal quarter, the anterior branch makes a curvature and receives a short connection branch from MA, shortly after it divides into MP and CuA1, which are running parallel; CuA2 without further division; cubitus posterior undivided, free throughout; on the right tegmen only there is a short crossing of CuA with CuP; with 3–4 anal veins; the fourth incomplete and with a long common stem with third anal vein.

Legs: Fore coxa with a 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 10 external and 5–6 internal spines on ventral margins; hind tibia with spaced spines on both dorsal margins, ventral margins with one preapical spine; with 3 apical spurs on both sides; dorso-internal apical spur little curved and about 1.6 times longer than dorso-external spur ( Fig. 34G ).

Coloration. General color uniformly yellowish brown. Face uniformly yellowish or greyish brown, indistinctly marbled in dried specimen. Tegmen semitransparent yellow, along fore and hind margins whitish; veins yellow; hind wing semitransparent white; veins yellow, cross-veins pale.

Male. Eighth abdominal tergite of normal length. Ninth abdominal tergite not globular but sloping posteriorly, only narrow lateral areas bent ventrad; apical margin in middle convex and down-curved forming a transverse lobe; on both lateral angles of this lobe with an inconspicuous, nearly vestigial upright process ( Fig. 33A ). Tenth abdominal tergite hidden under apical lobe of ninth tergite, with a pair of strong, hook-shaped, upright spines ( Fig. 33B ). Subgenital plate with wide, strongly bulging and little convex basal area, followed in middle by a short, transversely grooved central area, and a narrow strongly bulging apical area with bilobate apex, only along lateral margins flattened; without styli ( Fig. 33C ).

Female unknown.

Measurements (1 male).—body w/wings: 27; body w/o wings: 14.5; pronotum: 2.8; tegmen: 23; tegmen width: 7; hind femur: 7.5; antenna: 60 mm.

Etymology. The name of the new species refers to the absence of spines on the male ninth abdominal tergite: from Latin inarmatus (unarmed).

Figures

FIGURE 32. Genus Aancistroger: A–B, A. elbenioides (Karny, 1926); C–D, A. primitivus Gorochov, 2005; E–F, A. vietus Gorochov, 2004; G–H, A. inarmatus sp. nov.—Habitus dorsal view (A, C, E, G); face (B, D, F, H). Scales 10 mm.

FIGURE 33. Genus Aancistroger: A–C, A. inarmatus sp. nov.; D–F, A. vietus Gorochov, 2004; G–I, A. elbenioides (Karny, 1926).—Male abdominal apex in lateral view (A, F–G), apical view (B, D), oblique ventral view (C), ventral view (E, I), dorsal view (H).

FIGURE 34. Genus Aancistroger: A–C, A. elbenioides (Karny, 1926); D–F, A. primitivus Gorochov, 2005; G, A. inarmatus sp. nov.; H, A. vietus Gorochov, 2004.—Habitus lateral view with ovipositor (A, D), apical area of female abdomen with seventh sternite and subgenital plate in ventral view (B, E), apical area of right hind tibia in dorsal view (C, F–H). Scales 10mm.