Plexigryllacris megastyla, 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 : 268-273

Plexigryllacris megastyla spec. nov.

Fig. 99 A–F

Material examined. Indonesia: West Papua, Tamarau Mts., Fef vill. ca 11 km W, elev. 800 m (0°46'12''S, 132°19'56''E), 13.ii.2012, leg. D. Telnov— 1 male (Erfurt NKME) .

Diagnosis. P. megastyla sp. nov. is so far the only species of the genus. Its deviations from the related genus Papuogryllacris are already outlined under genus.

Description. Small species. Head: Face ovoid; forehead dull with scattered shallowly impressed dots; fastigium verticis little narrower than scapus; ocelli distinct; fastigium frontis separated from fastigium verticis by a transverse suture; subocular furrows absent ( Fig. 99B ). Abdominal tergites two and three each with two rows of stridulatory pegs (4, 6; 6,>8; n = 1).

Wings surpassing tip of abdomen and hind knees of stretched hind legs ( Fig. 99A ). Tegmen: Radius releases RS in about mid-length of tegmen; both veins fork near tip; media anterior free from base, unbranched; cubitus anterior at base with a single branch that forks behind basal third into two veins; cubitus posterior undivided, free throughout; with 4 anal veins, last two with common stem.

Legs: Fore coxa with a spine at fore margin; fore and mid femora unarmed; fore and mid tibiae with 3 pairs of large ventral spines and 1 pair of small ventral spurs; hind femur with 8–9 external and 11–12 internal spines on ventral margins, increasing in size towards posterior end; hind tibia with spaced spines on both dorsal margins, ventral margins without pre-apical spine; with 3 apical spurs on both sides.

Coloration. General color light brown, disc of pronotum with four black spots. Face greyish brown, in middle with a vertical dark brown band below compound eyes; fastigii and bases of antennae dirty yellowish brown with small black spots on top and in middle of fastigium verticis, on both upper angles of fastigium frontis and just below ventro-internal angle of antennal scrobae; fastigium verticis on both sides with a distinct elongate triangular white fascia; ocelli also white; clypeus and labrum dirty yellowish brown; mandibles dark brown, palpi yellowish. Tegmen semi-transparent yellowish, darker towards base, almost white near tip; veins and veinlets yellow; hind wing semi-transparent white with yellowish veins and veinlets.

Male. Eighth abdominal tergite of normal size ( Fig. 99C ). Ninth abdominal tergite in dorsal view only little longer than preceding tergites, with apical margin concave on both sides and continued ventrally into large membranous zones, only lateral margins and a rather narrow central area curved ventrad; from both ventro-apical margins of the sclerotised lateral areas with a long projection, that is moderately wide at base and gradually narrowing towards acute tip, while the narrow sclerotised central area moderately widens laterally at ventral end; from both large membranous zones and encircled by the sclerotised lateral and central areas of the ninth tergite a pair of large, compressed and twisted projections arise (probably remnants of tenth tergite) that free from the membranous surfaces and are provided with a small but sharp tooth at tip; at rest, the latero-apical spines of the ninth tergite are resting in the curvature of that tooth ( Figs. 99 E–F). Subgenital plate wide and very short; apical margin in middle with rather narrow projection with bilobate tip; styli about as long as plate and medial projection together and very stout, their bases filling the whole space between the lateral margin and the medial process of the plate ( Fig. 99D ).

Female unknown.

Measurements (1 male).—body w/wings: 25; body w/o wings: 17; pronotum: 3.5; tegmen: 20.5; tegmen width: 5.5; hind femur: 11 mm.

Etymology. The new species is named for the very large styli.

Figures

FIGURE 99. Plexigryllacris megastyla gen. nov. & sp. nov., male holotype: A, Habitus dorsal view; B, face; C–F, abdominal apex in dorsal (C), ventral (D), apical (E), and oblique lateral view (F). Scale 10 mm.