Phasmagryllus Desutter-Grandcolas

Desutter-Grandcolas, Laure, 2015, Phalangopsidae crickets from Tropical Africa (Orthoptera, Grylloidea), with descriptions of new taxa and an identification key for African genera, Zootaxa 3948 (3), pp. 451-496 : 475-476

Genus Phasmagryllus Desutter-Grandcolas , n. gen.

( Figs 8–11 )

Type species. Phasmagryllus elegans Desutter-Grandcolas , n. sp.

Etymology. From phasma, meaning ghost in Greek. Genus named after its delicate movements, and ghostly appearance.

Distribution. Known only from Tanzania (eastern Usambara mountains).

Diagnosis. Very small species with contrasted coloration (head orange, antennae bicolor with a wide white ring, legs and body dark brown: Figs 8 , 11 ). Head large, with small, not protruding eyes ( Fig. 8 B), very wide fastigium ( Fig. 8 B) and very elongate maxillary palpi ( Figs 8 C, 9A). TI with a small, inner tympanum and no outer tympanum. TIII with three pairs of apical spurs, the upper ones the longest on both sides; four pairs of subapical spurs ( Fig. 8 D), the first ones the smallest on both sides, the second ones the longest; these spurs alternate and almost aligned in only one row; serrulation sparse above spurs, almost lacking between spurs; all tarsomeres very long, the basitarsomeres III very elongate. FWs present in both males ( Fig. 8 ) and females ( Fig. 11 ), not covering the whole abdomen, not widened in males. Male with a complete stridulum ( Figs 8 E, 9A): harp wider than long, crossed by few oblique parallel veins; mirror crossed by one transverse vein; a distinct transverse cell under the mirror; lateral field with few parallel veins ( Fig. 9 C). Metanotum and tergites with possibly glandular structures ( Fig. 8 F). Subgenital plate short and squared ( Figs 8 G, 9D–F). Male genitalia ( Fig. 10 ) with asymetrical pseudepiphallic processes, each with a hollow spherical base, and each bifid distally, one of these going far beyond distal margin of subgenital plate ( Fig. 8 , arrows); pseudepiphallic parameres well-developed and partly sclerotized; short rami; ectophallic fold very short and membranous; ectophallic apodemes well-developed but short; endophallic sclerite short with a pair of lamellae like apodemes. Female with short, slightly overlapping FWs ( Figs 9 G, 11A, C), with few parallel, convex veins. Subgenital plate transverse ( Fig. 9 I). Ovipositor flattened laterally, the apex smooth and not widened ( Fig. 11 D). Female genitalia as on Fig. 9 J.

Description.

Very small and delicate species ( Figs 8 A, 11A, B), resembling the unrelated Guianese genus Philippopsis Desutter-Grandcolas, 1992 in appearance and contrasted coloration, but still thinner. Very setose. Head very long and large, rounded. Vertex with many strong, widely separate setae. Fastigium very wide, not separate from the vertex ( Fig. 8 B, C), but slanting. Ocelli small, widely apart ( Fig. 8 C); distance between the median and one lateral ocellus smaller than the distance between the lateral ocelli; median ocellus in apical position. Eyes small, not protruding, well apart from each other ( Fig. 8 B). Maxillary palpi very elongate for the subfamily ( Figs 8 C, 9A); joint 3 well shorter than joint 4, which is smaller than joint 5; joint 5 concave dorsally, slightly widened toward apex, truncate obliquely over nearly half its length. Scapes slightly longer than wide ( Fig. 8 B). Pronotum ( Fig. 8 B) transverse, rounded; DD anterior margin slightly concave, posterior margin more concave: lateral lobes squared. Legs very thin but not very elongate ( Figs 8 A, 11A, B). TI with a inner tympanum, small, oval, obliterate; outer tympanum lacking; two ventral apical spurs. TII with two ventral apical spurs. TIII ( Fig. 8 D) with three inner and three outer apical spurs, the ventral the smallest and the dorsal the longest on both sides; inner dorsal spur the longest, about as long as half basitarsomere III. TIII with four pairs of subapical spurs, alternate, but almost aligned on one row; subapical spurs all small, growing longer toward TIII apex, except for the first subapical spur, the smallest; serrulation very sparse, almost lacking between subapical spurs. Tarsomeres long, the basitarsomere III very elongate. Abdomen as collapsed distally, short with narrow tergites. Cerci not particularly long.

Coloration. Species dark brown with contrasted coloration ( Figs 8 B, 11A) on head, DD and antennae.

Male. Metanotum with a pair of high median buds, flattened apically ( Fig. 8 F). Tergites two to five clearly convex along their distal margin, with concave areas near their anterior margins. FWs covering about half abdomen only ( Fig. 8 A), somewhat thickened; cell limits on FW surface very strongly marked ( Fig. 8 E); FW lateral margins almost parallel, the FWs not widened at the mirror level ( Fig. 8 E). Stridulatory apparatus complete, with functional file ( Fig. 9 B): harp wider than long, crossed by few parallel, oblique veins; mirror crossed by one transverse vein; chords occupying a large part of the FWs, the chord 1 widely apart from chords 2 and 3; one transverse cell under the mirror; apical field almost lacking. Lateral field well developed, but shorter than the dorsal field ( Fig. 8 H); few parallel, longitudinal veins ( Fig. 9 C). HWs bud like. Supra anal plate without strong bristles ( Fig. 8 I). Subgenital plate short, wide, truncate ( Fig. 8 G, H).

Male genitalia. Fig. 9 . Small, asymmetrical. Pseudepiphallic sclerite transverse, H-shaped, prolonged lateroventrally by a sclerotization facing the rami ( Fig. 9 , v.ps.); connected to the rami by a thin, lateral sclerite; rami small and dejected ventrally. A pair of median rounded lobes, located distally to the pseudepiphallic sclerite; brisling with small spikes on inner face. A pair of disto-lateral huge pseudepiphallic structures, with a rounded and hollowed anterior part, and a bifid distal part; this bifid part with a short inner lobe and a spine-like outer lobe; left and right inner lobes facing each other; right spine-like lobe short, left one extremely elongate, prolonged far beyond subgenital distal margin ( Figs 9 D, F, 10). Pseudepiphallic parameres located in central position between these pseudepiphallic structures, plicated, with a ribbon-like sclerotization. Ectophallic fold very short, triangular and membranous. Ectophallic apodemes quite long; arc complete. No developped ectophallic dorsal valves. Ventral valves extremely reduced. Endophallic sclerite 3-pronged distally. Endophallic apodemes with a pair of short lamellae. A pair of half-circled transverse sclerites between the endophallic sclerite and the tip of ectophallic fold.

Female. FWs very short and hardly overlapping ( Fig. 11 C); venation made of convex longitudinal veins only ( Fig. 9 G); lateral field very narrow ( Fig. 9 H). Subgenital plate transverse, distal margin bisinuate ( Fig. 9 I). Ovipositor flattened laterally; apex not widened and not ornemented ( Fig. 11 B, D).

Female genitalia. In Phasmagryllus elegans Desutter-Grandcolas , n. sp., copulatory papilla having the shape of a circular sclerite, which membranous center is prolonged by a short and wide, plicated duct ( Fig. 9 J).

Phylogenetic relationships. By its morphology, and more specifically by its head shape (fastigium, ocelli), TIII shape, subapical spurs and serrulation, and male genitalia, Phasmagryllus Desutter-Grandcolas , n. gen. is close to other African Phaloriinae , even though its body shape and way of life resemble other non phaloriine Phalangopsidae such as Philippopsis or Phalangopsis Serville, 1831 in the Neotropical Region, or the African Phaeophilacris Walker, 1871 . These latter genera are straminicolous and cavicolous, foraging at night in the leaf litter, and hiding during the day in cavities at ground level such as burrows or hollow trees ( Desutter-Grandcolas 1992, 1995, pers. obs.). Convergence in body shape due to common habitat might have occurred between Phasmagryllus Desutter-Grandcolas , n. gen. on one hand, and other "truly" long-legged crickets such as Philippopsis , Phalangopsis , Phaeophilacris and the like.

Figures

FIGURE 8. Phasmagryllus elegans Desutter-Grandcolas, n. sp., male holotype. A, dorsal view, scale 1 mm; B, head and pronotum, dorsal view; C, face and maxillary palpi; D, hindtibia, dorsal view; E, right forewing, dorsal view; F, metanotum and tergite structures, dorsal view; G, subgenital plate, ventral view; H, subgenital plate and right forewing, lateral view; I, supra anal plate, dorsal view. Arrows point to the left pseudepiphallic distal process, which is extremely long.

FIGURE 9. Phasmagryllus elegans Desutter-Grandcolas, n. sp. A, maxillary palpus, female allotype; B, C, venation of dorsal and lateral fields of male holotype FWs; D-F, male holotype subgenital plate, ventral (D), right side (E) and left side (F), with projections of asymmetrical pseudepiphallic processes; G, H, venation of dorsal and lateral fields of female allotype right FW; I, female allotype subgenital plate, ventral view; J, female allotype copulatory papilla. Scale bars 1 mm.

FIGURE 10. Phasmagryllus elegans Desutter-Grandcolas, n. sp., male holotype, genitalia in dorsal (A), ventral (B) and lateral (C) views. Abbreviations see page 3.

FIGURE 11. Phasmagryllus elegans Desutter-Grandcolas, n. sp., female allotype. A, dorsal view, scale 1 mm; B, lateral view; C, pronotum and FWs, dorsal view; D, ovipositor, lateral view.