Pycnoscelus schwendingeri, Anisyutkin, 2018

Anisyutkin, Leonid N., 2018, New data on the genus Pycnoscelus Scudder, 1862 with the description of P. schwendingeri sp. nov. (Blaberidae: Pycnoscelinae), Revue suisse de Zoologie 125 (1), pp. 79-86 : 80-83

Pycnoscelus schwendingeri sp. nov.

Figs 6-7 , 12-26

Material examined: MHNG, without accession number; male holotype (genital complex in prep. 110817/01); THKN-12/04: Cambodia, Siem Reap Prov., Kbal Spean (13°41’04’’N, 104°01’10’’E), 200 m, semievergreen forest; 27. VI.2013; leg. P. Schwendinger.

Etymology: This species is named in honor of Dr Peter Schwendinger, collector of the holotype of this species and curator of the Arthropoda collections of the Muséum d’histoire naturelle de Genève.

Description:

Somatic characters of male (holotype): General colour yellowish brown, with scattered black spots ( Figs 6-7 ); facial part of head contrastingly coloured ( Fig. 7 ); eyes black; antennae greyish; pronotum, tegmina and abdominal sternites with black spots; legs yellow, partly darkened. Surfaces smooth and lustrous, antennae with proximal 8-10 segments lustrous, the remaining segments dull; pronotum, tegmina, mostly in proximal half, and, to a lesser degree, facial part of head with distinct punctuation. Head slightly longer than wide, with transverse impression between antennal sockets ( Figs 7 , 12 ); ocellar spots small but distinct; distance between eyes about equal to eye length; distance between antennal sockets about 2.5 times scape length (~ 0.6 mm); approximate length ratio of 3rd-5th segments of maxillary palps 1.1: 1.0: 1.2. Pronotum as in Figs 6 , 13 ; cranial margin widely rounded, caudal one distinctly angulate. Tegmina and wings slightly abbreviate, reaching abdominal apex ( Figs 6-7 ). Tegmina with widely rounded apex ( Fig. 6 ), sclerotized in costal field; venation simplified and slightly obliterated along cranial margin; Sc thickened (well visible on ventral side of tegmen); R, M and CuP weak; anal field with obliterated venation. Hind wings membranous, shorter than tegmina, with simplified venation. Fore tibiae distinctly thickened distally ( Fig. 14 ). Anterior margin of fore femora of armed type C, with single apical spine ( Fig. 14 ). Tibial spines well developed. Structure of hind tarsus ( Fig. 15 ): metatarsus about as long as other tarsal segments combined, with large euplantula; spines absent; claws symmetrical, simple; arolium distinct, about half as long as claw. Fore and mid tarsi similar to hind tarsi, but segments comparatively shorter. Abdomen without visible glandular specializations; tergite VIII with distinct spiracle-bearing outgrowths ( Figs 16-17 ), large medial and two smaller oval lateral membranous areas; sternite VIII large, plate-like and weakly sclerotized ( Fig. 18 ). Anal plate (tergite X) weakly sclerotized and asymmetrical ( Figs 16-17 ). Cerci short, with distinct segments. Paraprocts of blaberi-type, with curved hook on right paraproct and with membranous area at cranio-medial angles of left paraproct ( Fig. 17 , par.). Hypandrium asymmetrical ( Figs 19-20 ), with caudal margin weakly concave, hook at caudolateral angle well sclerotized ( Fig. 20 , h.); left stylus absent, right one in shape of elongated triangle.

Genitalia of male holotype ( Figs 20-26 ): Right phallomere ( R + N): caudal part of sclerite R1 T well sclerotized, widely rounded ( Fig. 21 , c.p. R 1 T); bristles absent; R1 T nearly straight; R2 weakly curved; R3 elongated ( Figs 21-22 ); R4 small, not fused with other sclerites; R5 absent; R1 T and R2 cranially prolonged into large sclerotized plate. Sclerite L 2D (L1) divided into basal and apical parts ( Fig. 24 ); basal part robust, widened cranially ( Fig. 24 , b.L 2D ); “apical sclerite” with small teeth at caudal margin ( Figs 23-24 , ap. scl.); bristles absent; “dorsal outgrowth” present ( Figs 23-24 , d.o.). Sclerite L 3 (L2d) without basal subsclerite ( Figs 25-26 ); “folded structure” weakly developed, without bristles ( Fig. 26 , f.s.); apex of L3 with “small tooth” ( Figs 25-26 , s.t.); groove hge absent. Sclerite L 4U (L3d) divided into two parts ( Fig. 25 ) .

Female: Unknown.

Measurements (in mm): Head length 2.6, head width 2.5; pronotum length 4.0, pronotum width 5.8; tegmen length 10.8, tegmen width 3.9.

Comparison: Pycnoscelus schwendingeri sp. nov. belongs to the indicus species-group ( Roth, 1998) judging from the structure of its right stylus. This species-group includes nine species ( Roth, 1998; Anisyutkin, 2002): P. conferta , P. femapterus , P. indicus , P. janetcheki , P. nigra , P. surinamensis , P. gorochovi , P. vietnamensis and P. rothi . The new species readily differs from all species of the indicus species-group by a contrastingly coloured pronotum and facial part of head ( Figs 6-7 ). From P. indicus , P. nigra , P. janetsheki , P. conferta and P. femapterus the new species differs by a distinctly asymmetrical, i.e. emarginated at right side ( Figs 16-17 ), anal plate. The shape of the anal plate is somewhat similar in P. gorochovi , P. vietnamensis , P. rothi and P. schwendingeri sp. nov., but these species can be readily differentiated by the shape of the apical part of sclerite L2D of the male genitalia (compare figs 26-28 in Anisyutkin, 2002 and Figs 23-24 of present paper).

Figures

Figs 6-11. Photos of males of Pycnoscelus schwendingeri sp. nov. (6-7: holotype) and P. striatus (Kirby, 1903) (8-11: specimen from Batu Caves). (6, 8) General view from above. (7, 9) General view from below. (10) Abdominal apex, dorsal view. (11) Same, ventral view. Stylus in Figs 10-11 in everted state. Scale bars 10 mm: a: 6, b: 8. Other photos not to scale.

Figs 12-26. Pycnoscelus schwendingeri sp. nov., male holotype. (12) Facial part of head. (13) Pronotum, dorsal view. (14) Right fore leg seen from anterior (below). (15) Hind tarsus, anterior view. (16) Abdominal apex, dorsal view. (17) Paraprocts and adjacent structures, ventral view. (18) Eighth abdominal sternite, ventral view. (19) Hypandrium, ventral view. (20) Hypandrium and genitalia, dorsal view.(21) Right phallomere, dorsal view. (22) Sclerite R3, ventral view.(23) Caudal part of sclerite L2D, lateral view. (24) Sclerite L2D, dorsal view. (25) Sclerites L3 and L4U, dorsal view. (26) Apex of sclerite L3. Dotted areas show membranous parts. Abbreviations: ap.scl., b.L2D, c.p.R1T, d.o., f.s., h., L4U, par., R2, R3, R4, s.t. - see paragraph “abbreviation used in figures”; for details see text. Scale bars 1 mm: a: 12, b: 13, c: 14, d: 15, e: 16-17, f: 18, g: 19, h: 20, i: 21-24, j: 25, k: 26.

Figs 1-5. Pycnoscelus surinamensis (Linnaeus, 1758), female. (1) Abdominal apex, dorsal view. (2) Genital plate, ventral view. (3) Ovipositor and adjacent structures, ventral view.(4) Ovipositor, ventral view.(5) Basal part of ovipositor, dorsal view. Dotted areas show membranous parts, except for valves of ovipositor in Figs 3-4. Abbreviations: aa., bsv., Cer., gg., par., pl., teVIII., teIX., v.I., v.II., v.III., vs. - see paragraph “abbreviation used in figures”; VIII, IX, X - abdominal tergites VIII-X; for details see text. Scale bars 1 mm: a: 1, b: 2, c: 3, d: 4-5.