Percussiopalpus Jaloszynski & Hlavac 2023, gen. n.
Creators: name: Jałoszyński, Paweł
name: Hlaváč, Peter
name: Anlaş, Sinan
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Percussiopalpus

description: Percussiopalpus Jałoszyński & Hlaváč, gen. n.
(Figs 1‒40)
Type species. Percussiopalpus inusitatus sp. n.
Diagnosis. Thaumastocephalini with sharply delimited frontal sulcus; frontal rostrum gradually broadening posteriorly; tempora abruptly delimited from neck region; posterior tentorial pits situated closer to neck region than to submental bulge; maxillary palpomere 4 with convex distal margin; pronotum approximately cordiform, with lateral foveae, lateral longitudinal sulci and median longitudinal sulcus; mesoscutellar shield about as long as broad; metaventrite with only one pair of foveae (laterad mesocoxal insertion); each elytron with two basal foveae, complete sutural stria and incomplete discal stria; tergite IV with discal carinae and one pair of lateral foveae; sternite IV with pair of submedian foveae directed mesally.
Description. Body (Figs 1, 2) elongate, moderately slender, moderately convex, with distinct constrictions between head and prothorax and between prothorax and elytra.
Head (Figs 3‒7) approximately cordiform, weakly elongate, broadest posteriorly, strongly flattened in posterior half. Temples round, distinctly longer than eyes; vertex and frons confluent, lacking frontal fovea and dorsal tentorial pits (but dorsal tentorial arms are fused with vertex on inner surface of head capsule (Fig. 6; t )), head with broad and shallow V-shaped vertexal and transverse rectangular frontal sulcus (Fig. 3; fs), both confluent; compound eyes (Figs 3–7; ce) minute and situated in front of middle, slightly below median coronal plane of head capsule. Gular sutures lacking; posterior tentorial pits (Figs 5, 7; ptp) large, circular, widely separated, situated in front of transverse impression demarcating neck region ventrally; submental region strongly transverse, with prominent oval submental bulge (Figs 4‒7, 10; smb) strongly projecting ventrally; hypostomal ridge (Fig. 10; hr) short, not reaching margin of submental bulge.
Antennae (Figs 8–9) composed of eleven antennomeres, slender, antennal insertions broadly separated. Scape cylindrical and elongate, longer than pedicel, antennal club trimerous and indistinctly demarcated, antennomere 11 elongate, symmetrical, rapidly narrowing in distal region to pointed apex, lacking cavities and clusters of basiconic sensilla.
Labium (Fig. 10) with elongate mentum (Fig. 10; mn), which is inversely subtrapezoidal, broadest near anterior third, with sinuate lateral margins; prementum short, transverse, lacking ligula; labial palpi (Fig. 10) trimerous, palpomere 1 (Fig. 10; lp1) short, nearly annular, palpomere 2 (Fig. 10; lp2) strongly elongate and weakly clavate, palpomere 3 setiform, barely discernible, obscured by long outer apical seta of palpomere 2.
Maxilla with large, nearly semicircular cardo (Fig. 10; cd); basistipes (Fig. 10; bst) triangular, elongate, mediostipes (Fig. 10; mst) subtriangular, about as long as basistipes; galea (Fig. 10; gal) elongate and with fringe of dense, thick setae along mesal margin; lacinia (not shown) similar to galea but shorter; palpifer elongate. Maxillary palpi (Figs 4–7; mxp, 12, 13) shorter than head, palpomere 1 (Fig. 12; mxp1) minute, elongate, about twice as long as wide; palpomere 2 (Fig. 12; mxp2) pedunculate, rapidly and strongly broadening in distal half, distal region strongly transverse and projecting outwards, with lateral sensory process inserted on conspicuously long and slender petiole broadened distally to form short collar bearing large spherical structure sparsely covered with flattened setae; palpomere 3 (Fig. 12; mxp3) non-pedunculate, strongly transverse and projecting outwards, with similar sensory process as palpomere 2; palpomere 4 (Fig. 12; mxp4) strongly transverse and projecting inwards, elliptical, wider than each of palpomeres 2 and 3, with apical sensory appendage (Fig. 12; sa) rod-like, short and slender, pointed at apex, inserted in socket surrounded by distinctly broadened and raised margin.
Mandibles (Fig. 3; md) subtriangular, slightly convex dorsally and concave ventrally, large, slightly asymmetrical, differing in shapes and numbers of mesal row of several teeth gradually reducing in length towards mandibular base, outer mandibular margin with conspicuously long seta; prostheca and mola lacking.
Labrum (Fig. 11; lr) transverse, subtrapezoidal, broadest anteriorly, with nearly straight anterior and rounded lateral margins; anteroventral margin with one pair of short peg-like sensilla (Fig. 4; pls) inserted on anterior epipharyngeal region.
Pronotum (Fig. 14) widest distinctly in front of middle; lateral margins strongly rounded in anterior half and indistinctly sinuate in posterior half, anterior pronotal margin only slightly shorter than posterior one, anterior corners poorly marked, strongly obtuse-angled, posterior corners distinct, obtuse-angled; pronotal base arcuate. Pronotal disc with long median (Figs 14, 17; mls) and long lateral (Figs 14, 17; lls) longitudinal sulci, lateral sulcus posteriorly originating from asetose lateral antebasal fovea (Figs 14, 17; laf) with short subcuticular pocket, median antebasal fovea (Fig. 14; maf) vestigial, developed as broadening of median longitudinal sulcus and lacking subcuticular pocket; pronotal base with basal and sub-basal pairs of shallow but distinct suboval impressions, and with median impression adjacent to posterior margin.
Prosternum (Figs 15–18) fused with hypomera, but with short grooves on anterior margin representing probable rudiments of notosternal sutures; hypomera (Figs 15, 17; hy) broad and posteriorly weakly concave, each with shallow hypomeral groove (Figs 16, 17; hg) clearly visible in lateral view; basisternal region (Figs 15‒16; bst) much longer than very short coxal region (= furcasternum); prosternum with pair of submedian posterior foveae near middle of posterior basisternal margin, foveal pockets directed dorsally and slightly laterally from body midline (Figs 16, 18; arrowheads); anterior prosternal margin weakly crenulate; prosternal process indistinct, not separating procoxae. Hypomera with hypomeral ridges (Figs 15, 17; hyr) demarcating conspicuously narrow, parallel-sided inner (adcoxal) regions.
Mesonotum (Fig. 25) with mesoscutum and mesoscutellum fused (Fig. 25; sc2+scl2) forming subtriangular scutellar shield, only its minute tip projects posteriorly beyond transverse ridge demarcating basal articulating lobe and discal region of elytra, so that scutellar shield is not visible between elytral bases in intact specimens.
Metanotum (not shown) strongly shortened and weakly sclerotized due to loss of wings.
Mesoventrite (Figs 19–23; v 2) broadening posteriorly, with massive prepectus (Figs 20–23; pp); mesoventrite with three pairs of foveae in its anterior half (Figs 20, 21, arrowheads): one sublateral fovea directed laterally with ventral opening, one lateral fovea directed anteromesally, and one lateral fovea directed mesally, lateral foveae share one large laterally visible setose opening (Fig. 22, upper arrowhead). Median subtrapezoidal area of mesoventrite demarcated laterally by complete ridges. Mesocoxae narrowly separated by elongate, subtriangular mesoventral process (Figs 19, 20, 23; msvp) with rounded apex reaching middle of mesocoxae, meeting, but not fused with anterior tip of anterior metaventral process (Figs 19, 20, 23; amtp), both processes flat. Division between mesoand metaventrite marked with narrow sutures lateral to mesocoxal cavities (visible in Figs 20, 22, 23), but division obliterated within mesocoxal rests.
Metaventrite (Figs 19, 20, 22, 23; v 3) strongly transverse and broadening posteriorly; posterior margins of mesocoxal rests carinate; metaventrite with pair of lateral setose foveae directed anteromesally (Fig. 20, 22, 23; lower arrowhead); metaventral intermetacoxal process (Figs 19, 20, mtvp) broad and clearly separating metacoxae, with posteromedian emargination.
Metendosternite with broad and subquadrate lamellate stem and short lateral furcal arms (Fig. 20; lfa) diverging anteriorly.
Elytra (Figs 22, 24, 25) together subtrapezoidal, dorsally flattened, each elytron with two asetose basal foveae (Figs 24; bef, 25; arrowheads), minute humeral denticle (Fig. 25, hd), short discal stria (Fig. 24, ds), and entire sutural stria (Fig. 24, ss). Posterior elytral margin slightly concave and lacking fringe of modified setae.
Abdomen (Figs 19, 24, 26–30) broadest near middle, weakly convex dorsally and strongly convex ventrally, with well-developed broad paratergites on segments IV–VI. Tergite IV distinctly longer than remaining dorsally visible tergites (i.e., V–VII) combined, with transverse mediobasal impression laterally demarcated by short discal carinae, with one pair of basolateral foveae each adjacent to mesal margin of discal carina and with subcuticular pocket directed laterally (Fig. 28; arrowhead). Sternite III (Figs 19, 26; stIII) short and partly exposed only between metacoxae, with dense fringe of long setae along posterior margin; sternite IV (Fig. 26; stIV) about as long as remaining visible sternites (i.e., V–VIII in female and V–IX in male) combined, with two pairs of foveae: submedian pair with subcuticular pockets directed mesally and touching at midline (Figs 27, 29, right arrowhead), and sublateral pair with pockets directed slightly mesally (Fig. 27; left arrowhead) and strongly dorsally (Fig. 29; left arrowhead). Male with sternite VIII (Fig. 30; stVIII) slightly modified, with trisinuate posterior margin; male sternite IX with large and elongate median penial plate (Fig. 30; stIX), lateral portions subtriangular and shorter than penial plate, weakly visible in intact specimens.
Legs (Figs 1, 2, 15, 19, 20, 22, 23, 26, 31–33) long and slender, all femora slightly clavate, tibiae and tarsi slender; tarsomere 1 (Figs 31–33; t 1) minuscule, tarsomere 2 (Figs 31–33; t 2) longer than tarsomere 3 (Figs 31–33; t 3); tarsal claw only slightly shorter than tarsomere 3; protarsi shorter than half length of tibiae, meso- and metatarsi longer than half length of tibiae.
Aedeagus (Figs 34–38) elongate, with weakly sclerotized walls and asymmetric median lobe bearing oval dorsal diaphragm; endophallic sclerites elongate and asymmetric, parameres (Fig. 37, pr) asymmetric, long and broad, with subapical setae.
Sexual dimorphism. Males with thickened protarsomere 2, submedian ventral tooth on protibiae and sternite IX exposed and tripartite.
Etymology. The name Percussiopalpus refers to the peculiar maxillary palps with sensory processes shaped like percussion mallets, typical of Thaumastocephalini. Gender masculine.
Distribution. Northwestern Anatolia, Turkey (Balıkesir Province).
Species included. Percussiopalpus inusitatus Jałoszyński & Hlaváč.
Remarks. Characters given in the diagnosis all clearly differentiate this genus from Thaumastocephalus; major differences are also compiled in Table 1.
description: Published as part of Jałoszyński, Paweł, Hlaváč, Peter & Anlaş, Sinan, 2023, Percussiopalpus gen. n. from Turkey, a free-living relative of cave-dwelling Thaumastocephalus, and revised placement of Thaumastocephalini (Coleoptera: Staphylinidae: Pselaphinae), pp. 71-90 in Zootaxa 5277 (1) on pages 72-78, DOI: 10.11646/zootaxa.5277.1.3, http://zenodo.org/record/7891898