Thaumastocephalus Poggi, Nonveiller, Colla, Pavićević & Rada, 2001

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), Zootaxa 5277 (1), pp. 71-90 : 83-86

publication ID	https://doi.org/ 10.11646/zootaxa.5277.1.3
publication LSID	lsid:zoobank.org:pub:2EBD6E19-89E9-4918-8EE3-3324DF3BBA13
DOI	https://doi.org/10.5281/zenodo.7891956
persistent identifier	https://treatment.plazi.org/id/03AB722F-A107-FFED-25C9-FE2696C8FD75
treatment provided by	Plazi
scientific name	Thaumastocephalus Poggi, Nonveiller, Colla, Pavićević & Rada, 2001
status

Treatment

Thaumastocephalus Poggi, Nonveiller, Colla, Pavićević & Rada, 2001 View in CoL

( Figs 41–55 View FIGURES 41–44 View FIGURES 45–50 View FIGURES 51–55 )

Thaumastocephalus Poggi et al., 2001: 3 View in CoL .

Revised diagnosis. Thaumastocephalini with frontal sulcus with duffuse margin; head behind frontal rostrum abruptly broadening posteriorly in step-wise manner; tempora gradually confluent with neck region; posterior tentorial pits situated closer to submental bulge than to neck region; maxillary palpomere 4 with concave distal margin; pronotum barrel-shaped, lacking lateral foveae and lateral longitudinal sulci; median longitudinal sulcus lacking or faint; mesoscutellar shield strongly elongate; metaventrite with two pairs of foveae (lateral to mesocoxal insertions and just posterior to mesocoxal rests); elytra lacking basal foveae and striae; tergite IV lacking discal carinae, with two pairs of minute lateral foveae; sternite IV lacking pair of submedian foveae.

Redescription. Body ( Fig. 41 View FIGURES 41–44 ) elongate, slender, moderately convex, with distinct constrictions between head and prothorax and between prothorax and elytra.

Head ( Figs 41, 42, 44‒46 View FIGURES 41–44 View FIGURES 45–50 ) distinctly elongate, brodest near middle or slightly anteriorly, strongly flattened in posterior half. Temples rounded; vertex and frons confluent, lacking frontal fovea; dorsal tentorial pits very shallow but accentuated by dark spots marking invagination sites of dorsal tentorial arms, head with broad and shallow U-shaped vertexal-frontal sulcus with diffuse margins; compound eyes lacking. Gular sutures lacking; posterior tentorial pits large, circular, widely separated, situated far anterior to transverse impression demarcating neck region ventrally; submental region strongly transverse, with prominent oval submental bulge strongly projecting ventrally and slightly constricted at base, situated in posterior submental region, close to posterior tentorial pits; hypostomal ridge vestigial.

Antennae ( Fig. 47 View FIGURES 45–50 ) composed of eleven antennomeres, slender, antennal insertions broadly separated. Scape cylindrical and elongate, longer than pedicel, antennal club trimerous and very indistinctly demarcated, antennomere 11 elongate, symmetric, rapidly narrowing in distal region to pointed apex, lacking cavities and clusters of basiconic sensilla.

Labium with elongate mentum which is inversely subtrapezoidal, broadest near anterior third, with sinuate sides; prementum short, transverse, lacking ligula; labial palpi trimerous, palpomere 1 short, nearly annular, palpomere 2 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; basistipes triangular, elongate, mediostipes subtriangular, about as long as basistipes; galea elongate and with fringe of dense, thick setae along mesal margin; lacinia similar to galea but shorter; palpifer elongate. Maxillary palpi ( Fig. 45 View FIGURES 45–50 ) only slightly shorter than head, palpomere 1 minute, elongate, about twice as long as wide; palpomere 2 pedunculate, rapidly and strongly brodening 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 sphaerical structure sparsely covered with flattened setae; palpomere 3 non-pedunculate, strongly transverse and projecting outwards, with similar sensory process as palpomere 2; palpomere 4 strongly transverse and projecting inwards, conspicuosly curved, with concave anterior and convex posterior margin, wider than each of palpomeres 2 and 3, with apical sensory appendage rod-like, short and slender, pointed at apex, inserted in socket surrounded by distinctly brodened and raised margin.

Mandibles subtriangular, slightly convex dorsally and concave ventrally, large, slightly asymmetric, 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 transverse, subtrapezoidal, broadest anteriorly, with nearly straight anterior and rounded lateral margins; anteroventral margin with one pair of short peg-like sensilla inserted on anterior epipharyngeal region.

Pronotum ( Fig. 43 View FIGURES 41–44 ) widest near middle, barrel-shaped, strongly narrowing both anteriorly and posteriorly; lateral margins strongly rounded, anterior pronotal margin subequal in width to posterior one, anterior and posterior pronotal corners strongly obtuse-angled; pronotal base weakly arcuate. Pronotal disc lacking foveae and sulci or with shallow vestiges of asetose median antebasal fovea and faint trace of median longitudinal sulcus.

Prosternum ( Fig. 48 View FIGURES 45–50 ) fused with hypomera, but with short grooves on anterior margin representing probable rudiments of notosternal sutures; hypomera broad and posteriorly convex or indistinctly flattened, each with only trace of barely discernible hypomeral groove; basisternal region much longer than very short coxal region (= furcasternum); prosternum with one pair of submedian posterior foveae near middle of posterior basisternal margin, foveal pockets directed dorsally and slightly outwards from body midline ( Fig. 48 View FIGURES 45–50 ; arrowhead); anterior prosternal margin smooth; prosternal process indistinct, not separating procoxae. Hypomera with hypomeral ridges demarcating conspicuously narrow, parallel-sided inner (adcoxal) regions.

Mesonotum ( Figs51, 52 View FIGURES 51–55 ) with mesoscutum and mesoscutellum fused and forming strongly elongate subtriangular scutellar shield, only its minute capitate tip projects posteriorly beyond basal articulating lobe of elytra, so that scutellar shield is barely visible between elytral bases in intact specimens.

Metanotum vestigial, strongly shortened and weakly sclerotized due to loss of wings.

Mesoventrite ( Figs 49, 50 View FIGURES 45–50 ) broadening posteriorly, with massive prepectus; mesoventrite with three pairs of foveae in its anterior half ( Fig. 50 View FIGURES 45–50 , 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. 44 View FIGURES 41–44 , upper arrowhead). Median subtrapezoidal area of mesoventrite demarcated laterally by complete ridges. Mesocoxae narrowly separated by elongate, subtriangular mesoventral process with rounded apex reaching middle of mesocoxae, meeting, but not fused with anterior tip of anterior metaventral process, both processes flat. Division between meso- and metaventrite marked with narrow sutures lateral to mesocoxal cavities, but division obliterated within mesocoxal rests.

Metaventrite ( Fig. 49 View FIGURES 45–50 ) strongly transverse and broadening posteriorly; posterior margins of mesocoxal rests carinate; metaventrite with pair of lateral setose foveae directed anteromesally just lateral to mesocoxal insertion ( Fig. 50 View FIGURES 45–50 ; upper arrowhead), and pair of setose foveae directed anteromesally just behind posterior margins of mesocoxal rests ( Fig. 50 View FIGURES 45–50 ; lower arrowhead); metaventral intermetacoxal process broad and clearly separating metacoxae, with posteromedian emargination.

Metendosternite with broad and subquadrate lamellate stem and short lateral furcal arms diverging anteriorly.

Elytra ( Figs 51, 52 View FIGURES 51–55 ) together subtrapezoidal, dorsally flattened, lacking humeral denticle, foveae and striae; posterior elytral margin slightly concave and lacking fringe of modified setae.

Abdomen ( Figs 53–55 View FIGURES 51–55 ) 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 poorly marked transverse mediobasal impression and lacking discal carinae, with two pairs of minute basolateral foveae directed laterally ( Fig. 54 View FIGURES 51–55 ; arrowheads). Sternite III short and partly exposed only between metacoxae, with dense fringe of long setae along posterior margin; sternite IV about as long as remaining visible sternites (i.e., V–IX in male) combined, with one pair of lateral foveae directed mesally ( Fig. 55 View FIGURES 51–55 ; arrowhead). Male sternite IX with large and elongate median penial plate, lateral portions subtriangular and shorter than penial plate, weakly visible in intact specimens.

Legs long and slender, all femora slightly clavate, tibiae and tarsi slender; tarsomere 1 minuscule, tarsomere 2 longer than tarsomere 3; tarsal claw only slightly shorter than tarsomere 3; all tarsi shorter than half length of tibiae.

Aedeagus (illustrated in Poggi et al. 2001 and Hlaváč et al. 2019) elongate, with weakly sclerotized walls and asymmetrical median lobe bearing circular or oval dorsal diaphragm; endophallic sclerites elongate and asymmetric, parameres asymmetric, long and broad, with subapical and/or apical setae.

Distribution. Balkan Region: caves in central Dinarides ( Croatia, Bosnia and Herzegovina).

Species included. Thaumastocephalus bilandzijae Hlaváč et al. , T. dahnae Hlaváč et al. , T. folliculipalpus Poggi et al. , T. kirini Hlaváč et al. , T. marsici Hlaváč et al. , T. rujnicensis Hlaváč et al. , T. slavkoi Hlaváč et al. , and T. troglavi Hlaváč et al.