Wow Jałoszyński, Maruyama & Klimaszewski, 2023

Jałoszyński, Paweł, Maruyama, Munetoshi & Klimaszewski, Jan, 2023, Wow assingi gen. and spec. n., with description of a new tribe of Aleocharinae (Coleoptera, Staphylinidae), Zootaxa 5357 (4), pp. 573-586 : 575-580

Genus Wow Jałoszyński, Maruyama & Klimaszewski , gen. n.

Type species: Wow assingi Jałoszyński, Maruyama & Klimaszewski , sp. n. (here designated).

Diagnosis (based on male characters). Body ( Fig. 1 ) strongly flattened; antennae inserted on posterodorsal margin of head capsule, behind line drawn between posterior margins of eyes ( Fig. 4 ); supraantennal tubercles projecting posteriorly on posterior margin of head ( Fig. 4 ); longitudinal subocular ridge (= occipital ‘suture’) absent; labrum ( Fig. 4 ) subrectangular, weakly transverse, weakly emarginate anteriorly; mandibles ( Fig. 4 ) nearly symmetrical, lacking preapical mesal teeth, each with outer dorsal preapical tooth; galea shorter than lacinia ( Figs 7‒8 ); anteromedian region of prelabium posterad ligula with inversely drop-shaped sclerotization ( Figs 10‒11 ); maxillary palpomeres 1 and 2 each bearing several long setae ( Figs 10‒11 ); lateral lobes of labial apodeme short, curved at apices, median projection of labial apodeme short, rounded at apex ( Figs 10‒11 ); scape ( Figs 1‒3 ) conspicuously elongate, longer than pronotum; pronotum ( Fig. 4 ) impressed along midline, with vestiture of setae on central region directed largely laterad, and on lateral regions directed largely mesad; mesoventral process ( Fig. 13 ) subtriangular, barely separating mesocoxae and posteriorly separated from anterior metaventral process; abdomen ( Figs 1 , 16 ) clearly narrower than elytra; tergites III‒V each with flat basal carina laterally curving posterolaterad, on tergite VI only postspiracular portions of carina developed; sternite VIII ( Figs 18 , 25 ) in posterior half triangular and strongly projecting posterad; tarsomeres of all tarsi with conspicuously long ventral setae ( Figs 14‒15 ); ostium of aedeagus ( Figs 19‒20 ) distant from apex of parameral wall; parameres ( Fig. 23 ) with narrow velar region of paramerite and broad, subtriangular apical lobe.

Description (male). Body ( Fig. 1 ) strongly flattened, slender.

Head ( Figs 1‒5 ) with vestigial, barely discernible postocciput, transverse; eyes clearly separated from mandibular bases; clypeolabral connecting membrane ( Fig. 4 ; cmb) nearly as long as broad and with median longitudinal groove; clypeus ( Fig. 4 ; cl) strongly transverse and about 3 times as broad as long, its posterior margin marked by distinct invagination sites of anterior tentorial arms (i.e., anterior tentorial pits; Fig. 4 ; atp); frons and vertex together subtriangular; antennal insertions and supraantennal tubercles ( Fig. 4 ; sat) situated behind eyes on posterodorsal margin of head capsule and strongly elevated, ‘neck ’ absent; antennal foramen within supraantennal tubercle oval and much larger than articulating basal region of scape; longitudinal subocular ridge (= occipital ‘suture’) absent on entire length; gular plate ( Fig. 5 ; gp) subtriangular and slightly narrower than 1/3 of head width (excl. eyes); gular sutures ( Fig. 5 ; gs) complete; posterior tentorial pits ( Fig. 5 ; ptp) distinct, each C-shaped (convex mesally) and strongly elongate, separated by distance shorter than length of pits; hypostomal sutures ( Fig. 5 ; hs) complete and much shorter than submentum; hypostomal ridges ( Fig. 5 ; hr) sharply marked, complete, mesally connected with hypostomal sutures; submentum inversely subtrapezoidal, strongly broadening anteriorly, with anterolateral corners not projecting anterad.

Labrum ( Fig. 6 ; lbr) subrectangular, weakly transverse, weakly emarginate anteriorly, with weakly arcuate sides, subhorizontal, with sparsely and only partly symmetrically distributed numerous dorsal setae, basal labral region asetose; mandibles ( Fig. 6 ; mdb) nearly symmetrical, elongate subtriangular, weakly curved mesally, lacking preapical mesal teeth, each with outer dorsal preapical tooth ( Fig. 6 ; pat); lateral (outer) mandibular margin with distinct longitudinal ventral carina; prostheca ( Fig. 9 ; pst) developed as elongate ventral process with dense and short mesal marginal microtrichia, mola absent. Maxilla ( Figs 7, 8 ) with subtriangular and transverse cardo ( Figs 7, 8 ; cd), subtriangular and elongate basistipes ( Figs 7, 8 ; bst) and elongate mediostipes ( Figs 7, 8 ; mst) distinctly longer than basistipes; palpifer ( Figs 7, 8 ; ppf) strongly elongate; galea ( Figs 7, 8 ; gal) slender, shorter than lacinia (but its anterior margin projecting anteriorly beyond lacinia), with row of short robust setae along outer margin and with long, dense, thin setae on mesal margin; lacinia ( Figs 7, 8 ; lac) slender, with robust apical tooth, subapical mesal row of several thick and nearly rod-like setae and mesal proximal row of dense and thin setae. Maxillary palp tetramerous and slender; palpomere 1 ( Figs 7, 8 ; mxp1) minute and slightly elongate; palpomere 2 ( Figs 7, 8 ; mxp2) pipe-shaped, elongate, curved, sparsely setose; palpomere 3 ( Figs 7, 8 ; mxp3) subequal in width to palpomere 2, strongly elongate and slender, weakly and gradually broadening from base to truncate apex, sparsely setose; palpomere 4 ( Figs 7, 8 ; mxp4) elongate, with truncate apex, weakly and gradually narrowing distally, with subconical apical ‘pseudosegment’ ( Figs 7, 8 ; aps). Labium with broadly subtrapezoidal mentum ( Figs 9‒11 ; mn) and elongate prelabium with ventral inversely drop-shaped median premental sclerotization ( Figs 9‒11 ; msc) bearing two pairs of setae with their insertion sites arranged in nearly a square, proximal (premental) prelabial region transverse, with one setal pore and two real pores, without pseudopores, ligula ( Figs 10, 11 ; lig) in ventral view broadly rounded subtriangular and strongly sclerotized, as broad as distance between labial palps and twice as broad as median premental sclerotization; labial palps trimerous and shorter than prelabium, with palpomere 1 ( Figs 9‒11 ; lp1) subcylindrical and distinctly elongate, bearing several long setae mainly on outer margin; palpomere 2 ( Figs 9‒11 ; lp2) nearly annular, much shorter than 1, with several long setae; palpomere 3 ( Figs 9‒11 ; lp3) shorter than 1 and longer than 2, distinctly broadening toward broadly rounded apex bearing several minute setiform sensilla. Lateral lobes of hypopharynx ( Figs 10, 11 ; llh) narrow and elongate, with dense and thin marginal and ventral microtrichia.

Antenna ( Fig. 1 ) shorter than body but much longer than head and thorax combined, geniculate. Scape conspicuously elongate and clavate, much longer than head, broadest distally to middle. Pedicel much shorter and narrower than scape, weakly clavate. Flagellum nearly filiform and loosely assembled, with antennomeres 3‒10 each broadening distally, antennomere 11 asymmetrical.

Pronotum ( Fig. 4 ) broadest clearly in front of middle, impressed along midline, with conspicuous setal pattern: elongate area at both sides of midline with setae directed posterolaterad near anterior margin, laterad on large median region and anterolaterad near posterior margin; setae on elongate lateral areas of pronotum directed posteromesad near anterior margin, mesad on large median region, and anteromesad near posterior margin. Three pairs of macrosetae ( Fig. 4 ; indicated by arrowheads) present submedially near anterior pronotal margin, sublaterally on disc in front of middle, and submedially near posterior margin. Lateral pronotal carinae largely shifted ventrally and in dorsal view visible only near posterior pronotal corners; hypomera exposed in lateral view, each as wide as about 1/5 width of basisternal region of prosternum (i.e., basisternum fused with preepisternum). Prosternum weakly convex, subtrapezoidal, laterally delimited by short notosternal sutures ( Fig. 5 ; nss), with weakly arcuate anterior margin and broadly subtriangular posterior margin; furcasternum shorter than basisternal region.

Mesoscutellar shield ( Fig. 12 : scs) sub-pentagonal and transverse (exposed portion subtriangular), densely setose.

Mesoventrite ( Fig. 13 ; v 2 ) strongly transverse, with arcuate anterior carina demarcating vestigial prepectus, mesoventral process ( Fig. 13 ; msvp) subtriangular, barely separating mesocoxae, posteriorly separated from anterior metaventral process.

Metanotum not studied.

Elytra ( Fig. 12 ) broadening posteriorly, with weakly concave posterior margins, covered with setae largely directed posterolaterad and each with one macroseta inserted sub-basally on median region of disc ( Fig. 12 ; indicated by arrowhead); epipleural carina absent.

Metaventrite ( Fig. 13 ; v 3 ) subquadrate, mesocoxal rests posteriorly and laterally with fine marginal carinae connected medially on flat and poorly differentiated anterior metaventral process; posterior metaventral margin weakly sinuate on sides and weakly projecting posteriorly at middle, so that metacoxae are subcontiguous. Metaventral discrimen indiscernible, katepisternal sutures marked by faint impression accentuated by transverse row of setae.

Abdomen ( Figs 1 , 16‒18 ) clearly narrower than elytra, nearly parallel-sided in slightly more than anterior half, in posterior half gradually narrowing and truncate at apex; broad bipartite paratergites present on segments II‒VII; tergites III‒V each with flat basal carina laterally curving posterolaterad, on tergite VI only postspiracular portions of carina developed; tergite VII with broad microtrichial field along posterior margin; sternite VIII triangularly projecting posterad; lateral portions of tergite IX ( Fig. 26 ) strongly elongate and with broadly rounded distal regions bearing paired long setae; tergite X ( Fig. 26 ) sub-pentagonal with truncate distal region bearing paired long setae.

Legs ( Figs 1 , 5 , 13‒15 ) moderately long and slender; procoxae ( Fig. 5 ) strongly elongate, each with anterior and posterior marginal longitudinal carina on outer surface ( Fig. 5 ; respectively acxc and pcxc); mesocoxae ( Fig. 13 ) flattened and oval; metacoxae ( Fig. 13 ) subrectangular; pro- and mesotrochanters ( Figs 5 , 13 ) minute and subtriangular, metatrochanters ( Fig. 13 ) much larger but similar in shape; all femora broadest in proximal half and narrowing distally; tibiae slender, with only thin setae, lacking thick spines except for pair of apical spurs; tarsal formula 4-4-4, all tarsomeres with ventral groups of long setae ( Figs 14, 15 ).

Median lobe of aedeagus with ostium distant from apex of parameral wall; endophallus weakly sclerotized, nearly symmetrical; parameres with narrow velar region of paramerite and massive, subtriangular apical lobe bearing 4 macroseate.

Etymology. The generic name Wow (noun in apposition) reflects our first impression ( Wow !) at seeing this extraordinary beetle.

Figures

FIGURES 1–3. Wow assingi sp. n., holotype male. Dorsal habitus, (1); head, pronotum and anterior region of elytra in dorsolateral view (2); head in anterodorsal view (3).

FIGURES 4–5. Wow assingi sp. n., holotype male. Head and prothorax in dorsal (4) and ventral (5) views.Abbreviations: acxc, anterior coxal carina; atp, anterior tentorial pit; bst, basisternal region of prosternum; cl clypeus; cmb, clypeolabral connecting membrane; cs, cervical sclerite; fr, frons; gal, galea; gen, gena; gp, gular plate; gs, gular suture; hr, hypostomal ridge; hs, hypostomal suture; lbr, labrum; mdb, mandible; mn, mentum; mxp1‒4, maxillary palpomere 1‒4; nss, notosternal suture; pcxc, posterior coxal carina; prl, prelabium; pst, prostheca; ptp, posterior tentorial pit; sat, supraantennal tubercle; sc, scape; smn, submentum; trt, trochantin; vt, vertex. Arrowheads indicate macrosetae.

FIGURES 6–11. Wow assingi sp. n., holotype male. Mouthparts in dorsal (6) and ventral (9) views; right maxilla in ventral view (7, 8); labium in ventral view (10, 11). Abbreviations: aps, apical ‘pseudosegment’; atp, anterior tentorial pit; bst, basistipes; cd, cardo; cl, clypeus; cmb, clypeolabral connecting membrane; gal, galea; hr, hypostomal ridge; hs, hypostomal suture; lac, lacinia; lbr, labrum; lig, ligula; llh, lateral lobe of hypopharynx; lp1‒3, labial palpomere 1‒3; mdb, mandible; mn, mentum; msc, median sclerotization of prelabium; mst, mediostipes; mxp1‒4, maxillary palpomere 1‒4; pat, preapical tooth; ppg, palpiger; pst, prostheca; ptp, posterior tentorial pit; smn, submentum.

FIGURES 12–18. Wow assingi sp. n., holotype male. Elytra in dorsal view (12); pterothorax in ventral view (13); protarsus in ventral view (14); metatarsus in lateral view (15); exposed portion of abdomen in dorsal view (16); abdominal apex in dorsal (17) and ventral (18) views. Abbreviations: aest3, metanepisternum; msvp, mesoventral process; scs, scutellar shield; sIII‒VIII, sternite III‒VIII; tII‒X, tergite 2‒10; v2, mesoventrite; v3, metaventrite; 1‒4, tarsomere 1‒4. Arrowhead indicates macroseta.

FIGURES 19–26. Wow assingi sp. n., holotype male. Aedeagus in parameral (19, 21) and lateral (20, 22) views; paramere in lateral view (23); tergite VIII (24); sternite VIII 25); tergites IX and X in dorsal view (26). Abbreviations: apl, apical lobe; con, condylite; hz, hinge zone; par, paramerite; tIX‒X, tergite IX‒X; vel, velum; vst, ventral strut.