Bellendenker, Jałoszyński, Paweł, 2017

Jałoszyński, Paweł, 2017, Bellendenker gen. nov., a new Australian genus of Glandulariini (Coleoptera: Staphylinidae: Scydmaeninae), Zootaxa 4247 (2), pp. 165-173 : 166-171

Bellendenker gen. nov.

Type species. Bellendenker palpalis sp. nov. (here designated).

Diagnosis. Glandulariine genus with uniquely modified labial palps: palpomeres I and II extremely elongate so that labial palps are longer than labium; mandibles falciform, each with distinct mesal tooth located near basal third; eyes located posteriorly, distant from mandibular bases; clypeus much longer than labrum; frontoclypeal groove absent; labrum densely and asymmetrically setose; occipital constriction slightly narrower than frons between eyes; antennae gradually thickened distally; head and prothorax with thick bristles; pronotum broadest indistinctly in front of middle, with three pairs of antebasal pits; prothoracic hypomera lacking hypomeral ridges, each with subrectangular adcoxal lobe, with its anterior margin perpendicular to and connected with notosternal suture; basisternal portion of prosternum slightly shorter than procoxal cavities; prosternal process narrow, carinate, weakly elevated; mesoventrite with distinct pair of impressed procoxal rests separated at middle but not demarcated posteriorly; mesoventral intercoxal process broad, parallel-sided, moderately strongly elevated; metaventral intermetacoxal process subtriangular, narrowly separating metacoxae and with distinct median notch; each elytron with two rudimentary basal foveae covered by pronotal base in intact specimens, lacking basal impressions and humeral calli; hind wings absent; mesocoxa with two tufts of setae on dorsal surface; median lobe of aedeagus and endophallus symmetrical, parameres free, slender, lacking apical setae; spermatheca globular, asymmetrical.

Description. Body ( Fig. 1 ) around 1.7 mm, strongly convex, elongate but moderately slender, distinctly constricted between head and pronotum and between pronotum and elytra, with long appendages, pigmentation brown; cuticle setose.

Head ( Figs 1 , 3–5 ) divided by occipital constriction into exposed anterior part and posterior part largely retracted into pronotum; anterior part elongate, distinctly flattened, narrower than pronotum, broadest at eyes; frons ( Fig. 3 ; fr) and vertex ( Fig. 3 ; vt) confluent, together about as long as broad, weakly convex, posterior margin of vertex demarcated from 'neck' by broad impression; tempora ( Fig. 3 ; tm) about as long as eyes in dorsal view, strongly convergent posteriorly and nearly straight, with thick bristles; supraantennal tubercles distinct but relatively weakly elevated; clypeus ( Fig. 3 ; cl) strikingly long, posteriorly at middle confluent with frons; compound eyes large and strongly projecting laterally, coarsely faceted.

Labrum ( Figs 3, 5 ; lbr) strongly transverse and short, densely and asymmetrically setose. Mandibles ( Figs 3–6 ; md) symmetrical, falciform, each with broad mandibular base ( Fig. 6 ; mb) rapidly narrowed at small, subtriangular mesal tooth located near proximal 1/3 of mandible, distal portion of mandible strikingly long and slender, pointed and curved, setose prostheca present but not visible in intact specimens. Maxillae and maxillary palps do not deviate from ground plan of Glandulariini . Labium ( Figs 4–6 ) with large submentum ( Figs 4–6 ; smn) not demarcated laterally by sutures, but with faint ridges extending posteromesally from cardines; subtrapezoidal mentum ( Figs 4–6 ; mn); and very long, largely membranous prementum ( Figs 4–6 ; pmn) bearing narrowly separated at bases labial palps composed of short, annular palpomere I ( Fig. 6 ; lp1), very long palpomere II ( Fig. 6 ; lp2) narrowing distally and about five times as long as broad at base, and extremely long and slender palpomere III ( Fig. 6 ; lp3) narrowing distally, weakly curved and about ten times as long as broad at base, labial palps are longer than labium; area between labial palps with a pair of long setae, but not forming defined ligula. Hypostomal ridges ( Fig. 4 ; hr) complete, strongly curved posteromesally and with their posterior ends recurved posteriorly, not connected and distant from posterior tentorial pits.

Gular plate ( Fig. 4 ; gp) large and subtrapezoidal, with rapidly narrowed unsculptured anterior portion; gular sutures indistinct; posterior tentorial pits ( Fig. 4 ; ptp) narrow and strongly elongate, located in front of transverse impression ventrally demarcating 'neck' region.

Antennae ( Fig. 1 ) long and slender, gradually but only slightly thickened distally; antennomeres compactly assembled.

Prothorax ( Figs 1 , 7–9 ) in dorsal view elongate and broadest slightly in front of middle, with rounded anterior margin and anterior portions of lateral margins; anterior corners not marked; posterior corners distinct but blunt and nearly right-angled; posterior margin nearly straight. Base of pronotum with three pairs of distinct antebasal pits ( Fig. 7 ; abp) not connected by groove, lacking lateral or sublateral carinae or edges. Sides of pronotum covered with thick bristles well visible in dorsal view.

Prosternum with moderately long basisternal part ( Fig. 8 ; bst) demarcated from procoxal cavities ( Fig. 8 ; pcc) by arcuate and diffused ridges densely covered with setae; median part of sternum carinate but weakly elevated, forming prosternal process ( Fig. 8 ; psp) not separating procoxae; procoxal sockets closed by posterolateral lobes of prosternum; hypomera ( Fig. 8 ; hy) elongate, each divided into broad lateral part confluent with pronotum and narrower, elongate subrectangular inner (adcoxal) part with anterior margin perpendicular to notosternal suture ( Fig. 8 ; nss; largely obscured by dense setae), the latter complete; hypomeral ridges absent.

Mesocutellum subtriangular, in intact specimens not exposed, entirely hidden under posterior margin of pronotum overlapping with elytral base.

Mesoventrite ( Fig. 10 ) with massive and demarcated anterior ridge ( Fig. 10 ; ar); mesoventral intercoxal process ( Fig. 10 ; msvp) subrectangular, broad, parallel-sided, moderately elevated; anterior portion of mesoventrite with a pair of shallow setose impressions functioning as procoxal rests ( Fig. 10 ; pcr), their posterior margins indistinct; mesanepisternum with long prepectus ( Fig. 10 ; pre), sides of mesoventrite with setose ventrolateral and dorsolateral foveae ( Fig. 9 ; vlf, dlf); mesocoxal projections ( Fig. 10 ; mcp) prominent, with mesocoxal sockets located on their mesoventral surface and exposed in ventral view.

Metaventrite ( Fig. 10 ; v3) short, anteriorly fused with mesoventrite, posteriorly deeply bisinuate and with broadly subtriangular metaventral intercoxal process ( Fig. 10 ; mtvp) bearing distinct inversely drop-shaped median notch. Metanepisterna and metepimera narrow, in intact specimens covered by elytra.

Elytra ( Figs 1 , 9 ) oval, strongly convex, lacking humeral calli and basal impressions, each with two asetose rudiments of basal foveae ( Fig. 7 ; bef).

Hind wings absent.

Legs ( Figs 1, 1–13 ) long and robust; pro- and mesocoxae subglobose, metacoxae strongly transverse; all trochanters short and subtriangular; all femora strongly and gradually clavate; tibiae and tarsi moderately slender, terminal tarsomere with distinct empodium ( Fig. 13 ; e mp) emarginated distally and bearing two long setae. Mesocoxae ( Figs 11 ¯12) with largely asetose dorsal surface (adjacent to mesocoxal cavity) bearing two bunches of long setae.

Aedeagus ( Figs 14–17 ) elongate, thin-walled, with symmetrical median lobe and symmetrical, weakly sclerotized endophallus; parameres free and thick, lacking long setae.

Spermatheca ( Fig. 18 ) globular, asymmetrical, moderately thick-walled.

Etymology. Bellendenker is named after the type locality, Mt. Bellenden Ker in Queensland, which, in turn, was dedicated to an English botanist of the XVIII–XIX c., John Bellenden Ker Gawler. Gender masculine.

Remarks. Bellendenker differs from all genera of Glandulariini , except for Scydmaenozila , in peculiar ventral structures of the prothorax: the adcoxal portion of each hypomeron forms an elongate subrectangular lobe with its anterior margin perpendicular in relation to the notosternal suture, and the lobe is not demarcated from the outer portion of hypomeron (i.e., lacking hypomeral ridge). This structure can be found only in Bellendenker and Australian Scydmaenozila ; these genera share all prothoracic, most pterothoracic structures, and two tufts of setae on the dorsal surface of mesocoxae. These are almost certainly sister taxa, but they differ in a number of easily observable features: i) the clypeus in Bellendenker is strongly elongate, much longer than labrum, not declined and not demarcated from frons (in Scydmaenozila clypeus much shorter than labrum, declined and demarcated by distinct frontoclypeal groove); ii) the distance between compound eye and mandibular base in Bellendenker is about twice as wide as that between eye and posterior margin of vertex (in Scydmaenozila the distance between eye and mandibular base is about as wide or slightly shorter than that between eye and posterior margin of vertex); iii) the mandibles in Bellendenker are extremely slender, with the mesal tooth located in basal 1/3 (in Scydmaenozila mandibles short and broad, with mesal tooth located in distal 1/4); iv) the labial palpomeres II and III in Bellendenker are strikingly elongate, together much longer than entire labium (in Scydmaenozila labial palps do not differ from those in all remaining Glandulariini , i.e., they are shorter than labium); v) the hypostomal ridges in Bellendenker are strongly curved mesally (in Scydmaenozila straight, extending posteromesally); vi) the labrum in Bellendenker is covered densely with more than 50 asymmetrically distributed setae (in Scydmaenozila only about 15 mostly symmetrically distributed setae); vii) in Bellendenker the basal elytral foveae are rudimentary and barely discernible in intact specimens, basal elytral impressions are absent, humeral calli are rounded and indistinct, and wings absent (in Scydmaenozila elytral foveae are deep and large, located in distinct basal impressions, well discernible in intact beetles, humeral calli prominent, and hind wings well developed); viii) in Bellendenker the metaventral intercoxal process is deeply notched at middle, the notch is inversely drop-shaped (in Scydmaenozila posterior margin of metaventral process is indistinctly, broadly emarginate); ix) in Bellendenker the endophallus is simple, composed of weakly sclerotized structures (in Scydmaenozila the endophallus is complicated, composed of a large number of at least partly strongly sclerotized structures).

Figures

FIGURES 1 – 2. Bellendenker palpalis sp. nov., holotype male; dorsal habitus (1) and distribution (2).

FIGURES 3 – 6. Bellendenker palpalis sp. nov.; head in dorsal (3), ventral (4) and lateral (5) views; mouthparts in ventral view (6). Abbreviations: cl, clypeus; fr, frons; gp, gular plate; hr, hypostomal ridge; lbr, labrum; lp, labial palp; lp 1 – 3, labial palpomere I – III; mb, mandibular base; md, mandible; mn, mentum; mt, mesal tooth; mxp, maxillary palp; occ, occipital constriction; pmn, prementum; ptp, posterior tentorial pit; smn, submentum; tm, temple; vt, vertex.

FIGURES 7 – 10. Bellendenker palpalis sp. nov.; prothorax in dorsal (7), ventral (8) and lateral (9) views; pterothorax in ventral view (10). Abbreviations: abp, antebasal pit; ar, anterior ridge; bef, basal elytral fovea; bst, basisternal part of prosternum; dlf, dorsolateral fovea; hy, hypomeron; mcp, mesocoxal projection; mscc, mesocoxal cavity; msvp, mesoventral process; mtvp, metaventral process; nss, notosternal suture; pcc, procoxal cavity; pcr, procoxal rest; pre, prepectus; psp, prosternal process; vlf, ventrolateral fovea; v 3, metaventrite.

FIGURES 11 – 13. Bellendenker palpalis sp. nov.; mesocoxa in dorsal view (11); setal tufts on mesocoxa (12); apex of protarsomere V in ventral view (13). Abbreviations: cx, coxa; emp, empodium; fe, femur; tr, trochanter.

FIGURES 14 – 18. Bellendenker palpalis sp. nov.; aedeagus in ventral (14, 16), and lateral (15, 17) views; spermatheca (18).