Scydmaenus haigensis, Jałoszyński, 2023

Jałoszyński, Paweł, 2023, Scydmaenus Latreille of Australia: Revision of species in subgenera Choleropsis Franz, Kingius Franz, Mascarensia Franz, Parallomicrus Franz, Scottiscydmaenus Franz, and description of Ascydmaenus subgen. n. (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 5371 (1), pp. 1-75 : 68-70

Scydmaenus haigensis sp. n.

( Figs 182–186 )

Type material studied. Holotype ( AUSTRALIA: QUEENSLAND): ♁ ( Fig. 182 ), “ 17.06S 145.36E QLD / Mt.Haig GS1 1150m / 4Feb.-17Mar.1995 / P. Zborowski FI Traps ” [white, printed], “ SCYDMAENUS / ( ASCYDMAENUS ) / haigensis m. / P. Jałoszyński, 2023 / HOLOTYPUS ” [red, printed] ( ANIC).

Diagnosis. Body large, over 2.4 mm in length; dorsum ( Fig. 182 ) densely setose; head in dorsal view ( Fig. 182 ) strongly narrowing posteriorly and occipital constriction clearly narrower than half width of head; pronotum ( Fig. 182 ) weakly narrowing in posterior half; elytral base ( Fig. 182 ) indistinctly wider than pronotal base; aedeagus in dorsal view ( Fig. 183 ) with lateral margins in subapical region parallel-sided and straight.

Description. Body in male ( Fig. 182 ) strongly convex and stout, BL 2.48 mm; pigmentation uniformly light brown (including appendages); cuticle moderately glossy, covered with vestiture of setae slightly lighter than body.

Head ( Fig. 182 ) in dorsal view indistinctly transverse, strongly rounded, broadest at eyes, HL 0.43 mm, HW 0.48 mm; vertex and frons confluent and weakly convex, posterior margin of vertex nearly straight; tempora about 3 × as long as length of eye in dorsal view; supraantennal tubercles indistinct; frons over antennal fossae broadly subtrapezoidal and with nearly straight anterior margin. Eyes small, oval, strongly oblique in relation to long axis of head, not emarginate posteriorly. Punctures on frons and vertex fine, inconspicuous; setae short and nearly recumbent but dense. Genae similarly setose as dorsum. Anterior (exposed) region of head capsule demarcated from neck region by short abrupt impression around occipital constriction, anterior margin of gular plate on neck region lacking anteriorly-directed projection. Antennae ( Fig. 182 ) long and conspicuously slender, AnL 1.58 mm; three terminal antennomeres forming indistinctly delimited club; scape slightly more than twice as long as broad, distinctly broadening distally; pedicel about twice as long as broad; antennomere 3 2.5 × as long as broad, 4 1.6 × as long as broad, 5 3 × as long as broad, 6 twice as long as broad, 7 and 8 each about 1.8 × as long as broad, 9 about 2.8 × as long as broad, distinctly broadening distally, 10 1.5 × as long as broad, distinctly broadening distally, 11 much shorter than 9 and 10 combined, about 3 × as long as broad and weakly asymmetrical.

Pronotum in dorsal view ( Fig. 182 ) as long as broad, broadest near anterior third, strongly convex anteriorly and flattened in posterior half, PL 0.75 mm, PW 0.75 mm; anterior and lateral margins together strongly rounded; posterior corners weakly marked; posterior margin nearly straight; posterior marginal carina narrow and distinct. Pronotal disc with fine, inconspicuous punctures and densely setose, similarly as frons and vertex. Ventrally prothorax with asetose and impunctate hypomera.

Elytra ( Fig. 182 ) semioval, broadest slightly behind middle, EL 1.30 mm, EW 0.98 mm, EI 1.33. Humeri angulate and projecting anteriorly, but not elevated, basal impressions vestigial; apices separately rounded. Elytra with fine, inconspicuous punctures and densely setose, similarly as pronotum. Hind wings completely reduced.

Metaventrite densely setose.

Legs ( Fig. 182 ) moderately long, robust; profemur with massive, prominent distal tooth nearly as long as broad; protibia strongly thickened distally; protarsus with distinctly broadened proximal half and tarsomeres 1–3 covered ventrally with dense setae, of which only a few have spatulate adhesive tips. Protarsomeres 1–4 each indistinctly elongate, 5 about 2.5 × as long as broad; mesotarsi longer than protarsi, mesotarsomere 1 about 2 × as long as broad, tarsomeres 2–4 each about 1.5 × as long as broad, tarsomere 5 about 3 × as long as broad; metatarsi slightly longer than mesotarsi, metatarsomere 1 2.5 × as long as broad, tarsomeres 2–4 each about 2 × as long as broad, tarsomere 5 about 3 × as long as broad.

Aedeagus ( Figs 183–186 ) elongate and moderately slender, AeL 0.60 mm, in dorsal view median lobe broadest near base, narrowing distally but indistinctly broadening in subapical region, where lateral margins are parallel and straight; apex rounded and with indistinct median notch, with barely discernible, extremely short lateral groups of distal setae; flagellum broadened in proximal region to form three poorly discernible consecutive symmetrical chambers; ostium situated in distal third of median lobe, far from its apex.

Female. Unknown.

Distribution. Known only from NE Australia: CN Queensland.

Etymology. The specific adjective haigensis is derived from the type locality, Mt. Haig.

Remarks. The densely setose dorsum, and the unique shapes of the head, pronotum and elytra allow for an easy and unambiguous identification of this remarkable species.

Figures

FIGURES 182–186. Scydmaenus (Ascydmaenus) haigensis sp. n., holotype male. Dorsal habitus (182); aedeagus in dorsal (183, 185) and lateral (184, 186) views.