Scydmaenus (Choleropsis) curviclavatus Jałoszyński 2023, sp. n.
Creators: name: Jałoszyński, Paweł
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Scydmaenus
Scydmaenus curviclavatus

description: Scydmaenus (Choleropsis) curviclavatus sp. n.
(Figs 41–45, 56, 66–67, 74)
Type material studied. Holotype (AUSTRALIA: QUEENSLAND). ♂, “AUST:QLD:ME: / Nob Creek, Byfield / 27 Apr 1979 / G.B. Monteith ” [white, printed], “QM BERLESATE / 22.52S 150.37E / Rainforest / Stick brushing” [white, printed], “ SCYDMAENUS / (CHOLEROPSIS) / curviclavatus m. / P. Jałoszyński, 2023 / HOLOTYPUS ” [red, printed] (QM). Paratypes (17 exx.). QUEENSLAND: 3 ♂♂, same data as for holotype, except for yellow “ PARATYPUS ” labels (cPJ, QM); 1 ♂, “CQld: Mt Fort William / 6 km NE Kalpowar, / 18 Sept 1989. / G.B.Monteith, 700m / Pyrethrum, Rainforest” [white, printed] (QM); 1 ♂, “SEQ:24°32’Sx151°28’E / Bulburin barracks. / 8 Oct 1999. 580m / G.B.Monteith. rainforest / Pyrethrum, trees. 7816 [white, printed] (QM); 1 ♂, “ QUEENSLAND (MEQ) / 8km NW Mt Macartney / 21 Apr 1979 / G.B. Monteith ” [white, printed], “Q.M.BERLESATE NO.49 / 20.49S 148.30E / Dry rainforest, 690m / Stick brushings” [white, printed] (QM); 2 ♂♂, “MEQ:21°35’Sx149°11’E / Cameron Creek, upper, / 100m. 1 Oct 1999. / GB Monteith. pyrethrum / trees, rainforest. 7793” [white, printed] (QM); 2 ♂♂, “AUST:QLD:ME: Brandy Ck / Rd, Conway SF / 23 Apr1979 / G.Monteith” [white, printed], “QM Berlesate No. 56 / 20.20S 148.42E / Rainforest 60m / Stick brushing” [white, printed] (cPJ, QM); 2 ♂♂, “CEQ:22°21Sx149°21’E / St Lawrence, 18,5km W / (rainfor.). 29 May 2000 / GB Monteith. 240m / pyrethrum, trees. 9271” [white, printed] (cPJ, QM); 2 ♂♂, “ Mt Fort William. / Via Kalpowar, C.Qld. / 18 Jan 1990. Monteith / Pyrethrum. Logs” [white, printed] (QM); 1 ♂, “Eungella NP, QLD / Campsite, Broken R. / 8 Jun. 1992 C. Reid / under bark, on trees” [white, printed]; NEW SOUTH WALES: 2 ♂♂ mounted on one card with ant, “Comboyne / N.S.W. / J. Armstrong” [brownish, printed] (ANIC); (ANIC). All paratypes with yellow printed “ PARATYPUS ” labels.
Diagnosis (based on males). Antennomere 9 only slightly shorter than 10, elongate and slightly curved (Figs 66–67); antennomere 10 elongate, with large proximal lateral asetose convexity with subtriangular distal margin (Fig. 67); aedeagus in dorsal view (Figs 42, 44) with apical margin weakly rounded and as wide as about 1/3 of total width of median lobe, lateral subapical lobes small, subtriangular and rounded, each with short setae on apex; in lateral view (Figs 43, 45) distal portion of median lobe delimited by deep submedian constriction, weakly broadened, with dorsal margin broadly rounded in proximal 3/4 and slightly concave near apex; metaventrite (Fig. 74) with deep median impression about as broad as half width of metaventrite and filled with setae slightly shorter than those on lateral regions.
Description. Body of male (Fig. 41) slightly flattened, elongate and slender, BL 1.78–1.90 mm; pigmentation uniformly light to moderately dark brown, appendages indistinctly lighter (difference best visible in darkest specimens); cuticle moderately glossy, covered with vestiture of yellowish setae.
Head (Fig. 41) in dorsal view transversely subrectangular, broadest at eyes, HL 0.30–0.33 mm, HW 0.33–0.35 mm; vertex and frons confluent and weakly convex, posterior margin of vertex distinctly concave, arcuate; tempora nearly as long as 3 × length of eye in dorsal view; supraantennal tubercles indistinct; frons over antennal fossae broadly subtrapezoidal and with straight anterior margin. Eyes small, nearly semicircular in shape, indistinctly emarginate posteriorly and oblique in relation to long axis of head. Punctures on frons and vertex fine, inconspicuous; setae short, sparse, suberect, those on tempora as sparse as those on head dorsum. Genae as sparsely setose as frons and vertex. Anterior (exposed) region of head capsule demarcated from neck region by narrow abrupt impression around occipital constriction, anterior margin of gular plate on neck region accentuated by minute rounded anteriorly-directed projection. Antennae (Figs 41, 56, 66–67) long and slender, AnL 1.03–1.05 mm; three terminal antennomeres forming sharply delimited club; scape about 3 times as long as broad, distinctly broadening distally; pedicel 2.5 × as long as broad; antennomeres 3–4 each 1.5 × as long as broad, 5 twice as long as broad, 6 asymmetrical, 1.8 × as long as broad, 7 and 8 each distinctly transverse and strongly asymmetrical, 9 strongly asymmetrical, elongate and weakly curved, 10 distinctly broader and slightly longer than 9, strongly asymmetrical, with proximal asetose expansion with triangular distal margin; 11 much shorter than 9 and 10 combined, nearly twice as long as broad, slightly asymmetrical.
Pronotum in dorsal view (Fig. 41) elongate, broadest near anterior third, PL 0.50–0.55 mm, PW 0.40–0.45 mm; anterior and lateral margins confluent and rounded; posterior corners obtuse-angled and blunt; posterior margin nearly straight; base with narrow but distinct posterior marginal carina and with two pairs of small, distinct, sharply marked and relatively deep antebasal pits, each slightly transverse. Pronotal disc covered with fine and inconspicuous punctures; setae similar to those on frons and vertex, short, moderately dense, suberect. Ventrally prothorax with nearly asetose and impunctate hypomera; basisternal region sparsely covered with short recumbent setae.
Elytra (Fig. 41) oval, broadest slightly in front of middle, EL 0.95–1.03 mm, EW 0.65–0.70 mm, EI 1.41–1.52. Humeral calli weakly elevated; basal impression on each elytron barely marked; basal elytral foveae lacking; apices separately rounded. Punctures fine and inconspicuous; setae similar to those on pronotum. Hind wings not studied.
Metaventrite (Fig. 74) with deep median impression about as broad as half width of metaventrite and filled with setae slightly shorter than those on lateral regions.
Legs (Fig. 41) long and slender; unmodified, except for distal penicillus on mesotibiae and weakly broadened protarsomere 1 and ventral tenent setae distributed on protarsomeres 1–3; protarsi short, tarsomere 1 about 1.5 × as long as broad, 2–4 each about as long as broad, tarsomere 5 3 × as long as broad and slightly shorter than tarsomeres 2–4 combined; mesotarsi long, tarsomere 1 nearly 4 × as long as broad and subequal in length to tarsomeres 2–4 combined, tarsomeres 2–4 each about 1.5 × as long as broad, tarsomere 5 nearly 3 × as long as broad, subequal in length to tarsomeres 3–4 combined; metatarsi as long as mesotarsi, tarsomere 1 about 3. × as long as broad, tarsomeres 2–4 each elongate but decreasing in length distally, tarsomere 5 3 × as long as broad, subequal in length to tarsomeres 3–4 combined.
Aedeagus (Figs 42–45) elongate but not very slender, AeL 0.35 mm, in dorsal view median lobe broadest in subapical 1/5; apical region subtrapezoidal, strongly tapering and with weakly rounded apical margin as wide as about half of total width of median lobe; lateral subapical lobes prominent and sharply demarcated from median lobe, each subtriangular, about as long as broad, strongly projecting laterally and slightly distally, each lobe with short setae on apex; ostium situated in subapical fourth of median lobe, flagellum with abruptly broadened and asymmetrical vesicular structure; median lobe in lateral view with slender distal portion delimited by deep submedian constriction, with dorsal margin broadly rounded in proximal 3/4 and slightly concave near apex.
Female. Unknown.
Distribution. CE and NE Australia: E and CW Queensland, NE New South Wales.
Etymology. The adjective curviclavatus refers to the curved antennomere 9.
Remarks. Scydmaenus curviclavatus sp. n. externally resembles S. beechmonti, males of both species have somewhat similar antennal clubs. However, in S. curviclavatus the antennomere 9 is only weakly curved, not strongly bent, as that in S. beechmonti. The aedeagi of these species are clearly different, that of S. curviclavatus with short and rounded lateral subapical lobes, whereas the median lobe in S. beechmonti bears large asetose subtrapezoidal subapical lobes, each with a clearly marked distal and proximal corner.
description: Published as part of 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), pp. 1-75 in Zootaxa 5371 (1) on pages 24-26, DOI: 10.11646/zootaxa.5371.1.1, http://zenodo.org/record/10144644