Cephennula minutissima, Jałoszyński, Paweł, 2011

Jałoszyński, Paweł, 2011, Ten new species of Cephennula Jałoszyński (Coleoptera, Staphylinidae, Scydmaeninae) from Malaysia, Zootaxa 3113, pp. 36-52 : 41-42

Cephennula minutissima sp. n.

( Figs. 5 , 17, 18)

Holotype: E MALAYSIA: 3, two labels: " SARAWAK \ Semengoh For. \ 11miSW Kuching \ R.Taylor, 5.68" [white, printed]; " CEPHENNULA \ minutissima m. \ det. P. Jałoszyński, 2011 \ HOLOTYPUS " [red, printed] ( MHNG).

Diagnosis. Body length below 0.7 mm; antennal club slightly flattened and compact; dorsum of head nearly evenly and densely covered with large and deep punctures; punctures on median part of pronotum moderately large and dense; sublateral pronotal carinae fine and obliterated in anterior 1/4 of pronotum; subhumeral carinae nearly as long as half EL and about twice as long as humeral carinae; aedeagus in ventral view drop-shaped, with triangular and blunt apex; endophallus with one pair of elongate sclerites directed towards apex of aedeagus.

Description. Body of male ( Fig. 5 ) strongly convex, elongate, with very shallow constriction between pronotum and elytra, moderately glossy, yellowish-brown, covered with vestiture only slightly lighter than cuticle, legs and antennae slightly lighter. BL 0.68 mm.

Head broadest at large, coarsely faceted and strongly convex eyes, HL 0.08 mm, HW 0.18 mm; vertex and frontoclypeal region convex; supraantennal tubercles barely marked. Punctures on dorsum of head large, deep and dense, nearly equally distributed (minimally sparser in median part of frons); setae very short, sparse and nearly recumbent. Antennae with strongly enlarged, slightly flattened and compactly assembled antennomeres X–XI and only slightly enlarged antennomere IX, so that club appears two-segmented, AnL 0.25 mm; antennomere I about 1.3x as long as broad; II 2.2x as long as broad; III slightly transverse; IV–VI subequal in length and width, each about 1.2x as long as broad; VII slightly broader than VI, about as long as broad; VIII slightly shorter and narrower than VII, slightly transverse; IX distinctly broader and longer than VIII, distinctly transverse; X much longer and broader than IX, strongly transverse; XI about as broad as X, 1.4x as long as broad.

Pronotum approximately semielliptical, broadest between middle and anterior 1/3; PL 0.20 mm, PW 0.28 mm, anterior margin strongly rounded; lateral margins distinctly microserrate, strongly rounded in anterior 1/3, straight in posterior half and slightly convergent towards sharp and acute hind angles; posterior margin very weakly bisinuate; sublateral carinae very fine and obliterated near anterior 1/4 of pronotum. Transverse ante-basal groove very shallow and indistinct, slightly arcuate; sublateral and lateral ante-basal foveae equally small and shallow. Punctures on median part of pronotal disc slightly smaller than those on head, deep and dense, punctures between sublateral pronotal carinae and lateral margins of pronotum distinctly larger and denser, nearly adjacent to each other but not coarse; setae sparse and short, nearly recumbent except for suberect setae along lateral margins.

Elytra strongly convex, oval, broadest between middle and anterior 1/3; EL 0.40 mm, EW 0.33 mm, EI 1.23; base of each elytron with very small but distinct basal fovea located much closer to scutellum than to base of humeral carina; subhumeral carinae distinct, nearly as long as 1/ 2x EL; humeral carinae similarly distinct but about half shorter. Punctures on elytra distinctly smaller than those on head and pronotum, very shallow and with diffused margins, dense; setae very short, sparse, nearly recumbent.

Legs moderately long and slender; pro- and mesotibiae nearly straight, metatibiae slightly curved.

Aedeagus (Figs. 17, 18) in ventral view drop-shaped with moderately broad, subtriangular and rounded apex; AeL 0.18 mm. Endophallus darkly sclerotized, with one pair of weakly curved elongate sclerites directed towards apex of aedeagus; parameres slender, not exceeding apex of median lobe, each bearing single apical seta.

Female. Unknown.

Distribution. East Malaysia (Borneo: Sarawak).

Etymology. The specific epithet “ minutissima ”, Latin "the smallest", refers to the extremely small body of this species.

Remarks. This is the smallest species of Cephennula known so far, and one of two with strikingly short, nearly recumbent vestiture, especially on the elytra. The other Cephennula with such unusually short setae is C. penrissenana , which clearly differs in genital characters.

Figures

FIGURES 3 – 7. Habitus of males. 3 ― Cephennula densepunctata sp. n.; 4 ― Cephennula gemina sp. n.; 5 ― Cephennula minutissima sp. n.; 6 ― Cephennula penrissenana sp. n.; 7 ― Cephennula poringana sp. n. Scale bars: 0.2 mm.