Revision of subgenera of Stenichnus Thomson, with review of Australo-Pacific species (Coleoptera, Staphylinidae, Scydmaeninae) Author Jałoszyński, Paweł text Zootaxa 2013 3630 1 39 79 journal article 10.11646/zootaxa.3630.1.2 28703b77-1579-49e7-885f-5c2edb895f83 1175-5326 283467 A338EE37-E8AC-4AC3-8D6B-D0177FB680BF Scydmaenilla ( Scydmaenilla ) pusilla King , stat. rest. ( Figs. 74–83 ) Scydmaenilla pusilla King, 1864: 93 . Stenichnus ( Scydmaenilla ) pusillus (King) ; Franz, 1975: 136 (redescription based on a misidentified specimen, not S. pusilla !). Lectotype designation. King (1864) described S. pusilla on the basis of two syntype specimens. Although the female ( Fig. 75 ) is better preserved, the species diagnosis is based primarily on the unique aedeagus, and therefore the male ( Fig. 74 ) is here designated a lectotype to ensure the stability of nomenclature and to provide a unique name-bearing type for Scydmaenilla pusilla . The syntypes were mounted on one card ( Fig. 76 ); they were remounted on separate cards and pins during the present study and the male lectotype retained the original set of labels ( Fig. 77 ), while the female paralectotype was provided with copies. Material studied . Lectotype (here designated) 3: three labels ( Fig. 77 ): " Scydmaenilla / pusilla / 160" [yellowish, handwritten in faded black or blue], "1523/36" [yellowish, handwritten in faded black or blue], and a more recent label with a museum collection number "K 197803" [white, printed] (AMS); paralectotype , Ƥ: labels as for lectotype (AMS) Diagnosis. Body distinctly flattened, length ca. 1 mm ; elytra moderately slender, EI nearly 1.5; antennal club symmetrical; metatibiae with sub-apical setal brushes; lateral metaventral carinae absent; short median longitudinal groove on posterior pronotal collar absent; lateral marginal pronotal carinae well-marked; aedeagus strongly elongate, with broadened apex. Redescription. Body of male ( Fig. 74 ) flattened, elongate and moderately slender, with long appendages, BL 1.06 mm ; glossy, uniformly light brown with appendages barely lighter than body; vestiture yellowish. Head ( Fig. 79 ) approximately subtriangular, broadest at eyes, HL 0.20 mm , HW 0.23 mm ; tempora distinctly shorter than eyes; vertex distinctly transverse and weakly, evenly convex, anteriorly confluent with frons; frons convex; supraantennal tubercles barely marked; eyes moderately large and convex, bean-shaped and nearly transverse in relation to the long axis of head. Punctures on head dorsum fine and sparse, inconspicuous; setae short, sparse, suberect. Antennae ( Fig. 74 ) slender, with distinctly enlarged club composed of antennomeres IX–XI, AnL 0.43 mm ; antennomeres I–VI elongate, VII–VIII each about as long as broad; IX–X distinctly transverse, XI 1.6 × as long as broad. Pronotum ( Fig. 74 ) in dorsal view with oval anterior part and short posterior collar, broadest near anterior fourth, PL 0.29 mm , PW 0.25 mm ; anterior and lateral margins confluent and rounded; sides in posterior third indistinctly constricted demarcating short posterior part; hind pronotal corners blunt and obtuse; posterior margin distinctly arcuate; base of pronotum with narrow and deep ante-basal transverse groove connected laterally to shallow but distinct triangular impressions; lateral marginal carinae well-developed in posterior half of pronotum. Punctures on pronotal disc very fine and inconspicuous, those behind ante-basal groove dense and distinct but shallow and with diffused margins; setae moderately long, sparse and suberect. Elytra ( Fig. 74 ) oval and only slightly more convex than pronotum, broadest distinctly anterior to middle, EL 0.60 mm , EW 0.41 mm , EI 1.45; humeral calli distinct, developed as elongate protuberances; elytral apices separately rounded. Punctures on elytral disc forming indistinct longitudinal rows, well-visible only near distinctly raised suture in anterior 2/3 of elytra, laterally and posteriorly punctures gradually reducing in diameters and depth; setae moderately long and sparse, suberect. Hind wings not studied. Legs ( Fig. 74 ) long and slender; all tibiae straight or nearly straight, metatibiae with sub-apical setal brushes. Aedeagus ( Figs. 82–83 ) strongly elongate, slender, AeL 0.25 mm , in the only known male with partly damaged apex; apical part broadened; internal armature darkly sclerotized, with a pair of subtriangular sclerites; parameres long and slender, each with one apical seta and several setae distributed latero-ventrally along distal 2/3 of paramere; bases of parameres surrounding basal orifice darkly sclerotized. Female ( Figs. 75 , 78–81 ). Externally similar to male, differs slightly in measurements: BL 1.08 mm ; HL 0.18 mm , HW 0.23 mm ; AnL 0.45 mm ; PL 0.28 mm , PW 0.25 mm ; EL 0.63 mm , EW 0.43 mm , EI 0.47. Distribution. Southeastern Australia : eastern New South Wales . Remarks . According to the original description (King 1864) the syntypes were collected in Paramatta (today a suburb of Sydney). The body silhouette of S. pusilla in dorsal view is highly similar to that of S. thompsoniana . These two species share similar proportions of body parts (including the pronotal and elytral indexes), but S. pusilla can be easily distinguished on the basis of a flattened body (strongly convex in S. thompsoniana ), much more distinct lateral marginal carinae of pronotum, less distinct elytral punctation, a raised elytral suture and a symmetrical antennomere X (slightly asymmetrical in S. thompsoniana ).