Contribution to the knowledge of the genus Syndicus Motschulsky (Coleoptera: Staphylinidae: Scydmaeninae) in China Author Yin, Zi-Wei Author Li, Li-Zhen text Zootaxa 2015 3918 3 415 423 journal article 10.11646/zootaxa.3918.3.5 88d0d7e4-a39b-41f1-965b-4f251efa4529 1175-5326 241219 12F611CA-F498-4350-800E-B68474CC6C69 Syndicus ( Semisyndicus ) hainanicus Yin and Li , new species Figs 1 B, 3 Type material (6 ♂♂, 9 ♀♀). Holotype : CHINA : ♂, labeled ‘ China : Hainan Prov., Ledong County [ffi÷θ], Jianfengling [*RΚ], [Mingfeng Valley (d¼☺), 18°44′42″N, 108°50′41″E], 16-IV-2010 , alt. 950 m , ZHU Jian- Qing leg’. Paratypes : CHINA : 3 ♂♂, 4 ♀♀, same locality as holotype , except ‘29[or 30]- IV-2010 , PAN Y.H. & LI W.R. [or PENG & DAI] leg.’; 2 ♂♂, 5 ♀♀, same locality as the holotype , except ‘ 29.iv.2012 , Peng & Dai leg.’. Diagnosis. Males of this new species can be separated from all other Semisyndicus by the unique forms of the aedeagus and spermatheca. Description. Male. BL 2.80–2.82 mm ; body ( Fig. 1 B) moderately convex, dark reddish brown, legs and palpi slightly lighter. Head broadest at large, finely-faceted and moderately convex eyes, HL 0.48 mm , HW 0.61–0.63 mm ; tempora in strictly dorsal view slightly arcuate; vertex strongly transverse, regularly convex, lacking posteromedian longitudinal wrinkle, confluent with small, flattened frons; antennal tubercles slightly prominent; clypeus well demarcated from frons, not modified, with anterior margin nearly straight. Head dorsum glossy, sparsely and finely punctate; setae sparse, moderately long. Antennae ( Fig. 3 A) slightly thickened toward apices, AnL 1.41 mm , relative lengths of antennomeres: 1.1: 1.2: 1.7: 1.7: 1.6: 1.7: 1.7: 1.5: 1.7: 1.4: 1.7. Pronotum elongate with convex, trapezoidal disc, broadest near anterior third; PL 0.85 mm , PWb 0.54–0.55 mm , PWm 0.73 mm ; anterior margin convex; sides strongly narrowing posteriorly and strongly constricted behind middle; posterior collar short, separated from disc by transverse row of four distinct dorsal pits, with oblique lateral groove. Disc finely punctate; setae thin, moderately dense and long. Elytra in lateral view at same level as pronotum, broadest anterior to middle and strongly narrowing toward apices, distinctly flattened near suture in anterior third; EL 1.47–1.49 mm , EW 1.05–1.11 mm , EI 1.33–1.42; humeral calli distinct, protruding anteriorly; punctation similar to that on pronotum; setae about as dense as those on pronotum. Legs moderately long and slender; dorsal femoral groove broad, shallow, and short; all tibiae nearly straight. Aedeagus ( Fig. 3 B–D) slender, AeL 0.58 mm ; endophallus ( Fig. 3 E–F) with complicated system of strongly to weakly sclerotized structures; parameres ( Fig. 3 G) with numerous tiny setae along inner margin from middle to preapical region, distinctly exceed apex of median lobe. FIGURE 3. Diagnostic characters of Syndicus ( Semisyndicus ) hainanicus . A. Antenna. B. Aedeagus, in dorsal view. C. Same, in lateral view. D. Same, in ventral view. E. Aedeagal endophallus, enlarged, in dorsal view. F. Same, schematic. G. Apical portion of paramere, enlarged. H. Spermatheca, in lateral view. I. Same, in axial view. Abbreviations: dag—duct of accessory gland of spermatheca; ds—ductus spermathecae. Scale bars: A = 0.5 mm; B, C, D, E, F = 0.2 mm; G = 0.1 mm; H, I = 0.05 mm. Female. Externally indistinguishable from male. BL 2.67–2.76 mm , HL 0.46–0.47 mm , HW 0.60–0.62 mm , AnL 1.29 mm , relative lengths of antennomeres: 1.0: 1.2: 1.5: 1.5: 1.5: 1.5: 1.4: 1.4: 1.5: 1.5: 1.5. PL 0.81–0.82 mm , PWb 0.54–0.55 mm , PWm 0.68–0.69 mm ; EL 1.40–1.47 mm , EW 1.02–1.08 mm , EI 1.37. Spermatheca ( Fig. 3 H–I) spherical, small, SpD 0.09 mm , with markedly long ductus spermathecae. Comparative notes. This new species has the aedeagal parameres distinctly exceeding the apex of the median lobe. In Semisyndicus , this character state is shared with S . leai leai Franz from Malaysia and Java, S . leai ranongianus Jałoszyński from southern Thailand , and S . sinensis from southwestern China . Syndicus hainanicus can be readily separated from both subspecies of S . leai by the relatively more slender habitus and much longer antennae; from S . sinensis by the smaller body and a different structure of the aedeagal endophallus. The general form and body size of S . hainanicus also resemble those of S . schuelkei from Yunnan, but the structure of the aedeagus and form of the spermatheca are quite different, leading to ready identification of species. Distribution. Southern China : Hainan. Etymology. The specific name refers to the province where the type locality of the new species lies.