Linan Hlaváč, 2002

Yin, Zi-Wei, Li, Li-Zhen & Zhao, Mei-Jun, 2011, A review of the genus Linan (Coleoptera: Staphylinidae: Pselaphinae), Acta Entomologica Musei Nationalis Pragae 51 (1), pp. 123-135 : 124-126

Genus Linan Hlaváč, 2002

( Figs. 1–48 )

Linan Hlaváč, 2002: 294 . HLAVÁČ & CHANDLER 2005: 110.

Type species. Lasinus chinensis Löbl, 1964 , by original designation.

Diagnosis. The genus Linan could be readily separated from allied genera within the Pselaphodes complex by the following combination of characters: Head with vertexal and frontal foveae indistinct; maxillary palpi with segments III–IV asymmetrical, roundly expanded or with external protuberance; pronotum with small but well-defined median and lateral antebasal foveae; head, pronotum and legs densely and roughly punctate; median metaventral fovea present; metaventral horn-like processes present in male; elytra simple without carinae.

Redescription. Length 2.35–3.63 mm. Head, antennae, pronotum, abdomen and legs reddishbrown, elytra lighter, maxillary palpi and tarsi yellowish-brown.

Head nearly triangular, roughly punctate, sparsely covered with pubescence; frontal fovea and pair of vertexal foveae very indistinct; antennae elongate, pubescent; scape roughly punctate, about as long as segments II–V combined; antennal club three-segmented; antennomeres IX–X strongly modified or not in male, not modified and weekly clubbed in female.

Pronotum about as long as wide, roughly punctate, pubescent. Width of the elytra wider than long, pubescent; each elytron with two basal foveae; discal stria reaching apical twothirds of elytral length. Legs elongate and slender with femora roughly punctate, usually simple without spine (except for L. cardialis ); protibiae in some species expanded mesally at apex as a spur or lobe in male; tarsi three-segmented. Venter with metaventrite depressed, smooth; median metaventral horn-like processes paired and well-defined in male, various in length and shape; median metaventral foveae present.

Abdomen with first visible tergite (morphological tergite IV) largest, discal ridges present or absent; following segments successively shorter and narrower; paratergites well-defined. Aedeagus with median lobe large; parameres paired; endophallus provided with various types of sclerites.

Discussion. Species of the genus Linan can be classified into two groups (here proposed): the L. cardialis species-group, with strongly modified antennal segments IX–X and modified protibiae at apex in male, including L. cardialis , L. hainanicus , and L. megalobus sp. nov., and the L. chinensis species-group, lacking obvious sexual modifications of the male antennal club and protibiae, containing L. chinensis and L. inornatus sp. nov.

Figures

Figs. 1–4. Male habitus of Linan spp. 1 – L. cardialis Hlaváč, 2002; 2 – L. chinensis (Löbl, 1964); 3 – L. hainanicus Hlaváč, 2002; 4 – L. inornatus sp. nov.

Figs. 5–6. Dorsal habitus of Linan spp. 5 – L. megalobus sp. nov., male; 6 – L. sp. indet., female.

Figs. 7–11.Antennal segments VIII–XI of Linan spp. in male. 7 – L. cardialis Hlaváč, 2002; 8 – L. chinensis (Löbl, 1964); 9 – L. hainanicus Hlaváč, 2002; 10 – L. inornatus sp. nov.; 11 – L. megalobus sp. nov. Scales: 0.3 mm.

Figs. 12–21. Pronotum and metaventral horn-like processes of Linan spp. in male. 12, 17 – L. cardialis Hlaváč, 2002; 13, 18 – L. chinensis (Löbl, 1964); 14, 19 – L. hainanicus Hlaváč, 2002; 15, 20 – L. inornatus sp. nov.; 16, 21 – L. megalobus sp. nov. Scales: 0.2 mm.

Figs. 22–26. Details of legs of Linan spp. in male. 22 – protrochanter and profemur of L. cardialis Hlaváč, 2002; 23 – mesotrochanter and mesofemur of L. cardialis; 24 – protibia of L. cardialis; 25 – protibia of L. hainanicus Hlaváč, 2002; 26 – protibia of L. megalobus sp. nov. Scales: 0.3 mm.

Figs. 27–41. Aedeagus and sternite IX of Linan spp. 27, 29, 31, 33, 35 – aedeagus, in dorsal view; 28, 30, 32, 34, 36 – aedeagus, in lateral view; 37–41 – sternite IX of Linan spp. 27, 28, 37 – L. cardialis Hlaváč, 2002; 29–30, 38 – L. chinensis (Löbl, 1964); 31–32, 39 – L. hainanicus Hlaváč, 2002; 33–34, 40 – L. inornatus sp. nov.; 35–36, 41 – L. megalobus sp. nov. Scales: 0.2 mm (a, b, c, d, e); 0.1 mm (f, g, h, i, j).

Fig. 42. Distribution of the genus Linan Hlaváč, 2002. Black squares – L. cardialis Hlaváč, 2002; white triangle – L. chinensis (Löbl, 1964); white squares – L. hainanicus Hlaváč, 2002; white circle – L. inornatus sp. nov.; black circle – L. megalobus sp. nov.; black triangle – L. sp. indet.

Figs. 43–48. Habitats of the genus Linan Hlaváč, 2002. 43 – Nabanhe Nature Reserve, Yunnan (L. cardialis Hlaváč, 2002); 44 – Longwangshan Mountain, Zhejiang (L. chinensis (Löbl, 1964)); 45 – Bawangling Nature Reserve, Hainan (L. hainanicus Hlaváč, 2002); 46 – Tianzhushan Mountain, Anhui (L. inornatus sp. nov.); 47 – Kuankuoshui N. R., Guizhou (L. megalobus sp. nov.); 48 – Sanqingshan Mountain, Jiangxi (L. sp. indet.).