Horniella nantouensis Zhang, Hu & Yin, 2021

Zhang, Wen-Xuan, Hu, Fang-Shuo & Yin, Zi-Wei, 2021, Six new species of Horniella Raffray from the Oriental region (Coleoptera, Staphylinidae, Pselaphinae), ZooKeys 1042, pp. 1-22 : 1

Horniella nantouensis Zhang, Hu & Yin sp. nov. Figures 4B , 6 , 10B

Type material.

Holotype: China: ♂, 'TAIWAN: Nantou County, Huisun Forest Reserve [惠荪林场], track to Xiaochushan Mt., 24.0745N, 121.0366E; 1150 m, 4.v.2019; Damaška, Fikáček, Hu & Liu lgt., 2019-TW14 / primary forest on the slope with sparse understory; sifting of small accumulations of leaves / Huisun Leaf Litter Beetles Project, Additional specimen: HS1-034 / HORNIELLA sp., P. Hlaváč det., 2019' (NMNS). Paratypes: China: 1 ♀, same data as holotype, except 'Huisun Leaf Litter Beetles Project, Additional specimen: HS1-035' (NMNS); 1 ♀, 'same locality and date, except ' 24.0826N, 121.0316E; 1050 m, 2019-TW15' / sparse secondary forest with dense understory incl. tree ferns on the margin of a tree plantation: sifting / Huisun Leaf Litter Beetles Project, Additional specimen: HS2-041' (NMNS); 1 ♂, 'Tehuashe (900 m), Nantou, Taiwan, 南投县德化社 (Tehuashe), 14.xi.2000, Hiroshi Sugaya leg. (in the leaf litter)' (MHNG); 1 ♀, same data as previous, except ‘4-5.v.(20)01’ (MHNG); 2 ♀♀, 'Aowanta (1400 m), Nantou, Taiwan, 南投县奥万大, 15.xi.2000, Hiroshi Sugaya leg. (in the leaf litter)' (MHNG).

Diagnosis.

Male. Head longer than wide, with weakly indicated anterolateral genal projection, anterior margin of projection oblique; with short ocular canthus; lateral margin of scape straight, antennomeres 9-11 slightly enlarged. Pronotum rounded at anterolateral margins. Ventral margin of profemur with one short and acute, and one tiny spine at base; protibia with one small preapical denticle. Tergite 1 (IV) with median carina extending posteriorly for approximately 1/3 of tergal length, lacking discal carinae. Aedeagus with asymmetric median lobe, apical part of median lobe narrowed and protruding apicad, apex nearly rounded in dorsal view. Female. Similar to male in external morphology, profemur with two ventral spines near base; genital complex as in Fig. 10B .

Description.

Male. Body reddish-brown, length 3.68 mm. Head (Fig. 6A ) slightly longer than wide, HL 0.74 mm, HW 0.63 mm; anterolateral genal projection weakly developed, anterior margin of projection oblique; antenna 2.03 mm long, scape lacking expansion at lateral margin, antennomeres 2-8 slightly elongate or moniliform, club loosely formed by apical three moderately enlarged antennomeres, antennomere 11 largest, as long as antennomeres 9 and 10 combined; indistinct lateral postantennal pits present; eyes prominent, each composed of approximately 45 large facets, with pair of short ocular canthi (Fig. 6B ).

Pronotum longer than wide, PL 0.77 mm, PW 0.71 mm; widest at apical 1/3; anterolateral margins rounded; disc moderately convex, finely punctate, with distinct median antebasal and lateral antebasal foveae connected by complete transverse antebasal sulcus.

Elytra much wider than long, EL 0.85 mm, EW 1.33 mm; each elytron with two large, setose basal foveae; discal striae extending from outer basal foveae to middle of elytral length.

Legs elongate; protrochanter (Fig. 6C ) simple, profemur (Fig. 6C ) with one short and acute, and one tiny ventral spine at base; protibia (Fig. 6D ) with small preapical spur; mesotrochanter (Fig. 6E ) and mesofemur (Fig. 6E ) simple, mesotibia (Fig. 6F ) with thick apical setae.

Abdomen slightly longer than broad, broadest at lateral margins of tergite 1 (IV), AL 1.32 mm, AW 1.28 mm; tergite 1 (IV) slightly longer than tergites 2 (V), with median carina extending to near basal 1/3 of tergal length, lacking discal carinae, tergite 2 (V) lacking carina, tergites 2-4 (V-VII) each with small basolateral foveae. Sternite 2 (IV) with broad basal sulcus, lacking mediobasal foveae, basolateral foveae developed as large cuticular pockets, with two pairs of antebasal nodules, sternites 3-5 (V-VII) with basolateral foveae, one median and two lateral nodules.

Aedeagus (Fig. 6G-I ) 0.57 mm long, with asymmetric median lobe, apical portion of median lobe narrowed and greatly protruding apically, apex nearly rounded in dorsal view; endophallus composed of broad membranous part with single broad elongate sclerite at middle.

Female. General morphology similar to male, each eye composed of approximately 40 facets; profemur each with two distinct ventral spines near base, protibia lacking spur. Measurements (as for male): BL 3.68-3.72 mm, HL 0.74 mm, HW 0.63-0.65 mm, PL 0.72-0.73 mm, PW 0.74-0.75 mm, EL 0.87-0.9 mm, EW 1.33 mm, AL 1.35 mm, AW 1.32-1.33 mm. Genital complex (Fig. 10B ) with moderately sclerotized central and membranous lateral parts.

Comparative notes.

This species is placed as a member of the H. hirtella group. The new species is similar to H. simplaria Yin & Li by the male having similar anterolateral genal projections, and presence of two ventral spines of profemur. They can be otherwise clearly separated by the larger body size (3.68 mm vs 3.23 mm), lack of a mesal hook-like spine of the protibia (present in H. simplaria ), and the different shape and structure of the aedeagus of the new species.

Distribution.

China: Taiwan.

Etymology.

The new specific is named after its type locality, Nantou County.

Figures

Figure 4. Dorsal habitus of Horniella species A H. khasiensis sp. nov. B H. nantouensis sp. nov. Scale bars: 1 mm.

Figure 6. Diagnostic characters of Horniella nantouensis sp. nov. A left half of head, in dorsal view B head, in lateral view C protrochanter and profemur D protibia E mesotrochanter and mesofemur F mesotibia G-I aedeagus, in dorsal (G), lateral (H), and ventral (I) view. Scale bars: 0.2 mm (A, B, G-I); 0.3 mm in (C-F).

Figure 10. Female genitalia of Horniella species, in dorsal view A H. bifurca sp. nov. B H. nantouensis sp. nov. Scale bars: 0.2 mm.