Horniella burckhardti Yin and Li

Yin, Zi-Wei & Li, Li-Zhen, 2014, Revision of the Oriental genus Horniella Raffray (Coleoptera, Staphylinidae, Pselaphinae), Zootaxa 3850 (1), pp. 1-83 : 45-47

14. Horniella burckhardti Yin and Li , new species

Figs 24 B, 26, 48I; Map 4

Type material (3 ♂♂, 3 ♀♀). Holotype, ♂, labeled ‘ THAILAND, Chiang Mai, Mae Nang Kaeo , 900 m, 54 km NE Chiang Mai , Burckhardt- Löbl, 03.xi.1985 / Holotype [red], ♂, Horniella burckhardti sp. n., det. Yin & Li, 2014, MHNG’ . Paratypes: 2 ♂♂, 3 ♀♀, same data as the holotype . All paratypes are housed in MHNG, and each bears a yellow type label similar to that of the holotype except ‘ PARATYPE ♂ (or ♀)’.

Description. Male ( Fig. 24 B). Length 2.99–3.13 mm. Head about as long as wide, HL 0.67–0.68 mm, HW 0.67–0.70 mm; anterolateral genal projections ( Fig. 26 C) distinct, anterior margins roundly concave; median sulcus between antennal tubercles short, relatively deep; scapes ( Fig. 26 B) roundly expanded at basolateral margins; clubs ( Fig. 26 A) loosely formed by apical three moderately enlarged antennomeres; venter with pair of relatively thick lateral spines ( Fig. 26 D). Maxillary palpomeres II stout, widest near middle. Each eye composed of about 30 facets. Pronotum slightly longer than wide, PL 0.65–0.67 mm, PW 0.62–0.63 mm. Elytra wider than long, EL 0.77–0.78 mm, EW 1.31–1.32 mm; discal striae reaching apical 2/3 of elytral length. Protrochanters and profemora ( Fig. 26 E) each with one thin ventral spine, protibiae ( Fig. 26 F) simple; mesotrochanters ( Fig. 26 G) with short, blunt ventral spine, mesofemora simple, mesotibiae ( Fig. 26 H) with triangular apical projection; tarsomeres II normal, not extending to beneath tarsomeres III. Abdomen large, AL 0.90–1.00 mm, AW 1.22–1.26 mm, tergite IV (first visible tergite) with thick median carina extending to more than apical 2/3 of tergal length, lacking lateral discal carinae, tergite V lacking median carina. Sternite IX ( Fig. 26 I) nearly oval, with well-sclerotized apical half, and membranous basal half. AeL 0.71 mm; aedeagus ( Figs 26 J–L) with nearly symmetric median lobe, apex broadly truncate; endophallus composed of one elongate, twisted sclerite, and two shorter sclerites at middle and base, respectively, of long one.

Female. Similar to male in general appearance; each eye composed of about 25 facets; profemora each with two ventral spines near base, apices mesotibiae lacking projection. BL 2.95–3.09 mm, HL 0.67–0.70 mm, HW 0.62–0.63 mm, PL 0.64–0.65 mm, PW 0.62–0.64 mm, EL 0.76–0.78 mm, EW 1.21– 1.2 mm, AL 0.88–0.96 mm, AW 1.25–1.29 mm. Genital complex ( Fig. 48 I) weakly sclerotized, composed of transverse sclerite.

Differential diagnosis. This species forms the basis of the H. burckhardti group. Males are similar to H. hongkongensis by sharing the evenly concave anterior margins of the anterolateral genal projections, similar placement of spines on the fore and mid legs, and similar aedeagal form. Horniella burckhardti has the scapes conspicuously roundly expanded at the basolateral margins, the median carina of tergite IV extends nearly through the tergal length, and the aedeagal endophallus is composed of one long and two short sclerites, while the basolateral margins of the scapes are slightly expanded, the median carina of tergite IV is much shorter, and the aedeagal endophallus has two sclerites in H. hongkongensis .

Distribution. Thailand: Chiang Mai ( Map 4 ).

Collection notes. Adults were collected from leaf litter samples by sifting and by use of Winkler-Moczarski extractors.

Etymology. The new species is named after Daniel Burckhardt (Basel, Switzerland), in acknowledgment of his collecting efforts in Thailand.

Figures

MAP 4. Distribution of Horniella species in Thailand.

FIGURE 24. Male habitus of Horniella species. A. H. asymmetrica sp. n. B. H. burckhardti sp. n. Scales: 1.0 mm.

FIGURE 26. Male diagnostic features of Horniella burckhardti sp. n. A. Antenna. B. Scape. C. Right half of head, in dorsal view. D. Head, in lateral view. E. Protrochanter and profemur. F. Protibia. G. Mesotrochanter and mesofemur. H. Mesotibia. I. Sternite IX. J. Aedeagus, in dorsal view. K. Same, in lateral view. L. Same, in ventral view. Scales: 0.3 mm, except B, I = 0.1 mm.

FIGURE 48. Female genital complex of Horniella species, in dorsal view. A. H. centralis (Population from Daba Shan). B. H. centralis (Population from Qinling). C. H. hongkongensis. D. H. nakhi. E. H. sichuanica. F. H. himalayica. G. H. hirtella. H. H. asymmetrica. I. H. burckhardti. Scales: 0.2 mm.