Sathytes borneoensis, Shen & Yin, 2019

Shen, Qi & Yin, Zi-Wei, 2019, Four new species of Sathytes Westwood (Coleoptera: Staphylinidae: Pselaphinae) from the island of Borneo, Zootaxa 4629 (2), pp. 188-194 : 189-190

Sathytes borneoensis sp. nov.

( Fig. 1 )

Type material. Holotype: EAST MALAYSIA: ♂, ‘ Borneo: Sabah, Keningau District, Jungle Girl Camp , N5.4430, E116.4512, 1182 m, Shi H.L., Liu Y. lgt., light trap, Ins. Zoo., CAS. 2016. IV.27 ’ ( IZCAS).

Diagnostic description. Male. Body ( Fig. 1A ) dark reddish-brown, mouthparts and legs paler. Body length 2.76 mm. Head slightly wider than long, length from anterior margin of clypeus to base 0.53 mm, width across eyes 0.58 mm. Each eye composed of about 23 facets. Length of eyes (0.26 mm) / length of tempora (0.10 mm) approximately 2.6:1. Length of antennae 1.29 mm; club ( Fig. 1B ) formed by antennomeres 9–11; antennomere 9 ( Fig. 1C ) elongate-oblique, sub-rhomboidal, with elongate sub-basal apophysis slightly broadened at apex; antennomere 10 strongly transverse, obconical; antennomere 11 ( Fig. 1B, 1D ) about 1.6 times as long as wide, with one large, apically setose protuberance and one much smaller tubercle at base. Pronotum about as long as wide, length along midline 0.55 mm, maximum width 0.56 mm. Elytra slightly transverse, length along suture 0.91 mm, maximum width 1.10 mm. Abdomen widest at tergite 1 ( IV), and narrowing apically; mid-length of dorsally exposed part 0.78 mm, maximum width 0.88 mm. Length of aedeagus ( Fig. 1E ) 0.27 mm; median lobe almost symmetric.

Female. Unknown.

Comparative notes. Sathytes borneoensis is most similar to Sathytes clavatus Löbl from Sumatra in the elongate antennomere 9 with an elongate, sub-basal apophysis. These two species may be separated based on the much larger body size (2.76 mm), and antennomere 11 bears a distinct apically setose protuberance and a small basal tubercle of the new species, while S. clavatus is much smaller in size (about 1.9 mm), and antennomere 11 bears a small, indistinct basal lamina visible only in the microscopic preparation.

Distribution. East Malaysia: Sabah.

Etymology. The new species is named after Borneo Island, where the type locality of the new species is situated.

Figures

FIGURE 1. Sathytes borneoensis, male.A. Dorsal habitus. B.Antennal club.C.Antennomere 9. D. Modification of antennomere 11, enlarged. E. Aedeagus, ventral. Scale bars: 0.5 mm in A; 0.2 mm in B; 0.1 mm in C, E; 0.02 mm in D.