Eupines (Byraxis) caesta, Shen & Leschen, 2020

Shen, Jia-Wei & Leschen, Richard A. B., 2020, Revision of Eupines King of New Zealand (Coleoptera: Staphylinidae: Pselaphinae: Goniaceritae), Zootaxa 4777 (1), pp. 1-84 : 15

Eupines (Byraxis) caesta sp. nov.

Fig. 7 ; map Fig. 49

Diagnosis: Head with vertexal foveae punctiform; antennae 10-segmented with 2-segmented antennal club; A4, A5, A6, A7 and A8 unmodified, A9 transverse, cupulate, A10 largest, irregularly cup-shaped, broadly excavated at ventral side. Abdominal ventrite 2 and ventrite 6 unknown. Protrochanters with long and acute ventral spine, slightly shorter than protrochanteral width; protibiae and mesotibiae unmodified.

Description: Body length 1.33 mm; body colour reddish brown with lighter coloured tarsi. Head slightly wider than long; frons not narrowed at end, about three-fourths width of head at eye level; eyes well developed, slightly prominent in dorsal view; vertexal foveae punctiform; antennal tubercles weakly developed; postantennal notches shallow and broad; postantennal cavities small, about half length of antennal tubercles in dorsal view; antennae 10-segmented with 2-segmented antennal club; A4, A5, A6, A7 and A8 unmodified, A9 transverse, cupulate, A10 largest, irregularly cup-shaped, broadly excavated at ventral side. Pronotum as long as wide, slightly narrower than head at eye level; lacking lateral antebasal foveae. Elytra as long as wide, widest near middle; humeral calli barely visible in dorsal view; sutural stria shallowly extending from base to apex. Abdomen with tergite 1 about 1.6 × longer than tergite 2; ventrite 2 and ventrite 6 unknown. Legs with protrochanters modified with long and acute ventral spine, slightly shorter than protrochanteral width; protibiae and mesotibiae unmodified. Aedeagus unknown.

Comments: Only the holotype is known. We did not attempt to dissect the holotype since the male has an irregularly cup-shaped A10 ( Figs. 7 B–C) that differentiates this species from other members of Eupines .

Distribution: North Island. NN.

Etymology: This specific epithet is a Latin noun meaning ‘glove’, referring to the irregularly cup-shaped antennomere 10.

Type material ( NZAC): Holotype. ♂, specimen entire, glued on card, one proleg mounted on acetate card: “ 19.xii.1951, moss, nr. L. Omapere, N.I. P772 [handwritten]”.

Figures

FIGURE 7. Diagnostic characters of E. (B.) caesta sp. n. A) Habitus. B) Antenna, in dorsal view. C) Same, in ventral view. D) Protrochanter. E) Abdomen, in ventral view. Scale bars: A = 1 mm, B–E = 0.2 mm.

FIGURE 49. Geographic distributions of E. (B.) anisarthra (Broun, 1914), E. (B.) bisulcifrons (Broun, 1914), E. (B.) brevis sp. n., E. (B.) caesta sp. n., E. (B.) carinata sp. n., E. (B.) coalita sp. n., E. (B.) complector sp. n. and E. (B.) conspicua (Broun, 1893) in New Zealand.