Eupines (Byraxis) platyarthra (Broun, 1893)

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 : 66-67

Eupines (Byraxis) platyarthra (Broun, 1893)

Fig. 43 ; map Fig. 54

Bryaxis clavatus Broun, 1880: 126 .

Bryaxis platyarthra Broun, 1893a: 1417 . New name for Bryaxis clavatus Broun, 1880: 126 , preoccupied by Bryaxis clavata Motschulsky, 1851: 49 .

Eupines (Byraxis) platyarthra : combination and subgeneric assignment by Raffray 1904: 207. Schaufuss 1888: 22; Raffray 1911: 82, 1924: 156; Hudson 1923: 364, 1934: 182; Nomura and Leschen 2006: 255; Maddison 2010: 417; Shen and Leschen 2019: 272 .

Type locality: [CL] Tairua.

Type depository: BMNH LT ♂ ; NZAC 1 PLT .

Diagnosis: Head with vertexal foveae punctiform; antennae 10-segmented with 2-segmented antennal club; A4, A5, A6, A7 and A8 unmodified, A9 largest and strongly transverse, with deep lateral impression and laminate margin at inner side, A10 conical and slightly shorter than A9, lateral side broadly impressed. Abdominal ventrite 2 with pair of minute discal protuberances, inserted with small strongly curved apical setae; ventrite 6 with pair of long median struts, about as long as ventral length. Protrochanters modified with medium-sized ventral spine, about half of protrochanteral width; protibiae and mesotibiae unmodified.

Redescription: Body length 1.60 mm; body colour reddish brown with lighter coloured tibiae and tarsi. Head wider than long; frons not narrowed at end, about three-fourths width of head at eye level; eyes slightly prominent, with about 29 facets; vertexal foveae punctiform; antennal tubercles weak; postantennal notches weak; postantennal cavities small, about half width of antennal tubercles in dorsal view; antennae 10-segmented with 2-segmented antennal club; A4, A5, A6, A7 and A8 unmodified, A9 largest and strongly transverse, with deep lateral impression and laminate margin at inner side, A10 conical and slightly shorter than A9, lateral side broadly impressed. Pronotum slightly longer than wide, about as wide as head at eye level; lacking lateral antebasal foveae. Elytra slightly longer than wide, widest at apical two-thirds; humeral calli slightly prominent; sutural stria shallowly extending from base to apex. Abdomen with tergite 1 about 1.5 × longer than tergite 2; ventrite 2 with pair of minute discal protuberances, inserted with small strongly curved apical setae; ventrite 6 with pair of long median struts, about as long as ventral length. Legs with protrochanters modified with medium-sized ventral spine, about half of protrochanteral width; protibiae and mesotibiae unmodified. Aedeagus about 0.29 mm long, with elongate parameres slightly sinuate, longer than median lobe and basal bulb combined, slightly curved downwards at apex in lateral view, with two pairs of stout subapical setae at inner side, pair of slender subapical setae at outer side and pair of short apical setae; median lobe with two sclerites highly twisted, slightly asymmetrical, gradually narrowed towards apex, both curved inwards at apex.

Comments: This species can be distinguished from all other Eupines by A9 strongly transverse ( Figs. 43 B–D). Distribution: North Island. CL.

Figures

FIGURE 43. Diagnostic characters of E. (B.) platyarthra (Broun, 1893). A) Habitus. B) Antenna, in dorsal view. C) Same, in lateral view. D) Same, in ventral view. E) Ventrite 2. F) Protrochanter. G) Ventrite 6. H) Aedeagus, in dorsal view. I) Same, in lateral view. J) Same, in ventral view. Scale bars: A = 1 mm, B–F = 0.2 mm, G–J = 0.1 mm.

FIGURE 54. Geographic distributions of E. (B.) pannicula sp. n., E. (B.) petila sp. n., E. (B.) platyarthra (Broun, 1893), E. (B.) protibialis sp. n., E. (B.) setifera (Broun, 1893), E. (B.) waikaremoana sp. n., E. (B.) whirinaki sp. n. and E. (B.) undecim sp. n. in New Zealand.