Eupines (Byraxis) illustris (Broun, 1914)

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 : 40-41

Eupines (Byraxis) illustris (Broun, 1914)

Fig. 25 ; map Fig. 51

Byraxis illustris Broun, 1914b: 168 . Hudson 1923: 364, 1934: 185.

Eupines (Byraxis) illustris : combination and subgeneric assignment by Nomura and Leschen 2006: 255. Maddison 2010: 417; Shen and Leschen 2019: 267 .

Type locality: [ MC] Broken River , Canterbury .

Type depository: BMNH LT ♂, 1 PLT .

Diagnosis: Head with vertexal foveae punctiform; antennae 10-segmented with 3-segmented antennal club; A4, A5, A6, A7 and A8 unmodified, A9 large and asymmetrical, strongly transverse and obliquely truncate at apex, with lateral acute spine, A10 largest and conical, with basal excavation. Abdominal ventrite 2 with pair of large discal protuberances, inserted with strongly curved large apical trichomes; ventrite 6 unknown. Protrochanters with minute ventral spine, about one-tenth of protrochanteral width; protibiae and mesotibiae unmodified.

Redescription: Body length 1.64 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 moderately developed, with about 31 facets; vertexal foveae punctiform; antennal tubercles weak; postantennal notches weak; postantennal cavities large, about as long as antennal tubercles in dorsal view; antennae 10-segmented with 3-segmented antennal club; A4, A5, A6, A7 and A8 unmodified, A9 large and asymmetrical, strongly transverse and obliquely truncate at apex, with lateral acute spine, A10 largest and conical, with basal excavation. Pronotum about as long as wide, wider than head at eye level; lacking lateral antebasal foveae. Elytra as long as wide, widest at about apical three-fourths; humeral calli slightly prominent; sutural stria distinctively extending from base to apex. Abdomen with tergite 1 about twice length of tergite 2; ventrite 2 with pair of large discal protuberances, inserted with strongly curved large apical trichomes; ventrite 6 unknown. Legs with protrochanters modified with minute ventral spine, about one-tenth of protrochanteral width; protibiae and mesotibiae unmodified. Aedeagus unknown.

Comments: Only two type specimens are known. We did not dissect syntypes since males of this species have distinctive A9 modifications and two tufts of large trichomes on ventrite 2 ( Figs. 25 B–C) that can immediately differentiate it from congeners.

Distribution: South Island. MC.

Figures

FIGURE 25. Diagnostic characters of E. (B.) illustris (Broun, 1914). A) Habitus. B) Antenna, in dorsal view. C) Abdomen, in ventral view. Scale bars: A = 1 mm, B–C = 0.2 mm.

FIGURE 51. Geographic distributions of E. (B.) glabrata (Broun, 1886), E. (B.) graceae sp. n., E. (B.) halli (Broun, 1921), E. (B.) hectori (Broun, 1895), E. (B.) hoarei sp. n., E. (B.) huizhenae sp. n., and E. (B.) illustris (Broun, 1914) in New Zealand.