Euglyptus bifurcatus Byeon & Chandler, 2025

Byeon, Ui-Joung, Chandler, Donald S., Leschen, Richard A. B. & Park, Jong-Seok, 2025, Revision of the New Zealand genus Euglyptus (Coleoptera: Staphylinidae: Pselaphinae) with eight new species, Acta Entomologica Musei Nationalis Pragae 65 (1), pp. 31-59 : 37-38

Euglyptus bifurcatus Byeon & Chandler , sp. nov.

( Figs 3 , 16 )

Type material. HOLOTYPE: J (genitalia dissected), “ NEW ZEALAND, WN, Kaitoke Regional Park, Pakuratahi Forks, 15 Apr 2005, R. Leschen, C. McGuiness, // leaf litter, RL975, 41.03’S, 175.11’E” ( NZAC, NZAC 04261178). PARATYPEs: NEW ZEALAND: NORTH ISLAND: WN [ Wellington]: Tararua FP, Holdsworth, 16 Apr 2005, R. Leschen, leaf litter, RL976, 40.53S, 175.28E (1 J genitalia dissected; NZAC).Orongorongo V, W.N. 15 Nov 1993 // Hard beech forest litter Tullgren #27 (1 J genitalia dissected; NZAC). South Island: BR [Buller]: Maruia Springs 25-Apr-77 (1 J genitalia dissected; JTN). NN [ Nelson]: Slaters Road, 0.7km s Whangamoa Saddle, 410m 13.xii.1984 - 4.i.1985 Nothofagus spp forest A.Newton/M.Thayer 703 // flight intercept (window) trap (1 J genitalia dissected; FMNH / 1 J genitalia dissected; NZAC). 0.6km e Gowanbridge, 330m, 18.xii.84-7.i.85 Nothofagus spp. forest A.Newton/M. Thayer 717 // flight intercept (window) trap (2 JJ genitalia dissected; FMNH). SD [ Marlborough Sounds]: Tennyson Inlet, east side Duncan Bay, 30m 15.xii.1984 - 5.i.1985 podo.- Nothofagus for. A.Newton/M. Thayer 709 // flight intercept (window) trap (1 J slide mounted, 4 JJ genitalia dissected, 2 JJ; FMNH / 1 J genitalia dissected; NZAC / 1 J genitalia dissected; DSC). Tennyson Inlet, west side Te Mako Bay, 125m 15.xii.1984 - 5.i.1985 Nothofagus-podo-hdwd.A.Newton/M.Thayer 710 // flight intercept (window) trap (1 J slide mounted, 5 JJ genitalia dissected, 2 JJ; FMNH).

Diagnosis. Males of this species can be distinguished from other Euglyptus species by the following combination of characters: body 1.14–1.16 mm (forebody 0.84–0.86 mm) ( Fig. 3A ); antennomere X wider than long, widest at apex, as wide as XI ( Figs 3A, C ); pronotum gradually widening from anterior margin to middle, widest in middle, gradually narrowing from middle to posterior margin, with broad and shallow median longitudinal sulcus, with broad transverse antebasal sulcus ( Fig. 3B ); ventral view of left paramere thick, slightly curved to middle, apex bluntly rounded, with prominent preapical truncate apophysis directed to right, right paramere thin, sinuate, obscured by left paramere, broad basally, narrowing and curving ventrally to acute apex; median lobe deeply split apically, with small preapical apophysis best seen in lateral view ( Figs 3E–J ).

Description. Body 1.14–1.16 mm (forebody 0.84–0.86 mm); head and thorax impunctate; head, thorax, and abdomen reddish-brown; elytra, leg, antennal scape, and pedicel lighter than reddish-brown; antennomeres III– VIII, tarsus, maxillary palpus, and antennomeres IX–XI yellowish-brown ( Fig. 3A ).

Head as wide as long, with small dorsal tentorial pits, impression weakly defined around dorsal tentorial pits; temples gradually narrowing toward posterior margin of head capsule, with several setae; impression between antennal tubercles narrow, width of impression area approximately 0.8 times as wide as antennal tubercle diameter. Pedicel wider than antennomeres III–VIII, antennomeres III–V subrectangular, V longer than wide, VI as long as wide, VII slightly larger than VI, VIII smallest, IX as long as wide, subhexagonal, X wider than long, widest at apex, as wide as XI ( Figs 3A, C ).

Pronotum as wide as head, as long as wide, narrowest at anterior margin, gradually widening from anterior margin to middle, widest in middle, gradually narrowing from middle to posterior margin, with broad, shallow median longitudinal sulcus and broad transverse antebasal sulcus ( Fig. 3B ).

Elytra and abdominal tergites without any distinguishing characters ( Figs 3A, D ).

Male genitalia. Ventral view of left paramere thick, slightly curved to middle, apex bluntly rounded, with prominent preapical truncate apophysis directed to right, right paramere thin, sinuate, obscured by left paramere, broad basally, narrowing and curving ventrally to acute apex; median lobe deeply split apically, with small preapical apophysis best seen in lateral view ( Figs 3E–J ).

Etymology. The specific epithet is a Latin adjective referring to the bifurcate apex of the median lobe.

Distribution. New Zealand (North Island: WN, South Island: BR, NN, SD; Fig. 16D ).

Figures

Fig. 3. Euglyptus bifurcatus sp. nov. A – habitus dorsal view; B – pronotum; C – apical antennomeres; D – abdominal tergites IV–V; E, F – aedeagus ventral view; G, H – aedeagus lateral view; I, J – aedeagus dorsal view. Scale bars: A = 1 mm; B–J = 0.1 mm.

Fig. 16. Collection localities of New Zealand for Euglyptus species.