Bryaxis girinensis Choi, Park, Lee & Park, 2023

Choi, Yeon-Jae, Park, Sun-Jae, Lee, Seung-Gyu & Park, Jong-Seok, 2023, Five new species of Bryaxis Kugelann (Coleoptera, Staphylinidae, Pselaphinae) from Korea and a nomenclatural note on Bryaxis mahunkai Loebl, ZooKeys 1182, pp. 165-181 : 165

Bryaxis girinensis Choi, Park, Lee & Park sp. nov.

Figs 7 , 9A, C, E

Type material

(N = 1, 1 ♂). Holotype male. "Korea: Gangwon Prov. Bangdong-ri, Girin-myeon, Inje-gun, 23 Jun 2009, sifting flood debris, T.-K. Kim, CNUIC" (NIBR).

Diagnosis.

Antennal pedicels less enlarged subglobose, with dorsolateral glandular nodule on subapical (Fig. 7C, D , arrows); protibiae with spine on internal side at widest point (Figs 7E , 9C , arrows); parameres of male genitalia with depression on lateral margin and three setae on apical (Fig. 7G ).

Description.

Body reddish brown, antennae, maxillary palpi, and tarsi slightly lighter, length 1.62 mm, maximum width 0.70 mm (Fig. 7A, B ). Setae on body yellowish, long and dense. Head long as wide (Fig. 7C ). Frons with U-shaped impression between antennal tubercles; frontal foveae absent; frontal rostrum distinct anteriorly. Vertex slightly convex; longitudinal carina present; vertexal foveae small. Eyes large with 34 facets. Maxillary palpi moderately developed; palpomeres II-III with dense tubercles; palpomere IV 0.25 mm long and about 3.30 times as long as wide, subcylindrical pseudosegment at apex. Antennae about 0.54 mm long; scapes subcylindrical, without modification, 1.83 times as long as pedicels; pedicels long as wide; antennomere III 1.70 times as long as wide; IV-VIII subequal in length; IX 0.89 times as long as wide; X 0.78 times as long as wide; XI largest, pointed at apex, 1.86 times as long as wide (Fig. 7D ). Pronotum 0.79 times as long as wide and widest at basal 3/5, lateral antebasal foveae connected by antebasal sulcus. Elytra slightly convex, 0.98 times as long as wide and widest at basal 1/3, each elytron with two basal foveae and subhumeral fovea. Legs robust; metatibiae with spine at apex (Fig. 7E , arrow). Aedeagus large, 0.36 mm long and 2.05 times as long as wide; penis fusiform and dorsal diaphragm transversely ovoid; parameres short and symmetrical, apices truncated; endophallus composed of two fine struts, asymmetrical (Fig. 7G ).

Sexual dimorphism. Unknown.

Remarks.

The adult of this species is similar to Bryaxis nemorosus Choi, Park, Lee & Park sp. nov. in the shape of antennomeres IV-XI (Figs 7D , 8F ). However, it can be distinguished by the robust setae on the body (Fig. 7A ), large eyes as long as the tempora (Fig. 9E ), a strongly tuberculate maxillary palpomere II (Fig. 9A ), protibiae with a spine at the widest point (Fig. 9C , arrow), and a simple endophallus of the male genitalia (Fig. 7G ).

Etymology.

This species is named after the type locality, Girin-myeon, Inje-gun.

Habitat.

The holotype was collected by sifting flood debris in mixed forest.

Distribution.

Korea (Inje-gun, Gangwon-do).

Figures

Figure 7. Bryaxis girinensis Choi, Park, Lee & Park, sp. nov. A dorsal habitus B ventral habitus C head D antenna E fore leg F hind leg G aedeagus. Scale bars: 1 mm (A, B); 0.1 mm (C, G); 0.5 mm (D-F).

Figure 8. Bryaxis nemorosus Choi, Park, Lee & Park, sp. nov. male (A, B, E-I), female (C, D). A, C dorsal habitus B, D ventral habitus E head F antenna G fore leg H hind leg I aedeagus. Scale bars: 1 mm (A-D); 0.1 mm (E, I); 0.5 mm (F-H).

Figure 9. Diagnostic characters of Bryaxis girinensis sp. nov. (A, C, E) and B. nemorosus sp. nov. (B, D, F). A, B maxillary palpi C, D protibiae E, F heads. Scale bars: 0.1 mm.