Leptoplectus, Casey, 1908

Byeon, Ui-Joung, Jang, Min-Sang, Park, Sun-Jae, Kim, A-Young & Park, Jong-Seok, 2021, Review of Korean Species of the Genus Leptoplectus Casey (Coleoptera: Staphylinidae: Pselaphinae: Euplectitae) with Description of a New Species, The Coleopterists Bulletin 75 (3), pp. 689-694 : 690-691

Genus LEPTOPlECTUS Casey, 1908

Leptoplectus Casey 1908: 266 ; Schülke and

Smetana 2015: 382; Ahn et al. 2017: 6. Grammoplectus Jeannel 1950: 100 .

Type Species. Euplectus pertenuis Casey, 1884 .

Diagnosis. Head subquadrate, wider than long with vertexal foveae ( Figs. 1C , 4C ); antennomeres 9–10 transverse ( Figs. 2D , 5E ); each elytron rectangular, longer than wide, with distinct subhumeral elytral foveae and three or four basal elytral foveae ( Figs. 2A , 5A , right arrow); metaventrite with medial metaventrital and lateral mesocoxal foveae ( Fig. 5D ); abdominal tergites IV–V with discal carinae and mediobasal foveae ( Figs. 2B , 5B , arrows), VII longest ( Figs. 1A , 4A ); abdominal sternite IV with mediobasal and basolateral foveae ( Figs. 2C , 5C , arrows); tarsal formula 3-3-3, all tibiae with small spines posteriorly ( Figs. 2E–G , 5F ).

Distribution. Palearctic, Nearctic, Afrotropical, Oriental.

Comments. The genus Leptoplectus is morphologically similar to Euplectus . However, Leptoplectus has lateral metaventrital foveae present and anterior margin of labrum with one or two emarginations, while Euplectus has lateral metaventrital foveae absent and anterior margin of labrum round- ed or straight ( Chandler 2000; Jałoszyński and Nomura 2021). Ventrite IX of males, but not of females, is divided vertically ( Fig. 1B , arrow). Specimens have been collected by sifting wet leaf litter and soil.

KEY TO KOREAN SPECIES OF THE GENUS LEPTOPLECTUS CASEY

1. Each elytron with four basal elytral foveae ( Fig. 2A , left arrow); metatrochanter without spine ( Fig. 2G , arrow) ..… L. illEx KurbatoV

1′. Each elytron with three basal elytral foveae ( Fig. 5A , left arrow) ................................… 2

2. Metatrochanter with spine ( Fig. 5F , arrow); median lobe of male genitalia divided into two branches, phallobase asymmetrical ( Fig. 5G ) ........…............. L. kOrEanUS Byeon, Jang, Park, Kim, and Park , new species

2′. Median lobe of male genitalia not divided, phallobase symmetrical ( Löbl 1975: figs. 4–5) ..................................… L. vaganS Löbl

Figures

Fig. 1. Leptoplectus illex. A) Dorsal male habitus, B) Ventral male habitus, C) Dorsal head, D) Ventral prosternum. Scale bars = 1 mm (A–B), 0.1 mm (C–D).

Fig. 4. Leptoplectus koreanus, new species. A) Dorsal male habitus, B) Ventral male habitus, C) Dorsal head, D) Ventral prosternum. Scale bars = 1 mm (A–B), 0.1 mm (C–D).

Fig. 2. Leptoplectus illex. A) Dorsal elytra, B) Abdominal tergites IV–V, C) Abdominal sternites III–IV, D) Antenna, E) Fore leg, F) Middle leg, G) Hind leg. Scale bars = 0.1 mm.

Fig. 5. Leptoplectus koreanus, new species. A) Dorsal elytra, B) Abdominal tergites IV–V, C) Abdominal sternites III–V, D) Ventral meso- and metaventrite, E) Antenna, F) Hind leg, G) Lateral median lobe of male genitalia. Scale bars = 0.1 mm.