Leptoplectus illex, KurbatoV, 1992

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 : 691-692

LEPTOPlECTUS illEx KurbatoV, 1992 ( Figs. 1–3 , 6 )

Leptoplectus illex Kurbatov 1992: 43 ; Schülke and Smetana 2015: 382.

Material Examined. 1♂ ( CBNUIC), Gangwon Prov., Samcheok-si, Singi-myeon, Hwanseon-ro , 172 m, 37°22′22.60˝N, 129°03′28.50˝E, 23 VIII 2018, Y.-J. Choi, Sifting leaf litter ; 1♂ ( CBNUIC), Gyeongnam Prov., Geoje-si, Jangmok-myeon, Geojebuk-ro , 80 m, 35°01′27.0′′N, 128°41′59.0′′E, 22 II 2019, J.-S. Park, Sifting leaf & deadwood litter ; 1♂ ( CBNUIC), Chungbuk Prov., Goesangun, Cheongjeon-myeon, Songmyeon-ri , 254 m, 36°39′48.2′′N, 127°50′09.0′′E, 19 IX 2019, J.-W. Kang, Y.-J. Choi, S.-H. Choi, Sifting leaf & deadwood litter ; 1♂ (specimen dissected and mounted in euparal on glass slide, CBNUIC), Gangwon Prov., Hongcheon-gun, Hwachon-myeon, Garakjaero , 240 m, 37°42′26.0′′N, 127°54′43.0′′E, 05 V 2019, J.-S. Park, Sifting leaf litter .

Diagnosis. This species can be distinguished from other Korean Leptoplectus species by the following combination of characters: metatrochanter without spine ( Fig. 2G , arrow); each elytron with four basal elytral foveae ( Fig. 2A ); median lobe of male genitalia asymmetrical with two branches, right branch curved posteriorly ( Figs. 3A–B ).

Redescription. Body length 1.4–1.6 mm. Body color reddish-brown ( Figs. 1A–B ). Head. Head subquadrate with U-shaped vertexal sulcus and distinct vertexal foveae ( Fig. 1C ). Antennomere 1 elongate, 2–4 subquadrate, 5–9 transverse, 10 trapezoid, 11 largest and flattened ( Fig. 2D ). Maxillary palpomere I elongate and three times as long as II, II smallest and about as long as wide, III largest and bulbous with minute segment apically ( Figs. 3E–F ). Labrum with approximately twelve setae, anterior margin with deep U-shaped emargination ( Figs. 3C–D ). Thorax. Pronotum with distinct lateral antebasal foveae and transverse antebasal sulcus. Prosternum with anteroprosternal foveae ( Fig. 1D ). Metaventrite with medial metaventrital foveae, lateral mesoventrital foveae, and median striae. Elytra with distinct subhumeral foveae ( Fig. 2A ). Elytra same length or slightly shorter than visible abdomen. Metatrochanter without spine. Apex of all tibiae setiferous ( Figs. 2E–G ). Abdomen. Tergite VII longest ( Fig. 1A ), IV–V with discal carinae and mediobasal foveae ( Fig. 2B , arrows). Abdominal sternite IV with mediobasal foveae ( Fig. 2C , left arrow), IV– VII with basolateral foveae ( Fig. 2C , right arrow). Aedeagus. Phallobase of male genitalia oval and symmetric ( Figs. 3A–B ).

Distribution. Russia (Far East), Korea ( Fig. 6 , circles).

Habitat. The species was collected during January through September by sifting leaf litter and dead wood in a wet forest.

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. 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. 3. Leptoplectus illex. A–B) Dorsal median lobe of male genitalia, C–D) Dorsal labrum, E–F) Dorsal maxillary palp. Scale bars = 0.1 mm.

Fig. 6. Collection sites for Leptoplectus in Korea. L. illex, circles; L.koreanus, new species, square; L.vagans, pentagon.