Pterostichus (Micronialoe) bifoveolatus Park, Kwon & Lafer, 1996

Kim, Dooyoung & Suh, Sang Jae, 2024, Review of the ground beetle subgenus Micronialoe from Korea, with a description of a new species (Coleoptera: Carabidae: Pterostichus), Zootaxa 5471 (4), pp. 451-464 : 458-459

Pterostichus (Micronialoe) bifoveolatus Park, Kwon & Lafer, 1996

Korean name: Ī마길쭉먼지벌레

( Figure 7 )

Pterostichus (Micronialoe) bifoveolatus Park, Kwon & Lafer, 1996: 74 .

Specimen examined. Korea • 1♂; Gyeongsangnam-do, Sancheong-gun, Samjang-myeon, Honggye-ri , Bammeorijae pass; 35°22'46.7"N 127°51'13.7"E; alt. ca 530 m; 5 Aug. 2022; Dooyoung Kim leg.; KNU .

Diagnosis. This species is easily distinguished from known species of the subgenus by: i) posteromedian area of male sternite VII not rugose and asymmetrically depressed, ii) median lobe of aedeagus with rounded apex in dorsal view, and iii) internal sac of aedeagus with two sclerotized areas. Other significant characters are as follows.

Pronotum slightly sinuate on lateral margin before basal angle; with two pairs of basal foveae. Posteromedian area of male sternite VII with microsculpture consisting of irregular transverse meshes. Median lobe of aedeagus stout, left lateral margin below apical orifice distinctly convex; ventral carina well developed, widely rounded; sclerotized areas in internal sac consist of followings: i) C-shaped sclerite (CS) on median area and ii) wide triangular shaped ventral sclerite (VS) on apical area.

This species may be closely allied to P. (M.) kaniei Morita, 2005 , based on their common genital characters: i) median lobe of aedeagus stout, ii) apex moderately rounded in dorsal view, iii) left lateral margin below apical orifice convex, and iv) ventral carina widely rounded.

Redescription. Body length: 7.8–8.7 mm, width: 2.8–3.4 mm.

Coloration reddish black and shiny, elytra slightly iridescent; antennae, legs, and lateral margin of both pronotum and elytra reddish brown; palpi yellowish brown, with apices distinctly paler; ventral side reddish brown ( Figs 7A, B ).

Head ( Fig. 7C ). Eye weakly convex; tempus well developed, moderately convex, as long as eye; frontal impression deep, moderately curved toward anterior supraorbital pore.

Pronotum ( Fig. 7 ) widest near 2/5 from apex; apical angle narrowly rounded, slightly protruded anteriorly; lateral margin slightly sinuate before basal angle; basal angle obtuse; with two pairs of basal foveae; inner foveae deep and distinct, linear, almost parallel, with distinct punctures; outer foveae almost linear, slightly tilted outward; basal surface almost smooth medially; area between inner fovea and outer fovea with or without distinct punctures. PW /HW = 1.61 (1.59 in holotype) , PW / PL = 1.11 (1.20 in holotype) ; PW /PbW = 1.19 (1.16 in holotype) ; PW /PaW = 1.46 (1.41 in holotype) ; PbW/PaW = 1.23 (1.21 in holotype).

Elytra widest before 2/5 from base; striae deep, punctate from base to basal half; marginal umbilicate series composed of three groups, humeral group with 5 pores, medial group with 1 pore, and apical group with 7 or 8 pores. EW/ PW = 1.19 (1.19 in holotype) ; EL/ PL = 2.02 (2.26 in holotype) ; EL/EW = 1.55 (1.58 in holotype).

Ventral side ( Figs 7B, 7D ). Posteromedian area of male sternite VII ( Fig. 7D ) asymmetrically depressed, not rugose, with microsculpture consisting of irregular transverse meshes.

Male genitalia ( Figs 7E–K ). Median lobe of aedeagus ( Figs 7E–I ) stout, distinctly curved in lateral view, almost linear in dorsal view; left lateral margin below apical orifice distinctly convex; apical orifice bent to left; terminal lamella very short; apex moderately rounded in dorsal view; ventral carina well developed, widely rounded, clearly visible in right dorsolateral view; internal sac with two sclerotized areas: i) C-shaped sclerite (CS) on median area and ii) wide triangular shaped ventral sclerite (VS) on apical area; left paramere ( Fig. 7J ) wide; right paramere ( Fig. 7K ) slender, distinctly curved, ventral margin forming obtuse angle, dorsal margin widely rounded.

Type locality. Mt. Jirisan , Gyeongsangnam-do, Korea .

Figures

FIGURE 7. Male habitus and genitalia of Pterostichus (Micronialoe) bifoveolatus Park, Kwon & Lafer. (A) habitus, dorsal view; (B) habitus, ventral view; (C) head and pronotum, dorsal view; (D) sternite VII; (E) median lobe of aedeagus, right lateral view; (F) median lobe of aedeagus, dorsolateral view; (G) median lobe of aedeagus, dorsal view; (H) median lobe of aedeagus, ventral view; (I) median lobe of aedeagus, left lateral view; (J) left paramere; (K) right paramere. Scale bars: 1 mm A–C; 0.5 mm D; 0.3 mm E–I; 0.2 mm J–K. Abbreviations: VS: ventral sclerite; CS: C-shaped sclerite; C: ventral carina.