Pterostichus (Nialoe) kamurosanus Sasakawa & Mitsuduka, 2023

Sasakawa, Koji & Mitsuduka, Yoshiji, 2023, A morphology-based revision and phylogenetic analysis of the Pterostichus macrogenys species group (Coleoptera, Carabidae) and implications for differentiation of the species group, Deutsche Entomologische Zeitschrift 70 (2), pp. 291-310 : 291

Pterostichus (Nialoe) kamurosanus Sasakawa & Mitsuduka sp. nov.

Figs 2B , 4E-H , 6B , 7A, B

Type materials.

Holotype, ♂, Ariya, alt. 403 m, Kaneyama-machi, Yamagata Prefecture, Japan (MGRS: 54SVJ49358 06377; 38.90482277°N, 140.41594335°E), 18. vi-15. vii. 2021, subterranean baited trap, Y. Mitsuduka leg., in the collection of NSMT (Fig. 2B ). Paratypes, 4♀, same data as the holotype; 2♂2♀, Kamuro Forest Road, alt. 416 m, Ariya, Kaneyama-machi, Yamagata Prefecture, subterranean baited trap, Y. Mitsuduka leg. (1♂, 15-29. ix. 2015; 1♂2♀, 5. vii-21. viii. 2017).

Description.

Body length (mm). ♂ (n = 3), BLm 14.46-15.97, 15.19 ± 0.64, BLl 13.15-14.43, 13.84 ± 0.54, BLc 12.70-13.95, 13.37 ± 0.52; ♀ (n = 6), BLm 14.19-15.08, 14.58 ± 0.46, BLl 13.10-13.63, 13.34 ± 0.27, BLc 12.60-13.21, 12.89 ± 0.31.

Head. Mandibular surface wrinkled with individual variation: short rudimentary wrinkles on both lateral sides, wrinkles on one lateral side, no wrinkles on either lateral side. Anterior-posterior length of tempora 1.7-1.8 times anterior-posterior length of eye. Surface of clypeus smooth in females, but irregular and slightly uneven in males. Antennal segment 2 with one or two setae, varying individually. Mentum tooth deeply bifid; width between paired apices apparently less than three times anterior-posterior length between level of mentum apices to level of innermost part of median notch.

Pronotum. Lateral margin arcuate for apical 3/4, only slightly sinuate for basal 1/4; anterior margin emarginated, with contour arched more strongly than curvature of apical 3/4 of lateral margin; posterior margin emarginated at median area and arcuate at lateral areas, with curvature of median area distinctively greater than that of basal 1/4 of pronotal lateral margin and that of lateral areas same or only slightly greater than basal 1/4 of pronotal lateral margin; hind angles right-angled to slightly acute. Median line disappearing near pronotal anterior margin; in holotype male, posterior end disappears in front of transverse grooved area between laterobasal impressions, while in paratype female, posterior end reached pronotal posterior end. Transverse grooved area between laterobasal impressions concave to same degree as laterobasal impressions. Surface including laterobasal impressions smooth in most specimens; in some specimens, several punctations sparsely present near posterior ends of laterobasal impressions.

Elytra. Scutellar-stria connected smoothly to stria 1 in most specimens; in some specimens, scutellar-stria disappears before connecting with stria 1, but its hypothetical extension smoothly connects to stria 1. One setigerous puncture on stria 1 at level of posterior end of scutellum. Posterior setigerous punctures on interval 3 at posterior 1/5-1/4.

Abdominal ventral sides. Sternum 7 of male very shallowly concave, with degree of concavity matching that of median area of sterna; shape of concavity transverse ellipse, but indistinct due to shallowness; posterior margin of ellipse aligns with sternum posterior margin; anterior-posterior length of concavity about 0.6 times anterior-posterior length of sternum 7; transverse, major axis of ellipse about 1.5 times that of longitudinal minor axis; area corresponding to minor axis very weakly raised, except near anterior and posterior ends.

Male genitalia. Endophallus with gonopore directed basal-ventrally; left pigmented band weakly sclerotised; right pre-apical lobe indistinct, only weakly swollen; left pre-apical lobe protrudes apically at apical part; left apical lobe short, not bifurcated (Fig. 4E-H ). Relative sizes of lobes: apical protrusion of left preapical lobe> left apical lobe apex >> right pre-apical lobe. Right paramere short, straight, with rounded apex (Fig. 6B ).

Female genitalia. Innermost part of vagina with pigmentation (Fig. 7A, B ).

Etymology.

The specific name is an adjective, derived from the Japanese noun Kamurosan, which refers to Mt. Kamuro, where the type specimens were collected and the Latin adjectival suffix - anus (m), which means, when attached to a noun, "pertaining to".

Figures

Figure 2. Habitus dorsal view of the Pterostichus macrogenys species group. A. Pterostichus namahage sp. nov. holotype male from Haraikawa; B. P. kamurosanus sp. nov. holotype male from Ariya; C. P. atsumidakensis sp. nov. holotype male from Take-no-koshi; D. P. asahinus male from Momoyake.

Figure 4. Endophallus of Pterostichus namahage sp. nov. holotype male from Haraikawa (A-D), P. kamurosanus sp. nov. holotype male from Ariya (E-H), P. atsumidakensis sp. nov. holotype male from Take-no-koshi (I-L) and P. asahinus male from Momoyake (M-P). Fully inflated endophallus in left lateral (A, E, I, M), apical (B, F, J, N), right lateral (C, G, K, O) and basal part in dorsal and apical part in ventral (D, H, L, P) views. Abbreviations: go - gonopore; lal - left apical lobe; lpb - left pigmented band; lpl - left pre-apical lobe; rpl - right pre-apical lobe.

Figure 6. Right paramere of Pterostichus namahage sp. nov. holotype male from Haraikawa (A), P. kamurosanus sp. nov. holotype male from Ariya (B), P. atsumidakensis sp. nov. holotype male from Take-no-koshi (C-E), P. asahinus male from Momoyake (F-H), P. chokaisanus male from Momoyake (I), P. chokaisanus male from Zao-chuo-kogen (J), P. kitakamisanus male from Odateminami (K, L) and P. kitakamisanus holotype male from Genbeidaira (M). Left lateral (A-C, F, I-K), right lateral (L, M), apical part in apical and basal part in ventral (D, G) and apical part in dorsal (E, H) views.

Figure 7. Genital membranous part of a Pterostichus kamurosanus sp. nov. paratype female from Ariya (A, B) and the P. atsumidakensis sp. nov. paratype female from Take-no-koshi (C, D). Dorsal (A, C) and ventral (B, D) views in everted condition of the vagina. Abbreviations: am - apophysis of the median oviduct; as - apophysis of the seminal canal; p - pigmentation on the innermost part of the vagina. Note that the two apophyses (am and as) are viewed through the membranous vagina.