Pterostichus (Nialoe) asahinus Habu & Baba, 1960

Sasakawa, Koji & Ito, Hirotaro, 2022, The identities of two species in the Pterostichus macrogenys species group of subterranean carabid beetles (Coleoptera, Carabidae) revealed by external morphometric analysis and comparative genital morphology, Subterranean Biology 43, pp. 61-71 : 61

Pterostichus (Nialoe) asahinus Habu & Baba, 1960

Fig. 2

Pterostichus (Paralianoe) macrogenys asahinus : Habu and Baba (1960): 62 (original description), holotype ♀: "Mt. Dorokujin, Mts. Asahi, Niigata Pref." [Miomote, Mt. Dôrokujinpô, Murakami-shi, Niigata Prefecture, Japan]; Habu and Baba (1972): 19.

Pterostichus (Paralianoe) asahinus : Habu (1977): 14 (part).

Pterostichus macrogenys : Tanaka (1985): 114 (part?).

Pterostichus (Nialoe) asahinus : Bousquet (2017): 724.

Pterostichus (Nialoe) falcispinus : Sasakawa (2005): 75 (original description), holotype ♂: "Cave Ishikiri, Nakajo-Machi, N-Echigo" [Ishikiri Cave, Mt. Ishikiriyama, Haguro, Tainai-shi, Niigata Prefecture, Japan]; Bousquet (2017): 724; Sasakawa et al. (2020): 7. Syn. nov.

Specimen examined.

1♂, Miomote, alt. 276 m, on the right bank of Miomotegawa River, Murakami-shi, Niigata Prefecture, Japan (38.273211°N, 139.779922°E), 12.vi.-17.vii.2021, Hirotarô Itô leg., in the collection of HI.

Notes.

Sasakawa et al. (2020) suggested that P. asahinus and P. falcispinus might be conspecific. However, this hypothesis remained untested because males from the type locality of P. asahinus have not been examined. The male specimen examined here was obtained from a valley southwest of Mt. Dôrokujinpô, which can virtually be regarded as the type locality (Fig. 1 ). The structures of the endophallus and right paramere of this specimen are identical to those of the eastern type of P. falcispinus in Sasakawa et al. (2020). Its body length is intermediate between that of the eastern and western types of P. falcispinus as follows: body length from mandible apices to elytral end (BLm) 16.32 mm, that from anterior margin of labrum (BLl) 14.72 mm, and that from clypeal apex (BLc) 14.26 mm. Based on these results, we regard P. asahinus and P. falcispinus as conspecific. The results of the discriminant analysis support this conclusion. The P. asahinus holotype was classified in this newly defined P. asahinus in the discriminant function analysis, and was within the area of P. asahinus on the scatterplot of the first two canonical variates (Fig. 3 ).

Figures

Figure 1. Distribution of the Pterostichus macrogenys species group in northern Chubu, northern Kanto, and southern Tohoku Districts, Honshu, based on specimens with unambiguous identities, modified from Sasakawa et al. (2020) and Sato (2021) 1 P. chokaisanus Sasakawa, 2009 2 P. kurikomasanus Sasakawa, 2005 3 P. asahinus Habu and Baba, 1960 4 P. takadateyamanus Sasakawa, 2009 5 P. adatarasanus Sasakawa, 2005 6 P. gassanus Sasakawa, 2009 7 P. shinbodakensis Sasakawa & Ito, 2017 8 P. awashimaensis sp. nov. 9 P. iwakiensis Sasakawa, 2009 10 P. eboshiyamanus Sasakawa, 2009 11 P. tateishiyamanus Sasakawa & Ito, 2017 12 P. monolineatus Sasakawa, Mitsuduka, & Ito, 2020 13 P. yamizosanus Sasakawa, 2005 14 P. yahikosanus Sasakawa, 2009 15 P. ohsawacavus Sasakawa, 2005 16 P. sumondakensis Sasakawa, 2005 17 P. isolatus Sasakawa, 2005 18 P. nakamiyorinus Morita, Ohkawa & Kurihara, 2013 19 P. momuranus Morita, Ohkawa & Kurihara, 2013 20 P. macrogenys Bates, 1883 21 P. nagasawai Ito & Ogai, 2015. Red letters denote the type localities of each species. The blue letter indicates where the male specimen of P. asahinus newly examined here was collected.

Figure 2. Pterostichus asahinus male from Miomote, on the right bank of the Miomotegawa River A habitus dorsal view B-E Endophallus left lateral (B) ventral (C) right lateral (D) and dorsal (E) views F-H right paramere left lateral (F) apical (G) and dorsal (H) views. go, gonopore; lal, left apical lobe; lpl, left preapical lobe; rpl, right preapical lobe.

Figure 3. Scatterplot of the first two canonical variates obtained from the discriminant analysis of four measurements of the female pronotum.