Prismognathus dauricus (Motschulsky, 1860)

(Figs. 21, 98, 125, 137, 179, 207, 234)

Metopodontus dauricus Motschulsky, 1860: 137 [type locality: “la notre se rencontre au sud de la Daourie, et sur les bord du fl. Amour, aux environs du fort Mariinsk”], plate 9, Fig. 11, female.

Prismognathus subaeneus Motschulsky, 1860: 138 [type locality: “bords du fl. Amour”], plate 9, Fig. 12, male; Didier & Séguy, 1953: 127. Synonym.

Cyclorasis jekelii Parry, 1864: 41 –42 [type locality: “Chowsan, Corea ”], plate 9, Fig. 4, male head. Synonymized by Benesh (1960).

Prismognathus dauricus: Benesh 1960: 56, synonymic list; Mizunuma & Nagai, 1994: 238, plate 51, Fig. 235, males and female; Wan et al. 2007: Figs. 16–19, males and female; Figs. 23–24, male genitalia; Fig. 25, female genitalia; Kim & Kim 2010: 72 -76, locality details in Korea; Fig. 12 p, male and female; Fujita 2010: 164, plate 99, Fig. 488, males and female from Tsushima Island and northern Korea.

Prismognathus davidis: Didier & Séguy 1952: partim [plate 91, Figs. 1–2]. Misidentification.

Material examined. CHINA: Liaoning: 12 3, 8 ƤƤ, Dan-dong City, Laogugou, 26.VII.-11.VIII.2008, H.-C. Shan leg.; 2 3, 2 ƤƤ (CHH, CYXW), Shenyang, no detailed data. Jilin: 2 ƤƤ (IEAS), Changbaishan, Erdaokouhe, 14.VIII.1984, Z.-Y. Liu leg. KOREA: 6 3, 4 ƤƤ, Mt. Dulunsan, VIII.2009.

Identification. This species is distributed in the Russian part of Amur region and in northeastern China; there are no other species of Prismognathus living in the same area.

Diagnosis. The large and medium-size males of P. dauricus are characterized by the absence of the subbasal teeth along the dorsal ridge of the mandible. The small males of P. dauricus are not easy to separate from those of P. klapperichi and P. davidis (apart for the different geographic distribution) unless the genitalia are examined. The females of P. dauricus are indistinguishable in external characters from those of the similar species, especially P. davidis . To identify the female of P. dauricus, a dissection is always needed. For more details see the keys below.

Distribution. Liaoning; Russia (eastern Siberia), Korea, Mongolia, Japan (Tsushima Island only).