Ecnomus yamashironis Tsuda 1942

Kuhara, Naotoshi, 2016, Revision of Japanese species of the genus Ecnomus McLachlan (Trichoptera: Ecnomidae), with descriptions of two new species, Zootaxa 4114 (5), pp. 561-571 : 565-566

Ecnomus yamashironis Tsuda 1942

( Figs. 3 A–D, 6)

Ecnomus yamashironis Tsuda 1942: 267 –268, fig. 26 [Type locality: Japan, Honshû, Shiga and Kyôto]. (Type not seen.)

Diagnosis. This species can be distinguished from the other Japanese species by the elongate and straight inferior appendages in the male and the trilobed posterior margin of the ventromesal plate of segment VII in the female.

In the original description, Tsuda (1942) described and illustrated the male genitalia of this species. In addition, Li & Morse (1997) and Arefina (2003) re-described the male and female genitalia based on Chinese and Far East Russian specimens, respectively. Illustrations of the male ( Figs. 3 A–C) and female ( Fig. 3 D) genitalia of the Japanese specimens are provided.

Specimens examined. [Hokkaidô] Sôya: 2 females, Sarufutsu-mura, Narita-gawa, Kaede-bashi, 31.vii.2007, NK; 1 female, Sarufutsu-mura, Nigori-kawa, Wakakusa-bashi, 1.viii.2007, TI; 19 males, 5 females, Sarufutsumura, Asajino, outlet of Kamuito-numa, 31.vii.2007, NK; 7 males, Sarufutsu-mura, Sarufutsu-2-gôsen-gawa, Shôbu-bashi, 8.vii.2007, NK & TI; 24 males, 18 females, ibid, 31.vii.2007, NK & TI; 2 males, 1 female, Sarufutsumura, tributary of Sarufutsu-gawa, 15.vii.2006, NK; 15 males, 4 females, Toyotomi-chô, Sarobetsu-gawa, Kaiunbashi, 16.vii.2006, NK; 1 female, Wakkanai-shi, Masuhoro-gawa, 20.viii.1997, TI & AO. Rumoi: 21 males, 53 females, Rumoi-shi, Ôwada, el. 9-10 m, 2.viii.2015, NK. Ishikari: 1 male, Chitose-shi, Neshikoshi, Chitose-gawa, 20.viii.1997, NK; 1 male, Chitose-shi, Bibi, Chitose-ko, 28.vii.2007, TI. [Honshû] Ibaraki: 1 male, 2 females, Ishige-machi, Kinu-gawa, 16.vii.1997, K. Tojo; 4 males, Yasato-machi, Gorindô, Koise-gawa, 16.v.1998, N. Kawase. Shizuoka: 3 males, 3 females, Shimizu-chô, Kakita-gawa, 27.v.2001, T. Nozaki, & K. Tanida. Mie: 2 males, 1 female, Kameyama-shi, pond in Sekichô-washiyama, 5.ix.2013, TI; 6 males, 8 females, ibid, 10.ix.2014, TI. Shimane: 1 male, 3 females, Ôda-shi, Sambe, Ukinuno-no-ike, 5.viii.2001, AO.

Distribution. Japan (Hokkaidô, Honshû), Korea, China, Russian Far East.

Habitat. Many specimens shown above were collected along slow-flowing, lowland rivers, suggesting that the larvae may prefer lotic waters. According to Nishino & Tanida (1992), however, adults can be collected also along shorelines of Lake Biwa-ko in central Honshû.

Figures

FIGURE 3. Ecnomus yamashironis Tsuda (Honshû, Shizuoka, Kakida-gawa). 3 A – 3 C, male genitalia: 3 A, left lateral; 3 B, dorsal; 3 C, ventral; 3 D, female genitalia, ventral.