Diaulota hokkaidona Ahn & Ôhara, 2018

[Japanese name: Hokkai-tsutsumune-umi-hanekakushi]

(Figs. 5C; 6F & I; 23A & C)

Diaulota hokkaidona Ahn & Ôhara in Song et al., 2018: 932 (original description; type locality: Hokkaido, Nemuro, Tomoshiri).

Material examined. Japan: Hokkaidô: 1 male, 1 female, 19 unsexed, Nemuro-shi, Onnetô, 24. VII. 2020, Y. Tasaku (OMNH, cYT); 22 unsexed, ditto, 18. IX. 2020, Y. Tasaku (cYT); 1 unsexed, Abashiri-shi, Komaba, 20. VI. 2022, Y. Tasaku (cYT); 13 unsexed, Nemuro-shi, Toyosato, Tôsamuporo-ko, 24. VII. 2020, Y. Tasaku (cYT); 1 unsexed, Nemuro-shi, Hamamatsu, 28. IX. 2000, M. Maruyama (KUM); 120 unsexed, Hamanaka-chô, Mochirippu, 12. IX. 1999, M. Maruyama (KUM); 1 unsexed, ditto, 17. IX. 2020, Y. Tasaku (cYT); 2 unsexed, Akkeshi-chô, Aikappu-misaki, 25. VII. 1999, M. Maruyama (KUM); 15 unsexed, Erimo-chô, near Tôyô-gyokô, 12. VII. 2018, H. Ono (cHO); 1 male, Kaminokuni-chô, Harauta, 11. IV. 2020. K. Mitsuhashi (cYT); 1 male, 3 unsexed, Samani-chô, Fuyushima, 28. III. 2020, Y. Tasaku (cYT).

Diagnosis. This species can be distinguished from other species of the genus Diaulota by the combination of the following characteristics: body small and entirely blackish; male head as large as that of female; mentum as long as wide; tarsal formula 4-4-5, apical lobe of the median lobe divided at the apex in lateral view (Fig. 6F) (see also the diagnosis of D. decipiens sp. n.).

Habitat. This species is distributed in almost all areas of Hokkaidô. In the eastern Hokkaidô (around Nemuro-shi), adults were commonly collected from rocky beaches with barnacles (Fig. 23C) and sometimes under stones in mudflats. In central and southern Hokkaidô, it is less common and adults were collected from rock crevices of rocky shores. Considering its extensive distribution in Hokkaidô, there is a possibility that this species might also be distributed in the northern Honshû.

Distribution. Japan: Hokkaidô; Russia: Kamchatka; USA: Alaska (Fig. 23A).