Euochin Proszynski 2018

Genus Euochin Prószyński, 2018

Euochin Prószyński, in Prószyński, Lissner & Schäfer, 2018: 55, figs 19, 20; Logunov, 2020: 525, figs 11–17; Wang & Li, 2021: 127, figs 2A–D, 3A–G; Wang & Li 2022: 93, figs 5A–D, 6A–G, 7A–G.

Type species. Euophrys atrata Song & Chai, 1992, by original designation.

Diagnosis. Modified from Logunov (2020): similar to Euophrys (s. str., see Logunov 1997) in body shape and genitalia, but can be distinguished by: (1) the more robust RTA of the male palp (e.g., Fig. 26; vs. seta-like RTA in Euophrys); (2) the presence of a long and light-colored setal tuft on the male palp (e.g., Fig. 136; vs. usually absent in Euophrys); (3) the relatively short and broad embolus (e.g., Fig. 12; vs. thread-like embolus in Euophrys); (4) the embolic disc slightly concaved centrally or highly reduced, usually slightly hidden by the apical edge of the tegulum (e.g., Figs 12, 61, see Liu et al. 2020: figs 1B–D; vs. embolic disc highly developed and exposed in Euophrys); (5) the tip of the embolus raised above the plane of the embolic disc (e.g., Fig. 12; vs. the embolus almost within the plane of embolic disc in Euophrys); (6) the relatively short copulatory duct (e.g., Fig. 14; vs. much longer copulatory duct in Euophrys); (7) the spermatheca usually visible through epigynal window, except in Euochin bamianshanensis (Liu, Wang & Peng, 2020) comb. nov. (see Liu et al. 2020: figs 2B–C), E. extraculum sp. nov. (Figs 65, 69), E. nanjiabawa sp. nov. (Figs 115, 119) and E. tianhe sp. nov. (Figs 164, 168; vs. spermatheca usually lower than the posterior edge of epigynal window in Euophrys).

Description. Small and compact jumping spiders (total length 2.58–3.86 in males; 2.93–4.28 in females). Body generally dark (especially in males), both sexes with white to light-yellow setae forming scattered stripes and patches around the body (e.g., Figs 51–54), making these spiders reminiscent of Chinattus Logunov, 1999 and Nannenus Simon, 1902. Promargin of chelicera with two teeth, retromargin with one simple tooth or compound tooth with multiple cusps (e.g., Figs 211–212). Male palps with light-colored setal tuft (e.g., Fig. 52); RSDL visible in ventral view (e.g., Fig. 10); RTA developed (e.g., Fig. 11). Female epigynal windows variable in size and position, but usually overlapping with the spermathecae in ventral view (e.g., Fig. 13); copulatory ducts short, some species with obvious accessory glands near the copulatory openings (e.g., Fig. 14); spermathecae ovoid to nearly globular (e.g., Fig. 14); fertilization ducts variable in size (e.g., Figs 84, 116).

Remark. The morphological characters of Euophrys bamianshanensis Liu, Wang & Peng, 2020 and E. longyangensis Lei & Peng, 2012 match the above diagnoses of Euochin, and both species have: (1) the long setal tuft on the male palps (Fig. 91, see Liu et al. 2020); (2) the embolus that is elevated above the plane of the embolic disc (Fig. 97, see Liu et al. 2020: fig. 1C); (3) the developed RTA; as well as (4) the relatively short copulatory duct. In addition, the female epigynal window of Euophrys longyangensis overlaps with the spermatheca in ventral view, which also fits the diagnosis of Euochin. Therefore, we transfer these two species here from Euophrys to Euochin.

Biology. Most of the known species are leaf-litter dwellers. All of the specimens examined in this study were collected by sieving leaf litter on the forest floor in mountainous areas.

Distribution. China, Micronesia (Caroline Islands), Philippines, Vietnam.