A New Quadrannulate Species of <i>Orobdella</i> (Hirudinida: Arhynchobdellida: Orobdellidae) from Kii Peninsula, Japan

A new species ofOrobdella(Hirudinida: Arhynchobdellida: Orobdellidae) from Primorye Territory, Russian Far East

“…This genus now consists of 20 species: most of them, i.e. 17 species, are distributed in the Japanese Archipelago (Nakano 2017a(Nakano , 2017b(Nakano , 2018; one species was recorded in the Korean Peninsula and adjacent islets including Tsushima Island, and two species were described in Taiwan Lai 2012, 2017). Until the 1960s, however, the genus Orobdella comprised only three species described in Japan: the quadrannulate O. whitmani Oka, 1895, the sexannulate O. ijimai Oka, 1895, and the octannulate O. octonaria Oka, 1895. In the late 1960s, quadrannulate Orobdella individuals were recorded around Vladivostok City in Primorye Territory, Russian Far East, and they were identified as O. whitmani (Ghilarov et al 1969).…”

“…Lai 2012;Nakano 2014;Nakano and Seo 2014;Nakano 2016aNakano , 2016bNakano , 2017bNakano and Lai 2017;Nakano 2018), therefore, the new species can be distinguished from the 12 quadrannulate congeners, i.e. O. angustataNakano, 2018, O. brachyepididymis Nakano, 2016a, O. esulcata Nakano, 2010, O. kanaekoikeae Nakano, 2017b, O. kawakatsuorum, O. koikei, O. masaakikuroiwai Nakano, 2014, O. meisai Nakano and Lai, 2017, O. naraharaetmagarum Nakano, 2016b tsushimensis and O. whitmani, by the following combination of characteristics (Table…”