Exploring the basal topology of the heteronemertean tree of life: establishment of a new family, along with turbotaxonomy of Valenciniidae (Nemertea: Pilidiophora: Heteronemertea) Author Kajihara, Hiroshi Author Abukawa, Shushi Author Chernyshev, Alexei V. text Zoological Journal of the Linnean Society 2022 196 503 548 journal article 133817 10.1093/zoolinnean/zlac015 372f8265-c53c-43fa-9448-07d5a58d311f 0024-4082 7037958 78C56409-FCCF-4116-8D8C-FF66B247C56C BASEODISCUS NIPPONENSIS ( HUBRECHT, 1887 ) ( FIG. 3N ) Eupolia nipponensis Hubrecht, 1887: 14–15 , pl. I, figs4, 5, 10, pl. VII, figs 6, 11, 12 (Sagami Bay, Japan ). Baseodiscus nipponensis : Bürger, 1904: 84 . Baseodiscus nipponicus ( lapsus calami ): Kajihara, 2017: 423 (Sagami Bay, Japan ). Material examined: ICHUM 6338 , extracted DNA and remaining body preserved in 99% EtOH; 19 February 2014 , dredged from Sagami Bay (between 35°05′57″N , 139°34′52″E , 249 m depth and 35°05′47″N, 139°34′05″E, 309 m depth ), Japan , station 2 of the 2 nd JAMBIO Coastal Organism Joint Survey ( Nakano et al. , 2015 ), collected by H. Kajihara. Sequences: From ICHUM 6338 : LC178630 , 28S (1121 bp); LC178677 , 16S (505 bp) . Description: Body length 3.5 cm, width 1 mm ; dorsally reddish brown, ventrally white; eyes present; cephalic furrow encircling head; secondary furrows present ( Fig. 3N ). Distribution: So far known only from Sagami Bay, Japan ( Hubrecht, 1887 ; Kajihara, 2017 ; present study). Remarks: Hubrecht’s (1887) material of Eupolia nipponensis was dredged from green mud at a depth of 345 fathoms (about 640 m ) on 12 May 1875 by HMS Challenger in Sagami Bay ( 35°11′00″N , 139°28′00″E ). Three body fragments were illustrated by Hubrecht (1887 : pl. I, figs 4, 5, 10). Although nothing is mentioned about the size and coloration of these specimens, they were probably small (probably a few centimetres) and devoid of colour pattern, although Hubrecht (1887 : fig. 5) may have illustrated the dorsal pigmentation that is also seen in our specimen (ICHUM 6338) from a depth of 309 m in Sagami Bay. Judging from the body size, our specimen (3.5 cm long) was probably a juvenile.