Tetrastemma vittigerum, Burger, 1904

Kajihara, Hiroshi, 2025, A taxonomic revision of the freshwater monostiliferous hoplonemertean genus Prostoma Dugès, 1828 (Nemertea: Eumonostilifera): a radical solution or an over-lumping?, Zootaxa 5646 (4), pp. 451-500 : 482

22. vittigerum Bürger, 1904

Source. As a new replacement name for Oerstedia vittata Hubrecht, 1879 by Bürger (1904: 59).

Type locality. Naples , Italy .

Etymology. Adjective, vittiger, vittigera, vittigerum ; from the Latin feminine noun vitta, “band, ribbon”, and the suffix -ger, meaning “-bearing, -carrying”.

Remarks. Bürger (1904: 59) replaced Oerstedia vittata Hubrecht, 1879 with Prostoma vittigerum Bürger, 1904 to avoid secondary homonymy with Tetrastemma vittatum Verrill , because Bürger (1904) regarded the two nominal species being placed in Prostoma . If Tetrastemma vittatum Verrill, 1874 is conspecific with Cosmocephala cordiceps Jensen, 1878 —as suggested by Brunberg (1964) and Norenburg (1986) —then this taxon should be referred to as Cyanophthalma vittata ( Verrill, 1874) , instead of Cyanophthalma cordiceps ( Jensen, 1878) (cf. Gibson 1995: 527; Junoy et al. 2011: 622; Hookabe & Kajihara 2020: 268). Hubrecht’s (1879) taxon from Naples, Italy, is now Tetrastemma vittigerum ( Bürger, 1904) ( Kirsteuer 1963: 591) . Recent molecular phylogenetic analyses have suggested that specimens collected in Spain ( Kvist et al. 2014) and France ( Chernyshev et al. 2021) identified as T. vittigerum are closely related to Vieitezia luzumurbeae Junoy et al., 2010 . The two names vittigerum Bürger, 1904 and vittatum Verrill, 1874 will likely be combined respectively with Vieitezia (Chernsyshve et al. 2021) and Cyanophthalma ( Hookabe & Kajihara 2020: 268) when sufficient data become available. In that case, the secondary homonymy between vittata Hubrecht, 1879 (replaced with vittigerum Bürger, 1904 ) and vittatum Verrill, 1874 will be resolved. Even in that case, vittata Hubrecht, 1879 remains permanently invalid in accordance with Article 59.3, because the substitute name vittigerum Bürger, 1904 is currently in use.