Tetrastemma turanicum, Fedchenko, 1872

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 : 472

24. turanicum Fedchenko, 1872

Source. In the binomen Tetrastemma turanicum by Fedchenko (1872: 101, pl. XIV, figs 1–4).

Type locality. Tashkent , Uzbekistan ( Fig. 9 ) .

Etymology. Adjective, - us, - a, - um; from Turan (a region in Central Asia, originally populated by Iranian Central Asian nomads; later, Iranians came to identify Turkic neighbours as Turanians) and the attributive adjective forming suffix - icus.

Remarks. The monostiliferous hoplonemertean proboscis and the characteristic six eyes depicted in the original illustration of the entire body ( Fedchenko 1872, pl. XIV, fig. 1), along with its occurrence in a freshwater environment, undoubtedly indicate that the nominal species Tetrastemma turanicum belongs to Prostoma . Prostoma turanicum was regarded as a nomen dubium by Gibson & Moore (1976: 194), listed as an invalid name by Gibson (1995: 498), and is now considered synonymous with P. clepsinoides .

Figures

FIGURE 9. World map showing distribution of 25 nominal species of freshwater monostiliferous hoplonemerteans indicated by boxes and respective species-group names (three subterranean species are indicated with ‘S’ in parentheses); circles, diamond, and triangles indicate localities of DNA-barcoded individuals; circles, Haplogroup 1 from the UK, Sweden (SE), Italy (IT), Macedonia (MK), Japan (JP), New Zealand (NZ), Mexico (MX), Indiana (IN), and Massachusetts (MA); diamond, Haplogroup 2 from Norway (NO); triangles, Haplogroup 3 from Sweden (SE) and California (CA).