Prostoma cisalpinum, Vialli, 1927

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 : 466

4. cisalpinum Vialli, 1927

Source. In the binomen Prostoma cisalpinum by Vialli (1927: 185).

Type locality. Province of Brescia and Province of Cremona, Lombardy, Italy ( Fig. 9 ) .

Etymology. Latin adjective, cisalpīnUs, - a, - um, “on this [the Roman or south] side of the Alps”.

Remarks. Vialli (1927) considered his P. cisalpinum to most closely resemble P. padanum Pierantoni, 1926 and distinguished the two by the body size ( P. cisalpinum being twice the length of P. padanum ), the number of eyes (6 in P. cisalpinum ; 4 in P. padanum ), the position of the cerebral-organ openings; the length of the stylet, and the number of gonads on each side of the body (27–28 in P. cisalpinum ; 10 in P. padanum ). Vialli (1927) also distinguished P. cisalpinum from P. graecense by the absence of tactile bristles at the rhynchodaeal opening and the anus. Vialli (1927) argued that P. cisalpinum is a simultaneous hermaphrodite, while P. eilhaldi was protandrous. Stiasny-Wijnhoff (1938: 226) regarded P. cisalpinum as conspecific with Prostoma eilhardi . Gibson & Moore (1976: 194) considered P. cisalpinum a nomen dubium, and Gibson (1995: 494) listed P. cisalpinum as an invalid name. Prostoma cisalpinum is herein considered synonymous with P. clepsinoides .

Volume 65 of Atti della società italiana di scienze naturali e del museo civico di storia naturale in Milano contained four issues. While Issues 1 and 2 were published in 1926, Issues 3 and 4 (which included Vialli’s article) were in 1927. Although later authors regarded the publication date of Vialli’s article, and the name cisalpinum , as 1926 ( Stiasny-Wijnhoff 1938: 230; Gibson & Moore 1976: 194; Gibson 1995: 494), the correct publication date is 1927.

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).