Resumen de Descrizione di una nuova specie di Rissoidae (Gastropoda: Prosobranchia) per le coste laziali (Mar Tirreno).
- English
Alvania claudioi n. sp. is described from Ventotene Island (Pontine Archipelago, central Tyrrhenian Sea), where it was collected at a depth of 32 m. The new taxon is compared with A. schwartziana Brusina, 1866 and A. settepassii Amati & Nofroni, 1985. The latter species is the most similar to A. claudioi n. sp. That, however, can be distinguished for the following shell characters: i) a protoconch consisting of 1.4 whorls, against the two found in A. settepassii, ii) the protoconch lacks microsculpture while A. settepassii has 10 irregular spiral threads, iii) a distinctly more rounded profile, with more convex whorls, iv) the body whorl is proportionally larger, about 71% of total height, amounting to 67% in A. settepassii, v) there are 6-7 spiral cords on the body whorl, instead of 4-5 occurring in A. settepassii, vi) the spiral cords on the base are wavy, being linear in A. settepassii, vii) there are 15-16 axial ribs on the body whorl, instead of 7-9 occurring in A.
settepassii, viii) an axial sculpture more pronounced than in A. settepassii, ix) the axial ribs are narrower than interspaces, while in A. settepassii they are of similar size, x) the outer lip is internally smooth, being lirate in A. settepassii, xii) A. claudioi n. sp. is uniformly light brown, while A. settepassii is more or less deep orange in colour, depending on the part of the shell, xiii) the size is smaller than in A. settepassii.
- italiano
Viene descritta e raffigurata una nuova specie: Alvania claudioi, rinvenuta esclusivamente, in pochi esemplari, a Ventotene (Mar Tirreno centrale), ad una profondità di circa 32 m. La nuova specie è confrontata con A. schwartziana Brusina, 1866 ed A. settepassii Amati & Nofroni, 1985; tra le due specie, A.
settepassii risulta essere quella morfologicamente più affine, anche se parecchi caratteri sia della protoconca che della teleoconca ne permettono l�agevole distinzione.
