Rissoa costeiensis Kowalke and Harzhauser, 2004

TĂMAȘ A., TĂMAȘ D. M. & POPA M. V., 2013, Badenian Small Gastropods From Lăpugiu De Sus (Făget Basin, Romania). Rissoidae Family, Acta Palaeontologica Romaniae 9 (1), pp. 57-66 : 58-60

Rissoa costeiensis Kowalke and Harzhauser, 2004

Fig. 2c

2004 Rissoa costeiensis sp. nov. - Kowalke and Harzhauser, p. 117, fig. 5B

Material: 12 specimens, 10 from L5, one from Lp2 and one from Lp10 (one specimen PMBBU 23852 ) Description: Conical, elongated shell reaching up to 3 mm in height and 1.5 mm in width, with six whorls. The protoconch includes three convex whorls. The teleoconch shows convex whorls with incised suture and ornamentation consisting of prominent axial ribs with higher convexity in their median part. Fine spiral threads noticeable in the interspaces between the axial ribs, more prominent in the inferior half of the whorl. The last whorl is about 60% from the total height of the shell. It is ornamented with 16 axial ribs intersected by 12 spiral threads. Toward the base, 6-8 additional spiral threads are visible. Oval aperture, the inner lip partly covers the umbilicus, while the external one is thickened because of the varix .

Distribution: identified in Romania ( Kowalke and Harzhauser, 2004).

Figures

Fig. 2 - a Rissoa acuticosta (Sacco, 1895). b Rissoa clotho Hörnes, 1856. c Rissoa costeiensis Kowalke & Harzhauser, 2004. d Alvania (Alvania) oceani (d'Orbigny, 1852). e Alvania (Alvania) productilis Boettger, 1906. f Alvania (Alvania) perregularis (Sacco, 1895). g Alvania (Alvania) ampulla (Eichwald, 1853). h Alvania (Alvania) helenae Boettger, 1901. i Alvania (Alvania) transiens (Sacco, 1895).