Alvania tessellata
Schwartz in Weinkauff, 1868
Mediterranean, from Algeria to at least the Adriatic.
Detritus feeder.
 
Close to pagodula and spinosa, but there is no published figure of this species. J. J.  van Aarsten, who studied a specimen from the British Museum labelled “Rissoa tessellata (Schw.) = Philippiana Jeffr. = pagodula BDD. Algier, M. Joly.”, describes the shell as being much larger than usual spinosa and having a more pronounced sculpture (Basteria 40, 1976).

3m deep, Pakoštane, Zadar Comitat, Dalmatia, Croatia. 2,2mm.
« Testa solida flavido-alba, languida, conico-oblonga; spira gracilis acuminata; anfractus septum valde convexi, carinati sutura profunde divisi, tres primi embryonales unicarinati, ultimus cingulis elevalis tribus (penultimus duobus) costique longitudinalibus 11-12 rectis, abbreviatis distincte clathratus, in basi cingulis duobus laevibus instructus; apertura rotundata; labrum subsinuatum, extus varice laevi incrassato ornatum, intus laevigatum. » – Schwarz in H. C. Weinkauff: Die Conchylien des Mittelmeeres, ihre geographische und geologisches Verbreitung Bd.2, Cassel 1868, p.311.

Same spot. 2mm.
The sculpture and the microsculpture are coarse, on the protoconch as well as on the teleoconch.

35-50m deep, Málaga, Andalucia, S. Spain. 3,5mm.

— back to Rissoidae —