Alvania testae (Aradas & Maggiore, 1844)
Norway & Sweden to Mediterranean, NW. Africa (Agadir).
Detritus feeder on the low infralittoral (north) down to 2400m. In Mediterranean, it is more commonly found in 100-800m. Original taxon: Rissoa testae.
 
« Testa parva, ovato-conoidea, anfractibus 5-6 convexis, suturis profundis divisis, longitudinaliter oblique costulatis, eleganter transverse sulcatis, et superne laeviter planulatis; apertura sub-ovata, superius subangulata; labro incrassato extus marginato. […] We believed it was our duty to dedicate the species described to the honourable Mr. Domenico Testa […] for having received it as his discovery… » – Aradas & Maggiore: “Catalogo ragionato delle conchiglie viventi e fossili di Sicilia…”, Atti della Accademia gioenia di scienze naturali in Catania vol. XX, Catania 1843 (1844), via BHL.

85m deep, Bozcaada island, Çanakkale province, W. Marmara, NW. Turkey. 2,5mm.
Synonym: Rissoa abyssicola Forbes. Protoconch multispiral. The transition with the teleoconch is marked.
Rissoa abyssicola Forbes, in Forbes & Hanley: A history of British Mollusca and their shells vol. I, London 1853, via BHL.
 
« It floats like its congeners, and suspends itself in the water by a single byssal thread. Mediterranean specimens are smaller than ours, and have rather stronger sculpture. » – J. G. Jeffreys: British Conchology vol. IV, London 1847, p.20.
A young shell with a well preserved protoconch, which allowed to obtain rather precise views of the prosocline ribs that cover the lower part. 80m deep, hvarski kanal, Split-Dalmatia Comitat, S. Croatia. 1,95mm. The species is common in the channel.

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