Alvania skylla Tisselli & Micali, 2023
Western and central Mediterranean.
Low infralittoral to lower photic zone. Probably detritus feeder.
 
Often confused with Monterosato’s Alvania subareolata, from which it differs morphologically by many characteristics: axial ribs stronger and fewer, strictly orthocline and not slightly sinuous; spiral cords 2 or rarely 3 instead of always 3 in subareolata; the crossings are markedly tuberculate, giving the whorls a keeled appearance; the microsculpture also is much thinner. The protoconch is adorned with numerous microgranules that tend to be arranged in six rows, especially near the transition with the teleoconch, while these granules are randomly scattered in subareolata.

Above: colour variation in the species. Notice the rows of granules on the protoconch. Original pictures provided by A. Nappo (IT) – (CC BY-NC-SA).
Uniformly coloured specimen.
35-50m deep, Ceuta. 2,5mm.
A specimen from Češinica islet, Lastovnjaci archipelago, Dubrovnik-neretva Comitat, S. Croatia. 1,95mm. Original pictures provided by A. Petani (HR) – (CC BY-NC-SA).
80m deep, Grotta Azzurra, Capri, Campania, SW. Italy. 2mm.
One of the simplest sculptures in the genus, making the species easily identifiable even when subfossil.

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