Alvania scabra (Philippi, 1844)
Whole Mediteranean.
Often epiphytic, the species lives in intertidal to infralittoral algal environments. Grazer and detritus feeder.
Original taxon: Rissoa scabra. Synonyms: mutabilis, oranica. The species is quite variable.
 
Original description: « Testa oblonga, conica, acuta, costato-plicata, cingulis transversis distantibus sculpta; anfractibus planis, labro intus sulcato. […] Anfractus parum convexi, costulato plicati, plicis circa 14, transversimque cingulati […] Costae in ultimo anfractu evanescunt, apex laevissimus est. Apertura ovata, dimidiam spiram vix superat. Labrum extus incrassatum, intus sulcatum est. Color albus, maculis magnis rufis ornatus. » – R. A. Philippi: Enumeratio molluscorum Siciliae, Berlin 1836-1844, via BHL.

High-spired specimen bearing a weak radial sculpture, collected in intertidal grit, Punta del Carnero, Algeciras, Andalucia, S. Spain. 2,3mm.
Philippi: « Ubi cingula costas secant, tubercula mammillaria gignuntur. »
 
Two specimens that match this description, displayed on WoRMS. Left: Arenal d’en Castell, Menorca, Islas Baleares. 2,1mm. Right: Xàbia, Comunidad Valenciana, Alicante, SE. Spain. 2,5mm. Pictures given by J. Trausel & F. Slieker, Natural History Museum Rotterdam – (CC BY-NC-SA).
Elafonisi, SW. of Kissamos, W. Crete. 1,7mm.
The variant “oranica”, smaller and less slender, from Georgioúpoli, east of Chaniá, NW. Crete. 1,8mm.
Some specimens lack tubercles. Some others have their spirals stronger than the radials, like in the group named “sculptilis”. Above, an “oranica” from 26m deep, Punta de la Mona, east of La Herradura, Granada, Andalucia. 2,35mm.
15-25m deep, Málaga, Andalucia. 2,1mm.
28m deep, Otranto, Lecce, Puglia, SE. Italy. 1,7mm.
Original pictures provided by F. Vitale (IT).
– (CC BY-NC-SA) –
Subfossil from La Mona. 2mm.
3-5m deep, Ceuta, southern Alborán. 2,2-2,3mm.
5m deep, Málaga. 2mm.
In Alvania scabra, the spiral cords II and IV start immediately after the transition protoconch-teleoconch. Also, the spiral microsculpture is almost absent in this species.

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