The shell in the photo above (from G. & Ph. Poppe) belongs to Raphitoma histrix (Bellardi 1847)*, a small marine gastropod (the shell shown is just over 6 mm long). Raphitoma histrix was first described as a fossil from the Pliocene of north-western Italy, but the name has also been used for Recent shells from the Mediterranean and western Africa. Rolán et al. (1998) implied (but did not state) that the identity of the modern specimens could do with a double-check. Raphitoma histrix is found in soft-bottomed, reasonably calm waters.
*There has been a bit of confusion over the exact name for this species. Many authors have referred to it as 'Raphitoma hystrix (Cristofori & Jan 1832)'. However, as noted by Pusateri et al. (2012), Cristofori & Jan's name was a nomen nudum (meaning that it lacked an accompanying description), making it not validly published. The name was not validated until it was used by Bellardi (1847), who used the spelling 'histrix'.
Raphitoma histrix is the type species of the genus Raphitoma, which is in turn the type genus of the subfamily Raphitominae. Past authors have classified this genus within the family Turridae, and the Raphitominae broadly corresponds with the group that has often been called the 'Daphnellinae' (other 'turrids' have been featured on this site before: Comitas, Antiplanes, Kuroshioturris, Asperdaphne and Paradrillia). However, with the recognition that the old 'Turridae' was largely just a dumping ground for less differentiated members of the superfamily Conoidea, the Raphitominae is now usually treated as part of the Conidae, and so a member of the same family as the cone shells. Like other members of this family, including other species of Raphitoma, R. histrix is probably a predator, possibly feeding on other marine invertebrates such as worms.
Pusateri, F., R. Giannuzzi-Savelli & M. Oliverio. 2012. Revisione delle Raphitomidae mediterranee 1: su Raphitoma contigua (Monterosato, 1884) e Raphitoma spadiana n. sp., specie sorelle (Gastropoda, Conoidea). Sociedad Espanola de Malacologia—Iberus 30 (1): 41-52.
Rolán, E., J. Otero-Schmitt & F. Fernandes. 1998. The family Turridae s.l. (Mollusca, Gastropoda) in Angola (West Africa), 1. Subfamily Daphnellinae. Sociedad Espanola de Malacologia—Iberus 16 (1): 95-118.