Shells tubular, slitted or not, coiled at their early whorls, moer or less uncoiled later. Operculate. The animal is sessile, the early whorls embedded in the substract.
Petalopoma Schiaparelli, 2002:
« Small to medium sized siliquariinids; teleoconchs with slit; spiral, flattened, horny operculum showin petal-like bristles, with a stalked narrow base. » – S. Schiaparelli: “Taxonomy of the family Siliquariidae (Mollusca, Caenogastropoda) in Eastern Atlantic Ocean and Mediterranean Sea: description of a new genus and a new species”, Italian Journal of Zoology vol.69, 2002, p.249. The slit is very irregular.
Tenagodus Guettard, 1770:
« The pipe is conical, rounded in a more or less perfect spiral, and which is distinguished by a longitudinal slit. » – J. E. Guettard: Mémoires sur différentes parties des Sciences et Arts, Paris 1770, “Deuxième mémoire - Classe des tuyaux marins” p.128. The slit in Tenagodus is much more regular than in Petalopoma.
