Raphistomatidae

The Raphistomatidae is a family of Paleozoic gastropods established by Koken, 1896, whose range extends from the Upper Cambrian to Middle Permian, comprising lentuclar, turbiniform, and stepped shells with a short slit, notch, or sinus on the aperture lip that generally results in a selenizone.

J. Brooks Knight, et al ^[1] in the Treatise Part 1, 1960, included the Raphistomatidae in the Pleurotomariacea and subdived the family into four subfamilies described herein.

• Opheletinae, Knight,1956 – generally low spired with a wide umbilicus and V-shaped labral sinus ending at the periphery in a short notch that generates an obscure selenizone. U Camb - L Ord

• Raphistomatinae, Koken, 1896 – consists of shells commonly with a narrow protruding base and more or less flattened upper surface and a deep v-shaped labral sinus in most species ending in a shallow notch at the end of a peripheral selenezone. M Ord - ?L Carb

• Liospirinae, Knight,1956 – has lentiucal shells with a moderately deep V-shaped sinus resulting in a short slit that generates a convex selinizone found mostly, or entirely, on the upper side. ?L ord - M Perm

• Omospitinae, Wenz,1958 – contains gradate, that is stepped shells with a ramp and a relatively wide, shallow sinus or labral slit resulting in a selenizone just within the outer margin of the ramp. M Ord- L Jur (note, range inconsistent with that given for the family)

Jeffery, 2003,^[2] included the Raphistomatidae in the Euomphaloidea (=Euomphalacea). The subfamilies Opheletinae and Raphistomatinae are retained, but the Lionsprinae and Omospirinae have be reassigned to the Eotomaridae and Loxonematidae, respectively.

In the perspective of Bouchet and Rocroi, 2005 ^[3] the Raphistomatidae is simply included in "Basal taxa that are certainly Gastropoda" without assigning it to any higher taxa.

References