"Cerion iostomum moreleti, new subspecies

(Plate 11, fig. 6)

Cerion moreleti Torre ms. (in sched.)

     Description. - Shell solid, extended, reaching 36 mm. (about 1½ inches) in length, rimately perforate and strongly costate. Color a flat white to faintly mottled with dull purple or light brown. Interior of aperture a dull and pale violet to light brown. Whorls 11, very slightly convex. Spire somewhat ex­tended, last 4 whorls nearly straight-sided, early six whorls forming a slightly convex cone, the convex portion forming an angle of about 65°. Aperture subquadrate. Outer lip reflected, thickened and turned backward a little. Parietal or inner lip straight, thickened and built forward to forma strong ridge. Columella short and nearly straight. Parietal tooth centered, thickened and irregularly doubled, extending backward for less than ½ whorl. Columellar tooth small and extending within for about ½ whorl. Umbilicus rimately formed, small and shallow. Suture well defined but shallow. Sculpture: first 1½ whorls smooth and glass-like, remaining whorls with fairly strong, axial costae which number 17 to 23 on the body whorl. These costae are irregular in their development and vary in their number in different colonies. No spiral sculpture indicated.

     Types. - Holotype, Museo Poey no. 17249; paratypes, Museo Poey no. 17250, and Museum of Comparative Zoölogy no. 129129; 188542, from Punta del Este, Isle of Pines. Collected by C. de la Torre.

      Remarks. - This subspecies is in reality the dominant element in the Cerion fauna of the Isle of Pines and the Cays on the Banco de los Jardines, a group of many islands which extend some 150 kilometers to the east of the Isla of Pines. C. iostomum chaplini Wurtz from Cayo Largo is a somewhat smoother and larger from which also possesses more of the marble coloration.

     On the Isle of Pines C. iostomum moreleti extends at least from Punta del Este south and west to Caleta de Carapachibey, a dis­tance of 40 kilometers.

     Cerion chaplini moreleti complex is related to Cerion iostomum Pfeiffer of the south coast of Cuba. It differs mainly in being a little more costate and particularly in having a fewer number of the whorls forming the conic portion of the spire. Both the colu­mellar and parietal teeth in iostoma are less developed than is exhibited by chaplini and moreleti. Other than shape both species are about the same in general structural characters.

     The following are the locality records for these two forms. Cerion iostomum chaplini  Wurtz.

Cerion iostomum moreleti Clench and Aguayo.

Punta del Este, Isle of Pines (type locality)

Caleta de los Itabos, Isle of Pines

Bahia Carapachibey, Isle of Pines

Cayo Cantiles, Banco de los Jardines"  (Clench & Aguayo, 1951:73-74)