Conus drezi (Hoerle, 1976)

 

 

Diagnosis (1):

 

Spire moderately high, flat-sided in outline; shoulder acute; base constricted. Nucleus unknown, nine teleoconch whorls remaining. Sides of first three post-nuclear whorls with coarse axial costae, costae less strong on later whorls, entirely absent by seventh whorl. Summits of early whorls flat, later ones slightly concave. Whorls ornamented with strong, moderately opisthocyrt growth lines and spiral striae, striae confined to adapical half of whorl summits, thus forming a broad, smooth, flat rim on each shoulder. Sutures distinct, lightly adpressed ; outer lip with a moderate forward arch; anal fasciole concave. Basal sculpture consisting of twelve flat spiral bands separated by narrower, deep, incrementally ornamented interspaces, the six adapical bands medially grooved, the remainder crowded. Columella straight.

 

Dimensions of holotype: height 30.0 mm (incomplete) , diameter 16.3 mm.

Holotype: USNM 220123.

Type locality: TU 69A, first ravine upstream from Shell Bluff, Shoal River (NW ¼  Sec. 4, T3N, R21 W), about 3% miles north of Mossyhead, Walton County, Florida.

Occurrence: Shoal River Formation, Florida; middle Miocene.

 

Figured specimen: USNM 220123 (holotype).

 

Discussion: C. drezi, based on a single specimen, is unlike any other Conus species in the Alum Bluff Group. The flat band bordering the shoulders of the spire whorls is the most outstanding diagnostic feature. This characteristic has not been seen by the writer on any other specimens, fossil or Recent. An unnamed species in the middle Pliocene Pinecrest beds of south Florida (see Akers, 1974, p. 119) and the Recent Caribbean C. stimpsoni Dall have similar early whorls and concave anal fascioles but both lack the shoulder band. The color pattern, seen with the aid of ultraviolet light, (pl. 5, fig. 1c) differs from that of any of the species figured in the present paper. It is more suggestive of the pattern sometimes noted on the above mentioned recent species.

C. drezi is named in honor of its collector, Paul Drez of Chapel Hill, North Carolina, who has a talent for locating unusual specimens.

 

 

 

Conus drezi

USNM 220123

mm. 30,0 x 16,3

 

 

 

 

 

 

 

 

Bibliografia Consultata

 

·         (1) - Hoerle, S. E., 1976. The Genus Conus (Mollusca: Gastropoda) from the Alum Bluff Group of Northwestern Florida. Tulane Studies in Geology and Paleontology, 12 (1 )