Conus tapetus (Hoerle, 1976)

Diagnosis ⁽¹⁾:

Shell nearly straight-sided, low spired, early whorls elevated. Adult specimens with nine teleoconch whorls plus one and three-quarters smooth, broadly rounded nuclear whorls. First three or four post-protoconch whorls with beaded shoulders, remainder smooth. Sutures lightly adpressed, bounded in front by a cord. Summits of spire whorls flat, ornamented with spiral threads; growth lines faint, close-set, arcuate. Anal fasciole flat; shoulder subacute; outer lip nearly straight in front of deep anal notch. Columella straight with a slight thickening at base; scarcely discernible siphonal fasciole. Spiral sculpture on last whorl confined to anterior third of the shell, consisting of eight to twelve unequal and inequispaced flattened cords, heavier on their adapical edge.

Dimensions of holotype: height 31.6 mm, diameter 17.4 mm.

Holotype: USNM 220112.

Type locality: TU 547, west bank of Chipola River, about 2000 feet above Four Mile Creek (SW ¼ Sec. 29, T1N, R9W), Calhoun County, Florida.

Occurrence: Chipola Formation, Florida; late lower Miocene.

Figured specimens: Fig. 4, USNM 220112 (holotype). Fig. 5, USNM 220113; height 8.6 mm, diameter 4.6 mm; locality TU 825.

Other occurrences: TU locality nos. 457, 458, 459, 548, 554, 555, 818, 819, 820b, 821, 822, 823, 824, 826, 827, 828, 999, 1020, 1048, 1050.

Discussion: After C. isomitratus this new species is the most common of the cones collected by the writer along the Chipola River. The greatest numbers were taken from two coral reef localities, TU 547 ( 190 specimens) and TU 555 (62 specimens). C. tapetus is extremely rare at "one mile below Bailey's Ferry" (TU 457) and does not occur at "one mile west of Bailey's Ferry" (TU 546 ). As these were the only two localities available to early workers, it is understandable why this distinctive species is totally absent from the older collections.

C. tapetus bears a greater similarity to C. erugatus n. sp. than to any other species from the Chipola Formation. Both have beaded early whorls and a nearly straightsided outline of the final volution. C. tapetus can easily be separated from its congener by the adpressed suture, spiral lineation, and larger size. Adults of C. tapetus average 30 to 35 mm whereas those of C. erugatus seldom reach 25 mm. This species demonstrates the unreliability of employing basal ornamentation as a diagnostic feature for means of identification. The cords, confined to the anterior third (sometimes to the anterior fifth only) of the shell, may be flattened, rounded, coarse or fine, all within the species. Those specimens from the river localities TU 547 (type locality) and TU 555 fluoresce exceedingly well (pl. 3, fig. 4b ), showing a pattern remarkably like a piece of finely woven tapestry. The Latin word tapetus, meanmg "tapestry" is descriptive of the species.