Conus
trinitatensis (Mansfield, 1925)
Description:
Shell small,
moderately stout, diameter about one-half length of shell, eight and one-half whorled-
Last two whorls of spire nearly flat, the rest rising rather steeply to an
altitude 4 mm. above the plane of the spire. Nucleus small, smooth, with one
and one-half whorls. First two postnuclear whorls carinated and turrited.
Suture of the earlier whorls shallowly channeled and somewhat appressed, on
later whorls less appressed and deeper channeled. Last three whorls moderately
medially concave. Sculpture of spire consists of a strong, flat, raised spiral
band in front of the suture closely followed by three small, rounded, equally
spaced spiral threads occupying two-thirds of the remaining space. Concave
arcuate growth lines overrun spirals and extend from suture to suture. Last
whorl with low carina at the shoulder and sculptured mainly on the lower
two-thirds with narrow bands with wider interspaces occasionally carrying an
intermediate thread. Outer lip broken away. Aperture moderately narrow.
Columella nearly straight, slightly incurved and dorsally reflected.
Dimensions: Type (XL S. Nat. Mils. Cat, No.
352645) measures: Altitude 20 mm. ; maximum diameter 10 mm, ; altitude of
spire, 4 mm.
The most
prominent character of the new species is the strong spiral band in front of
the suture of the spire. It is somewhat similar to C.
submoniliferus Gardner (Ms.), a species occurring in the Shoal River
marl member of the Alum Bluff formation of Florida, but possesses a
proportionally lower spire and different arrangement of spirals.
Occurrence. —
Middle or lower Miocene: Guaico-Tamana Road, 2 chains east of mile 13 from
junction with Eastern Main Road, Trinidad, British West Indies.
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Conus trinitatensis (1) Plate 1, figg. 1, 4 Miocene mm. 20 x 10 Trinidad |
Bibliografia Consultata
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(1) - Mansfield, W. C., 1925. Miocene
Gastropods and Scaphopods from Trinidad, British West Indies. Proceedings
of the United States National Museum, 66 (2259 ): 1 -65
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