Strophia agava Maynard, 1894

Original Description

"43 STROPHIA NEGLECTA AGAVA Novo.

Agava Strophia.

Fig. 48, A, front, B, side view, of type.

DESCRIPTION.

SP. CR. Size, rather above medium. Shell, thick and heavy. Whirls, ten. Striations, present. Examined 500 specimens.

     Form of shell, a pointed cylinder, with the first two whirls about equal in diameter, then the shell slopes gradually to a rather acute point, forming an angle of sixty-three degrees. Striations, rather numerous, twenty-four to the first whirl, they are rather narrow, not as wide as the interspaces, quite irregular, smoothly rounded, and inclined to be polished. They are slightly inclined from right to left, and well arranged in lines.

            Aperture, rather large, quite open, and not contracted at the the entrance. Lower tooth, quite prominent, about .05 high, and not quite twice as long as high, slightly elevated, and set back about once its length from the frontal bar. Upper tooth well developed, about half as large as the lower and is placed a little above the top of the lower.  

            Margin, produced forward about as far as the diameter of the shell, is placed quite nearly in the middle of the shell, and is only slightly inclined to the right. It is about twice as thick as the shell, is beautifully beveled, and projected backward into a blunt edge. The frontal bar is slightly developed, and the striations are indicated within it.

            Color of shell, externally, yellowish ash, striations and all; inter­nally, brownish, becoming paler on the teeth and margin.

DIMENSIONS

            Size of type, 1.21 by .47. Largest specimen, 1.35 by .50; smallest, .93 by .42. Greatest diameter, .50; smallest, .42. Longest specimen, 1.35; shortest, .93.

OBSERVATIONS.

Individual variation in this sub-species is toward a smaller form, with coarser, more widely-apart striations, thus passing through a small percentage of specimens into typical S. neglecta, and on the other hand, into a larger, heavier form, with striations about as in the type.

This well-marked sub-species differs from typical neglecta in the larger size, thicker margin, and more numerous striations. From all other Strophias it may be known by the acute apex and singular color.

HABITS AND DISTRIBUTION.

In March, 1893, I found the Agava Strophia common throughout the sisal fields to the westward of Nassau as far as the fields extend, and I traced it for about eight miles westward and about a mile back from the coast. The form becomes more typical as it recedes from the type location of S. neglecta, and we found some very fine, large specimens about a mile south of this point.

This shell, which has beyond all doubt, been developed into what is nearly a well-established species through the clearing of the fields, is frequently found clinging to the huge leaves of the sisal plants, but it is also found on herbage and shrubbery which grows in the fields." (Maynard, 1894:152-154).

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