Strophia ianthina Maynard, 1889

Original Description

"STROPHIA IANTHINA Novo.

Violaceous Strophia.

Plate II, 13 & 13A, shell.

DESCRIPTION.

            SP. CH. Size, medium. Shell, rather heavy and elongated, the width being about one third the length. Striations, present. Teeth, two, both short and not prominent. Whirls, 11. Examined 300 specimens.

            Form of shell, cylindrical, the first three whirls being nearly equal in diameter and occupy more than two thirds of the length of the shell. The fourth whirl is but slightly smaller and from this, the shell tapers to a blunt point, forming an angle of 65 degrees. The striations are numerous, 24 on the upper whirl; they are prominent, very regular, and arranged in lines which are quite straight, being very little inclined from right to left; and the interspaces are little wider than the prominences. The striations are not furrowed and the edges are smooth and

rounded.

            Aperture, very large and open, measuring considerably more just within than at the entrance. Lower tooth very small, .02 high and .08 long, placed about in the centre, and the upper tooth is but a mere rudiment.

            Margin, not produced forward beyond the diameter of the shell, slightly inclined to the right, is thin, with the edge rolled well back, about once the thickness of the margin. The frontal bar is well developed and the striations appear within elevated.

            Color of shell externally, deep violaceous purple, gradually becom­ing reddish orange toward the apex which is nearly white. The margin, frontal bar and striations are white, the latter somewhat encroached up on, especially above, by violaceous. Internally, very deep, rich purplish brown.

DIMENSIONS.

            Size of types; 1.15 by .37 and 1.00 by .36. Largest specimen, 1.15 by .42; smallest, .85 by .30. Greatest diameter, .42, smallest, .30. Longest specimen, 1.15; shortest, .85.

OBSERVATIONS.

            The type form prevails but there is a tendency toward a smaller form with finer striations, but these specimens are possibly only reversions toward some of the several finely striated species that occur on Inagua. Distinguished at once from all others, by the deep purplish color of the aperture, the violaceous externally, and the rather widely separated, prominent, white striations.

DISTRIBUTION AND HABITS.

            I found this very handsome Strophia on the scattering shrubbery

that grows on the rocky plains between the elevations that skirt the

southern shore of Inagua, and the extensive salt lake of the interior,

about twenty-five miles from Mathewstown.

            This was during the very dry month of February, and they were fastened to the stems of trees and bushes. I think their range is some­ what further extended on this shore, but how far I cannot, at present, state."

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