Strophia copia Maynard, 1889

Original Description


Common Strophia.

Plate I, 1 & 3, jaw; 7, 8, 9, 10, 11, & 12, structure. Plate II, 8 & 8B, shell.


            SP. CH. Size, medium. Shell, rather heavy. Striations, pres;ent. Tentacles, about one third as long as eye peduncles. Teeth, two and quite long. Whirls, 10. Examined 10,000 specimens.

            Form of shell, cylindrical, with the first three whirls about equal in diameter. From the third whirl, the shell slopes rapidly to a point, making an angle of 65 degrees. The striations are rather numerous, 23 on the upper whirl, prominent, and regular, although not arranged in lines; they are slightly inclined from right to left, and the interspaces are about one third as wide as the prominences. The striations are very slightly furrowed on the top, and the edges are quite smooth and rounded.

            Aperture, large and open, measuring a trifle more just within than at the entrance. Lower tooth, not very prominent, .05 high by .20 long. and its position is a little more than its width to the right of the cen­ter; the upper is not as prominent, is placed considerably above it, .05, and measures .02, but makes a complete turn around the column.

            Margin, not produced forward beyond the diameter of the shell, but is inclined slightly to the right, beyond the side; it is not greatly thickened, measuring .06, but the outer posterior portion is produced backward into a thin, but not prominent, edge that is rolled slightly downward. The frontal bar is quite prominent and interrupts the stri­ations. Animal, not large; jaw, smooth.

            Color of shell, externally, white. The frontal bar, teeth, and mar­gin, externally and internally, are flesh color, but within the aperture this color gradually deepens into purplish brown, which pervades the whole interior. Color of animal, horn, with a shaped mark of brown on the back.


            Size of types, .90 by .40 and .95 by .40. Largest specimen, 1.07 by .45; smallest, .75 by.32. Greatest diameter, .45; smallest, .46 . Long­est specimen, 1.07; shortest, .75.


            Among the large amount of shells that have passed through my hands, the typical form prevails, but there are, at least, four distinct forms in which certain characters are quite constant, but there is by far too large a percentage of gradation between them and the types, to ad­mit giving them a name, excepting, perhaps in one instance. The first form that I shall mention, is of small size, the smallest dimensions given, but the proportions are the same, however, as the types; next comes one that is more cylindrical than the types, the third whirl being but little smaller than the those above it, and it is proportionately more slender; then we have a shorter and proportionately much thicker form in which the width is but a trifle less than one half the length; in these three forms, the whirls are 10. The fourth form is one that has occasioned me some perplexity; it is large, the largest size given, the shell is quite thick and heavy, the aperture is inclined somewhat to the right, and above all, the whirls are 11. Could I have been sure that this shell gathered in localities of its own, apart from others, I should consider that it pos­sessed important characters enough to entitle it to a name, but I cannot remember that I found it separate anywhere, nor did I make any notes on it. In color of S. copia, there is a slight inclination to a brownish flecking.

            Known from all others by the numerous striations, 22 or more, size, .75 or more long, 10 or 11 whirls, absence of any decided markings, and long teeth.


            The Common Strophia occurs on the west end of the island of Cay­man Brac, and at a fishing camp on the north side of Little Cayman, also scatteringly about the houses on the west end of this key, but was probably carried to the two latter named places, by the inhabitants, the animals crawling upon their boats, or lumber, etc., and were in this manner transported.

I do not remember ever having seen any species of Land Shell, more abundant [than] this species of Strophia. In the shrubbery that bordered the paths and roads about the west end of Cayman Brac, they were very common, clinging to the base of the bushes, in masses, but their stronghold was the cocoa-nut grove on the south shore of the key, just opposite the few houses at the west end; here they absolutely swarmed in certain spots. Not only was the low herbage covered with them, but they fairly whitened the bases of the stems of the cocoa-nut trees, and often accumulated in such numbers on the small stumps, that they clung one top of another, often three or four deep, and could be gathered by the double handfuls. As the weather was mostly dry, they did not move much, so I could not decide upon what plant they fed, but judging from their numbers, this food plant must have been abundant, and by cultivation of the soil, the Strophias were placed under favorable cir­cumstances for the increase of the species. Through the agency of man, three or four other species had been introduced into this large colony which occupied in all, about half a square mile of country." (Maynard, 1889:22-24)

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