Strophia parva Maynard, 1889

Original Description

"9. STROPHIA PARVA Novo.

Little Strophia.

Plate II, 9 & 9B, shell.

DESCRIPTION.

            SP. CH. Size, very small. Striations, present. Teeth, two, and rather long. Whirls, 9. Tentacles, quite short. Examined about 1,000 specimens.

            Form of shell, nearly oval, with the second whirl the largest; the first and third are a trifle smaller and about the same size, from the third the shell tapers to quite a blunt point, forming an angle of about 60 degrees. The striations are 18 on the first whirl, are quite promi­nent, slightly furrowed, but with the edges rounded; the interspaces are narrower than the prominences. Sutures, rather deep.

            Aperture, not very small, but open, and the diameter of the cavity just within is a trifle more than at the entrance.  Lower tooth, placed a little to the right of the center, and is .16 long by .05 high; the upper is situated just above it, is only.02 high, but makes a complete turn around the column.

            The margin is not produced forward quite as far as the diameter of the shell, it is not thick, measuring only .06, and is provided on the outer posterior portion with a rather blunt edge which is slightly rolled back­ward. The frontal bar is quite well developed, and the striations do not appear within it.

            Color of shell externally, dull white, with an occasional patch of pur­plish yellow which is due to a wearing away of the outer surface through abrasion. The margin, externally and internally, and the teeth are yellowish, but this color gradually deepens within to a purplish yellow which color pervades the whole interior.

DIMENSIONS.

            Sizes of types, .60 by .30 and .63 by .32. Largest specimen, .72 by .32; smallest, .60 by .30. Greatest diameter, .37; smallest, .27. Longest specimen, .72; shortest, .68.

OBSERVATIONS.

            The type is very constant and the principal departure from it, is a form that is proportionately longer and more cylindrical, but tapering from the second whirl to the apex. Individuals are shorter and with a larger diameter than the types, with from 20 to 24 whirls and may con­stitute a group. In color there is an inclination to show fleckings and to increase the worn patches. The margin, as a rule, is not heavy, but now and then this is thickened, .10 being the extreme.

            Known from all other species, by the presence of striations, small size, less than .73 long, and long teeth.

DISTRIBUTION AND HABITS.

            This species occurs in a very limited area, on the west end of Cay­man Brac. Near the northern termination of a path that crosses the key near the western end, is a strip of quite high shrubbery, and in this these Strophias lived. From this point, they were scattered at inter­vals, quite into the large colony of Common Strophias, in the cocoa-nut grove on the south side, having evidently been inadvertently transported by the inhabitants.

            In habit these Strophias are decidedly social occurring in groups of a dozen or more, clinging to the branches of the shrubbery, often at a considerable distance from the ground, sometimes five or six feet, dif­fering in this respect, from any other species that I have seen living, it not being usual for them to ascend more than one half of this distance." (Maynard, 1889:24-25)

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