Strophia picta Maynard, 1889

Original Description

"6. STROPHIA PICTA Novo.

Painted Strophia.

Plate II, 6 & 6B, shell.

DESCRIPTION.

            SP. CH. Size, small. Striations, absent. Whirls, 10. Teeth, two, and quite long. Examined 75 specimens. Tentacles, short.

            Form of shell, a pointed oval, with the second whirl the largest; the first and third are about the same size and from the third, the shell tapers to quite a blunt point, forming an angle of about 60 degrees. The lines of growth are very faintly defined, and become prominent only on the top of the first whirl. These prominences begin on a line with the frontal bar, and end at a point about half way up the margin, on the right, thus occupying the top of the whirl, ending abruptly on the line drawn, the shell below this being smooth. Sutures, not deep.

            Aperture, rather small, but open, and the diameter of the cavity just within is a trifle more than at the entrance. Lower tooth, about central in position, and is .18 long by.05 high; the upper is situated just above it, is only .03 high, but makes a complete turn around the column.

            The margin is not produced forward beyond the diameter of the shell, it is not very thick, measuring only .08, and is provided on the outer posterior portion with a rather blunt edge which unlike the ma­jority of species, is not rolled backward. The frontal bar is not very well developed, and the lines of growth appear within it.

            Color of shell externally, bluish white, marked with rather zig zag longitudinal spottings of purplish brown, that are more numerous on the lower whirls. The margin, externally and internally, and the teeth are yellowish, but this color gradually deepens within to a purplish brown, which color pervades the lower wall and whole interior.

DIMENSIONS.

            Sizes of types, .96 by .40 and .86 by .39. Largest specimen, 1.04 by .41. smallest, .83 by .36. Greatest diameter, .46; smallest, .36. Longest specimen, 1.04; shortest, .83.

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, but scarcely constitute even a group. In color the inclination is to be redder in markings, than the types, and although a few show broader stripes, the tendency is to exhibit norrower [sic] ones, with broader areas of white. The margin is never very heavy, .10 being the extreme measurement, and the fact that the outer posterior portion is not rolled backward, is a marked feature and quite constant. The restriction of the prominent lines of growth, to the top of the first whirl is a usual, though not absolutely, constant character, it being ex­tended in some specimens, to the lower part of the whirl, but does not, extend very far back.

            Known from S. festiva, its nearest ally, by the small size, more regular markings, and thinner margin, and from all others, by the absence of striations, long teeth, and purplish markings.

DISTRIBUTIONS AND HABITS.

            This species occurs in a very limited area, on the west end of Little Cayman. Near the southern termination of the western path that ex­tended across the key, or rather near its junction with the main path, was a patch of guinea-grass; in this, were numerous open spots, and in them, or on their borders, these Strophias lived, occupying in all about a half acre.

            The habits of the Painted Strophias are rather more social than those of the Pictured, as they occur in small groups of a half dozen or more, but are nowhere common." (Maynard, 1889:18-20)

Close Window