Strophia festiva Maynard, 1889

Original Description

"5. STROPHIA FESTIVA Novo.

Pictured Strophia.

Plate II, 5 & 5B, shell: 5c, young.

DESCRIPTION.

                SP. CH. Size, large. Shell, robust and heavy. Striations, absent.

                Tentacles, short, about one third as long as eye peduncles. Teeth, two, both very long. Whirls, 11. Examined 22 specimens.

                Form of shell, inclined to cylindrical, the first and second whirls being equal in diameter, and the third is but little smaller, and from this the shell tapers to quite an acute point, making an angle of .55 de­grees. There are only faintly defined lines of growth which, however, assume more prominence on the back of the upper whirl, but these prominences are widely separated and irregular. The sutures between the whirls are not deep.

                Aperture, rather small, but open, the diameter of the cavity slightly increasing just within the entrance; the teeth are prominent, the lower, which is placed midway between the two walls, is .25 long and about .05 high, and the upper which is situated just above it, measures only .03, but makes a complete turn around the column.

                The margin is not produced forward beyond the diameter of the shell, and is not greatly thickened, measuring .08, and the outer poste­rior portion is provided with a thin, quite prominent, edge. The frontal bar is not very prominent.

                Color of shell, externally, bluish white, marked with longitudinal spots of purplish brown, that from the third whirl downward exhibit a tendency to become fused together and form rings near the middle of the whirls. The spottings are somewhat interrupted, and are fewer on the upper, and more numerous on the lower whirls. The frontal bar, teeth, and margin, externally and internally, are flesh color of quite a dark shade, but within the aperture this color gradually deepens into purplish brown, which pervades the whole interior.

DIMENSIONS.

                Size of types, 1.20 by .50 and 1.18 by .4S. Largest specimen, 1.24, by .54; smallest, .95 by .46. Greatest diameter, .54; smallest, .46'. Longest specimen, 1.24; shortest, .56.

OBSERVATIONS.

                The typical form given prevails but there is a tendency to a more pointed apex, with the second whirl smaller than the first; this form is figured on Plate II, 5. The margin of some specimens is very much thickened, the extreme measuring .13. In color, there is some variation in markings; although in two instances the spottings are more restrict­ed than the type, in the majority of cases they are more extended, and in two shells the purplish brown predominates. The tendency to assume rings on the lower whirls is quite prominent, and is an unusual feature in Strophia.

                Known from all others by the large size, absence of striations, long teeth and purplish markings.

DISTRIBUTION AND HABITS.

                On the western path that crossed the island of Little Cayman, of which I have spoken in my account of the preceding species [S. intermedia], about midway between the two shores, or a little nearer the northern, being thus a short half mile from the sea, were two small fields, or cultivated patches of land, containing, perhaps, a quarter of an acre each. In these limited areas I found the few specimens of the Pictured Strophias that I was able to obtain.

                In habit these Strophias are one of the most solitary species that I have ever seen living, for they occur in very scattering groups on the low herbage that margins the fields; and thus limited, were not common."  (Maynard, 1889:17-18)

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