Strophia eurystoma Maynard, 1896

Original Description


            Wide-mouthed Strophia,

            Plate II fig. 3, front, fig. 4, side view of type.


            SP. CH. Size rather large, shell quite thick and heavy.    Striations, present. Whirls, 11. Examined 21 specimens. Form of shell pointed cylinder, with the first and second whirls the largest, then the third whirl is a little smaller, and from this, the shell slopes grad­ually to a point, forming an angle of fifty-five degrees. There are sixteen striations to the first whirl; they are not prominent, are rather irregular, not arranged in lines, nor furrowed, but rounded and polished, are narrow, the interspaces being twice as wide as they, and slightly inclined from left to right.

            Aperture large and open, about as wide as high, not at all con­tracted at the entrance. The lower tooth is small, about .07 long, and about half as high as long; it is set well back about twice its length from the frontal bar; it is about central in position. The upper tooth is about the same height but extends backward around the column.

            Margin not produced forward beyond the diameter of the shell, but is somewhat inclined to the right beyond the side of shell. It is thin, (about .03) considerably flanging, projecting outward about .10, and somewhat rolled over, but the edge is smooth. The frontal bar is not well developed and the striations appear quite prominently within it, ex­tending backward into the shell.


            Size of typical specimen, 1.35 by .40. Largest specimen, 1.36 by .47; smallest, 1.27 by .35. Greatest diameter, .48; smallest, 35. . Longest specimen, 1.38 ; shortest, 1.25.


            There is some individual variation in the inclination of the mar­gin; some specimens having this about straight. There is one de­veloped form.

            Form No. 1. More slender in form, and rather more acutely pointed, and while the striations are more numerous above, twenty-five to the first whirl, they are nearly or quite absent on the lower whirls. I found two of this form in the museum collection, but I find that out of seven shells received from another source, also labeled Havanna, that all, with a single exception, are of this form. Thus it may be possible that this will prove to be a sub-species, inhabiting a locality apart from the typical form.

            This species may be distinguished from all of the other flanging­mouthed Cuban shells, yet mentioned, by the open mouth, large size, and white, unflecked color. For comparison with S. infanda of Shuttleworth, see that species.

I found these shells bearing the label" Pupa mumia, Havanna Cuba."

            The color of the shell of S. eurystoma is yellowish white, externally, with the apex flesh color. Internally, pale brownish or flesh, fading into yellowish white on the teeth and margin. It is worthy of note that shells of the typical form, show stainings ofared ochraceous earth, while those which I have mentioned as form No.1, are either stained with a brown earth or are without staining, hence it is reasonable to suppose the forms do not occur together. Should this prove true, form No.1 must take subspecific rank, in which case it may be called Strophia eurystoma ignota."

Close Window