Original Combination:

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Original Description:

The shell is narrowly perforate, with a rather long rimation, discoidal, the spire very slightly convex; whitish corneous (probably partially bleached), glossy, with faint sculpture of weak growth lines only. The whorls increase slowly ; the last one is rounded at the periphery and descends abruptly at the aperture ; it is constricted and opaque white behind the lip, and there is a short oblique groove within the umbilicus. Aperture very oblique. The peristome is thick, expanded outwardly, reflexed below, the ends connected by a rather thick callus, which bears a rather long, obliquely V-shaped tooth, the upper branch of which, though not so high as the lower, is well developed and connects with the peristome. There are two strong lip teeth, the upper one peripheral in position, tubercular, the lower one basal, compressed, entering across the lip-callus; a low, rather sharp lip-callus, more immersed at its lower end, is above the upper tooth. Alt. 4, diam. 9.6 mm.; width of umbilicus 2.6 mm.; whorls 5. Tampico, in river debris, coll. by A. A. Hinkley. This species closely resembles P. texasiana hyperolia Pils. and Ferr., but it differs by the wider constriction or furrow behind the peristome, and the decidedly more deeply immersed upper lip tooth. The umbilical rimation is also longer than usual in that form.