|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||Age range and collections|
Gastropoda - Personidae
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|A. G. Beu 1988||Shell small (to 25 mm high in P. grasi ; not over 20 mm high in other species), with slightly irregular whorl coiling; sculpture of regularly cancellate spiral cords and axial costae, all relatively low and closely spaced, with several orders of closely spaced interstitial spiral threads ; terminal varix low and narrow but obvious, earlier varices low and indistinct, situated regularly at each 0.66 whorls ; last whorl tapering gradually to a moderately short, open anterior canal that curves gently to left and dorsally; inner lip spread widely (but much less so than in Distorsio) to form a thin, adherent shield over parietal area, over lower third to half of last whorl to left of aperture, and over columella, smooth except for one or two low parietal ridges, and four or five low transverse ridges (the uppermost the largest) on the basal columellar area and left edge of anterior canal ; interior of outer lip bearing a row of seven of eight short radial ridges, all low and narrow except for the third from top, which is elevated into a large,' rounded nodule.|