Some random members of family Orthalicidae

kw: natural history, natural science, museums, research, photographs

I have been in the midst of inventory of terrestrial snails of a large family that is popular with shell collectors, the Orthalicidae. The family is named for the genus Orthalicus, but the family contains numerous species in many genera. In recent years taxonomy professionals have split certain genera out into new families. But we tend to call all these species "Orthalicids". Today I just present a few that I ran across recently, showing some of the breadth of attractive shell forms in these families. Each image is followed by a caption.

These are two species in the genus Placostylus, P. scarabus (Albers, 1854) and P. seemani (Dohrn, 1861). They are found on the islands of the south Pacific: the former in New Caledonia and the latter in Fiji. These island nations are about 850 miles apart (~1,350 km), so there is little natural opportunity for these species to encounter one another. The Fijian shells are visibly narrower than the Caledonian.

These are two more species of Placostylus, P. strangei (Pfeiffer, 1858) and P. stutchburyi (Pfeiffer, 1860). Both are found on the Solomon Islands. The third row consists of five lots of shells that have been identified as Placostylus, but no species is yet assigned. I am particularly intrigued by the one shell with aperture showing, that is bright orange inside.

This closeup shows one lot of P. scarabus. I purposely turned one shell to show the aperture, which shows a pale orange inside, less prominent than the one in the former picture. This also shows the variety of coloration to be seen in a single species, from quite mottled and brownish to smoothly creamy.

I turned two of these shells, of the more distantly related species Auris melastoma (Swainson, 1820), to show the nearly black interior. "Melastoma" means "black mouth". These inhabit Brazil.

Finally, this is a closeup into the plastic box containing one lot of Berendtia taylori (Pfeiffer, 1861). These are from a little closer to home, for us Americans at least: on the Baja peninsula of Mexico. I wanted a closeup of these, to show the fine ridges that cover the shells. You can also see a relic of museum practice in three of the shells: Munroe Walton had written his own number inside the apertures, and these have been crossed out and the DMNH catalog number written there.