Thursday, June 19, 2014

More information about Campanile snail

This is the second part of my post on Campanile, the genus that includes the largest snail of all time = C. giganteum.

This sketch shows the aperture of this species. The aperture is the  the shell's anterior end, where the gastropod would have been able to extend its body out into the surrounding environment. In the previous blog, the illustrated specimen of this species showed the dorsal side of the shell, and most of the aperture was missing.

Sketch of ventral side of Campanile giganteum with its aperture intact.

The specimen shown in following picture is only the upper part of a very well preserved specimen of Cgiganteum from middle Eocene deposits in the Paris Basin, France. Notice that the axis (columella) of the shell bears two revolving features called folds or plaits. This type of morphologic feature is very important in the classification of gastropods.
upper part of shell of Campanile giganteum
height 22.5 cm

Fossil Campanile species have been found in Paleocene and Eocene deposits of California. The following picture is of an incomplete specimen (tip is missing) of Campanile dilloni Hanna and Hertlein, 1949 from a deposit of late Paleocene age in southern California. This species was not as large as C. giganteum

Campanile dilloni
height 15.5 cm

Today, Campanile is represented today by a single (relict) species, Campanile symbolicum Ireland, 1917, shown in the following picture. This snail crawls around on the seafloor in warm-shallow waters in the Perth area of southwestern Australia. This species is also known by the popular name "Bell Clapper" shell because of its overall shape. Also notice that the end of the columella (see above) is twisted and also has a narrow but distinct "spout." These features are also important in classification.

F.Y.I. The name "Campanile" is Italian, meaning "bell tower." There is tall tower, called "Campanile" on the campus of University of California, Berkeley. 

Campanile symbolicum
height 15.5 cm

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