Reverse Coiled Gastropods

Reverse Coiled Gastropods ~ H. G. Lee Collection ~

     A vast majority of the tens of thousands of marine and non-marine gastropod species are normally dextral (right handed - i. e., the shell opening is to the right when held spire upwards) while only a limited number of taxa such as Busycon perversum, the few species of the fasciolariid subgenus Sinistralia, and most of the speciose families Triphoridae and Clausiliidae, are normally sinistral (left handed - the shell opening visible on the left when held spire upwards). However, accidents of nature do happen, and occasionally a sinistral specimen of a normally dextral species or a dextral specimen of a normally sinistral species will be found - albeit rarely to uniquely. It is likely that most such reversals are caused by a single gene mutation.

     In some 48 years of specializing in "reverse coiled" or "abnormally sinistral or dextral" gastropods, Jacksonville amateur malacologist Harry G. Lee has assembled a collection of 175 individual species, eleven collected by himself, which had coiled in a direction contrary to the norm. This collection includes 106 Recent, four fossil marine and 65 non-marine species. A listing of the species is presented below by family in phylogenetic order; genus and species are thereinunder alphabetical. Shell measurement is presented in cm. followed by collection location and the year collected. A year listed in parentheses is the year a specimen was acquired when the actual year of collection was not known. A "+" following the listed entry indicates that more than one specimen is present in the collection.

Marine Gastropods

The thirty-year peregrination of the exquisite sinistral Ancillista velesiana Iredale, 1936: a chronology

Faux Sinistral Cymatium pileare (Linnaeus, 1758) From The Philippines

Faux Sinistral Conus From The Philippines

Faux Sinistral Cymatium pyrum (Linnaeus, 1758)

Which Way Does A Sundial turn?

Some of the specimens listed above on display at the Jacksonville Shell Club Show in June, 2007

Some of the specimens listed above on display at the Jacksonville Shell Club Show (June, 2007)


Page Two