WALKER, J.M.*; HOPKINS, T.S.: Morphological Analysis of Melongena corona Gmelin, 1791 Populations from the Gulf of Mexico (Gastropoda, Melongenidae)

The current classification of Melongena corona in the Gulf of Mexico is based on morphological shell characteristics. Within the Gulf, this classification recognizes two species, Melongena corona which consists of three subspecies (Melongena corona corona, Melongena corona johnstonei, and Melongena corona altispira) and Melongena bicolor. Of the subspecies recognized for Melongena corona, M. corona corona and M. corona johnstonei occupy the largest geographical ranges along the Florida Gulf coast and share an area of subspecific overlap which is approximately 150 miles in length. For this analysis, 30 individuals from 14 populations along the Alabama and Florida Gulf coasts were measured as to shell height, shell width, spire height, spire width, aperture height, and aperture width. Using these measurements, populations were analyzed using a sheared principal components analysis (PCA) to factor out for individual size differences within population samples. Scatterplots generated as a result of this analysis demonstrate that populations from all three M. corona subspecific ranges overlap with minimal graphical separation. In conclusion, this study shows little support for the current M. corona subspecific classification based on the morphological characters utilized in this analysis.