Fatty acid distribution in salamanders of the family Plethodontidae

Fatty acid distributions in tissues from salamanders of the family Plethodontidae were compared to determine the feasibility of using such differences as a taxonomic tool. Intraspecific, generic, and interspecific variations in the fatty acid composition of one species of genus Desmognathus, two species of genus Eurycea, four species of genus Plethodon, and one species each of genus Gyrinophilus and genus Pseudotriton were compared.Intraspecific variation in fatty acid percentages were found when sex, size, season of collection, geographic locality, and altitude were compared on a variety of tissue extracts. Sex and geographic differences seemed to be of the least importance, while differences in the other three comparisons were distinct. Fatty acid compositions of salamanders of various sizes were compared and it was found that tissues of larger salamanders had smaller percentages of short chain fatty acids.Seasonal variation was apparent in that there was an increase in short chain fatty acid percentages of tissues of salamanders collected toward the fall, compared to those collected in the spring. Tissues of specimens from higher elevations were found to have more short chain fatty acids than those from lower elevations.A trend toward larger proportions of short chain fatty acids was found among salamanders of genus Eurycea, which has the greatest diversity in habitat. This trend graded toward lower percentages as the genera became more aquatic, as in genus Gyrinophilus and genus Pseudotriton, or more terrestrial, as in genus Desmognathus and genus Plethodon.Few interspecific variations were found which would allow consistent differentiation between species. One notable exception was the presence of fatty acid 17:2 in Eurycea multiplicata multiplicata, and not in the other species of Eurycea.This study suggests that the biochemical taxonomic differentiation of salamanders of family Plethodontidae using fatty acid distribution, may be possible in a more comprehensive investigation using larger sample sizes.Ball State UniversityMuncie, IN 47306Thesis (M.S.)--Ball State University, 1975