The Distribution of Plethodon glutinosus (Green) in Central Louisiana with a Taxonomic Comparison to Neighboring Populations

Abstract

During the past decade, collections from central and north central Louisiana have produced numerous specimens of Plethodon glutinosus from 7 parishes. This population was compared to populations from southwestern Arkansas and from Louisiana east of the Mississippi River. Specimens from central Louisiana and southwestern Arkansas possessed a pattern of larger and more numerous iridophore spots which tend to coalesce and form lateral blotches, whereas specimens from Louisiana east of the Mississippi River possess few lateral spots. Based on the size and number of iridophore spots, the central Louisiana population seems to be distinct from the other two samples. Animals in both Louisiana populations reach a smaller size than those in the Arkansas population further north. The range of the slimy salamander, Plethodon glutinosus (Green), includes an extensive part of the eastern United States and extends west of the ateMississippi River from southern Missouri, eastern Oklahoma, mountainous regios of Arkansas, and eastern and central Texas. P. glutinosus was first reported from northwestern Louisiana by Beyer in 1900. Bishop (1943) and Cagle (1952) describe it as ranging statewide in Louisiana, while Dunn (1926), Grobman (1944), Conant (1958), and Highton (1962) give no indication of it ranging in Louisiana west of the Mississippi River. Wilson (1966) collected an adult P. glutinosus from LaSalle Parish, Louisiana. This appears to be the first documented record from central Louisiana. This study was initiated during the summer of 1968 to determine the distribution and taxonomic status of P. glutinosus in Louisiana west of the Mississippi River. The three populations examined will be referred to as the central Louisiana population, the Arkansas population, and the east Louisiana population.