Morphometric evaluation of 20 Heterorhabditis isolates from Puerto Rico

Abstract

From November 1992 through January 1993 soil samples were collected from different localities of Puerto Rico to isolate entomopathogenic nematodes. Samples were baited with the greater wax moth, Galleria mellonella, under laboratory conditions. Nematodes belonging to the genus Heterorhabditis were isolated from 20 of the baited samples. The nematodes could not be properly identified to species but were found closely related to H. bacteriophora and H. indicus. Thirteen morphometric characters of the infective third-stage juvenile were measured for each isolate and subjected to evaluation by Standard Descriptive Statistics, Stepwise Discriminant Analysis, Canonical Discriminant Analysis and Hierarchical Cluster Analysis. Results suggested the presence of a new species of Heterorhabditis with sufficient variation among the isolates to separate three different subgroups.