STEINERNEMA CUBANA SP-N (NEMATODA, RHABDITIDA, STEINERNEMATIDAE) AND THE PRELIMINARY CHARACTERIZATION OF ITS ASSOCIATED BACTERIUM

Steinernema cubana sp.n. from Cuba is described. The nematode was isol ated from soil samples in citrus plantations. This nematode and Steine rnema glaseri and Steinernema anomali constitute a morphological group of closely related species; however, no fertile crosses were observed among these three species. Infective juveniles of S. cubana are very long, averaging 1283 mu m and ratios D = 0.7 and E = 1.6, higher than those in S. glaseri and S. anomali. The excretory pore of adults is lo cated close to the nerve ring or more posterior to the mid part of the basal bulb of the esophagus. The mucron is absent on the male tail. T he spicule tip is blunt, without a hook-like structure. The manubrium varies in its shape; its length to width ratio is 1.5 to 1. S. cubana can be cultured on Galleria mellonella larvae. The bacterial symbiont belonging to the genus Xenorhabdus is a gram-negative rod-shaped bacte rium. The cell size ranges from 0.4 x 2.0 to 2.0 x 5.0 mu m. (C) 1994 Academic Press, Inc.