Pharyngodon armatus Walton, 1933 (Nematoda: Oxyuridae); Description of the Male and Redescription of the Female

Abstract

Pharyngodon armatus was originally described from female specimens only. Male and female specimens have been recovered from the intestine of green frog tadpoles (Rana clamitans melanota). The male of the species is described for the first time and the female is redescribed. Male and female specimens of the genus Pharyngodon were recovered from the intestine of green frog tadpoles (Rana clamitans melanota) collected from Pond 26, Delaware Game Preserve, Delaware County, Ohio. Seven species of Pharyngodon have been reported from amphibians by Walton (1929, 1933, 1940), Baylis (1930), Yamaguti (1941), Johnston and Mawson (1942), and Ubelaker (1965). Only three of the seven species have been described on the basis of male and female specimens. Pharyngodon spinicauda, the type species, was originally described from the reptile, Lacerta muralis. It has since been recovered from Triturus vulgaris. Pharyngodon armatus was described from female specimens only by Walton (1933). While reviewing a type specimen of P. armatus obtained from the USNM Helm. Coll. No. 27061, I noted discrepancies in the original description of the females. Inconsistencies included the position of the excretory pore, operculum on the eggs, the prominence of the lips, and the beginning of cuticular striations. The newly recovered females were conspecific with the type specimen. Since the original description was incomplete and since male specimens were recovered, I have deposited the Ohio specimens and the following description of the male and redescription of the female are given. MATERIALS AND METHODS The nematodes were fixed in steaming 70% alcohol and cleared in alcohol-glycerine. Living and fixed specimens were examined with light and phase contrast microscopes. The 25 male and 25 female specimens used in this study were temporarily mounted under supported cover slips. All measurements are in microns, unless otherwise Received for publication 6 August 1968. indicated. The range is followed by the average in parentheses. Drawings were made with the aid of the camera lucida. Pharyngodon armatus Walton, 1933 (Figs. 1-8)