Megalobatrachonema (Chabaudgolvania) waldeni n.sp. (Nematoda: Kathlaniidae) from the intestine of the northwestern salamander, Ambystoma gracile (Baird)

Abstract

A new species of kathlaniid nematode, Megalobatrachonema waldeni, from the intestine of the northwestern salamander, Ambystoma gracile, in British Columbia is described. The new species is placed in the subgenus Megalobatrachonema (Chabaudgolvania) as it lacks valves in the oesophageal bulb. Megalobatrachonema waldeni differs from the two other members of this subgenus, M. elongatum (Baird, 1958) and M. terdentatum (Linstow, 1890), in having large cervical alae and distinctly separate lips, and in lacking hypodermal lip peduncles and a pseudosucker. Megalobatrachonema waldeni has simpler onchia, smaller spicules, and a more prominent swelling at the base of the oesophageal corpus than M. elongatum, and differs from M. terdentatum by its distinct corpus swelling, more anterior excretory pore, fewer caudal papillae, and longer tail.