Spinitectus mariaisabelae n. sp. (Nematoda: Cystidicolidae) from the intestine of the freshwater fish Profundulus punctatus (Cyprinodontiformes) in Mexico

Spinitectus mariaisabelae n. sp. is described from the intestine of Profundulus punctatus (Günther) (Pisces, Cyprinodontiformes) from the Suchiapa River, State of Chiapas, Mexico. It is characterized largely by the bifurcate distal tip of the larger (left) spicule, spination of the cuticle separated into 4 longitudinal sectors, more or less regularly spaced rings of spines, and by the position of the excretory pore just posterior to the 7th ring of visible spines. By having the rings of spines divided into 4 sectors, the new species resembles 8 of the 15 American species; however, they can be easily distinguished by the number of spines in the first ring. S. mariaisabelae differs from all its American congeners by possessing a bifurcate distal tip of the left spicule, a unique feature among Spinitectus spp.