THE OVARY AND ANAL PROCESSES OF "CHARACODON" EISENI, A VIVIPAROUS CYPRINODONT TELEOST FROM MEXICO

¹ Biology Department, Grinnell College, Grinnell, Iowa

The ovary and trophotaeniae of "Characodon" eiseni Rutter are described. The median septum of the ovary is variable in structure; the septum may be a single, continuous sheet or it may be divided into dorsal and ventral halves. Ovigerous tissue is confined primarily to the anterior region of the ovary but mostly to the ovarian wall. There are four trophotaeniae (processes), two lateral and two median, one anterior and one posterior to the anus. The processes are further described as sheathed. The above facts are not in agreement with previously published descriptions of Xenotoca variata with which this species has been synonymized. The above facts are further contradictory with each other in assigning "Characodon" eiseni to a particular evolutionary line within the family Goodeidae. The paper shows that the goodeid taxonomic criteria based on ovarian and trophotaenial structure are not discriminatory when applied to "Characodon" eiseni.