Taxonomic review of Skrjabinotaenia Akhumyan, Meggittina Lynsdale and Gerbillitaenia gen. nov. (Cestoda: Catenotaeniidae), parasites of rodents

The present study concerns the classification and morphologic features of species variously assigned to the genera Skrjabinotaenia Akhumyan, 1946 and Meggittina Lynsdale, 1953 (Cestoda: Cyclophyllidea: Catenotaeniidae), particularly those characterized by a widely divided testicular field. The latter feature together with the typical structure of the ovary and uterus give grounds for assigning Skrjabinotaenia oranensis (Joyeux & Foley, 1930), Meggittina baeri Lynsdale, 1953, M. cricetomydis (Hockley, 1961) and M. gerbilli (Wertheim, 1954) to the genus Skrjabinotaenia sensu stricto ("s. s."). Skrjabinotaenia s. s. is characterized by an ovary without anterior lobules and with a prominent unbranched "antero-poral lobe" as well as a uterus with a short anterior trunk and a few long primary branches. Skrjabinotaenia s. s. is divided here into two subgenera (Skrjabinotaenia and Meggittina) based on the size and shape of the strobila and characteristics of the uterus. The present study provides amended diagnoses for Skrjabinotaenia s. s., subgenus Meggittina and redescriptions of their type species. In addition, a new genus (Gerbillitaenia gen. nov.) is erected for G. psammomi (Mihkail & Fahmy, 1968) n. comb. The phylogenetic position of G. psammomi, a species with a widely-divided testicular field, is unknown but it lacks the distinguishing features of Skrjabinotaenia s. s. concerning the structure of the ovary and uterus. Based on phylogenetic and morphologic evidence, Skrjabinotaenia sensu lato includes at least three additional lineages, which should be further examined as putative new genera.