Redescription of Cardimyxobolus donkoi n. comb., with Synonymization of Cardimyxobolus japonensis (Cnidaria: Myxosporea: Myxobolidae) and Remarks on the Authorship of Ortholinea

Abstract

Myxobolus donkoi Ishizaki, 1955 (Cnidaria: Myxosporea), originally described in Fukuoka Prefecture, Kyushu, Japan, was redescribed based on newly collected specimens from the intestinal wall of its type host, Odontobutis obscurus (Temminck and Schlegel, 1845) (Gobiiformes: Odontobutidae), and newly classified in the genus Cardimyxobolus Ma, Dong, and Wang, 1982 as C. donkoi n. comb. These specimens were obtained from Kumamoto Prefecture (Kyushu) and Yamaguchi Prefecture (Honshu). Cardimyxobolus japonensis Li and Sato, 2014 (Myxosporea), also described from the intestinal wall of Od. obscurus in Yamaguchi Prefecture, is regarded as a junior synonym of C. donkoi n. comb. based on identical morphological features and molecular analyses of 18S and 28S rDNA sequences. The authorship of Ortholinea, type genus of Ortholineidae, has traditionally been attributed to Shulman (1962). However, because Shulman (1962) did not meet the requirements of Article 13.3 of the International Code of Zoological Nomenclature, the authorship of the genus is attributed to Lom and Noble (1984), who first designated its type species. Because recent phylogenetic studies have clearly demonstrated that Ortholineidae is polyphyletic, this study follows previous proposals assigning Ortholinea to Myxobilatidae. Among the genera previously included in Ortholineidae, I propose transferring Cardimyxobolus and Triangula Chen and Hsieh, 1984 to Myxobolidae based on the morphology of their plasmodia and phylogenetic relationships. In addition, Neomyxobolus Chen and Hsieh, 1960, for which molecular data are currently unavailable, is tentatively assigned to Myxobilatidae.