Phylogenetic analysis of the Bunocotylinae dollfus, 1950 (Digenea: Hemiuridae).

The phylogenetic analysis of the 16 recognized genera in the Bunocotylinae, based upon 30 morphological transformation series, produced 2 most parsimonious trees, each with a consistency index of 0.62. The monophyly of the group is supported by 6 synapomorphies. Ahemiurus, Aphanuroides, Aphanurus, Myosaccium, and Indoderogenes separate independently in the basal part of the tree. Saturnius and Bunocotyle separate next, forming a clade. Machidatrema, Duosphincter, Theletrum, and Monolecithotrema separate independently; and in the most derived part of the tree Opisthadena + Neopisthadena + Mitrostoma, Genolinea, and Neotheletrum grouped together form a clade. Optimization of hosts and geographic distribution onto the 2 most parsimonious trees suggests that the bunocotylines originated from an ancestor that was host specific to fishes of the Clupeidae and was distributed in the Tethys Sea.