Submitted to: Systematic Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 14, 1998
Publication Date: N/A
Interpretive Summary: Cyclophyllidean tapeworms are among the most diverse parasites in mammalian and avian hosts, are significant pathogens in domestic animals, and are primary and zoonotic parasites in humans; they are the most economically and medically important group of tapeworms. Although the focus for study over the past century, there has been limited consensus about evolution, and host- parasite relationships. This has hindered unambiguous diagnostics and has an impact on the development of control programs. The first phylogenetic study among the families of cyclophyllideans supported monophyly for the order. The hierarchical relationships postulated for the families now makes it possible to conduct detailed evaluations of the Taeniidae, including Taenia and Echinococcus, medically and agriculturally the most significant tapeworms. Studies of cyclophyllidean families are the initial step in a program to complete phylogenies within the taeniids.
Phylogenetic analysis of the families of the Cyclophyllidea based on comparative morphology revealed support for monophyly of the order. Four equal length trees (Cl=0.705) resulted from analysis of 42 binary and multistate characters. Major conclusions are the following: (1) a basal position for the arostellate groups, with Mesocestoididae + Nematotaeniidae representing the basal subclade; (2) polyphyly for Anoplocephalidae with sister-group associations postulated respectively for Anoplocephalinae + Thysanosomatinae and Linstowiinae + Inermicapsiferinae; (3) recognition within the rostellate cyclophyllideans of taeniids, dilepidid and davaineid subclades and Dipylidiidae; (4) designation of Metadilepididae + Paruterinidae as sister taxa; (5) monophyly for Davaineidae with all inclusive subfamilies; and (6) a close relationship for the Hymenolepididae and aculeate cyclo0hyllideans. Monophyly for such classically defined groups as the Mesocestoididae, Taeniidae, and Davaineidae is corroborated. Polyphyly of the Dilepididae sensu lato, with independence of the Dipylidiidae, Dilepididae sensu Bona, 1994, the Metadilepididae + Paruterinidae, and Gryporhynchidae is confirmed. As presented these constitute testable hypotheses for monophyly and relationships among the families of the Cyclophyllidea.