Preliminary phylogenetic analysis of subfamilies of the Proteocephalidea (Eucestoda)

Abstract

Cladistic analysis based on comparative morphology was used to examine the subfamily-level relationships within the cestode order Proteocephalidea. A single most parsimonious tree (70 steps, CI = 0.571; RC = 0.295; HI = 0.471) is consistent with monophyly for the Proteocephalidea and showed a relatively high consistency at the family level with the diagnosis of two major subclades.

Systematics of the Eucestoda: advances toward a new phylogenetic paradigm, and observations on the early diversification of tapeworms and vertebrates

“…Ivanov & Hoberg (this volume) examined the problematical Diphyllidea and present a preliminary phylogeny at the species level for this enigmatic group. Rego et al (1998), presented a robust hypothesis for the Proteocephalidea that supports diagnosis of the subfamilies and monophyly of the Monticelliidae La Rue, 1911; historical biogeographic relationships centring on Gondwanaland are outlined. An hypothesis for relationships among the genera of tetraphyllidean, lecanicephalidean and diphyllidean tapeworms, based on a bottom-up analysis examining representative species and genera, was developed by Caira, Jensen & Healy (1999); this will be presented in a separate issue of Systematic Parasitology.…”

“…Phylogenetic resolution has now been obtained for inter-ordinal relationships among the eucestodes. During the 2nd IWTS, hypotheses varying in their degrees of resolution were developed for families, subfamilies or genera among seven of 12 recognised orders (Pseudophyllidea, Diphyllidea, Trypanorhyncha, "Tetraphyllidea", Lecanicephalidea, Proteocephalidea and Cyclophyllidea) (Beveridge et al, 1999;Bray et al, 1999;Caira et al, 1999;Ivanov & Hoberg, 1999;Rego et al, 1998). Prior to the Workshop, only the Tetrabothriidea (Hoberg, 1989;Hoberg & Adams, 1992) and the Proteocephalidea (Brooks, 1978;Brooks & Rasmussen, 1984) had been evaluated.…”

“…The diphyllideans, trypanorhynchs and the paraphyletic assemblage of the tetraphyllideans along with the lecanicephalideans are found exclusively in chondrichthians (Neoselachii, skates, rays and sharks). Proteocephalideans are found principally in Siluriformes (catfishes) but also other relatively basal freshwater teleosts; some proteocephalideans are known in amphibians, chelonians and lepidosaurians (Rego et al, 1998). Nippotaeniideans are parasites in basal teleosts (e.g.…”

Scolex Morphology of Proteocephalid Cestodes Parasites of Neotropical Freshwater Fishes

“…Rego (1995) proposed a radical solution, which was to eliminate the taxa Monticelliidae, and to accept only one family, Proteocephalidae, for the South American species, with two subfamilies, Corallobothriinae and Proteocephalinae, for the species with or without a metascolex. Rego et al (1998) published a cladistic analyses of proteocephalid subfamilies; the Monticelliid sufamilies were provisionally maintained, depending of further phylogenetic analyses of the South American genera. Hoberg et al (1997) evaluated the phylogeny of the Eucestoda.…”

“…Rego (1995) disagreed with this scheme of classification, and proposed the elimination of the Monticelliidae and its subfamilies, based in the fact that the actual classification is not suitable for the forms of proteocephalids recently described, which present intermediate characteristics, and others with inconspicuous longitudinal musculature, resulting the impossibility of the definition of the taxa they belong to. Rego et al (1998) carried a cladistic analysis based on comparative morphology, to examine the subfamily-level relationships within the order Proteocephalidea. The study did not evaluate relationships at the generic level, particularly those within the Monticelliidae (sensu Rego 1994).…”