A new tetraphyllidean genus and species, Caulopatera pagei n. g., n. sp. (Tetraphyllidea: Phyllobothriidae), from the grey carpetshark Chiloscyllium punctatum Müller & Henle (Orectolobiformes: Hemiscylliidae)

Abstract

A new genus and species of tetraphyllidean cestode, Caulopatera pagei n. g., n. sp., is described from the grey carpetshark Chiloscyllium punctatum Müller & Henle in Moreton Bay, Australia. The new genus is placed in the Phyllobothriidae, subfamily Phyllobothriinae. Caulopatera n. g. is distinct from all other phyllobothriine genera in having stalked, circular, non-loculate bothridia that lack an apical sucker, testes that are restricted to the region anterior to the cirrus-sac and circum-medullary vitelline follicles. The new genus most closely resembles Carpobothrium Shipley & Hornell, 1906, with which it shares non-loculate, stalked, unhooked bothridia without an accessory sucker and testes that are entirely anterior to the cirrus-sac, but differs from it in that it lacks a slit-like opening in each bothridium and flaps surrounding the opening. The possession of bothridial stalks is consistent with two cestode orders, the Tetraphyllidea and the Rhinebothriidea. The morphology of the bothridial stalks is consistent with other tetraphyllidean genera, in that Caulopatera possesses triangular bothridial stalks surrounding the back of the bothridia, indicating that it belongs in the Tetraphyllidea senso stricto, rather than in the recently recognised Rhinebothriidea.

Diversity and phylogenetic relationships of 'tetraphyllidean' Clade 3 (Cestoda) based on new material from orectolobiform sharks in Australia and Taiwan

“…The tree resulting from the analysis indicates that Ambitalveolus is the earliest diverging lineage of Clade 3. The grouping of Caulopatera and Carpobothrium as sister taxa supports the hypothesis advanced by Cutmore et al (2010), and later endorsed by Caira et al (2017) when establishing Clade 3, that these genera are close relatives. Within Carpobothrium, the earliest diverging species is Carpobothrium megaphallum from Chiloscyllium griseum.…”

“…Of the seven species of Chiloscyllium examined for cestodes to date (see Caira et al 2021b), this genus has only ever been reported from the undescribed species Chiloscyllium cf. punctatum in Moreton Bay, Australia (Cutmore et al 2010). Nonetheless, in the absence of other data, the species of Chiloscyllium that have not yet been examined for cestodes would seem to be the most viable candidates as hosts for other species of Caulopatera.…”

“…Although in bearing circular bothridia the new genus resembles Caulopatera, it conspicuously differs from Caulopatera in that its vitelline follicles are arranged in two lateral bands, rather than being circum-medullary, and its genital pore is in the posterior, rather than anterior, half of the proglottid. Moreover, the bothridia of Caulopatera were described as lacking marginal loculi by Cutmore et al (2010), but the new genus bears conspicuous marginal loculi throughout the entire circumference of its bothridia. 3D); distal surface of bothridial rim covered with acicular filitriches (Fig.…”

“…To explore the phylogenetic relationships among these taxa we generated sequence data for the D1-D3 region of the 28S rRNA gene de novo for one to three specimens of each of the four described and one undescribed species of Carpobothrium, as well as for one specimen of Caulopatera pagei Cutmore, Bennett et Cribb, 2010 and two speci-mens of the new species from O. japonicus. The result was the first phylogenetic tree of the relationships among members of Clade 3.…”