Hemipristicola gunterae gen. n., sp. n. (Cestoda: Tetraphyllidea: Phyllobothriidae) from the snaggletooth shark, Hemipristis elongata (Carcharhiniformes: Hemigaleidae), from Moreton Bay, Australia.

Abstract

Helminthological examination of the snaggletooth shark, Hemipristis elongata (Klunzinger) (Carcharhiniformes: Hemigaleidae), from Moreton Bay, Queensland, Australia, yielded a phyllobothriid genus and species previously unknown to science. Hemipristicola gunterae gen. n., sp. n. is described here, and is placed in the subfamily Phyllobothriinae Braun, 1900. Of the other phyllobothriid genera, the new genus most closely resembles Paraorygmatobothrium in that both genera possess bothridia with a single loculus and apical sucker, post-vaginal testes and lateral vitellarium. Hemipristicola, however, differs from Paraorygmatobothrium in the morphology of the proximal bothridial surface microthrix, possessing serrate gladiate spinitriches with marginal serrations restricted to the distal half of the blade, and in the possession of a more extensive uterus, extending anteriorly from the anterior margin of the ovary to well past the level of the cirrus-sac. The new genus also differs from Paraorygmatobothrium by possessing testes that are more than one layer deep. Hemipristicola gunterae further differs from Paraorygmatobothrium species found in hemigaleid sharks in possessing vitelline follicles arranged in two lateral bands that are restricted to the lateral margins of the proglottid and not possessing a cephalic peduncle. Bayesian inference analysis of partial 28S rDNA data shows that H. gunterae forms a sister taxon to species of Paraorygmatobothrium. These two genera were resolved with high posterior probability support in the analysis. Hemipristicola gunterae is only the second phyllobothriid species to be described from Hemipristis elongata from Australian waters, and the fourth from the Australian hemigaleids.