Search

Anoplotaenia dasyuriBeddard, 1911 (Cestoda), from the Tasmanian devil,Sarcophilus harrisii(Boitard, 1842), is a taxonomic enigma, where a combination of morphological features, host type and geographical location have prevented it from being placed within a family and it is consideredincertae sedis, despite its accepted validity. We performed a phylogenetic analysis of threeA. dasyurispecimens collected from three Tasmanian devils using 18S and 28S rRNA sequences.Anoplotaenia dasyuriwas found to have closest affinity with the family Paruterinidae, especially the genusCladotaeniaCohn, 1901. The postulated theory of transfer of an ancestor ofAnoplotaeniaBeddard, 1911 transferring to the Tasmanian devil from an unrelated carnivorous host, such as an accipitriform or other carnivorous bird, is discussed and supported.

Anoplotaenia dasyuri Beddard, 1911 (Cestoda), from the Tasmanian devil, Sarcophilus harrisii (Boitard, 1842), is a taxonomic enigma, where a combination of morphological features, host type and geographical location have prevented it from being placed within a family and it is considered incertae sedis, despite its accepted validity. We performed a phylogenetic analysis of three A. dasyuri specimens collected from three Tasmanian devils using 18S and 28S rRNA sequences. Anoplotaenia dasyuri was found to have closest affinity with the family Paruterinidae, especially the genus Cladotaenia Cohn, 1901. The postulated theory of transfer of an ancestor of Anoplotaenia Beddard, 1911 transferring to the Tasmanian devil from an unrelated carnivorous host, such as an accipitriform or other carnivorous bird, is discussed and supported.

SUMMARYThe acanthocephalan fauna of Australian freshwater fishes was documented from field surveys, a literature survey and examination of specimens registered in Australian museums. From the 4030 fishes, representing 78 of the 354 Australian freshwater fish species (22%), examined for infection seven species of acanthocephalan were recovered. These species comprised five endemic species, three in endemic genera, two species in cosmopolitan genera, one species not fully identified and 1 putative exotic species recovered from eight species of fish. Of theseEdmonsacanthus blairifromMelanotaenia splendida,was the only acanthocephalan found at a relatively high prevalence of 38·6%. These findings are indicative of a highly endemic and possibly depauperate acanthocephalan fauna. Species richness was higher in the tropical regions than the temperate regions of the country. Exotic acanthocephalan species have either not been introduced with their exotic hosts or have been unable to establish their life cycles in Australian conditions. Consequently, acanthocephalans have not yet invaded endemic Australian fish hosts.

SUMMARYGenetic variation was examined in the anoplocephalid cestode Progamotaenia festiva, from Australian marsupials, in order to test the hypothesis that P. festiva, is a complex of sibling species and to assess the extent of host switching reported previously based on multilocus enzyme electrophoresis (MEE). Polymerase chain reaction (PCR)-based single-strand conformational polymorphism (SSCP) was used for the analysis of sequence variation in the cytochrome c oxidase subunit 1 (cox1) gene among 179 specimens of P. festiva (identified based on morphology and predilection site in the host) from 13 different host species, followed by selective DNA sequencing. Fifty-three distinct sequence types (haplotypes) representing all specimens were defined. Phylogenetic analyses of these sequence data (utilizing maximum parsimony and neighbour-joining methods) revealed 12 distinct clades. Other heterologous species, P. ewersi and P. macropodis, were used as outgroups and the remaining bile-duct inhabiting species, P. diaphana and P. effigia, were included in the analysis for comparative purposes. The latter 2 species were nested within the clades representing P. festiva. Most clades of P. festiva identified were restricted to a single host species; one clade primarily in Macropus robustus was also found in the related host species M. antilopinus in an area of host sympatry; another clade occurring primarily in M. robustus occurred also in additional kangaroo species, M. rufus and M. dorsalis. High levels of genetic divergence, the existence of distinct clades and their occurrence in sympatry provide support for the hypothesis that P. festiva represents a complex of numerous species, most of which, but not all, are host specific. Three distinct clades of cestodes were found within a single host, M. robustus, but there was no evidence of within-host speciation.