Phylogenetic Relationships within the Nematode Subfamily Phascolostrongylinae (Nematoda: Strongyloidea) from Australian Macropodid and Vombatid Marsupials.

Tanapan Sukee,Abdul Jabbar,Ian Beveridge,Ahmad Jawad Sabir

doi:10.3390/microorganisms9010009

Tanapan Sukee, Abdul Jabbar + Show 2 more

Open Access

https://doi.org/10.3390/microorganisms9010009

Copy DOI

Journal: Microorganisms	Publication Date: Dec 22, 2020
Citations: 5	License type: CC BY 4.0

Affiliation: University of Melbourne

Abstract

The strongyloid nematode subfamily Phascolostrongylinae comprises parasites of the large intestine and stomach of Australian macropods and wombats. In this study, we tested the phylogenetic relationships among the genera of the Phascolostrongylinae using the first and second internal transcribed spacers of the nuclear ribosomal DNA. Monophyly was encountered in the tribe Phascolostrongylinea comprising two genera, Phascolostrongylus and Oesophagostomoides, found exclusively in the large intestine of wombats. The tribe Hypodontinea, represented by the genera Hypodontus and Macropicola from the ileum and large intestine of macropods, was also found to be monophyletic. The tribe Macropostrongyloidinea, comprising the genera Macropostrongyloides and Paramacropostrongylus, was paraphyletic with the species occurring in the stomach grouping separately from those found in the large intestines of their hosts. However, Macropostrongyloides dissimilis from the stomach of the swamp wallaby and Paramacropostrongylus toraliformis from the large intestine of the eastern grey kangaroo were distinct from their respective congeners. This study provided strong support for the generic composition of the tribe Phascolostrongylinea. The unexpected finding of M. dissimilis and P. toraliformis being distantly related to their respective congeners suggests a requirement for future taxonomic revision that may warrant separation of these species at the generic level.

Highlights

Australian macropodid (Family Macropodidae) and vombatid (Family Vombatidae) marsupials are parasitised by a diverse array of strongyloid nematodes that are classified in the subfamilies Cloacininae and Phascolostrongylinae [1]
Subsequent to quality trimming and sequence alignment, two unique sequences were generated each for P. toraliformis, P. typicus, P. iugalis, Ph. turleyi, O. giltneri and O. stirtoni, and one for O. longispicularis and M. ocydromi (Table 1)
The concatenated into subset 1 (ITS-1) and ITS-2 (ITS+) sequence variation among different species ranged from 0.20–34% (Table 3)

Summary

Introduction

Australian macropodid (Family Macropodidae) and vombatid (Family Vombatidae) marsupials are parasitised by a diverse array of strongyloid nematodes that are classified in the subfamilies Cloacininae and Phascolostrongylinae [1]. The subfamily Cloacininae is found exclusively in the oesophagus and stomach of macropods (kangaroos and wallabies) [2]. This subfamily has been the focus of previous morphological and molecular studies due to their extensive diversity, high prevalence and large burden of nematodes present in the hosts [2]. The subfamily Phascolostrongylinae is currently composed of seven genera found in macropodid and vombatid marsupials. Some of the genera possess unusual morphological features, which may have contributed to difficulties in previous taxonomic revisions [3,4]

Methods

Results

Discussion

Conclusion