Torquenema n. g., Wallabicola n. g., and Macropostrongyloides phascolomys n. sp.: New Genera and a New Species of Nematode (Strongylida: Phascolostrongylinae) Parasitic in Australian Macropodid and Vombatid Marsupials

Tanapan Sukee,Ian Beveridge,Abdul Jabbar

doi:10.3390/ani11010175

Abstract

Simple SummaryThis article describes two new genera of parasitic nematodes, Torquenema n. g. from the eastern grey kangaroo and Wallabicola n. g. from the swamp wallaby, and a new species, Macropostrongyloides phascolomys n. sp. from the caecum of the common wombat. The strongyloid nematodes belonging to the subfamily Phascolostrongylinae occur primarily in the large intestines of macropodid and vombatid marsupials. Current molecular evidence suggests that the two nematode species, Macropostrongyloides dissimilis and Paramacropostrongylus toraliformis, from macropodid marsupials are distant from their respective congeners. Furthermore, specimens of Macropostrongyloides lasiorhini from the large intestines of the southern hairy-nosed wombat (Lasiorhinus latifrons) and the common wombat (Vombatus ursinus) are genetically distinct. This study aimed to describe the new genera Torquenema n. g. (with T. toraliforme n. comb. as the type species) from the eastern grey kangaroo, Wallabicola n. g. (with W. dissimilis n. comb. as the type species) from the swamp wallaby and a new species Macropostrongyloides phascolomys n. sp. from the common wombat, using light and scanning electron microscopy.

Highlights

The strongyloid nematode subfamily, Phascolostrongylinae Lichtenfels, 1980 is currently represented by seven genera and 19 species found in kangaroos, wallabies, and wombats (Macropodidae and Vombatidae) [1]
One of the tribes is the Macropostrongyloidinea, which comprises the genera Macropostrongyloides Yamaguti, 1961 and Paramacropostrongylus Johnston and Mawson, 1940, and they are generally characterised by small cylindrical buccal capsules with a distinctive Y-shaped dorsal gutter and the presence of peri-oral teeth or denticles [1]
The majority of species within the Phascolostrongylinae are restricted to the large intestines of their hosts, several exceptional species, all belonging to the tribe Macropostrongyloidinea, have been found within the stomachs of macropodid marsupials [2]

Summary

Introduction

The strongyloid nematode subfamily, Phascolostrongylinae Lichtenfels, 1980 is currently represented by seven genera and 19 species found in kangaroos, wallabies, and wombats (Macropodidae and Vombatidae) [1]. One of the tribes is the Macropostrongyloidinea, which comprises the genera Macropostrongyloides Yamaguti, 1961 and Paramacropostrongylus Johnston and Mawson, 1940, and they are generally characterised by small cylindrical buccal capsules with a distinctive Y-shaped dorsal gutter and the presence of peri-oral teeth or denticles [1]. A recent molecular study based on the first and second internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA revealed that the genera Macropostrongyloides and Paramacropostrongylus were paraphyletic, with Macropostrongyloides dissimilis. The study found that M. dissimilis, a dark-red nematode from the stomach of the swamp wallaby Wallabia bicolor (Desmarest) is a sister taxon to the only other stomach-inhabiting phascolostrongyline species Paramacrop-

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