A survey of the helminths of Rattus sordidus, the canefield rat, together with a description of Ancistronema coronatum n. g., n. sp. (Nematoda: Chabertiidae)

Abstract

The digestive systems of 86 canefield rats from Ingham, Queensland were examined for parasites. One species of cestode and seven species of nematode were found, all but one being new host records. The helminth community was characterised in terms of core, secondary and satellite species. No core species were identified, but Nippostrongylus typicus and Odilia emanuelae were identified as secondary species. All other species were identified as satellite species. The strongyloid nematode Ancistronema coronatum n. g., n. sp. is described. Ancistronema differs from other genera in the Chabertiidae in having a short buccal capsule and in the number and shape of the elements of the internal and external leaf crowns. This is the first record of a strongyle from Australian rodents. It is postulated that it came into Australia with ancestral Rattus sp. hosts which colonised Australia from Indonesia less than a million years ago.

Syphacia (Syphacia) sulawesiensisn. sp. andS. (S.) muris(Yamaguti 1935) (Nematoda Oxyuridae) collected fromRattus xanthurus(Gray 1867) (Rodentia Muridae) in North Sulawesi, Indonesia

“…Apparently, its worldwide distribution has occurred with human facilitation of the dispersal of these commensal rats. This parasite has also been recorded from some endemic Rattus of Australia (HuGOT & QUENTIN 1985, SMALES 1992. However, it may be difficult to decide whether S. muris in these hosts has been maintained within the endemic rat colonies for long time or has been simply acquired from the commensal rats that arrived relatively recently.…”

Revision of the genera of Heligmonellidae (Nematoda, Heligmosomoidea), parasitic in Muridae from New Guinea

“…The genus Nippostrongylus was proposed by Durette-Desset et al [9] to be Asiatic in origin, reaching Australia with migrating Rattus spp. The finding, in New Guinea, of N. sembeli in old endemic hosts and also of N. magnus primarily described in old and new endemics from Australia [23,24], supports an Asiatic origin of the genus, with processes of host switching and speciation following migration, as suggested by Smales [34]. These host relationships and geographic distributions also support host migration across the Torres Strait from Australia to New Guinea as the origin of the presence of N. magnus in New Guinea as stated by Smales & Spratt [46].…”

“…Odilia emanuelae (Mawson, 1961), originally described from the Australian Rattus fuscipes , R. sordidus [ 19 , 23 ], R. leucopus [ 46 ] and Melomys cervinipes [ 48 ], was reported in New Guinea from Hyomys dammermani and Hyomys goliath [ 27 ], Pseudohydromys germani ( = Mayermis ellermani ) and Parahydromys asper [ 28 ].…”

The helminth parasites of Melomys cervinipes (Rodentia : Muridae : Hydromyinae)

“…The only other population of Australian rodents that has been studied, 86 Rattus sordidus examined from Ingham, northern Queensland, with a helminth community comprising one cestode and seven nematode species (Smales 1992), had a species richness similar to that for Whitsunday Island with one cestode, one trematode and 6 nematode species.…”