Thylogale Stigmatica Research Articles

Occurrence patterns of sympatric forest wallabies: assessing the influence of structural habitat attributes on the coexistence of Thylogale thetis and T.stigmatica.

We studied the occurrence of two sympatric wallabies, the red-necked pademelon (Thylogale thetis) and the red-legged pademelon (T. stigmatica) in northeastern New South Wales, Australia in relation to structural habitat attributes. At our study site, both species inhabit closed forest environments and have overlapping distributions, but T. thetis leaves the forest at night to graze adjacent grassy forest edges whereas T. stigmatica remains within the forest and browses forest vegetation. The objectives of the study were to investigate how structural attributes of two forest types, wet sclerophyll forest and rainforest, relate to the fine-scale occurrence of these two wallaby species within the forested environment. We gathered occurrence data from 48 camera trap stations divided equally between rainforest and wet sclerophyll forest. At each camera point, we also measured a range of structural habitat attributes to determine habitat affiliations for the two Thylogale species. Principal component analyses were used to describe major trends in habitat, and generalised linear models were used to describe the efficacy of the variables in predicting habitat occurrence of each species. The number of occurrences of Thylogale thetis was significantly greater than occurrences of T. stigmatica, which was driven by significantly greater occurrences of T. thetis in wet sclerophyll forest. There was both spatial and temporal partitioning between the two species; there was a significant difference in the occurrences of the two species at individual cameras and T. stigmatica had a different activity schedule than T. thetis in wet sclerophyll forest, where the latter reached its greatest rate of occurrence. At a finer (camera station) scale, occurrences of T. thetis increased with proximity to roads and grassy edges and at sites that were less rocky and less steep. T. stigmatica occurrence increased in the presence of rainforest elements like vines, palms and ferns, more ground-level cover and tree-fall gaps and at sites with fewer emergent eucalypts. Our findings have implications for managing these pademelons and their habitats. T. thetis is a common species that was encountered more often than T. stigmatica, and it responded positively to human disturbance like roadsides and grassy edges, presumably because these areas provided good grazing opportunities. By comparison, T. stigmatica is a threatened species, and it responded to natural disturbance like tree-fall gaps where lateral cover was greater, and where rainforest food plants may be more abundant. Our results suggest, therefore, that conservation of the threatened T. stigmatica requires the preservation of intact rainforest.

Diet of the Dingo in Subtropical Australian Forests: Are Small, Threatened Macropods at Risk?

Carnivores fulfil important ecological roles in natural systems yet can also jeopardise the persistence of threatened species. Understanding their diet is, therefore, essential for managing populations of carnivores, as well as those of their prey. This study was designed to better understand the diet of an Australian apex predator, the dingo, and determine whether it poses a threat to at-risk small macropods in two floristically different yet geographically close reserves in subtropical Australia. Based on an analysis of 512 scats, dingo diets comprised 34 different prey taxa, of which 50% were common between reserves. Our findings add support to the paradigm that dingoes are opportunistic and generalist predators that prey primarily on abundant mammalian fauna. Their diets in the Border Ranges were dominated by possum species (frequency of occurrence (FOC) = 92.5%), while their diets in Richmond Range were characterised by a high prevalence of pademelon species (FOC = 46.9%). Medium-sized mammals were the most important dietary items in both reserves and across all seasons. The dietary frequency of medium-sized mammals was generally related to their availability (indexed by camera trapping); however, the avoidance of some species with high availability indicates that prey accessibility may also be important in dictating their dietary choices. Other prey categories were supplementary to diets and varied in importance according to seasonal changes in their availability. The diets included two threatened macropods, the red-legged pademelon and black-striped wallaby. Our availability estimates, together with earlier dietary studies spanning 30 years, suggest that the red-legged pademelon is resilient to the observed predation. The black-striped wallaby occurred in only two dingo scats collected from Richmond Range and was not detected by cameras so the threat to this species could not be determined. Two locally abundant but highly threatened species (the koala and long-nosed potoroo) were not detected in the dingoes' diets, suggesting dingoes do not at present pose a threat to these populations. Our study highlights the importance of site-based assessments, population monitoring and including data on prey availability in dietary investigations.

Activity patterns and temporal niche partitioning in sympatric red‐legged and red‐necked pademelons

AbstractTemporal partitioning between ecologically similar species facilitates co‐occurrence and can influence the structure of mammalian assemblages. We studied diel activity patterns of two sympatric forest‐dwelling wallabies, the red‐legged pademelon (Thylogale stigmatica) and red‐necked pademelon (Thylogale thetis) in eastern Australia to better understand spatiotemporal partitioning between these closely related macropods. Temporally, both species displayed strongly crepuscular activity patterns typical of many macropod species; however, compared with T. thetis, T. stigmatica was less active during evening twilight and more active in the period prior to dawn. Spatially, T. stigmatica used dense forest cover exclusively throughout the 24‐hour cycle, while T. thetis divided its habitat spatiotemporally, spending the diurnal period under forest cover and the nocturnal period on pasture beyond the forest edge. In practical terms, this meant that T. stigmatica and T. thetis were fully spatially segregated at night, during the period they would be likely to do most of their foraging. We propose that the spatiotemporal partitioning observed is niche partitioning, and provides a mechanism for the co‐occurrence of these closely related species.

Activity patterns and detection rates of red-legged pademelons (

Red-legged pademelons (Thylogale stigmatica) occur as several subspecies in eastern Australia. The northern subspecies (T. stigmatica stigmatica) in north Queensland is considered common; the southern subspecies (T. stigmatica wilcoxi) in north-eastern New South Wales is, by comparison, rare and is listed as threatened. Activity patterns should also vary between these subspecies because T. s. stigmatica emerges from the forest at night to graze, whereas T. s. wilcoxi remains in the forest throughout the 24-h cycle. Using camera traps, we detected pademelons at a greater rate at a Queensland site occupied by T. s. stigmatica than at a New South Wales site inhabited by T. s. wilcoxi; this result is consistent with their conservation status. However, pademelons at these sites displayed remarkably similar activity patterns within rainforest over the 24-h period, a result that was unexpected based on what is known of their diel behaviour.

Camera trap detection of mycophagy among co‐occurring vertebrates

AbstractThirty camera traps were deployed for a total of 4179 trap‐nights between January and June 2020 as part of a project assessing post‐fire recovery of pademelons (Thylogale spp.) in northern New South Wales. By chance, one camera documented a site that was highly productive for the ectomycorrhizal fungal genus Amanita. This camera provided a rare opportunity to document a diversity of co‐habitating vertebrates that utilise these ectomycorrhizal fungi for food and in turn perform an important ecosystem function through the dispersal of their spores. Our camera recorded eleven vertebrate species; of these, we captured photographic evidence of Australian brush‐turkeys (Alectura lathami), a parma wallaby (Notamacropus parma), long‐nosed bandicoots (Perameles nasuta), red‐legged pademelons (Thylogale stigmatica) and red‐necked pademelons (T. thetis) feeding on fungal fruiting bodies.

Short‐term response of threatened small macropods and their predators to prescribed burns in subtropical Australia

SummaryFire is an important ecological process that shapes vegetation structure and habitat for faunal assemblages globally. Prescribed burns are increasingly being used in conservation and management to restore fire regimes in fire‐suppressed vegetation communities. Small threatened macropods require structurally complex habitat that allows them to evade detection by predators. Given that fire can alter vegetation structure, it can be viewed as a strong ecological force in shifting the dynamics between predator and prey species. Previous studies in temperate Australia have shown that prescribed burns in the presence of European Red Fox (Vulpes vulpes) and feral Cat (Felis catus) can have negative impacts on small macropods and medium‐sized mammals. Post‐fire response of threatened small macropods and their predators has not been experimentally examined in subtropical Australia despite this region providing refugia for the Long‐nosed Potoroo (Potorous tridactylus) and Red‐legged Pademelon (Thylogale stigmatica). We conducted a before‐after‐control‐impact fire experiment at two paired sites after low–moderate intensity burns typical of cool season prescribed burns. We used camera trapping to investigate changes in activity of threatened small macropods and their predators. We also recorded vegetation change. Despite large reductions in ground and shrub cover, activity of small macropods and the Dingo (Canis dingo) did not change in response to fires. Therefore, the threat of dingo predation appears to have remained unchanged following the fires. Although feral cats and foxes were present, they showed negligible activity across our sites. Our study suggests that small‐scale patchy ecological burns may not lead to increased predation of small macropods in our landscape. We attribute this to sufficient post‐fire refugia and very low densities of foxes.

Habitat and introduced predators influence the occupancy of small threatened macropods in subtropical Australia.

Australia has had the highest rate of mammal extinctions in the past two centuries when compared to other continents. Frequently cited threats include habitat loss and fragmentation, changed fire regimes and the impact of introduced predators, namely the red fox (Vulpes vulpes) and the feral cat (Felis catus). Recent studies suggest that Australia's top predator, the dingo (Canis dingo), may have a suppressive effect on fox populations but not on cat populations. The landscape of fear hypothesis proposes that habitat used by prey species comprises high to low risk patches for foraging as determined by the presence and ubiquity of predators within the ecosystem. This results in a landscape of risky versus safe areas for prey species. We investigated the influence of habitat and its interaction with predatory mammals on the occupancy of medium‐sized mammals with a focus on threatened macropodid marsupials (the long‐nosed potoroo [Potorous tridactylous] and red‐legged pademelon [Thylogale stigmatica]). We assumed that differential use of habitats would reflect trade‐offs between food and safety. We predicted that medium‐sized mammals would prefer habitats for foraging that reduce the risk of predation but that predators would have a positive relationship with medium‐sized mammals. We variously used data from 298 camera trap sites across nine conservation reserves in subtropical Australia. Both dingoes and feral cats were broadly distributed, whilst the red fox was rare. Long‐nosed potoroos had a strong positive association with dense ground cover, consistent with using habitat complexity to escape predation. Red‐legged pademelons showed a preference for open ground cover, consistent with a reliance on rapid bounding to escape predation. Dingoes preferred areas of open ground cover whereas feral cats showed no specific habitat preference. Dingoes were positively associated with long‐nosed potoroos whilst feral cats were positively associated with red‐legged pademelons. Our study highlights the importance of habitat structure to these threatened mammals and also the need for more detailed study of their interactions with their predators.

Feeding Biomechanics Influences Craniofacial Morphology at the Subspecies Scale among Australian Pademelons (Macropodidae: Thylogale)

Interspecific variation in the craniofacial morphology of kangaroos and wallabies is associated with diet and feeding behaviors. Yet, to how fine a taxonomic scale this relationship might exist is unknown. Using a combination of established morphometric analyses and novel finite element approaches, we test the limits of these associations by examining three closely-related pademelon taxa: the red-necked pademelon (Thylogale thetis), and two subspecies of the red-legged pademelon (Thylogale stigmatica stigmatica and Thylogale stigmatica wilcoxi). All three taxa have distinct proportions of graze (grasses) and browse (leaves, stems, and branches of trees and shrubs) in their diets. We identified clear morphological differences in the crania between all three taxa and significant influences of geography and climate on cranial shape. We found significant differences in shape and strain magnitudes along the muzzle and cheek bones of each group that are consistent with the properties of their respective diets. These results suggest that feeding ecology influences craniofacial morphology down to the subspecies scale for at least some kangaroos and wallabies, which mirrors what is known at the macroevolutionary level for these species. This lends further weight to the predictive value of cranial morphology in determining feeding ecology among the Macropodiformes and may be of use in inferring feeding ecology of less accessible species for conservation and management.

Pharyngostrongylus thylogale n. sp. (Nematoda: Strongylida) from the stomachs of macropodid marsupials defined by morphological and molecular criteria.

Pharyngostrongylus thylogale n. sp. (Nematoda: Strongylida) is described from the stomach of the red-legged pademelon, Thylogale stigmatica (Gould) (Marsupialia: Macropodidae) from north-eastern Queensland and Papua New Guinea, having formerly been confused with P. iota Johnston & Mawson, 1939. Pharyngostrongylus thylogale n. sp. differs from all congeners in having 12 labial crown elements rather than eight or 16. Pharyngostrongylus iota was found in T. stigmatica, but only in southern Queensland and northern New South Wales, in the subspecies T. s. wilcoxi, compared with P. thylogale n. sp. which was found in T. s. stigmatica in northern Queensland and T. s. oriomo in Papua New Guinea. Differences in the sequences of the first and second internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA of P. thylogale n. sp. and ten congeners support the erection of the new species, and the validity of the morphospecies examined. However, results of the phylogenetic analyses of the molecular data also provide evidence for the existence of cryptic species within P. kappa Mawson, 1965. No obvious co-evolutionary relationships were observed between parasite species and their macropodid marsupial hosts.

Horizontal or vertical? Camera trap orientations and recording modes for detecting potoroos, bandicoots and pademelons

Camera traps can detect rare and cryptic species, and may enable description of the stability of populations of threatened species. We investigated the relative performance of cameras oriented horizontally or vertically, and recording mode (still and video) to detect the vulnerable long-nosed potoroo (Potorous tridactylus) as a precursor to population monitoring. We established camera traps for periods of 13–21 days across 21 sites in Richmond Range National Park in north-east New South Wales. Each camera trap set consisted of three KeepGuard KG680V cameras directed at a bait container – one horizontal and one vertical camera in still mode and one horizontal camera in video mode. Potoroos and bandicoots (Perameles nasuta and Isoodon macrourus) were detected at 14 sites and pademelons (Thylogale stigmatica and T. thetis) were detected at 19 sites. We used program Presence to compare detection probabilities for each camera category. The detection probability for all three taxa groups was lowest for the vertical still and similar for the horizontal cameras. The detection probability (horizontal still) was highest for the potoroos (0.43) compared with the bandicoots (0.16) and pademelons (0.25). We estimate that the horizontal stills camera could achieve a 95% probability of detection of a potoroo within 6 days compared with 8 days using a vertical stills camera. This suggests that horizontal cameras in still mode have great potential for monitoring the dynamics of this potoroo population.

Improving reliability of scat counts for abundance and distribution estimations of Lumholtz’s Tree-kangaroo (Dendrolagus lumholtzi) in its rainforest habitats.

arboreal folivores, such as Lumholtz’s Tree-kangaroo (Dendrolagus lumholtzi) in Far North Queensland, Australia, scat counts seem to be the most promising ecological technique. However, the occurrence of Lumholtz’s Tree-kangaroos in seasonal rainforests with dense understory, a high diversity of coprophagous invertebrates and with sympatric folivores increases the probability of invalidating results based on scat surveys. This study investigates scat production and scat decomposition patterns to select diagnostic traits of Lumholtz’s Tree-kangaroo scats that can, under varying environmental conditions, assist in distinguishing between fresh and old scats to reduce false positive and false negative errors in species presence due to non- or/and misidentification of scats. Scat production rates of six captive Lumholtz’s Tree-kangaroos were highly variable resulting in different scat numbers and masses. Changes in scat size (mass and circumference), pH and the appearance of mould were monitored under different laboratory conditions and in forest trials. Under wet conditions scats gained mass until they reached an apparent plateau of 130% of their original mass. Scats under dry conditions lost up to 90% of their original mass. Changes in mass were accompanied by changes in circumference of scats. By Day 3 scats had developed signs of mould under laboratory conditions and showed an acidic pH. Field trials revealed a high loss of scats due primarily to their consumption by dung beetles (Scarabaeoidea). For studying Lumholtz’s Tree-kangaroos in their rainforest environment, scat surveys should be confined to dry periods to reduce the probability of false negative errors due to activity of coprophagous invertebrates. Additionally, only fresh scats of average size and with an acidic pH should be used to minimize the risk of misidentifying small sized scats from Red-legged Pademelons (Thylogale stigmatica) as tree-kangaroo scats. More studies on species-specific diagnostic traits of Lumholtz’s Tree-kangaroo scats are necessary to validate false negative and false positive errors in scat counts for this species.

Effects of historical forest contraction on the phylogeographic structure of Australo-Papuan populations of the red-legged pademelon (Macropodidae: Thylogale stigmatica)

Geographic patterns of genetic variation are strongly influenced by historical changes in species habitats. Whether such patterns are common to co-distributed taxa may depend on the extent to which species vary in ecology and vagility. We investigated whether broad-scale phylogeographic patterns common to a number of small-bodied vertebrate and invertebrate species in eastern Australian forests were reflected in the population genetic structure of an Australo-Papuan forest marsupial, the red-legged pademelon (Macropodidae: Thylogale stigmatica). Strong genetic structuring of mtDNA haplotypes indicated the persistence of T. stigmatica populations across eastern Australia and southern New Guinea in Pleistocene refugial areas consistent with those inferred from studies of smaller, poorly dispersing species. However, there was limited divergence of haplotypes across two known historical barriers in the northeastern Wet Tropics (Black Mountain Barrier) and coastal mideastern Queensland (Burdekin Gap) regions. Lack of divergence across these barriers may reflect post-glacial recolonization of forests from a large, central refugium in the Wet Tropics. Additionally, genetic structure is not consistent with the present delimitation of subspecies T. s. wilcoxi and T. s. stigmatica across the Burdekin Gap. Instead, the genetic division occurs further to the south in mideastern Queensland. Thus, while larger-bodied marsupials such as T. stigmatica did persist in Pleistocene refugia common to a number of other forest-restricted species, species-specific local extinction and recolonization events have resulted in cryptic patterns of genetic variation. Our study demonstrates the importance of understanding individualistic responses to historical climate change in order to adequately conserve genetic diversity and the evolutionary potential of species.

Two New Species Of Filarinema Mönnig, 1929 (Nematoda: Trichostrongylina) Parasitic In Macropodid Marsupials

Two new species of Filarinema Mönnig, 1929 (Nematoda: Trichostrongylina) are described from the pyloric antrum of kangaroos. Filarinema occidentale sp. nov. from the stomach of the red kangaroo, Macropus rufus (Desmarest, 1822) from Western Australia is distinguished from most congeners in having both the dorsal and ventral internal branches of the spicules sharp-tipped. The spicules of F. occidentale are much longer than those of the most closely related species F. asymmetricum (Cameron, 1926). Filarinema thylogale sp. nov. from the stomach of the red-legged pademelon, Thylogale stigmatica (Gould, 1860) from northern Queensland is distinguished from all congeners in the shape of the spicules bearing a claw-like distal termination of the principal branch. Macropus rufus and M. fuliginosus (Desmarest, 1817) are reported as new hosts for F. dissimile (Wood, 1931).

Long‐Term Dynamics of a Fragmented Rainforest Mammal Assemblage

Habitat fragmentation is a severe threat to tropical biotas, but its long-term effects are poorly understood. We evaluated longer-term changes in the abundance of larger (>1 kg) mammals in fragmented and intact rainforest and in riparian "corridors" in tropical Queensland, with data from 190 spotlighting surveys conducted in 1986-1987 and 2006-2007. In 1986-1987 when most fragments were already 20-50 years old, mammal assemblages differed markedly between fragmented and intact forest. Most vulnerable were lemuroid ringtail possums (Hemibelideus lemuroides), followed by Lumholtz's tree-kangaroos (Dendrolagus lumholtzi) and Herbert River ringtail possums (Pseudocheirus herbertensis). Further changes were evident 20 years later. Mammal species richness fell significantly in fragments, and the abundances of 4 species, coppery brushtail possums (Trichosurus vulpecula johnstoni), green ringtail possums (Pseudochirops archeri), red-legged pademelons (Thylogale stigmatica), and tree-kangaroos, declined significantly. The most surprising finding was that the lemuroid ringtail, a strict rainforest specialist, apparently recolonized one fragment, despite a 99.98% decrease in abundance in fragments and corridors. A combination of factors, including long-term fragmentation effects, shifts in the surrounding matrix vegetation, and recurring cyclone disturbances, appear to underlie these dynamic changes in mammal assemblages.

Hypogeous fungi in the diet of the red-legged pademelonThylogale stigmaticafrom a rainforest-open forest interface in northeastern Australia

The diet of the Red-legged Pademelon Thylogale stigmatica has previously been described as comprising a range of dicotyledonous and monocotyledonous plants, rainforest fruits, seeds, and some fungi. We collected T. stigmatica faecal samples from a rainforest-open forest ecotone in northeastern Australia and analysed them for the presence of fungal spores. Of the 20 samples collected, 12 contained spores of several types of hypogeous fungi, with the number of spore types per sample ranging from 1-7, with a mean of 5. Twenty fungal spore types were recognised in total; seven of these could be attributed to hypogeous (‘truffle-like’) ectomycorrhizal genera, and most others had spore morphologies suggestive of a hypogeous habit. This is the first report of consumption of ectomycorrhizal hypogeous fungi by the genus Thylogale, and as such, adds important new information on the role these forest-dwelling wallabies might play in dispersing hypogeous fungi across the dynamic interface between rainforest and open ...

Revision of the Progamotaenia zschokkei (Janicki, 1905) complex (Cestoda: Anoplocephalidae), with the description of six new species

A review of cestodes currently attributed to Progamotaenia zschokkei (Janicki, 1905) (Cestoda: Anoplocephalidae) suggests that six additional species are present: Pr. tenuis n. sp. found in Thylogale stigmatica (Gould) and T. thetis (Lesson), Pr. lomatosoma n. sp.from Macropus agilis (Gould), Pr. petrogale n. sp. from Petrogale spp. and Macropus dorsalis(Grey), Pr. fimbriata n.s p. from Lagorchestes conspicillatus Gould and L. hirsutus Gould, Pr. obesa n. sp. from Onychogalea fraenata (Gould) and O. unguifera (Gould) in north-eastern Australia and Pr. kellerae n. sp. from O. unguifera in north-western Australia. The new species are differentiated by a combination of characters: prominence of scolex lobes, number of lobes in the fimbriated velum, testis number and distribution, size of the cirrus-sac, morphology of the uterus and presence or absence of a pyriform apparatus in eggs from terminal segments. The morphological differences found support earlier molecular studies, in that cestodes within each host genus are distinct, with the exception that considerable morphological variation exists within Pr. petrogale. Principal components analysis suggested that most of the cestodes from Petrogale spp. belonged to Pr. petrogale. The status of specimens from Pe. lateralis is unclear. More detailed molecular studies are required to determine the significance of the morphological variation within this taxon. A key is provided to species within the complex and the related species Pr. villosa (Lewis, 1914).

New Host Records, Redescriptions and New Species of Labiostrongylinea (Nematoda: Chabertiidae) from Macropodid Marsupials, with a Revised Host-Parasite Checklist

SummaryNew host records: from Macropus rufogriseus for Labiosimplex clelandi, M. robustus for Ls. aridus, Thylogale stigmatica for Ls. thetidis, and M. parma for Ls. bancrofti are reported. On re-examination of all material, Labiosimplex quasibancrofti was found to be morphologically indistinguishable from Ls. australis and is therefore a synonym of Ls. australis. A new species of Labiomultiplex, described from a single female from M. parma, is differentiated by the shape of the lateral lips and Lm. kimberleyensis is redescribed from additional material collected from the type-host, Onychogalea fraenata, from Queensland. Two new species of Labiosimplex are described from macropodid marsupials from central Australia. Labiosimplex centralis sp. nov. from the stomach of Petrogale lateralis differs from the most similar of its congenors, Ls. thomasae (both lacking a gubernaculum), in having shorter spicules, a shorter dorsal lobe of the bursa, and in the form of the dorsal ray. Labiosimplex territoriensis sp. nov. from the stomach of M. antilopinus differs from all its congenors in having large multi-lobed oesophago-intestinal diverticula. A new species, Labiostrongylus arnhemensis sp. nov. from the stomach of M. bernardus from the Northern Territory, differs from its congenors in a suite of characters including the position of the deirids, the shape of the oesophago-intestinal diverticula, the length of the dorsal lobe of the bursa, the morphology of the genital cone and gubernaculum and the length of the female tail. A revised host-parasite checklist, including Labiostrongylinea from the island of New Guinea together with those occurring in Potoroidae, is given.

Genetic variation in the mitochondrial cytochrome c oxidase subunit 1 within three species of Progamotaenia (Cestoda: Anoplocephalidae) from macropodid marsupials

Sequence variation within 3 morphologically defined species of the anoplocephalid cestode genus Progamotaenia (P. ewersi, P. macropodis and P. zschokkei) was investigated using the cytochrome c oxidase subunit 1 gene. The magnitude of genetic variation detected within each morphospecies suggests that, in each instance, several cryptic species are present. Within P. ewersi, 5 genetically distict groups of cestodes were detected, 1 shared by Macropus robustus and M. parryi in Queensland, 1 in M. agilis from Queensland, 1 in Petrogale assimilis from Queensland, 1 in Macropus fuliginosus from South Australia and 1 in Wallabia bicolor from Victoria. In P. macropodis, cestodes from M. robustus from Queensland, Western Australia and the Northern Territory, M. parryi from Queensland and M. eugenii from South Australia were genetically distinct from those in Wallabia bicolor from Queensland and Victoria and from M. fuliginosus from South Australia. P. zschokkei consisted of a number of genetically distinct groups of cestodes, 1 in Lagorchestes conspicillatus and L. hirsutus from Queensland and the Northern Territory respectively, 1 in Petrogale herberti, P. assimilis and M. dorsalis from Queensland, 1 in Onychogalea fraenata from Queensland, 1 in M. agilis from Queensland and 1 in Thylogale stigmatica and T. thetis from Queensland. In general, genetic groups within each morphospecies were host specific and occurred predominantly in a particular macropodid host clade. Comparison of genetic relationships of cestodes with the phylogeny of their hosts revealed examples of colonization (P. zschokkei in M. agilis) and of host switching (P. zschokkei in M. dorsalis).

Sutarostrongylus Johnsoni sp. n. (Nematoda: Trichostrongylina, Heligmosomoidea) from the pademelon, Thylogale stigmatica (Marsupialia) from Queensland, Australia.

A new species of heligmosomoid nematode Sutarostrongylus johnsoni sp. n., belonging to the sub-family Herpetostrongylinae Skrjabin & Schultz, is described from the small intestine (duodenum) of the red-legged pademelon, Thylogale stigmatica (Gould, 1860) (Marsupialia: Macropodidae), from north-eastern Queensland, Australia. The only other species of the genus S. kirkpatricki Beveridge & Durelte-Desset, 1986 occurs in the related host, the red-necked pademelon, T. thetis (Lesson, 1827) in south-eastern Queensland. The new species differs in having longer spicules and asymmetrical spicule tips as well as the presence of a comârete which develops on the right ventral aspect of the mid-region of the body. The synlophe of the new species is unusual in that the inclination of the axis of orientation changes from being oblique in the anterior part of the body to being frontal in the posterior part. The same change may occur in some species of Austrostrongylus Chandler, 1924. Current data suggest that species of Sutarostrongylus are limited to a single genus of host, Thylogale Gray, 1837 and support the suggestion that both nematode species exhibit morphological features which are intermediate between those occurring in Herpetotostrongylinae in dasyurid marsupials and those occurring in macropodid marsupials.

Revision of Coronostrongylus (Nematoda : Strongyloidea) parasitic in the stomachs of macropodid marsupials

The monotypic nematode genus Coronostrongylus Johnston & Mawson, 1939 from the stomachs of macropodid marsupials was reviewed and was found to consist of a least seven closely related species. Coronostrongylus coronatus Johnston & Mawson, 1939 is found most commonly in Macropus rufogriseus, but occurs occasionally in M. dorsalis, M. parryi and Petrogale inornata. Coronostrongylus johnsoni, sp. nov. is most commonly found in M. dorsalis, but occurs also in M. rufogriseus, M. parma, Thylogale stigmatica, Petrogale godmani and P. brachyotis. Coronostrongylus barkeri, sp. nov. is most prevalent in Onychogalea unguifera, but occurs also in M. rufus, M. robustus and P. brachyotis. Coronostrongylus closei, sp. nov. is restricted to Petrogale persephone. Coronostrongylus sharmani, sp. nov. occurs only in rock wallabies from eastern Australia: P.�coenensis, P. godmani and P. mareeba; C. spratti, sp. nov. occurs in P. inornata and P. assimilis. Coronostrongylus spearei, sp. nov. is restricted to Papua New Guinea where it is found in Dorcopsulus vanhearni, Dorcopsis hageni and D. muelleri. Although all of the nematode species occur in one principal host species or a series of closely related host species, occurrences in geographically disjunct areas and in phylogenetically distant hosts are features of C. coronatus, C. barkeri, sp. nov. and C. johnsoni, sp. nov. The occurrence of seven closely related nematode species found in a wide range of macropodid host species is more readily accounted for by a hypothesis involving multiple colonisations of hosts than by the hypothesis of co-speciation.