Pseudantechinus mimulus (Thomas, 1906)

Russell A. Mittermeier & Don E. Wilson, 2015, Dasyuridae, Handbook of the Mammals of the World – Volume 5 Monotremes and Marsupials, Barcelona: Lynx Edicions, pp. 232-348 : 296

12.

Carpentarian Pseudantechinus

Pseudantechinus mimulus

French: Dasyure des termitieres / German: Kleine Fettschwanz-Beutelmaus / Spanish: Falso antequino de Carpentaria

Other common names: Alexandria False Antechinus, Carpentarian Antechinus

Taxonomy. Phascogale mimulus Thomas, 1906 ,

near Alexandria (19° 03’ S, 136° 42’ E), Northern Territory, Australia.

W. Stalker collected the type specimen of P. mimulus in 1905 on Alexandria Station (Northern Territory). The species was subsequently named (then as Phascogale mimulus ) by British taxonomist O. Thomas in 1906 on the basis of a single female. Before 1967, P. mimulus was known only from the type specimen; Thomas distinguished P. mimulus (the single type) from P. macdonnellensis (two specimens, likely from Alice Springs) by the smaller size of the former and, most notably, by a dental difference. There are currently six recognized species of “false antechinuses:” bilarni , macdonnellensis , mimulus , ningbing , roryi , and woolleyae , macdonnellensis , and mimulus were initially placed in the genus Antechinus , along with Parantechinus apicalis . Nevertheless, with estimable foresight, G. H. H. Tate in 1947 erected a new genus, Pseudantechinus , for both macdonnellensis and mimulus , and a monotypic genus, Parantechinus , for apicalis . Unfortunately, W. D. L. Ride in 1964 doubted the validity of Tate’s new genera, returning all three species to Antechinus . Later, in 1982, P. A. Woolley examined penile morphology of Ride’s Antechinus supergroup and proposed that macdonnellensis , bilarni , the then undescribed “ ningbing ,” and apicalis formed a group distinct from other Antechinus . M. Archer in 1982 subsequently resurrected both of Tate’s genera, consigning macdonnellensis and “ ningbing ” to Pseudantechinus and bilarni and apicalis to Parantechinus . Genetic work on Pseudantechinus has paralleled morphological research since 1982 when P. R. Baverstock and colleagues used allozymes to confirm Tate’s Pseudantechinus and Parantechinus . Direct sequencing of mtDNA and nDNA has been conducted over the last decade indicating that the monotypic genera containing Parantechinus apicalis and Dasykaluta rosamondae are discrete from each other and the genus Pseudantechinus ; P. bilarni is clearly different genetically from Parantechinus ( P. apicalis ) and all other Pseudantechinus species; P. mimulus was recovered as sister to a clade containing P. macdonnellensis and P. rory: (notably, the latter two species were not reciprocally monophyletic). Interestingly, recent work has shown there to be a question about the taxonomy of P. mimulus in Queensland; some individuals from there do not have the same, purportedly diagnostic, features of the skull as described for the P. mimulus type specimen. Genetic and taxonomic revision is currently underway to clarify this confusion. Monotypic.

Distribution. Australia, Alexandria Station and the Sir Edward Pellew Group Is (Northern Territory) and several localities near Mt Isa (Queensland).

Descriptive notes. Head—body 8-9 cm (males) and 6:3.9-1 cm (females), tail 6.6-7 cm (males) and 5:6.7-6 cm (females); weight 14-18 g (males) and 14-25 g (females). Thereis slightly sexual dimorphism for size, but unlike most dasyurids, female Carpentarian Pseudantechinus appear to be slightly larger on average than males. Fur is buff brown above, with slight grayish tinge showing from base of hairs; belly is grayish-white, and there are rufous patches behind ears. Tail is tapering, usually swollen at base, and distinctly shorter than head-body length. Accessory erectile tissue of males forms an appendage to the penis. These characteristics distinguish the Carpentarian Pseudantechinus from all congeners except the Fat-tailed Pseudantechinus ( P. macdonnellensis ), compared to which the Carpentarian Pseudantechinus is typically smaller in size with a larger third upper premolar tooth.

Habitat. Sandstone outcrops and hills with surfaces of metamorphic or igneous rocks, sometimes open woodland. Carpentarian Pseudantechinuses on the Pellew Islands live on sandstone outcrops and hills with a pebbly/rocky surface; trees are scattered, containing mostly Eucalyptus tetrodonta ( Myrtaceae ), with a relatively dense shrubby understory; and hummock grass Plectrachne pungens ( Poaceae ) is also often present. In Queensland, most Carpentarian Pseudantechinuses occur in rocky areas, sometimes in open woodland habitat dominated by E. leucophloia, E. normantonensis, and Corymbia terminalis (all Myrtaceae ). At Pungalina-Seven Emu, they occur on fractured sandstone escarpments. In Queensland, they have been found among rocks and spinifex (7riodia, Poaceae ) in the vicinity of Rifle Creek Dam and on the side slope or base of sandstone ranges commonly featured in the Mount Isa landscape. This is further evidence that Carpentarian Pseudantechinuses are found not only on sandstone but also metamorphic or igneous rocky ranges. It remains to be seen if they are more widely distributed along rocky ranges in the Barkly Tablelands and Gulf hinterland, where few surveys have been undertaken to date.

Food and Feeding. The Carpentarian Pseudantechinus feeds voraciously on various insects; its tail can become fattened, being used as an energy reserve in lean times.

Breeding. A recent study of museum specimens suggested that the Carpentarian Pseudantechinusis a seasonal breeder. Based on examination of these specimens, mating most likely occurs in June-July, birth of young in August-September, and weaning of young in October-November. Female Carpentarian Pseudantechinuses are capable of breeding in at least two seasons, and males appearto survive beyond the mating period,as is the case for the Fat-tailed Pseudantechinus. Other studies found that none of seven female Carpentarian Pseudantechinuses caught on Pellew Island in July-August 1988 had pouch young, but four females captured in October 2003 had enlarged teats. Individuals trapped in November 1997 near MountIsa were scarcely weanedjuveniles.

Activity patterns. In captivity, the Carpentarian Pseudantechinus is nocturnal and moves with great agility among rocks. It hides by day among rocks and does not appear to build a nest.

Movements, Home range and Social organization. There is no information available for this species.

Status and Conservation. Classified as Endangered on The IUCN Red List. Listed as Vulnerable in Australia. The Carpentarian Pseudantechinus occurs in an area of less than 5000 km?, and all individuals are in fewer than five locations. There is continuing decline in habitat extent and quality and in number of mature individuals, probably due to changes in the fire regime and introduced predators. Mining is also a potential threat. Following its initial capture at Alexandria Station, there were no further records until J. Calaby collected three specimens in 1967 from North Island in the Sir Edward Pellew Group in the Gulf of Carpentaria. Additional collections made since 1988 have added Vanderlin, Centre and South Westislands (in the same group) to the known distribution of the Carpentarian Pseudantechinus. Its mainland distribution was extended in 1997 and 2002 with collections in the Mount Isa region. Carpentarian Pseudantechinuses have since been caught at a variety of locations in and around Mount Isa and Cloncurry in Queensland. In 2009-2010, four specimens were trapped and released, and others recorded via remote camera, on the Australian Wildlife Conservancy property of Pungalina-Seven Emu. A study conducted in 2011 found four additional records of Carpentarian Pseudantechinus from Queensland mountain ranges in the Mount Isa to Cloncurry region, including the Selwyn Range; the species may be more broadly distributed in Queensland than previously thought. The Pellew Islands in the Northern Territory are close to one another, as are the sites near Mount Isa and Cloncurry in Queensland, and taken together, these comprise less than five discrete sites, adding to their susceptibility to threat. The Carpentarian Pseudantechinus was first recorded from the Sir Edward Pellew Group in 1967 on North Island. In 1988, it was found again on North Island and Centre and South West islands. A survey in 2003 failed to find it on Centre and South West islands, but it was found again on North and Vanderlin islands. Carpentarian Pseudantechinuses are probably still present on all fourislands, although work is needed to confirm their continued existence on Centre and South West islands. Major conservation threats to Carpentarian Pseudantechinus are unknown; however, it is thought that changes to fire regime and destruction and degradation of habitat by introduced herbivores and livestock, predation by exotic predators, and plausibly disease contribute to its decline. Impacts of cane toads (Rhinella marina) and domestic and feral cats, which are present on all four islands from which the Carpentarian Pseudantechinus is known, is uncertain. The Carpentarian Pseudantechinus occurs in only one protected area: Barranyi (North Island) National Park, Northern Territory. A recovery plan was developed for 2004-2008; its recommendations include establishing a recovery team, communicating species information to stakeholders, targeting research to make informed decisions, minimizing impacts offeral cats, and improving fire management. During recent field surveys in the Mount Isa and Cloncurry region of Queensland, it was noted that buffelgrass ( Cenchrus ciliaris [= Pennisetum ciliare], Poaceae ) is in early stages of invasion on many rocky hill slopes suitable for Carpentarian Pseudantechinuses, including sites where they were trapped. The spread of this pasture grass is encouraged by graziers because replacement of native grasses, particularly spinifex (unpalatable to cattle) by buffelgrass improves livestock carrying capacity.

Bibliography. Archer (1982c), Baverstock et al. (1982), Cooper, N.K. et al. (2000), Johnson et al. (2008), Kitchener (1991), Kitchener & Caputi (1988), Krajewski & Westerman (2003), Lloyd et al. (2013), Ride (1964), Tate (1947), Taylor et al. (2004), Thomas (1888b, 1906), Westerman et al. (2007), Woinarski (2004a), Woinarski & Dickman (2008a), Woolley (1982, 2011).

Figures

On following pages: 29. Black-tailed Antechinus (Antechinus arktos); 30. Fawn Antechinus (Antechinus bellus); 31. Yellow-footed Antechinus (Antechinus flavipes), 32. Atherton Antechinus (Antechinus godmani); 33. Cinnamon Antechinus (Antechinus leo); 34. Swamp Antechinus (Antechinus minimus); 35. Buff-footed Antechinus (Antechinus mysticus); 36. Brown Antechinus (Antechinus stuartil); 37. Subtropical Antechinus (Antechinus subtropicus); 38. Dusky Antechinus (Antechinus swainsonii).

Distribution. Australia, Alexandria Station and the Sir Edward Pellew Group Is (Northern Territory) and several localities near Mt Isa (Queensland).