Antechinus arktos, Dyck, 2014

Dyck, Steve Van, 2014, The Black-tailed Antechinus, Antechinus arktos sp. nov.: a new species of carnivorous marsupial from montane regions of the Tweed Volcano caldera, eastern Australia, Zootaxa 3765 (2), pp. 101-133 : 106-109

Antechinus arktos , sp. nov.

(Black-tailed Antechinus )

Etymology. The species epithet refers to the bear-like appearance of the holotype ( arktos is Greek for bear): very long guard hairs cover the body and the animal has a tendency to rear on its hind legs sniffing the air when disturbed, rather than the typical acrobatic leaping behaviour of most congeners. The common name refers to the evenly black-coloured tail of the species, especially when compared to the dark brownish tail of A. swainsonii .

Material. HOLOTYPE: QM JM 20009 (field number N86204), adult female, complete skull and dentary extracted. Body is deep frozen (destined for long-term storage as a puppet skin). DNA sample (liver) is stored in 95% ethanol and frozen. The specimen was collected on 28 May 2013 by A.M.Baker, T. Y. Mutton, H.B. Hines and J. Rowland in an Elliott trap baited with peanut butter, oats and bacon.

PARATYPE: The paratype specimen, QM JM20010 , was collected 28 May 2013 by A.M.Baker, T. Y. Mutton, H. Hines and J. Rowland from Bilbrough Lookout, Springbrook National Park , SEQ 28° 14´03˝ S 153° 17´23˝ E. This specimen was photographed live by Qld Museum photographer Gary Cranitch prior to accession into the Qld Museum collection (see Figure 4 ). Figure 5 shows features of the skull, dentary and teeth of the holotype specimen .

REFERRED SPECIMENS: ( JM prefixes are from the Queensland Museum; M prefixes are from the Australian Museum). These specimens were formalin-fixed and old so genetics was not possible. For the following adults skull morphology was used to confirm species identification as A. arktos : males JM834 O’Reilly’s Guest House , SEQ 28° 13´S 153° 07´E; JM835 Binna Burra Lodge , SEQ 28° 12´S 153° 11´E; JM836 Dave’s Creek Country Binna Burra , SEQ 28° 13´S 153° 13´E; JM2281 O’Reilly’s Guest House, SEQ 28° 14´S 153° 08´E (all preceding localities are within or immediately adjacent to Lamington NP) ; M20605 Eastern Border Ranges NP, NENSW 28° 23´S 153° 04´E , females: JM1595 Warrie NP (now within Springbrook NP) , SEQ 28° 13´S 153° 16´E; JM7949 Eastern Border Ranges NP, NENSW 28° 25´S 153° 07´E . In addition two juvenile specimens are assigned to A. arktos on the basis of external morphology: JM1594 National Park 752 (now within Springbrook NP) 28° 14´S 153° 16´E, SEQ and M20606 Eastern Border Ranges , NENSW 28° 22´S 153° 06´E .

Holotype locality. A small gully near Best of All Lookout , Mount Mumdjin, Springbrook National Park, south-east Queensland, Australia (28° 14´29.6˝ S 153° 15´50.6˝ E. Datum: GDA 94), 950m altitude.

Distribution. All specimens are from upland, high rainfall vegetation communities of the Tweed Shield Volcano caldera in south-east Queensland and north-east New South Wales. The species is currently only known from Springbrook NP, Lamington NP and Border Ranges NP (eastern section only). The following museum specimens from north-east New South Wales were registered as A. swainsonii but on re-examination by us were clearly not A. arktos or A. swainsonii : Australian Museum M31942 Grafton (reidentified as A. flavipes ); Australian Museum M29214 Conglomerate State Forest (reidentified as A. stuartii ); Australian Museum M12631 Coffs Harbour (reidentified as A. stuartii ); Australian National Wildlife Collection M24077 Tooloom (reidentified as A. stuartii ). There are published (e.g., Dickman, 1982) and unpublished records (e.g., Atlas of Living Australia, Atlas of NSW Wildlife) of A. swainsonii sensu lato between Ebor (type locality for A. s. mimetes) and the uplands of the Tweed caldera. However, without specimens and/or genetic samples we are unable to comment further on the identity of these records. Workers in this region are encouraged to retain voucher and tissue specimens to enable a better understanding of the distribution of A. arktos and A. s. mimetes.

Diagnosis. Summary of external differences amongst congeners. Antechinus arktos differs clearly from all other antechinus species, in having a combination of large-bodied, very shaggy and black-tailed appearance. A. arktos is more vibrantly coloured than A. swainsonii . A. s. mimetes is more uniformly deep brown-black to grizzled grey-brown from head to rump, with brownish (clove brown – raw umber) hair on the upper surface of the hindfoot and tail, whereas A. arktos is more colourful, having a marked change from greyish-brown head to orange-brown toned rump, fuscous black on the upper surface of the hindfoot and dense, short fur on the evenly black tail. Further, there is no distinct eye-ring but A. arktos has marked orange-brown fur on the upper and lower eyelid, cheek and in front of the ear and very long guard hairs all over the body, giving it a distinctively shaggy appearance; these characters, in specimens where they exist, are more subtle in A. swainsonii .

Summary of craniodental differences amongst congeners. A. arktos skulls are strikingly different to all subspecies of A. swainsonii . A. arktos are markedly larger than A. s. mimetes and A. s. swainsonii (Tasmania) for a range of craniodental measures, in particular: breadth across the snout, but with shorter anterior palatal vacuities and larger inter-palatal vacuity distance. Compared to all A. swainsonii subspecies, A. arktos skulls are most similar in size to A. s. insulanus from Grampians NP, Victoria. Nevertheless, there are a range of skull characters that differ between A. arktos and A. s. insulanus: A. arktos tend to have smaller upper second molar teeth but broader skulls, shorter anterior palatal vacuities and longer posterior palatal vacuities than A. s. insulanus.

Figures

FIGURE 4. (a–b) Photograph of live A. arktos paratype specimen; (c) underside hindfoot of the holotype specimen; note the dark pigmentation around the granules. Photographs (a–b) are Copyright Gary Cranitch (Qld Museum); photograph (c) is Copyright Harry Hines.

FIGURE 5. A. arktos holotype specimen photographs of skull and dentary (a–f): a. skull, top view; b. skull, bottom view; c. skull, side view; d. dentary, top view; e. dentary, bottom view; f. dentary, side view. Photographs are Copyright Andrew Baker.