The Black-tailed Antechinus, Antechinus arktos sp. nov.: a new species of carnivorous marsupial from montane regions of the Tweed Volcano caldera, eastern Australia Author Dyck, Steve Van Queensland Museum, Vertebrate Zoology (Mammals & Birds), PO Box 3300, South Brisbane, Qld, 4101, Australia text Zootaxa 2014 2014-02-17 3765 2 101 133 journal article 5910 10.11646/zootaxa.3765.2.1 300ad198-2377-4bfd-9381-6868ee9c5f7a 1175-5326 5045725 E7DDABDA-5DA6-4309-A26F-121FCB030EEE (6) A. arktos versus A. agilis Dickman, Parnaby, Crowther & King Pelage: A. arktos has a brownish-grey head that changes markedly to an orange-brown rump, fuscous black hindfeet, a thick-based, finely-furred, black tail and an orange-yellow eye and cheek patch; A. agilis is a uniform medium grey to greyish brown from head to rump. A. agilis also has a light-coloured ring of fur around the eyes. External Measurements: A. arktos is larger than A. agilis in absolute measurement for wt, hb, tv, hf in males and hf in females. A. arktos is significantly larger than A. agilis in wt for females ( Table 5 ). Craniodental Characters: A. arktos is larger than A. agilis in absolute measurement for a range of characters: for males APV, BL, Dent, IBW, IOW, M 2 W, NW, OBW, PPV, R-LM 1 , R-LM 1 T, ZW, HT, PL, TC, NWR, PML, UML, HT-B, BuL, I 1 -P 3 , LML, I 1 -P 3 , M 2 W and UPL; for females APV, BL, Dent, IBW, IOW, OBW, PPV, HT, PL, TC, NWR, PML, UML, HT-B, I 1 -P 3 , LML, I 1 -P 3 , M 2 W and UPL. A. arktos is significantly larger than A. agilis at R- LM 3 in males and NW in females ( Table 5 ). TABLE 5 ANOVA F-statistics (top two lines) for variation at each of the measured variables among all antechinus species and subspecies. Subsequent rows show significance values for ANOVA Post-Hoc tests of Antechinus arktos paired with each of its 12 congeners, for each measured variable. Shaded cells are significant at p=0.05, unshaded cells are not significant. Other Comments: A. arktos occur in south-east Qld and north-east NSW in areas of high elevation and rainfall on the Tweed Volcano caldera, whereas A. agilis is known only from south-eastern Australia , south of around Sydney’s (NSW) latitude. Genetics: Uncorrected pairwise range differences at the mitochondrial gene CytB between A. arktos and A. agilis are 15.1–15.9%.