Antechinus bellus (Thomas, 1904)

Dyck, Steve Van, 2013, Taxonomy and redescription of the Fawn Antechinus, Antechinus bellus (Thomas) (Marsupialia: Dasyuridae), Zootaxa 3613 (3), pp. 201-228 : 215

(7) A. bellus versus A. swainsonii

Pelage: Antechinus bellus is a strikingly pale animal: pale to medium grey above, sometimes with a faun tinge, whereas A. swainsonii is grizzled grey-brown from head to rump.

External measurements: Antechinus bellus is larger than A. swainsonii in absolute measurement (i.e., with no overlap in ranges) for the following external characters in males: ear length, and no characters in females. A. bellus is significantly larger than A. swainsonii for males in tail length, larger for females in ear length and smaller for females in body weight (Table 2).

Skull: Antechinus bellus differs from A. swainsonii in absolute measurement (i.e., with no overlap in ranges) for the following 13 skull/dentary characters for males: APV, IBW, IOW, IPV, M 2 W, R-LC 1, R-LM 1, R-LM 2, R- LM 3, SWR-LC 1 B, BuL, I 1 -P 3 and UPL and the following 17 skull/dentary characters for females: APV, IBW, IOW, IPV, M 2 W, PPV, R-LC 1, R-LM 1, R-LM 2, R-LM 3, SWR-LC 1 B, HT-B, BuL, I 1 -P 3, I 1 -P 3, M 2 W and UPL. Moreover, A. bellus has a range of other dentary features that significantly (p<0.01) differ from A. swainsonii — 8 variables for males and 8 variables for females, as shown in Table 2.

Other comments: Antechinus bellus is found in savannah woodlands of the Top End, Northern Territory, whereas A. swainsonii is found in south-eastern Australia from Tasmania in the south to far south-east Qld in the north. A. bellus females have 10 nipples in the pouch, whereas A. swainsonii females have 6–10 nipples in the pouch. A. bellus possesses a distally thickened and twisted supratragus of the ear rather than the simple, uncurled structure found in A. swainsonii . Genetics: uncorrected pairwise difference at the mitochondrial gene Cytochrome B (CytB) between A. bellus and A. swainsonii is 15.7%.