Petaurus breviceps (Waterhouse, 1838)

Cremona, Teigan, Baker, Andrew M., Cooper, Steven J. B., Montague-Drake, Rebecca, Stobo-Wilson, Alyson M. & Carthew, Susan M., 2021, Integrative taxonomic investigation of Petaurus breviceps (Marsupialia: Petauridae) reveals three distinct species, Zoological Journal of the Linnean Society 191, pp. 503-527 : 516-518

PETAURUS BREVICEPS (WATERHOUSE, 1838)

Recommended common name: Sugar glider.

Etymology: The species name breviceps derives from the Latin words brevis, short, and the suffix - ceps, headed.

Type specimen: Holotype NHMUK 1855.12 .24.78, adult female skin (no skull located). The type skin is depicted in Figure 13.

Type locality: Jackson & Thorington (2012) lists the type locality as Sydney, NSW. However, we have been unable to locate any more specific locality information. The tag with the type specimens lists New South Wales and the texts of Waterhouse to accompany the specimen do not provide any evidence of a more specific type locality .

Distribution: Based on genetic and morphological evidence, the species distribution extends from the Victorian border in the south to north of Brisbane. The species occurs on the eastern or coastal side of the Great Dividing Range. Further research is needed to determine the extent of the distribution in southern coastal Queensland.

Diagnosis: Due to its more restricted, coastal distribution ( Fig. 3), P. breviceps is the least variable of the small Petaurus spp. (Stobo-Wilson et al., in press). Petaurus breviceps has a less clearly defined and often narrow dorsal stripe when compared to P. ariel and to a lesser extent P. notatus . The stripe fades at a point before the hindlegs. The tail of P. breviceps is less attenuated than that of P. notatus .

The intraorbital width of P. breviceps skulls is significantly smaller than that of P. notatus , while the nasal width of P. breviceps is larger. There is a tendency for P. breviceps skulls to have a smaller zygomatic width. This is only significant in females, but may be attributable to a smaller sample size in males ( Tables 2, 3). The skulls of P. breviceps and P. notatus were similar for all other measurements.

A geographic barrier appears to exist between P.breviceps and P. notatus , but given the close proximity of samples in the current study, it is possible that the species also co-occur. Petaurus breviceps co-occurs with P. norfolcensis but is distinguished by its significantly smaller size and blunt nose.

DESCRIPTION OF HOLOTYPE 1855.12.24.78 OF PETAURUS BREVICEPS

Specimen is poorly preserved. Fixed position of the specimen makes detailed description difficult. Observations were taken where possible.

External measurements: Hindfoot length: 24 mm; hand: 18 mm; head–body length: 155 mm; tail– vent length: 107 mm (partial, as tail damaged and incomplete); ear length: 14 mm (one missing).

Pelage: Colours of the Petaurus breviceps holotype are as follows. Dorsal body coloration varies from mouse grey to hairbrown. A bone-brown, mid-dorsal stripe commencing at a point posterior between the anterior edge of the eyes is only distinguishable over the ear and stops 13 mm posterior to the ears. The stripe is 4 mm wide between the ears. An indistinct stripe is visible as a slight darkening over the mid-back of the specimen, but it is not defined.

Fur of the mid-back is 10–12 mm long with colour varying over its length. The basal 7 mm is mouse grey, median 4 mm is olive brown and apical 1 mm tipped deep olive buff.

The head is furred mouse grey and a thin ring of fuscous-black encircles the eye as an eye ring. An indistinct mummy-brown ring forms an incomplete circle around the ear with a distinct thickening at the base of the ear. A patch of smoke grey fur on the posterior edge of the pinna forms a less conspicuous tuft, interrupting the ear ring. The gliding membrane is concealed by positioning of the specimen.

The soft ventral fur (12 mm long on the belly) is olive buff tending to drab, giving the ventral fur a dusty wash.

A thin covering of fuscous hairs is present on the dorsal surface of the forefeet digits, contrasting with a ‘mitten’ of mummy-brown fur extending to the shoulder and a strong forearm stripe. Hindfeet are slightly more thickly covered fuscous, which gently contrasts with a less distinct ‘mitten’ of olive brown over the metatarsals, extending up to the inner posterior region of the thigh in a triangular stripe almost to the top of the thigh.

The tail is furred sepia and is incomplete/broken in the specimen. The tail tip is absent.

Fur 20 mm from the base of the tail is 19 mm long.

Vibrissae: Approximately 12 black mystacial vibrissae occur on each side and these are up to 28 mm long. Supra-orbital vibrissae (2); genals (2).

Pes and manus: The claws of the fore and hindfeet are relatively large with maximum chord length of digit 4 claws approx. 12 mm. Digit 4 is the longest digit of manus or pes, and digit 4> 5> 3> 2> 1.