Perameles pallescens Thomas, 1923

Travouillon, Kenny J., 2016, Investigating dental variation in Perameles nasuta Geoffroy, 1804, with morphological evidence to raise P. nasuta pallescens Thomas, 1923 to species rank, Zootaxa 4114 (4), pp. 351-392 : 375-376

Perameles pallescens Thomas, 1923 stat. nov.

Figs. 3 , 5–8

Perameles nasuta pallescens Thomas, 1923: 173

Holotype. BMNH 22.12.18.40, preserved skin and skeleton of adult male from Vine Creek, Ravenshoe, Queensland, Australia.

Topotype. QM JM18575, preserved skin and skeleton of adult male from Mt Father Clancy, Ravenshoe, Queensland, Australia.

Other material examined. From the Museum of Natural History, London: BMNH 22.12.18.41. From the Australian Museum: AM M15841. From the Queensland Museum: QM J6350, J9421, J10816 , J14308 , JM6561, JM6683, JM11389, JM18575, JM20172, JM20173, JM20174, JM20239, JM20240, JM20241, JM20242, JM20243, JM20244, JM20245, JM20246, JM20247.

Diagnosis. Perameles pallescens differs from P. nasuta in having the following features: sagittal crest either very small or absent in males; smaller and narrower posterolingual cusp and shelf on P3; StA larger and bladed, ascending the anterior flank of preparacrista on M1; StB shorter than StC on M1; metaconule smaller on M1–3, with postmetaconule crista ending more lingually; StA more lingually positioned on M3, resulting in a less concave buccal margin of the tooth; StB either absent or present as small conical cusp on M4; protocone smaller on M4 with poorly developed preprotocrista and postprotocrista; postparacrista not connected to metacone on M4; a poorly developed paracristid on m1, not connected to the protoconid; a smaller talonid on m4.

P. pallescens differs from P. gunnii in having the following features: fewer bars in its pelage on its rump; less well-developed orbital rim; no ridges on the parietal; smaller lambdoidal sesamoid; smaller bullae; no accessory palatal fenestrae; smaller incisive and maxillopalatine fenestrae; shallower antorbital fossa; I4–5 not premolar-like; obvious sexual dimorphism in canines; main cusp of P3 less conical, and less well-developed lingual shelf; metaconule less well-developed on M3; StA larger and bladed, ascending the anterior flank of preparacrista on M1; StD connected to metaconule by a distinct crest on M1; minute anterior cingulum present on M2; less welldeveloped StB and protocone on M4; a poorly developed paracristid on m1, not connected to the protoconid; trigonid of m4 much wider.

P. pallescens differs from P. bougainville in the following features: larger in overall size; fewer bars in its pelage on its rump; no accessory palatal or palatine fenestrae; smaller maxillopalatine fenestrae; taller postglenoid process; shallower antorbital fossa; lingual cusp and lingual shelf on P3 slightly larger in size; StA larger and bladed, ascending the anterior flank of preparacrista on M1; StD connected to metaconule by a distinct crest on M1; minute anterior cingulum present on M2; a poorly developed paracristid on m1, not connected to the protoconid.

P. pallescens differs from P. sobbei having a poorly developed paracristid on m1, not connected to the protoconid.

P. pallescens differs from P. bowensis in the following features: all dental dimensions larger; main cusp of P3 less conical and narrower; anterior cingulum on M2 much smaller; anterior cingulum on M3 much smaller (if present); a poorly developed paracristid on m1, not connected to the protoconid.

P. pallescens differs from P. allinghamensis in a much smaller anterior cingulum (when present); and a buccally displaced StA.

Remarks. A new topotype is established here, to facilitate research and specimen identification in Australia (from a Queensland Museum specimen), considering that the holotype is located in the British Museum of Natural History in London, UK.

Habitat. Rainforest, wet sclerophyll forests, woodlands, swamps and farmlands ( Harrison 1962; Gordon et al. 1990; Williams & Marsh 1998; Bateman 2010; Kanowski et al. 2010a, b)

Distribution. From the Townsville region to Cape York Peninsula, on the east coast of Queensland, Australia.

Figures

FIGURE 3. Dorsal and ventral views of the skins of Perameles nasuta pallescens, represented by the holotype (A, B; adult male; BMNH 22.12.18.40) and all other specimens present in the Queensland Museum collections (C, D). Arrow points to bar pattern in the pelage. Scale bar = 10 cm.

FIGURE 5. Lateral views of the skins of Perameles nasuta pallescens (A, topotype, QM JM 18575), P. n. nasuta (B, QM J 11236), P. gunnii (C, QM JM 16110) and P. bougainville (D, QM J 11207). Arrow points to bar pattern in the pelage. Scale bar = 10 cm.

FIGURE 6. Lateral, dorsal and ventral views of the skull and dentary of Perameles nasuta pallescens (A – C, holotype, BMNH 22.12. 18.40, male; D – F, topotype, mirrored, QM JM 18575, male) and P. n. nasuta (G – I, QM JM 20178, female). Arrow points to accessory cusp on canine. Scale bar = 10 mm.

FIGURE 7. Occlusal and lingual views of the upper third premolar and molars of Perameles nasuta pallescens (A – B, topotype, QM JM 18575) and P. n. nasuta (C – D, QM JM 20178; E – F, mirrored image, QM J 4906). Arrows point to morphological differences mentioned in the text. Scale bar = 3 mm.

FIGURE 8. Occlusal and buccal views of the lower third premolar and molars of Perameles nasuta pallescens (A – B, topotype, QM JM 18575; G, magnesium oxide coated m 1, J 6350) and P. n. nasuta (C – D, mirrored image, QM JM 20178; E – F, QM J 4906; H, magnesium oxide coated m 1, QM J 4906). Arrows point to morphological differences mentioned in the text. Scale bar = 3 mm.