Perameles nasuta Geoffroy, 1804

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 : 374-375

Perameles nasuta Geoffroy, 1804

Figs. 4–8

Perameles nasuta nasuta Geoffroy, 1804

Holotype. MNHP 327, Paris, mounted skin, type locality unknown (holotype not examined in this study).

Material examined. From the Queensland Museum: QM J4816, J4902, J4903, J4904, J4905, J4906, J5065, J5856, J7149, J8953, J9843, J10056 , J10057 , J10058 , J10730 , J11091 , J11210 , J11235 , J11236 , J22868 , JM410, JM651, JM790, JM5400, JM8757, JM9252, JM9757, JM10509, JM10719, JM11560, JM14370, JM14419, JM14584, JM15459, JM16435, JM19323, JM20175, JM20176, JM20177, JM20178, JM20248, JM20249, JM20250, JM20251, JM20252, JM20253, JM20254, JM20255, JM20256, JM20257,JM20258. From the Australian Museum: AM M4274, M6882, M8310, M8403, M14019, M21143, M24648, M25498.

Diagnosis. Perameles nasuta differs from P. pallescens in the following features: sagittal crest usually present in males; taller and wider posterolingual cusp and shelf on P3; StA smaller and does not ascend anterior flank of preparacrista on M1; StB taller than StC or fused with StC on M1; metaconule larger on M1–3, with postmetaconule crista ending further buccally; StA more buccally displaced on M3, resulting in more concave buccal margin of the tooth; StB present as medium to large sized conical cusp on M4; protocone larger on M4 with well-developed preprotocrista and postprotocrista; postparacrista usually connected to metacone on M4; a welldeveloped paracristid on m1; a larger talonid on m4.

P. na s u t a differs from P. gunnii in the following features: fewer bars in its pelage on its rump; less welldeveloped orbital rim; no ridges on the parietal; smaller lambdoidal sesamoid; smaller bullae; no accessory palatal or palatine fenestrae; smaller incisive and maxillopalatine fenestrae; shallower antorbital fossa; I4–5 not premolarlike; obvious sexual dimorphism in canines; main cusp of P3 less conical, and less well-developed lingual shelf; postmetaconule crista ends more buccally on all molars; StD connected to metaconule by a distinct crest on M1 (except in specimens from MEQ); minute anterior cingulum present on M2; trigonid of m4 much wider.

P. na s u t a 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; larger lingual cusp on P3 and better developed lingual shelf; postmetaconule crista ends more buccally on all molars; StD connected to metaconule by a distinct crest on M1 (except in specimens from MEQ); minute anterior cingulum present on M2.

P. na s u t a differs from P. sobbei in the following features: StA on M3 more anterobuccally positioned; metaconule on M3 better developed.

P. nasuta 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); metaconule better developed on M3.

P. nasuta differs from P. allinghamensis in having more developed metaconule and posterior cingulum; a much smaller anterior cingulum (when present); and a buccally displaced StA.

Remarks. Specimens from MEQ are unique amongst specimens of Perameles nasuta nasuta in having no connection between StD and the metastyle on M1. This feature is also seen in P. gunnii . This suggests that the MEQ population may be distinct and represent a separate subspecies, though it is not formally described as a separate taxon here, pending genetic analyses to support their separation.

Habitat. Heath and forest habitats close to grassy/open feeding sites, in rainfall over 750 millimetres, and elevation below 1000 metres ( Chambers & Dickman 2002; Van Dyck et al. 2013).

Distribution. From the Mackay region, to the south of Victoria along the east Coast of Australia.

Figures

FIGURE 4. Dorsal and ventral views of the skins of Perameles nasuta nasuta, represented by all specimens present in the Queensland Museum collections (A, B). 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.