Megaconus and Daubentonia

Daubentonia madagascariensis (Gmelin 1788, originally Sciurus madagascariensis; Geoffrey Saint-Hilaire 1795; 40 cm snout-to-vent length) is the extant aye-aye. Originally it was considered a squirrel, then traditionally an odd sort of lemur-like primate with rodent-like teeth. Here Daubentonia returns to Glires with Megaconus a basal member of Multituberculata. This nocturnal arboreal mammal has a long slender digits, particularly manual digit 3, which is used to probe for insects below tree bark. Note the hallux-like pedal digit 1.

Megaconus skull in situ and reconstructed

Megaconus mammaliaformis (Zhou et al. 2013, Middle Jurassic) is a member of the Haramiyida, traditionally considered pre-mammals. Here Megaconus nests with multituberculates and Daubentonia. A deep coat of fur was preserved with this complete fossil. Zhou et al. reported the posterior mandible bones were not yet transformed into tiny ear bones. Actually this represents a reversal due to that sliding jaw joint, based on the rest of the traits.

Gmelin JF 1788. Caroli a Linné systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima tertia, aucta, reformata. - pp. [1-12], 1-500. Lipsiae. (Beer).

Geoffroy Saint-Hilaire E 1795. La décade philosophique, litteraire, et politique. Memoires d’Histoire Naturelle 4(28):193– 206.

Owen R 1863. Monograph on the Aye-Aye (Chiromys madagascariensis, Cuvier)

Picone B and Sineo L 2012. The phylogenetic position of Daubentonia madagascariensis (Gmelin, 1788; primates, Strepsirhini) as revealed by chromosomal analysis. Caryologia: International Journal of Cytology, Cytosystematics and Cytogenetics 65(3):223-228. online here.

Sterling E. 1994. Taxonomy and distribution of Daubentonia: a historical perspective.Folia Primatologica 62:8-13.

Zhou CF, Wu S, Martin T, Luo ZX 2013. A Jurassic mammaliaform and the earliest mammalian evolutionary adaptations. Nature 500 (7461): 163. doi:10.1038/nature12429.

wiki/Megaconus
wiki/Aye-aye - Daubentonia

Mammalia - Monotremata

Ornithorhynchus and kin

Marsupiala - Metatheria

Eomaia and kin

Monodelphis and kin

Placentalia 2

Scandentia

Asioryctes

Ptilocercus

Tupaia

Trogosus