Pucadelphys andinus (Marshall and de Muizon 1988; Marshall, de Muizon and Sigogneau-Russell 1995; Early Paleocene; 10cm snout-vent length) is an extinct marsupial basal to the sabertooth clade. It is known to be gregarious from a rare collection of twelve females, six males and five late stage juveniles. The tiny in situ fossil is shown life size above on a 72 dpi monitor.

Lycopsis longirostris (Cabrera 1927, Argot 2004; Middle Miocene, South America) nests with Pucadelphys in the LRT as a sprassodont marsupial.

Didelphodon vorax (Marsh 1889; Wilson et al. 2016; Late Cretaceous 80mya; 12 cm skull length) was a predator with blade-like cutting teeth and bulb-like crushing teeth. It had a long neck and short limbs. With such traits Didelphodon could have been an otter-like mollusc shell crusher. Wilson et al. tested only Cretaceous and Palaeogene taxa. They used many dental trait and nested Didelphodon closest to Borhyaena among tested taxa. Here Didelphodon nests in the Hadrocodium clade.

Didymoconus berkeyi (Matthew WD and Granger W 1924. Gingerich 1981, Wang X et al 2001; IVPP V11983, Eocene 52mya) is a former enigma taxon here nesting with Didelphodon. The zygomatic arches are wide posteriorly and the orbits are dorsally open in this slightly younger taxon taxon.

Mayulestes feox (Muizon 1994; 64 mya; MNHC P 1249; scale bar = 5cm) is a Palaeocene marsupial basal to Didelophodon. It was originally considered a borhyaenoid. Here it nests within the tiny flat-head marsupial clade close to Hadrocodium.

Asiatherium reshetovi (Trofimov and Szalay 1994, Szalay and Trofimov 1996; PIN 3907; Late Cretaceous; 80mya) is a key Mongolian metathere close to Mayulestes, but smaller. Note the flat skull and dorsal orbits. One specimen from a nesting site is shown in situ below.

Ameghino F 1892. (Issued in 1894.) Enumeration synoptique deses pesces de mammiferes fossilesdes formation sócénes de Patagonie. Boletindela, Academia Nacionalde Cienciasen Cordoba, XIII, p.259 (p.108 in reprint).

Argot C 2004. Functional-adaptive analysis of the postcranial skeleton of a Laventan Borhyaenoid, Lycopsis longirostris (Marsupialia, Mammalia). Journal of Vertebrate Paleontology 24(3):689–708.

Cabrera A 1927. Datos para el conocimiento de los Dasiuroideos fósiles argentinos. Revista del Museo de La Plata 30:271–315.

Cope ED 1875. On the Supposed Carnivora of the Eocene of the Rocky Mountains. Proceedings of the Academy of Natural Sciences, Philadelphia. pp. 444–449.

Gingerich PD 1981. Radiation of Early Cenozoic Didymoconidae (Condylarthra, Mesonychia) in Asia, with a New Genus from the Early Eocene of Western North America. Journal of Mammalogy 62(3):526-538.

Gregory WK and Simpson GG 1926. Cretaceous mammal skulls from Mongolia. American Museum Novitates 225, 7-20.

Marsh OC 1889. Discovery of Cretaceous Mammalia, part i, ii. American Journal of Science, Series 3 38: 81–92; 177–180.

Marshall LG and Muizon C de 1988. The dawn of the age of mammals in South America. National Geographic Research 4 (1): 23-55.

Marshall LG, de Muizon C and Sigogneau-Russsell D 1995. Pucadelphys andinus (Marsupialia, Mammalia) from the early Paleocene of Bolivia. Part I: The locality of Tiupampa: age, taphonomy and mammal fauna. Mémoires du Muséum national d'histoire naturelle 165: 11–20.

Matthew WD and Granger W 1924. New Carnivora from the Tertiary of Mongolia. American Museum Novitates (104).

de Muizon C 1994. A new carnivorous marsupial form the Palaeocene of Bolivia and the problem of marsupial monophyly. Nature 370:208–211.

Pine RH, Flores DA and Bauer K 2013. The second known specimen of Monodelphs unistriata (Wagner) (Mammalia: Didelphimorphia), with redescription of the species and phylogenetic analysis. Zootaxa3640 (3):425-441.

Trofimov BA and Szalay FS 1994. New Cretaceous marsupial from Mongolia and the early radiation of Metatheria. Proceedings of the National Academy of Sciences 91:12569-12573

Wilson GP, Eddale EG, Hoganson JW, Calede JJ and Vander Linden A 2016. A large carnivorous mammal from the Late Cretaceous and the North American origin of marsupials. Nature Communications 7:13734 PDF

wiki/Monodelphis.sorex
wiki/Didelphodon
wiki/Asiatheriium
wiki/Mayulestes
wiki/Pucadelphys
wiki/Lycopsis