Extant Dactylopsila and two Late Cretaceous descendants

The extant striped opossum,
Dactylopsila (Figs 1, 2) now has three extinct relatives / descendants in the large reptile tree (2320 taxa). Two are from the Late Cretaceous. One is from the Eocene.

Figure 1. The extant striped opossum Dactylopsila in vivo. ” data-image-caption=”

Figure 1. The extant striped opossum Dactylopsila in vivo.

” data-medium-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/07/dactylopsila_trivirgata588invivo.jpg?w=279″ data-large-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/07/dactylopsila_trivirgata588invivo.jpg?w=584″ tabindex=”0″ role=”button” class=”size-full wp-image-87375″ src=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/07/dactylopsila_trivirgata588invivo.jpg” alt=”Figure 1. The extant striped opossum Dactylopsila in vivo.” width=”584″ height=”628″ />

Figure 1. The extant striped opossum Dactylopsila in vivo.

Dactylopsila trivirgata 
(Gray 1858, Figs 1, 2) is the extant striped possum, an arboreal marsupial the size and proportions of a placental squirrel, but with a prehensile tail. The fourth finger is elongated and used to extract beetles and caterpillars from tree bark. This omnivore also eats leaves, fruit and small vertebrates.

The three extinct relatives in the LRT include
Adalatherium, Vintana and Groeberia (Fig 2).

Figure 2. Dactylopsila to scale with three relatives, all extinct: Adalatherium, Vintana and Groeberia. ” data-image-caption=”

Figure 2. Dactylopsila to scale with three relatives, all extinct: Adalatherium, Vintana and Groeberia.

” data-medium-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/07/vintana-dactylopsila-adalatherium-groeberia2scale588.jpg?w=121″ data-large-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/07/vintana-dactylopsila-adalatherium-groeberia2scale588.jpg?w=414″ tabindex=”0″ role=”button” class=”size-full wp-image-87378″ src=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/07/vintana-dactylopsila-adalatherium-groeberia2scale588.jpg” alt=”Figure 2. Dactylopsila to scale with three relatives, all extinct: Adalatherium, Vintana and Groeberia. ” width=”584″ height=”1445″ />

Figure 2. Dactylopsila to scale with three relatives, all extinct: Adalatherium, Vintana and Groeberia. Little Groeberia enlarged below.

Adalatherium hui
(Krause et al. 2020; Late Cretaceous) was originally considered a relative of multituberculates, but here nests with Dactylopsila, an extant striped opossum with similarly large incisors.

Vintana sertichi
(Krause et al. 2014; Late Cretaceous, UA 9972; 12.4 cm skull length; is a Madagascar mammal originally considered a member of the Allotheria and Gondwanatheria, two clades that are not recovered in the large reptile tree. The LRT nests Vintana with Groeberia and Dactylopsila (Fig 2)

Krause et al reported, “The new taxon is the largest known mammaliaform from the Mesozoic of Gondwana. Its craniofacial anatomy reveals that it was herbivorous, large-eyed and agile, with well-developed high-frequency hearing and a keen sense of smell. The cranium exhibits a mosaic of primitive and derived features, the disparity of which is extreme and probably reflective of a long evolutionary history in geographic isolation.”

Groeberia minoprioi
(Patterson 1952,  MMP 738) Groeberia pattersoni (Simpson 1970; Eocene and Oligocene). Simpson & Wyss 1999, considered it close to diprotodontians (wombats). The LRT supports that nesting as Groeberia nests with Vintana, another former enigma, both within the marsupials.

This bit of housekeeping
modified the earlier hypothesis of interrelationships.

References
Burmeister CV 1888. Relaciónde un viaje a la Gobernaciónde Chubut. Anales del Museo Nacional de Buenos Aires 3:175–252,
Cerdeño E and Bond M 1998. Taxonomic Revision and Phylogeny of Paedotherium and Tremacyllus (Pachyrukhinae, Hegetotheriidae, Notoungulata) from the Late Miocene to the Pleistocene of Argentina. Journal of Vertebrate Paleontology 18(4): 799-811.
Chimento NR, Agnolin  FL and Novas FE 2015. The bizarre ‘metatherians’ Groeberia and Patagonia, late surviving members of gondwanatherian mammals. Historical Biology: An International Journal of Paleobiology. 27 (5): 603–623.
doi:10.1080/08912963.2014.903945
Gray JE 1858. List of species of Mammalia sent from the Aru Islands by Mr A.R. Wallace to the British Museum. Proceedings of the Zoological Society of London. 26: 106–113. Krause DW, Hoffmann S, Wible JR, Kirk EC, and several other authors 2014. First cranial remains of a gondwanatherian mammal reveal remarkable mosaicism. Nature. online. doi:10.1038/nature13922. ISSN 1476-4687.
Krause DW et al. 2014. Vintana sertichi (Mammalia, Gondwanatheria) from the Late Cretaceous of Madagascar. Journal of Vertebrate Paleontology Memoir 14. 222pp.
McKenna MC 1980. Early history and biogeography of South America’s extinct land mammals.
Patterson B 1952. Un nuevo y extraordinario marsupial deseadiano. Rev Mus Mun Cienc NatMar del Plata. 1:39–44.
Simpson GG 1970. Addition to the knowledge of Groeberia (Mammalia, Marsupialia) from the mid-Cenozoic of Argentina. Breviora 362:1-17

wiki/Vintana
wiki/Groeberia
wiki/Adalatherium
wiki/Striped_possum – Dactylopsila trivirgata