Topic
Badjcinus
About: Badjcinus is a research topic. Over the lifetime, 4 publications have been published within this topic receiving 151 citations.
Papers
TL;DR: For some groups, notably Dasyuridae and a dasyurid clade inclusive of all modern subfamilies, the synapomorphic nature of some derived features appears to be robust, even where they also are present in some outgroup taxa.
Abstract: Dasyuromorphian relationships were investigated using cladistic analysis for 24 species using 77 cranial and dental features. Among the 7 extinct taxa used were 6 recently described fossil species, each well represented by cranial and dental material (3 ameridelphians, 1 peramelemorphian, and 2 dasyuromorphians). Monophyly for the Dasyuromorphia and several clades widely recognized therein is supported, but in many instances, relationships among extant dasyurids departs greatly from general consensus. Where congruence with previous investigations is evident, few taxa are united by unique synapomorphies within Marsupialia. Many clades are united by combinations of locally derived features only. Bootstrap and Bremer support is weak for most clades. Thus, although supported by cladistic analysis, the status of many synapomorphies identified in the course of this study are tentative. However, for some groups, notably Dasyuridae and a dasyurid clade inclusive of all modern subfamilies, the synapomorph...
52 citations
TL;DR: The breadth of thylacinid diversity evident during the middle Tertiary argues for an earlier origin for the family than that suggested by molecular-based investigations.
Abstract: Badjcinus turnbulli, gen. et sp. nov., is described from dental and incomplete skull material that includes the only pre-Pliocene dasyuromorphian basicranium described to date. Phylogenetic analysis places B. turnbulli basally within the Thylacinidae, but with autapomorphies. The relationship of B. turnbulli to other thylacines is assessed. The breadth of thylacinid diversity evident during the middle Tertiary argues for an earlier origin for the family than that suggested by molecular-based investigations. An amended diagnosis of the Thylacinidae is presented and thylacinid diversity and ecology is discussed.
48 citations
TL;DR: The phylogenetic relationships of dasyuromorphians are reassessed using a large molecular database comprising previously published and new sequences for both nuclear (nDNA) and mitochondrial (mtDNA) genes from the numbat, most living species of Dasyuridae, and the recently extinct marsupial wolf, to suggest that Thylacinidae is sister to Myrmecobiidae + Dasyurids.
TL;DR: Phylogenetic analysis supports the contention that, within the family, the dentition of N. dicksoni is unspecialised, less derived than the recent Thylacinus cynocephalus, and strengthens the argument that formal placement of D. murgonensis beyond the level of Marsupialia incertae sedisis unwarranted at present.
Abstract: The exceptionally well preserved skull and mandible of the Miocene thylacinid Nimbacinus dicksoni is described. Phylogenetic analysis supports the contention that, within the family, the dentition of N. dicksoni is unspecialised, less derived than the recent Thylacinus cynocephalus for at least 12 features. However, relatively few cranial specialisations evident in T. cynocephalus clearly distinguish it from N. dicksoni. These two taxa share at least three derived cranial features not present in the most generalised thylacinid known from significant cranial material, the late Oligocene Badjcinus turnbulli. On the other hand, where comparison is possible, even the most specialised thylacinid, T. cynocephalus, is plesiomorphic for at least 10 cranial features common to modern dasyurids and five present in the Miocene dasyurid, Barinya wangala. Two character states found in thylacinids are more derived than in B. wangala. Relative to the remaining dasyuromorphian family, Myrmecobiidae, represented by the monotypic Myrmecobius fasciatus, thylacinids are derived for five cranial features and plesiomorphic for five. It appears that despite considerable anatomical diversity among the dentitia of thylacinids and the presence of many highly specialised dental features in some species, the crania of thylacinids have remained remarkably conservative. Even with respect to dentitia, in terms of overall similarity, the Miocene Thylacinus macknessiand late Oligocene material referred to Thylacinus does not differ greatly from the recently extinct T. cynocephalus. It now also seems probable that T. macknessi was also very similar to T. cynocephalus with respect to cranial anatomy. Numerical parsimony analysis incorporating this new material produced moderate bootstrap and Bremer support for a monophyletic Thylacinidae. In this same treatment strict consensus placed Myrmecobius fasciatus as the sister taxon to Thylacinidae–Dasyuridae, but bootstrap and Bremer support was lacking. Both of these results are contra those of the most recent attempt to resolve dasyuromorphian relationships using numerical parsimony and anatomical data. In the present analysis, the early Eocene Australian taxon, Djarthia murgonensis, fell outside a clade inclusive of all other Australian taxa and was monophyletic with the borhyaeniod, Mayulestes ferox. This latter relationship is based on limited material, poorly supported and considered highly unlikely, but it does strengthen the argument that formal placement of D. murgonensis beyond the level of Marsupialia incertae sedisis unwarranted at present.
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2016 | 1 |
| 2001 | 1 |
| 2000 | 1 |
| 1998 | 1 |