Topic
Strigocuscus
About: Strigocuscus is a research topic. Over the lifetime, 6 publications have been published within this topic receiving 85 citations.
Papers
TL;DR: Examination of the 12S rRNA gene of 2 elusive and morphologically plesiomorphic species of phalanger supports an evolutionary origin for the family approximately 34 million years ago, in the northwestern region of the Sahul Shelf, the continental mass underlying Australia and New Guinea.
Abstract: We sequenced the 12S rRNA gene of 2 elusive and morphologically plesiomorphic species of phalanger: the small Sulawesi cuscus (Strigocuscus celebensis—Gray, 1858) and the Sulawesi bear cuscus (Ailurops ursinus— Temminck, 1824). The sequences were integrated with previously existing data on the same gene in other species of phalangerids, as well as newly derived data from Wyulda Alexander, 1918. In contrast to current wisdom, we resolve S. celebensis not as a member of the tribe Trichosurini, but rather as a taxon sister to Ailurops in a reconstituted Ailuropinae in turn successively sister to Phalangerinae. Examination of our data supports an evolutionary origin for the family approximately 34 million years ago (mya), in the northwestern region of the Sahul Shelf, the continental mass underlying Australia and New Guinea. The radiation of the most plesiomorphic genera in the family, Trichosurus and Wyulda, is restricted to that region. S. celebensis, resolved as sister to A. ursinus in a clade ingroup to trichosurines, diverged from remaining ingroup lineages between 21.1 and 23.3 mya, a time when Sulawesi was available for colonization and sea currents would have enhanced the colonization potential from the east of Sulawesi and neighboring islands. We recommend Trichosurinae as a subfamilial level entity on par with Ailuropinae and Phalangerinae, circumscription of Trichosurinae to Trichosurus and Wyulda, and removal of Strigocuscus into Ailuropinae, leaving only Phalanger and Spilocuscus in Phalangerinae.
29 citations
TL;DR: It is concluded that the character states that link the ground cuscus with the Trichosurini are the result of convergence, and therefore the placement of several other species in the trichOSurin genus Strigocuscus based on the same characters should be reconsidered.
Abstract: A region of mitochondrial DNA, including the 3′ end of tRNA phenylalanine, the complete 12S rRNA and tRNA valine genes, and the 5′ end of 16S rRNA, was sequenced for four phalangerids and one burramyid; additional marsupial sequences were extracted from GenBank. Parsimony, minimum evolution, and maximum likelihood analyses show that the ground cuscus, Phalanger gymnotis, groups with the tribe Phalangerini, not with the tribe Trichosurini as had been suggested on the basis of certain morphological characters. This result is in agreement with an earlier study using DNA hybridization and is supported by some morphological evidence as well. We conclude that the character states that link the ground cuscus with the Trichosurini are the result of convergence, and therefore the placement of several other species in the trichosurin genus Strigocuscus based on the same characters should be reconsidered. The hypothesized close relationship of two fossil taxa, Strigocuscus reidi and S. notialis, to Phalanger gymnotis is also questionable because the fossils do not share morphological synapomorphies that link the ground cuscus to the Phalangerini.
15 citations
TL;DR: Comparisons with periotics of possums from the Tertiary Riversleigh deposits of Queensland suggest that, despite some similarities, the three extant trichosurins may be more closely related to each other than to the Riversleigh taxa.
Abstract: The morphology of the periotic in the extant trichosurin possums Strigocuscus celebensis and Wyulda squamicaudata is described and compared with that of various species of extant and extinct phalangerid marsupials. The periotic morphologies of S. celebensis and W. squamicaudata show a number of similarities with those of brushtailed possums of the genus Trichosurus, strengthening the case for a monophyletic tribe Trichosurini consisting of these three genera. Comparisons with periotics of possums from the Tertiary Riversleigh deposits of Queensland that were previously assigned on the basis of craniodental anatomy to Trichosurus and Strigocuscus suggest that, despite some similarities, the three extant trichosurins may be more closely related to each other than to the Riversleigh taxa. A revised morphological diagnosis of the Trichosurini is provided, incorporating these data.
13 citations
TL;DR: A single Early Miocene vicariant event between Australia and Papua New Guinea, which isolated phalangerines in the latter region, followed by dispersal of the included ailuropins to Sulawesi, would be sufficient to account for family-level cladogenesis in Phalangeridae.
Abstract: DNA-hybridisation experiments, involving seven species of Phalangeridae and two outgroup taxa in a complete 9 x 9 matrix, unequivocally placed the bear cuscus, Ailurops ursinus, nearest to the Phalangerini (Phalanger and Spilocuscus), with Trichosurini (Trichosurus) sister to both; and confirmed earlier molecular studies indicating that the ground cuscus, Strigocuscus gymnotis, is not a trichosurin but is closest to Phalanger. Our results thus conflict with the most thorough cladistic-anatomical study of phalangerids, which placed the bear cuscus outside all other Phalangeridae as the sole living member of Subfamily Ailuropinae; instead, we suggest that Ailurops should be considered representative of a tribe of Phalangerinae, Ailuropini, while Trichosurus (and presumably Wyulda, which was not examined here, as well as fossil Strigocuscus) would be removed from Phalangerinae and be considered a second subfamily of Phalangeridae, Trichosurinae, limited to Australia. Our estimate of the time of divergence of Ailurops and other phalangerines is about 16 myrbp; of Trichosurinae and Phalangerinae, about 21 myrbp. Thus, a single Early Miocene vicariant event between Australia and Papua New Guinea, which isolated phalangerines in the latter region, followed by dispersal of the included ailuropins to (or vicariant separation on) Sulawesi, would be sufficient to account for family-level cladogenesis in Phalangeridae.
12 citations
TL;DR: Strigocuscus notialis, a Pliocene species from Victoria is transferred to the new genus, Onirocuscus, based on phenetic similarity of its dentition to that of other species assigned to the genus.
Abstract: Crosby, K., March 2007. Rediagnosis of the fossil species assigned to Strigocuscus (Marsupialia, Phalangeridae), with description of a new genus and three new species. Alcheringa 31, 33-58. ISSN 0311-5518. The skull of the Miocene phalangerid Strigocuscus reidi is described for the first time. Anatomy of the new skull and the periotic of the holotype leads to a rediagnosis of the species and its placement in a new genus, Onirocuscus. Three new species are described from Riversleigh, Queensland, ranging from early to middle Miocene: O. silvacultrix, O. notialis, and O. rupina. Strigocuscus notialis, a Pliocene species from Victoria is also transferred to the new genus based on phenetic similarity of its dentition to that of other species assigned to the genus. Kirsten Crosby [k.crosby@three.com.au], School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, 2052, Australia; received 4.2.2005, revised 1.7.2005.
10 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2007 | 1 |
| 2006 | 1 |
| 2005 | 1 |
| 2003 | 1 |
| 2001 | 1 |
| 1999 | 1 |