A Systematic Analysis of the Brushtail Possum, Trichosurus-Vulpecula (Kerr, 1792) (Marsupialia, Phalangeridae)

1991 ◽  
Vol 39 (3) ◽  
pp. 313 ◽  
Author(s):  
JA Kerle ◽  
GM Mckay ◽  
GB Sharman

The taxonomic status of distinctive populations of the widespread and morphologically variable possum Trichosurus vulpecula was examined. For the analysis, morphological characters (body size, fur colour and skull dimensions), karyotypes, electrophoretic allozyme, and ecological data were compared for as many Trichosurus populations as possible. There are insufficient differences between populations of T. vulpecula to reject a null hypothesis that they comprise a single species. Tasmanian, northern and south-western Australian populations could be retained as subspecies, but insufficient data exist to resolve the specific status of Atheton Tabeland and north-eastern Australian populations. One enigmatic result is that the skull morphometrics and allozymes of T. caninus were not distinguishable from those of sympatric T. vulpecula. However, other morphological characteristics and ecological data provide adequate evidence the T. caninus is a distinct species.

2019 ◽  
Author(s):  
Kunal Arekar ◽  
S. Sathyakumar ◽  
K. Praveen Karanth

AbstractTaxonomy is replete with groups where the species identity and classification remain unresolved. One such group is the widely distributed Hanuman langur (Colobinae: Semnopithecus). For most part of the last century, Hanuman langur was considered to be a single species with multiple subspecies. Nevertheless, recent studies using an integrative taxonomy approach suggested that this taxon is a complex, with at least three species. However, these studies did not include the Himalayan population of the Hanuman langur whose taxonomic status remains unresolved. The Himalayan population of Hanuman langurs have been classified as a distinct species with multiple subspecies or have been subsumed into other species. These classification schemes are wholly based on morphological characters and which are sometimes insufficient to delimit different species. Here, we have integrated data from multiple sources viz. morphology, DNA, and ecology to resolve the taxonomy of the Himalayan langur and to understand its distribution limit. Our results with three lines of evidence corresponding to three different species concepts show that Himalayan langur is a distinct species from S. entellus of the plains. Additionally, these results did not show any support for splitting of the Himalayan langur into multiple subspecies. Our study supports the classification proposed by Hill (1939) and we recommend Semnopithecus schistaceus, Hodgson 1840 as species name for the Himalayan langur and subsume all the known subspecies into it.


Author(s):  
Udon Pongkawong ◽  
◽  
Jatupol Kampuansai ◽  
Rossarin Pollawatn ◽  
Arunothai Jampeetong ◽  
...  

Abstract “Dok Hin” is the Thai local name for Selaginella species that form rosettes. They commonly distributes in Siberia, Manchuria, southern China, Japan, the Philippines and Thailand. Morphology of Dok Hin is very resemble leading to misidentification. So, exactly number of species of Dok Hin in Thailand and their differences in morphological characteristics is not well understood. Thus, revision of morphological characters and phylogenetic confirmation of the taxonomic identification are needed. This study aims to examine morphological charateristics and phylogenetic patterns in eight populations of the Dok Hin in Northern Thailand. Morphology of Dok Hin from each populations was quantitatively examined using 15 vegetative and 6 reproductive characters meanwhile phylogenetic analyses was explored by DNA barcode ITS2. The results of the phylogenetic analysis revealed the existence of two species of Dok Hin, S. tamariscina and S. pulvinata. Selaginella tamariscina can be distinguished from S. pulvinata by its presence of a pseudotrunk above ground and ridges of dorsal leaves. On the other hand, the results of phylogenetic analysis indicated the differences among populations of S. pulvinata as well. Chiang Mai populations of S. pulvinata was characterized by peculiar set of characters long leaves and leaf apices look like caudate, while the rest of their populations have shorter leaves and leaf apices look like aristate. It indicates that S. pulvinata has genetic and phenotypic divergence among populations. However, additional studies of Dok Hin populations in other parts of Thailand and studies on different genetic markers are necessary to confirm the taxonomic status of S. pulvinata. Keywords: Dok Hin, Morphometric, Phylogeny, Pseudotrunk, Resurrection plant


2004 ◽  
Vol 118 (3) ◽  
pp. 326 ◽  
Author(s):  
Caroline Healy ◽  
Lynn J. Gillespie

The Saxifraga nivalis complex displays significant ecological, morphological and cytological variation. Most European studies suggest that the S. nivalis complex comprises two distinct species: Saxifraga nivalis sensu stricto and Saxifraga tenuis. However, the presence of intermediate morphotypes, inconsistencies in chromosomal counts and variability in morphological keys and descriptions have led to different taxonomic interpretations of the complex in North America. This study investigated the systematics of Canadian Arctic Island members of this complex from 157 specimens using 23 morphological characters. Principal component analysis of the morphological data revealed two adjacent clusters, corresponding to the two taxa and consistent with a close morphological similarity and the presence of hybrids. A preliminary restriction site analysis of five non-coding regions of the chloroplast genome, trnH-trnK, trnT-trnF, trnF-trnV, trnV-rbcL and rbcL-ORF106, was conducted using 21 restriction endonucleases. This analysis indicated a length difference between the trnT-trnF region of S. nivalis and that of S. tenuis, but no difference in restriction sites for any of the assayed regions. These results confirm that in the Canadian Arctic, the S. nivalis complex consists of two closely related, largely sympatric species, with notable morphological variability, and possible hybrids.


Parasitology ◽  
2008 ◽  
Vol 136 (2) ◽  
pp. 241-252 ◽  
Author(s):  
T. L. F. LEUNG ◽  
D. B. KEENEY ◽  
R. POULIN

SUMMARYRecent studies have shown that some digenean trematodes previously identified as single species due to the lack of distinguishing morphological characteristics actually consist of a number of genetically distinct cryptic species. We obtained mitochondrial 16S and nuclear ITS1 sequences for the redial stages of Acanthoparyphium sp. and Curtuteria australis collected from snails and whelks at various locations around Otago Peninsula, New Zealand. These two echinostomes are well-known host manipulators whose impact extends to the entire intertidal community. Using phylogenetic analyses, we found that Acanthoparyphium sp. is actually composed of at least 4 genetically distinct species, and that a cryptic species of Curtuteria occurs in addition to C. australis. Molecular data obtained for metacercariae dissected from cockle second intermediate hosts matched sequences obtained for Acanthoparyphium sp. A and C. australis rediae, respectively, but no other species. The various cryptic species of both Acanthoparyphium and Curtuteria also showed an extremely localized pattern of distribution: some species were either absent or very rare in Otago Harbour, but reached far higher prevalence in nearby sheltered inlets. This small-scale spatial segregation is unexpected as shorebird definitive hosts can disperse trematode eggs across wide geographical areas, which should result in a homogeneous mixing of the species on small geographical scales. Possible explanations for this spatial segregation of the species include sampling artefacts, local adaptation by first intermediate hosts, environmental conditions, and site fidelity of the definitive hosts.


Zootaxa ◽  
2011 ◽  
Vol 2754 (1) ◽  
pp. 27 ◽  
Author(s):  
MARC RIUS ◽  
PETER R. TESKE

Pyura stolonifera is a large solitary ascidian found in Africa, Australasia and South America. The taxonomic status of different populations of this species is disputed, especially since there is evidence for several distinct morphological and genetic units that point towards the existence of multiple cryptic species. While some researchers still recognize P. stolonifera as a single species, others treat the different populations as distinct species. Here, we present a revision of the P. stolonifera species complex based on the examination of samples from all regions where there are reliable reports of this taxon. We recognize four species that are both morphologically and genetically distinct, one of which is new to science and is formally described here. This species is morphologically distinct from the other three members of the species complex in terms of the colour and texture of the tunic, the arrangement of the gonads within the gut and the shape of the dorsal tubercle, among other characters. We name the new species Pyura dalbyi after Dr. J.E. Dalby Jr., whose research on its ecology and distribution provided the incentive for examining this species more closely.


Paleobiology ◽  
1995 ◽  
Vol 21 (2) ◽  
pp. 220-228 ◽  
Author(s):  
Charles G. Wray ◽  
Neil H. Landman ◽  
W. Bruce Saunders ◽  
James Bonacum

Despite exhaustive investigation of present-day Nautilus, the phylogenetic relationships of the five or six recognized species within this genus remain unclear. Mitochondrial and nuclear DNA sequence data plus a suite of morphological characters are used to investigate phylogenetic relationships. Systematic analysis of the morphological variation fails to characterize described species as independent lineages. However, DNA sequence analysis indicates that there are three geographically distinct clades consisting of western Pacific, eastern Australian/Papua-New Guinean, and western Australian/Indonesian forms. The morphologically and genetically distinct species Nautilus scrobiculatus falls outside the three geographically recognized assemblages. Members of the genus Nautilus also exhibit low levels of sequence divergence. All these data suggest that Nautilus is currently undergoing diversification, which may have begun only several million years ago. These data also suggest that some of the morphological features used to define Nautilus species may simply represent fixed variations in isolated populations within the same species.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ying Zhang ◽  
Yupei Zhou ◽  
Wei Sun ◽  
Lili Zhao ◽  
D. Pavlic-Zupanc ◽  
...  

The genus Botryosphaeria includes more than 200 epithets, but only the type species, Botryosphaeria dothidea and a dozen or more other species have been identified based on DNA sequence data. The taxonomic status of the other species remains unconfirmed because they lack either morphological information or DNA sequence data. In this study, types or authentic specimens of 16 “Botryosphaeria” species are reassessed to clarify their identity and phylogenetic position. nuDNA sequences of four regions, ITS, LSU, tef1-α and tub2, are analyzed and considered in combination with morphological characteristics. Based on the multigene phylogeny and morphological characters, Botryosphaeria cruenta and Botryosphaeria hamamelidis are transferred to Neofusicoccum. The generic status of Botryosphaeria aterrima and Botryosphaeria mirabile is confirmed in Botryosphaeria. Botryosphaeria berengeriana var. weigeliae and B. berengeriana var. acerina are treated synonyms of B. dothidea. Botryosphaeria mucosa is transferred to Neodeightonia as Neodeightonia mucosa, and Botryosphaeria ferruginea to Nothophoma as Nothophoma ferruginea. Botryosphaeria foliicola is reduced to synonymy with Phyllachorella micheliae. Botryosphaeria abuensis, Botryosphaeria aesculi, Botryosphaeria dasylirii, and Botryosphaeria wisteriae are tentatively kept in Botryosphaeria sensu stricto until further phylogenetic analysis is carried out on verified specimens. The ordinal status of Botryosphaeria apocyni, Botryosphaeria gaubae, and Botryosphaeria smilacinina cannot be determined, and tentatively accommodate these species in Dothideomycetes incertae sedis. The study demonstrates the significance of a polyphasic approach in characterizing type specimens, including the importance of using of DNA sequence data.


Zootaxa ◽  
2021 ◽  
Vol 5052 (2) ◽  
pp. 111-129
Author(s):  
PETR G. GARIBIAN ◽  
LA-ORSRI SANOAMUANG ◽  
ALEXEY A. KOTOV

It is widely accepted among the Cladocera (Crustacea) taxonomists that almost all “cosmopolitan” taxa are represented by some un-revised complexes of cryptic species. But many macro taxa of the cladocerans are still unrevised. The aim of this work is to analyze the taxonomic status of Oriental populations of the genus Bosminopsis Richard, 1895 (Anomopoda: Bosminidae) based on morphological characters. We have studied populations from India, Myanmar, Cambodia, Thailand, Laos, Vietnam, Philippines, Malaysia and Papua New Guinea and concluded that Oriental populations belong to a single species, Bosminopsis africanus (Daday, 1908), initially described from Africa. Analysis of literature data confirms that is widely distributed through whole Oriental zone. A single large mucro, or the mucro accompanied by an additional small spine in both sexes, is the main trait which differentiates B. africanus from B. zernowi Linko, 1901 distributed in more northern regions of Eurasia.  


Phytotaxa ◽  
2020 ◽  
Vol 443 (2) ◽  
pp. 179-188
Author(s):  
BEATRIZ DO NASCIMENTO VALENTE ◽  
JOSÉ FERNANDO A. BAUMGRATZ ◽  
VITOR HUGO MAIA

(Nomenclatural novelties in Miconieae (Melastomataceae): new synonym and typifications). This contribution provides diagnostic morphological characters, geographic distribution data, synonymizations and typifications for three species of Miconieae. We clarify the taxonomic status of Clidemia raddiana as a new synonym for Miconia capilliflora and designate its lectotype. For Miconia capillaris and Miconia leptopus, we provide nomenclatural adjustments, due to the similarity of the epithets and morphological characteristics. We also designate a lectotype and a neotype, respectively, for these two species.


2007 ◽  
Vol 19 (1) ◽  
pp. 71-82 ◽  
Author(s):  
Fabian A. Seymour ◽  
Peter D. Crittenden ◽  
Nora Wirtz ◽  
Dag O. Øvstedal ◽  
Paul S. Dyer ◽  
...  

Usnea species of the Neuropogon group are amongst the most widespread and abundant macrolichens in Antarctic regions. Four principal species, U. antarctica, U. aurantiaco-atra, U. sphacelata and U. subantarctica, have been described on morphological grounds. However, identification to species level is often difficult and atypical morphologies frequently arise. Over 400 specimens were collected on the Antarctic Peninsula and Falkland Islands. Both morphological and molecular characters (ITS and RPB1) were used to compare samples to clarify taxonomic relationships. Morphological characteristics used included presence of apothecia, apothecial rays, soredia, papillae, fibrils, pigmentation and the diameter of the central axis as a proportion of branch diameter. Results revealed a very close relationship between U. antarctica and U. aurantiaco-atra, suggesting that they might constitute a species pair or be conspecific. Usnea sphacelata was comprised of at least two genetically distinct groups with no clear differences in morphology. One group included the first reported fertile specimen of this species. Usnea subantarctica was phylogenetically distinct from the other main Antarctic Usnea species, but clustered with U. trachycarpa. Genetic variation was evident within all species although there was no clear correlation between geographic origin and genetic relatedness. Phylogenetic analyses indicated that species circumscription in the Neuropogon group needs revision, with the principal species being non-monophyletic. None of the morphological characters, or groups of characters, used in this study proved to be completely unambiguous markers for a single species. However, axis thickness was supported as being informative for the identification of monophyletic lineages within the group.


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