Phylogeny of Thylamys (Didelphimorphia, Didelphidae) species, with special reference to Thylamys karimii

The genus Thylamys Gray, 1843 lives in the central and southern portions of South America inhabiting open and shrub-like vegetation, from prairies to dry forest habitats in contrast to the preference of other Didelphidae genera for more mesic environments. Thylamys is a speciose genus including T. elegans (Waterhouse, 1839), T. macrurus (Olfers, 1818), T. pallidior (Thomas, 1902), T. pusillus (Desmarest, 1804), T. venustus (Thomas, 1902), T. sponsorius (Thomas, 1921), T. cinderella (Thomas, 1902), T. tatei (Handley, 1957), T. karimii (Petter, 1968), and T. velutinus (Wagner, 1842) species. Previous phylogenetic analyses in this genus did not include the Brazilian species T. karimii, which is widely distributed in this country. In this study, phylogenetic analyses were performed to establish the relationships among the Brazilian T. karimii and all other previously analyzed species. We used 402-bp fragments of the mitochondrial cytochrome b gene, and the phylogeny estimates were conducted employing maximum parsimony (MP), maximum likelihood (ML), Bayesian (BY), and neighbor-joining (NJ). The topologies of the trees obtained in the different analyses were all similar and pointed out that T. karimii is the sister taxon of a group constituted of taxa from dry and arid environments named the dryland species. The dryland species consists of T. pusillus, T. pallidior, T. tatei, and T. elegans. The results of this work suggest five species groups in Thylamys. In one of them, T. velutinus and T. kariimi could constitute a sister group forming one Thylamys clade that colonized Brazil.

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Discovery of a new mammal species (Soricidae: Eulipotyphla) from Narcondam volcanic island, India

Scientific Reports ◽

10.1038/s41598-021-88859-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Manokaran Kamalakannan ◽

Chandrakasan Sivaperuman ◽

Shantanu Kundu ◽

Govindarasu Gokulakrishnan ◽

Chinnadurai Venkatraman ◽

...

Keyword(s):

New Species ◽

Phylogenetic Analyses ◽

Genetic Distances ◽

Medium Size ◽

Mitochondrial Cytochrome ◽

Volcanic Island ◽

Mammal Species ◽

Molecular Approaches ◽

Mitochondrial Cytochrome B ◽

Mitochondrial Cytochrome B Gene

AbstractWe discovered a new Crocidura species of shrew (Soricidae: Eulipotyphla) from Narcondam Island, India by using both morphological and molecular approaches. The new species, Crocidura narcondamica sp. nov. is of medium size (head and body lengths) and has a distinct external morphology (darker grey dense fur with a thick, darker tail) and craniodental characters (braincase is rounded and elevated with weak lambdoidal ridges) in comparison to other close congeners. This is the first discovery of a shrew from this volcanic island and increases the total number of Crocidura species catalogued in the Indian checklist of mammals to 12. The newly discovered species shows substantial genetic distances (12.02% to 16.61%) to other Crocidura species known from the Indian mainland, the Andaman and Nicobar Archipelago, Myanmar, and from Sumatra. Both Maximum-Likelihood and Bayesian phylogenetic inferences, based on mitochondrial (cytochrome b) gene sequences showed distinct clustering of all included soricid species and exhibit congruence with the previous evolutionary hypothesis on this mammalian group. The present phylogenetic analyses also furnished the evolutionary placement of the newly discovered species within the genus Crocidura.

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Molecular systematics of Malagasy poison frogs in the Mantella betsileo and M. laevigata species groups

Zootaxa ◽

10.11646/zootaxa.1501.1.2 ◽

2007 ◽

Vol 1501 (1) ◽

pp. 31-44 ◽

Cited By ~ 4

Author(s):

FALITIANA C.E. RABEMANANJARA ◽

ANGELICA CROTTINI ◽

YLENIA CHIARI ◽

FRANCO ANDREONE ◽

FRANK GLAW ◽

...

Keyword(s):

Sister Group ◽

Sister Group Relationship ◽

Undescribed Species ◽

Poison Frogs ◽

North West ◽

North East ◽

The North ◽

Mitochondrial Cytochrome B ◽

Mitochondrial Cytochrome B Gene ◽

Species Groups

Malagasy poison frogs of the genus Mantella with its 16 species are currently sub-divided into 5 major groups. Of these, the Mantella betsileo group is traditionally understood as containing four species, Mantella betsileo, M. expectata, M. viridis and M. manery, while the M. laevigata group is considered to be monospecific. A phylogenetic analysis of samples from multiple localities of all species in these two groups, based on sequences of the mitochondrial cytochrome b gene, shows the existence of several well-distinct clades in what is currently considered to be Mantella betsileo: (1) central-western populations from Kirindy, Isalo, and near Antsirabe close to the Betsileo region, to which the name M. betsileo is to be applied, (2) populations of the north-east and north-west, which are closely related to M. viridis and to which the name M. ebenaui is to be applied, and (3) a clade from southernmost Madagascar and from the Tsingy de Bemaraha, which is sister to M. expectata and furthermore includes important intra-clade variation, therefore probably representing one or two undescribed species. Our data also support a large genetic distance of M. manery to all other species and its probable sister-group relationship to the sympatric M. laevigata; M. manery is consequently transferred from the M. betsileo group to the M. laevigata group.

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