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1.
Zootaxa ; 4623(3): zootaxa.4623.3.2, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31716246

RESUMO

New Zealand has a diverse skink fauna, comprising 45 described native species, and at least 15 undescribed taxa, within the single genus Oligosoma Girard, 1857. One of the earliest described, and best known, species is the speckled skink, Oligosoma infrapunctatum (Boulenger 1887). Despite a relatively stable taxonomic history for nearly 114 years, recent molecular work has indicated that O. infrapunctatum represents a species complex, comprising numerous genetically divergent, range restricted taxa. We completed the first stage of a taxonomic revision of O. infrapunctatum, conducting a morphological re-evaluation of existing voucher material, and newly collected specimens, and generated a molecular phylogeny for the species complex. This allowed us to distinguish six species: O. infrapunctatum, two species resurrected from synonymy (O. newmani, O. robinsoni), and three new species (O. salmo sp. nov., O. albornense sp. nov. O. auroraensis sp. nov.). The name bearing type population of O. infrapunctatum has not been located again for at least 130 years: it remains to be rediscovered and may already be extinct. Two of the six species here are considered 'Nationally Critical' (O. albornense sp. nov., O. salmo sp. nov.) under the New Zealand Threat Classification System, the others are Nationally Vulnerable (O. auroraensis sp. nov.) and At Risk-Relict (O. newmani, O. robinsoni). Further taxonomic work will be required to determine the taxonomy of other speckled skink genetic lineages in the South Island, particularly O. aff. infrapunctatum "cobble", O. "Hokitika", O. "Southern North Island" and O. "Westport".


Assuntos
Lagartos , Animais , Nova Zelândia , Filogenia
2.
J Morphol ; 272(9): 1116-30, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21688293

RESUMO

Endemic New Zealand frogs of the genus Leiopelma are from a basal lineage of extant anurans that release defensive secretions onto their skin when disturbed. Here, we characterize the gross anatomy and microscopic structure of the skin of L. archeyi, L. hochstetteri, and L. pakeka using stereoscopic, light and transmission electron microscopy. The terrestrial L. archeyi and L. pakeka possess dimorphic granular glands, categorized as type I and II, based on their frequency and morphological traits, whereas the semi-aquatic L. hochstetteri lacks type I glands. This is the first report of differential dimorphism in anurans of the same genus. This dimorphism could be interpreted as an adaptation to different physiological or ecological needs of these species. However, species within this ancient genus share similar general gland morphology with other anurans, namely, a secretory unit containing storage granules ensheathed by myoepithelial cells. Type I glands are ellipsoid, large and contain a homogeneous mass of electron-dense granules (1.8 ± 0.08 µm in diameter). Type II glands are round and contain larger heterogeneous granules (4.06 ± 0.16 µm) of varying densities. Exposure to noradrenaline causes the contraction of myoepithelial cells, resulting in bulk discharge of type I glands through the epidermal duct onto the skin surface. Differential release of secretions from dimorphic glands may be indicative of their functional specialisation in antipredatory or regulative roles. Mass spectrometric techniques were used to de novo sequence peptides present in the skin secretions of Leiopelma species. A total of 30 previously undescribed peptides from Leiopelma species were fully or partially sequenced. These peptides exhibited no similarity to any known compounds.


Assuntos
Anuros/anatomia & histologia , Sequência de Aminoácidos , Animais , Anuros/metabolismo , Feminino , Masculino , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Nova Zelândia , Norepinefrina/farmacologia , Peptídeos/química , Peptídeos/metabolismo , Vesículas Secretórias/química , Vesículas Secretórias/efeitos dos fármacos , Vesículas Secretórias/ultraestrutura , Pele/anatomia & histologia , Pele/ultraestrutura
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