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1.
BMC Ecol Evol ; 23(1): 57, 2023 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-37752477

RESUMEN

According to the IUCN Red List the anadromous houting Coregonus oxyrinchus is categorized as 'extinct'. However, this extinct status might be incorrect because taxonomic difference between C. oxyrinchus and the closely related C. lavaretus is based on a disputable morphological comparison. Also, phylogenetic studies on mtDNA only focused on recent obtained coregonids. We are the first to perform a mtDNA analysis on both historic and recent specimens, including the syntype specimen which was used for species description by Linnaeus originally. Two primer pairs for mitochondrial CytB and ND3 were used to extract sequences for phylogenetic analysis. Sequences from 14 out of 21 C. oxyrinchus museum specimens were successfully obtained and compared with sequences from recent obtained C. lavaretus. The sequences were combined with GenBank data from a previous phylogenetic study on houting to create a phylogenetic tree and two minimum spanning haplotype networks. Results show that C. oxyrinchus and C. lavaretus form a clade with limited genetic variation. Low bootstrap values also show weak support for geographical patterns in distribution of mitochondrial haplotypes. Statistical analysis of the haplotype networks also shows that historic and recent specimens are similar species. Our results suggest that C. oxyrinchus is a junior synonym of C. lavaretus. A definitive taxonomic revision could not be made because only CytB sequencing was successful for the syntype specimen. We discuss taxonomic consequences and the species-specific focus in nature conservation. We propose a shift in nature conservation to a more functional approach based on traits rather than species.


Asunto(s)
Museos , Salmonidae , Animales , Filogenia , Salmonidae/genética , ADN Mitocondrial/genética
2.
Mol Phylogenet Evol ; 79: 12-22, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24952316

RESUMEN

Past climatic and tectonic events are believed to have strongly influenced species diversity in the Eastern Afromontane Biodiversity Hotspot. We investigated the phylogenetic relationships and historical biogeography of the East African genus Atheris (Serpentes: Viperidae), and explored temporal and spatial relationships between Atheris species across Africa, and the impact of palaeoclimatic fluctuations and tectonic movements on cladogenesis of the genus. Using mitochondrial sequence data, the phylogeny of East African species of Atheris shows congruent temporal patterns that link diversification to major tectonic and aridification events within East Africa over the last 15million years (my). Our results are consistent with a scenario of a delayed direct west-east colonisation of the Eastern Arc Mountains of Atheris by the formation of the western rift. Based on the phylogenetic patterns, this terrestrial, forest-associated genus has dispersed into East Africa across a divided route, on both west-southeasterly and west-northeasterly directions (a C-shaped route). Cladogenesis in the Eastern Arc Mountains and Southern Highlands of Tanzania corresponds to late Miocene and Plio-Pleistocene climatic shifts. Taxonomically, our data confirmed the monophyly of Atheris as currently defined, and reveal four major East African clades, three of which occur in discrete mountain ranges. Possible cryptic taxa are identified in the Atheris rungweensis and A. ceratophora clades.


Asunto(s)
Clima , Especiación Genética , Filogenia , Viperidae/clasificación , África Oriental , Animales , ADN Mitocondrial/genética , Bosques , Modelos Genéticos , Análisis de Secuencia de ADN
3.
Dis Aquat Organ ; 102(3): 187-94, 2013 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-23446968

RESUMEN

Amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) has been hypothesised to be an indigenous parasite of African amphibians. In Cameroon, however, previous surveys in one region (in the northwest) failed to detect this pathogen, despite the earliest African Bd having been recorded from a frog in eastern Cameroon, plus one recent record in the far southeast. To reconcile these contrasting results, we present survey data from 12 localities across 6 regions of Cameroon from anurans (n = 1052) and caecilians (n = 85) of ca. 108 species. Bd was detected in 124 amphibian hosts at 7 localities, including Mt. Oku, Mt. Cameroon, Mt. Manengouba and lowland localities in the centre and west of the country. None of the hosts were observed dead or dying. Infected amphibian hosts were not detected in other localities in the south and eastern rainforest belt. Infection occurred in both anurans and caecilians, making this the first reported case of infection in the latter order (Gymnophiona) of amphibians. There was no significant difference between prevalence and infection intensity in frogs and caecilians. We highlight the importance of taking into account the inhibition of diagnostic qPCR in studies on Bd, based on all Bd-positive hosts being undetected when screened without bovine serum albumin in the qPCR mix. The status of Bd as an indigenous, cosmopolitan amphibian parasite in Africa, including Cameroon, is supported by this work. Isolating and sequencing strains of Bd from Cameroon should now be a priority. Longitudinal host population monitoring will be required to determine the effects, if any, of the infection on amphibians in Cameroon.


Asunto(s)
Anfibios , Quitridiomicetos/aislamiento & purificación , Micosis/veterinaria , Animales , Camerún/epidemiología , Micosis/epidemiología , Micosis/microbiología , Vigilancia de la Población
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