Molecular data from contemporary and historical collections reveal a complex story of cryptic diversification in the Varanus (Polydaedalus) niloticus Species Group.
Mol Phylogenet Evol
; 94(Pt B): 591-604, 2016 Jan.
Article
em En
| MEDLINE
| ID: mdl-26475616
ABSTRACT
Previous studies of color pattern, tongue pigmentation, and scale counts have been used to distinguish two species of semiaquatic varanids in Africa, but these findings have yet to be tested with molecular data. The Varanus (Polydaedalus) niloticus Species Group is comprised of the Nile monitor (V. niloticus) and the Ornate monitor (V. ornatus). Due to the high rate of exploitation of both species for bushmeat, the leather industry, and the pet trade, a clear understanding of the taxonomy and genetic partitioning is necessary for effective management. Here we utilize a multilocus approach, consisting of mitochondrial and nuclear markers, totaling 4251 bp, as well as microsatellite loci to assess the taxonomic validity and intraspecific evolutionary patterns within the V. niloticus Species Group. By incorporating historical specimens from museum collections as well as contemporary samples, we obtained range-wide coverage for both species across Africa. Concordant results from various approaches all suggest that V. ornatus does not represent a distinct monophyletic group. Our analyses recovered three genetic clades within V. niloticus, representing western, northern, and southern lineages. The western clade was found to diverge first, around 7.7 mya (95% HPD 4.6-11.0 mya) and exhibits 8.4% and 8.7% uncorrected sequence divergence between the northern and southern V. niloticus clades, respectively. This geographically separate lineage corresponds to previous descriptions of Tupinambis stellatusDaudin (1802). These findings not only call for taxonomic revision of this species group, but also shed light on the biogeographic history of Africa as well as aid in the management planning of varanids and other co-distributed African species.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Variação Genética
/
Lagartos
Limite:
Animals
País/Região como assunto:
Africa
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article