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1.
J Evol Biol ; 19(4): 1139-48, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16780514

RESUMO

Laboratory mate choice experiments have confirmed species status for cichlid fish in the African Great Lakes that differ in colour and little else. Colour differences between allopatric populations of the South American cichlid genus Apistogramma are known for many species, yet the status of such populations has not been previously tested. Analysis of the genetic relationships and mate choice characteristics of populations previously described as Apistogramma caetei from eastern Amazonia indicates genetic differentiation into at least three allopatric lineages, which also show strong prezygotic isolation through female mate choice, confirming them as Biological species. If future studies confirm that this result is indicative of a general trend, the species richness of the South American cichlid fishes may presently be seriously underestimated.


Assuntos
Ciclídeos/fisiologia , Cor , Reprodução , Animais , Feminino , Masculino , Comportamento Sexual Animal , Especificidade da Espécie
2.
Med Vet Entomol ; 18(1): 25-37, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15009443

RESUMO

The bloodsucking adult females of Phlebotomus perniciosus Newstead and P. longicuspis Nitzulescu (Diptera: Psychodidae) are important vectors of the protozoan Leishmania infantum Nicolle (Kinetoplastida: Trypanosomatidae) in western Mediterranean countries. The species status of the two phlebotomine sandflies was assessed, along with the epidemiological implications. Individual sandflies from three Moroccan Rif populations were characterized morphologically, isoenzymatically (by the isoelectrofocusing of alleles at the polymorphic enzyme loci of HK, GPI and PGM), and by comparative DNA sequence analysis of a fragment of mitochondrial Cytochrome b (mtDNA). By reference to the character profiles of specimens from other locations, including southern Spain and the type-locality countries, the Moroccan flies were placed in three lineages: first, the lineage of P. perniciosus, which contained two mtDNA sublineages, one (pnt) widely distributed and associated with the morphology of the male types from Malta, and the other (pna) associated with a P. longicuspis-like male morphology; second, the lineage of P. longicuspis sensu stricto, including typical forms from Tunisia; and third, a new sibling species of P. longicuspis. The mtDNA sublineage (pnt) of typical P. perniciosus was also found in some P. longicuspis from Morocco, indicating interspecific hybridization. The typical race of P. perniciosus occurs in Italy as well as in Malta, Tunisia and Morocco. It is replaced in southern Spain by the Iberian race (with the pni mtDNA sublineage). The discovery of interspecific gene introgression and a new sibling species mean that previous records of the two morphospecies do not necessarily reflect their true vectorial roles or geographical and ecological distributions.


Assuntos
DNA Mitocondrial/genética , Phlebotomus/enzimologia , Phlebotomus/genética , Alelos , Animais , Citocromos b/química , Citocromos b/genética , DNA Mitocondrial/química , Feminino , Genitália Masculina/ultraestrutura , Glucose-6-Fosfato Isomerase/genética , Glucose-6-Fosfato Isomerase/metabolismo , Hexoquinase/genética , Hexoquinase/metabolismo , Focalização Isoelétrica , Isoenzimas , Masculino , Marrocos , Phlebotomus/anatomia & histologia , Fosfoglucomutase/genética , Fosfoglucomutase/metabolismo , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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