Jc. Meyran et al., TAXONOMIC STATUS AND PHYLOGENETIC-RELATIONSHIPS OF SOME SPECIES OF THE GENUS GAMMARUS (CRUSTACEA, AMPHIPODA) DEDUCED FROM MITOCHONDRIAL-DNASEQUENCES, Molecular phylogenetics and evolution, 8(1), 1997, pp. 1-10
Mitochondrial DNA nucleotide sequence analysis was used to determine t
he extent of genetic differentiation among six species of the genus Ga
mmarus (Crustacea, Amphipoda) common in France (G. fossarum, G. pulex,
G. Lacustris, G. wautieri, G. roeseli, G. marinus). From 23 different
populations, 104 specimens were compared to examine their taxonomic s
tatus and their phylogenetic relationships. Nucleotide sequences for a
376-base segment of the cytochrome c oxidase subunit I (COI) gene wer
e obtained through direct sequencing of amplified DNA. The strong sequ
ence variability found at the interspecific level, generally masked by
morphological or ecological similarities, is consistent with that obs
erved for other crustaceans and supports existing species classificati
ons. A high level of genetic variation was observed at the intraspecif
ic level, suggesting that the COI gene will be a powerful marker for a
mphipod population biology. Based on the mitochondrial DNA results, we
propose a phylogenetic hypothesis of the relationships among the six
studied species, which is discussed in biogeographic and evolutionary
terms. (C) 1997 Academic Press.