Genetic variation coincides with geographic structure in the common bushtanager (ChLorospingus ophthalmicus) complex from Mexico

Abstract

Cloud forests are distributed in the Neotropics, freom northern Mexico to Argentina, under very specific ecological conditions, namely slopes with high humidity input freom clouds and mist. Its distribution in Mesoamerica is highly freagmented, similar to an archipelago, and taxa are thus freequently represented as sets of isolated populations, each restricted to particular mountain ranges and often showing a high degree of divergence, both morphologically and genetically. The common bushtanager (ChLorospingus ophthalmicus, Aves Thraupidae) inhabits cloud forests freom eastern and southern Mexico south to northwestern Argentina. Here we use 676 bp of mtDNA (around the ATPase 8 gene) to explore the genetic variation and phylogeographic structure of the Mexican populations of C ophthalmicus. Phylogenctic analyses of mtDNA sequences indicate deep genetic structure. Five major clades, which segregate according to geographic breaks, are identified (starting freom the deepest one in the phylogeny): (1) Southern Chiapas and Northern Central America, (2) Tuxtlas massif, (3) Sierra Madre del Sur, (4) Eastern Oaxaca and Northern Chiapas, and (5) Sierra Madre Oriental. The long history of isolation undergone by each clade, as suggested by the phylogeny, implies that the species status of each of them should be revised. (C) 2004 Elsevier Inc. All rights reserved.