Genetic differentiation, taxonomy and conservation of Australasian teals Anas spp.

Abstract

Australasian teal consist of five taxa (Anas gracilis, A. castanea, A. chlorotis, A. aucklandica and A. nesiotis) whose taxonomic identities and relationships have been uncertain. Analysis of variation at 14 allozyme loci indicates limited but clear divergence of New Zealand taxa (A. chlorotis, A. aucklandica, A. nesiotis), in agreement with previous studies of morphological variation. The New Zealand taxa are 'terminal and evolutionarily independent units' that clearly meet the criteria for specific recognition in line with the phylogenetic species concept (PSC). Because each is also geographically restricted and has small world population size, specific recognition supports increased conservation status for each. The three New Zealand species do not form a sister group with A. castanea, as previously hypothesized; instead, A. castanea and A. gracilis are sister taxa.