05/03/2012
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Tanager transfer underlines massive radiation

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Blue-black Grassquit, like this bird photographed near Rio Paranapanema, Piraju, São Paulo, Brazil, is a tanager not a bunting, it seems. Photo: Dario Sanches (commons.wikimedia.org).
Blue-black Grassquit, like this bird photographed near Rio Paranapanema, Piraju, São Paulo, Brazil, is a tanager not a bunting, it seems. Photo: Dario Sanches (commons.wikimedia.org).

The South American Classification Committee has approved a proposal to move many specialised Neotropical genera to the tanager family Thraupidae from their former home in the Emberizidae, the buntings and American sparrows.


Though a linear sequence has yet to be decided, this will leave a more defensible Emberizid order for the continent, as well as a richer tanager assemblage. The transfers are largely based on the accumulated genetic studies of the last 10 years or so, and some have already been enacted individually while others have been suspected on a morphological basis for some time.


The genera now ensconced in the Thraupidae are (with the English names of the more well-known forms in parentheses): Porphyrospiza , Phrygilus (sierra finches), Melanodera, Haplospiza, Idiopsar, Diuca, Lophospingus, Poospiza (warbling-finches), Compsospiza, Sicalis, Emberizoides (grass-finches), Embernagra, Volatinia (Blue-black Grassquit), Sporophila (seedeaters), Oryzoborus (seed-finches), Dolospingus, Catamenia, Coryphospingus, Rhodospingus, Gubernatrix, Camarhynchus, Certhidea (Warbler Finch), Coereba (bananaquits),  Euneornis (Orangequit), Geospiza (Darwin's finches), Loxigilla (Antillean bullfinches), Loxipasser, Melanospiza, Melopyrrha, Pinaroloxias (Cocos Finch),  Platyspiza,  Tiaris (true grassquits) and Parkerthraustes.


As well as affirming the sheer extent of the evolutionary radiation of the tanager lineage, the new arrangement is still a work in progress. A comprehensive analysis of Neotropical seedeaters is still awaited, and there are several genera which are currently of uncertain affinity, and may or may not be tanagers, but are removed from the Emberizidae accordingly:  Donacospiza (Long-tailed Reed-finch), Piezorhina (Cinereous finch), Xenospingus (Slender-billed Finch), Incaspiza (Little Inca-finch), Charitospiza (Coal-crested Finch) and Coryphaspiza (Black-masked Finch); at least one or two  of these forms may well deserve their own family.


This wholesale move of a large number of former sparrows and buntings t o he tanagers is likely to be adopted by most authorities worldwide in the near future.