This family includes Longspurs and Snow Buntings. They are mainly found in North America and Eurasia. There are six species divided over three genera, of which two show hybridization (Calcarius and Plectrophenax), for instance Chestnut-collared Longspur (C. ornatus) x McCown’s Longspur (C. mccownii) (Sibley & Pettingill, 1955). Even intergeneric hybridization has been documented, namely between Snow Bunting (P. nivalis) and Lapland Longspur (C. lapponicus) in Canada (Macdonald et al., 2012). Snow Bunting is also known to hybridize with McKay’s buntings (P. hyperboreus) (Sealy, 1969). Coalescent analysis indicated asymmetric gene flow from McKay’s bunting into Snow Bunting, but it is not possible to rule out retained ancestral polymorphisms (Maley & Winker, 2010).
Macdonald, C. A., Martin, T., Ludkin, R., Hussell, D. J., Lamble, D. & Love, O. P. (2012). First Report of a Snow Bunting× Lapland Longspur Hybrid. Arctic, 344-348.
Maley, J. M. & Winker, K. (2010). Diversification at high latitudes: speciation of buntings in the genus Plectrophenax inferred from mitochondrial and nuclear markers. Molecular Ecology 19, 785-797.
Sealy, S. G. (1969). Apparent hybridization between snow bunting and McKay’s bunting on St. Lawrence Island, Alaska. The Auk, 350-351.
Sibley, C. G. & Pettingill, O. S. (1955). A hybrid longspur from Saskatchewan. The Auk, 423-425.