Mitochondrial gene markers for the hybridizing toads Bufo microscaphus andBufo woodhousii in Arizona

Three restriction site markers from the mitochondrial genome are described for the toads Bufo microscaphus and B. woodhousii. Markers were resolved fr om DNA sequence data representing segments of cytochrome b (cytb) and 16S r ibosomal genes. Two diagnostic restriction sites (BsmA I; SfaN I) character ize B. microscaphus for cytb, whereas a third restriction site (Tsp509 I) d istinguishes B. woodhousii for 16S. Restriction digests of PCR-amplified cy tb and 16S segments provide an economical, nondestructive assay with which to identify mtDNA. haplotypes far these toads and their hybrids. The mtDNA markers complement diagnostic allozyme and call characters, offering an add itional approach to examine hybridization between the two species in centra l Arizona.