Spea multiplicata

Tanner (1989) and Wiens and Titus (1991) recognized Spea as distinct from Scaphiopus, within which it was previously regarded as a subgenus (Crother 2017). Fouquette and Dubois (2014) cited unpublished data on geographic call differences that might suggest multiple species within this binominal and recognized two subspecies although it is not clear what the relation of the call types with the subspecies is, if any (Frost 2020).

Regarded as conspecific with S. hammondii until 1976 (Brown 1976). In Tanner (1989), the name multiplicatus (as a subspecies) is associated with populations in the mountains and plateaus of Chihuahua and Durango; southwestern U.S. populations that recently have been referred to as S. multiplicata are called S. hammondii stagnalis (hence Scaphiopus [or Spea] stagnalis if regarded as a species distinct from populations of hammondii in California and Baja California). Sometimes hybridizes with S. bombifrons (Sattler 1985).

Garcia-Paris et al. (2003) used mtDNA to examine the phylogentic relationships of Pelobatoidea and found that the family Pelobatidae, as previously defined, is not monophyletic (Pelobates is sister to Megophryidae, not to Spea/Scaphiopus). They split the Pelobatidae into two families: Eurasian spadefoot toads (Pelobates), which retain the name Pelobatidae, and North American spadefoot toads (Scaphiopus, Spea), which make up the revived family Scaphiopodidae.

Range extends from southeastern Utah, southern Colorado, and northern Oklahoma south through Arizona, New Mexico, and western Texas in the United States, to Guerrero and Oaxaca (Stebbins 1985, Conant and Collins 1991) in Mexico. Elevational range extends up to about 2,470 meters in some areas.

Represented by many and/or large occurrences throughout most of the range.

In some areas, local populations have been eliminated or reduced by agricultural development and other habitat alterations, but most habitat is not significantly threatened.