the semiarid thornscrub and grasslands of the Tamaulipan mezquital ecoregion. Sheep frogs are secretive and largely fossorial, known to live in the cavities of hollowed out root systems of trees and shrubs, mammal burrows, and pack rat nest. It is capable of burrowing backwards with its hind feet into loose soils, just below the surface during wet periods, and up to a meter in dry seasons. It emerges after heavy rains to breed and occasionally forage at night, and may be found under rocks, logs and fallen palm trees, and other surface debris while soils remain wet. Reproduction: Sheep frogs deposit their eggs between March and September or October. Emergence and mating is typically stimulated by heavy rain, or on occasions the irrigation of fields. Males often call while freely floating on the surface of shallow pools. The call is a sheep-like bleat about two to three seconds in duration. Amplexus is axillary and the eggs are deposited in the water, floating at the surface in loosely attached rafts. Typically (although not exclusively) eggs are deposited in ephemeral pools of rainwater, but also in ponds, marshes, ditches, and cattle tanks. Clutches of about 700 eggs have been reported and they hatch within 12 to 24 hours. The tadpoles are brownish with faint markings on the belly, and some individuals exhibit a mid-dorsal stripe, growing up to 2.7-3.5 cm in total length. Metamorphose occurs after about one month and froglets are 1-1.6 cm snout to vent length. Conservation Although Hypopachus variolosus is a wide-ranging species and common in some areas of its distribution, it is uncommon within its limited range in the US, and it is protected by law in the state of Texas where it is listed as a threatened species. Threats in Texas include fragmentation and loss of habitat due to agriculture and urban expansion. References External links Hypopachus Frogs of North America Amphibians of Belize Amphibians of Costa Rica Amphibians of El Salvador Amphibians of Guatemala Amphibians of Honduras Amphibians of Mexico Amphibians of Nicaragua Amphibians of the United States Amphibians described in 1866 Taxa named by Edward Drinker Cope