Average lifespan
Status: captivity: 6.7 years.
A case study by Tinsley and Tocque has suggested that population dynamics of S. couchii in the desert are governed by the duration and intensity of summer rainfall, the effects of which are recognizable in the growth records of individuals (by analysis of growth rings from bones) and in the age-structure of breeding populations.
Adults of the parasite Pseudodiplorchis americanus infect breeding toads and feed on the host blood during hibernation. Infected toads that emerge from hibernation have smaller fat bodies than those that are uninfected. Fat body weights increase, however, during a period of foraging; there is no measurable effect after two weeks of feeding. A case study by Tocque has suggested that some toads might not breed or survive hibernation due to this parasitic infection. Therefore, there is potential for these parasites to regulate host populations.
Scaphiopus couchii has a stout body and is 2.25 to 3.5 inches (5.6 to 8.8 cm). The color varies from bright green-yellow to brown-yellow. The dorsal surface is mottled with dark green, brown, or black markings, and the dark markings are more extensive in females. The ventral surface is white. The skin is covered with many small warts. The hind limbs have a single, sickle-shaped tubercle, or spade on the inner surface. The pupils are vertical in bright light.
Range length: 2.25 to 3.5 mm.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry ; radial symmetry
Sexual Dimorphism: sexes colored or patterned differently
In the spring males croak to attract females, calling from the rims of temporary pools.
Communication Channels: visual ; tactile ; acoustic ; chemical
Other Communication Modes: choruses
Perception Channels: visual ; tactile ; acoustic ; chemical
Scaphiopus couchii lives underground in burrows in grassland prairies and mequite savannas. They dig these burrows in soft earth by backing into the ground and digging with hind feet, which are armed with spades. They rock the body as they dig; dirt falls into the burrows on top of the toads. Scaphiopus couchii seeks shelter under fallen logs and is adapted to arid and semi-arid conditions.
Habitat Regions: terrestrial
Terrestrial Biomes: desert or dune ; savanna or grassland
This species is found in the southwestern United States, extending into Mexico (and including the Baja Peninsula).
Scaphiopus couchii eats mostly insects. Scaphiopus couchii survives ten months of hibernation (during which it does not feed) by utilizing stored lipid reserves predominantly concentrated in coelomic fat bodies.
Animal Foods: insects
Primary Diet: carnivore (Insectivore )
Scaphiopus couchii is a significant predator in its ecosystem, keeping many kinds of insects (that bother humans) under control.
Scaphiopus couchii is a significant predator in its ecosystem, keeping many kinds of insects (that bother humans) under control. While S. couchii may not be the typical "laboratory frog", it certainly has research value for the scientific community, especially in the areas of development and adaptations (such as burrowing). Most importantly, S. couchii constitutes a part of the remaining wild animal life of the world and should be appreciated in terms of biodiversity.
Positive Impacts: research and education; controls pest population
The burrows may make land unsuitable for developing and cultivation purposes.
Development - Life Cycle: metamorphosis
Because of the life cycles of Scaphiopus couchii (both aquatic and terrestrial stages), the thin, permeable skin and the underground dwelling, this species is especially sensitive to environmental perturbations. Such environmental problems may include acid rain, increasing ultraviolet irradiation, changes in land and water, and other factors. As always, humans must begin taking greater resonsibility for the world around them.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Scaphiopus couchii (like other frogs and toads) breeds only during the warmer seasons of the year. Breeding takes place from April to September, usually in temporary rain pools or temporary overflow areas. When their eggs are mature, the females enter the water and are clasped by the males in a process called amplexus. As the female lays the eggs, the male discharges seminal fluid containing sperm over the eggs to fertilize them. The jelly layers absorb water and swell after fertilization. The eggs are laid in large masses, usually anchored to grass or plant stems. Eggs hatch within 36 hours and the tadpoles develop quickly. After the tadpole has undergone metamorphosis (30 to 40 days after the eggs have hatched), the adult S. couchii is ready to reproduce.
Breeding season: Breeding takes place from April to September
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (External ); oviparous
There is no parental investment after egg-laying.
Parental Investment: pre-fertilization (Provisioning)
Couch’s spadefoot is a 3 inch, smooth-skinned toad. It can be a greenish, yellowish or olive color with irregular blotches or spots of black, brown or dark green. It has a white belly without markings. At the base of each hind foot is a dark, sickle-shaped keratinous “spade”, hence the name spadefoot. The Couch’s spadefoot does very well in extremely dry conditions in areas with well-drained soils, which are often occupied by creosote bush and mesquite trees. Using the spade on the hind foot, spadefoots can quickly bury themselves in loose, sany soils. Adult spadefoots burrow in the ground to avoid heat. Recently metamorphosed spadefoots may be seen during and immediately after the rainy season in moist places, such as under vegetation, former ponds or moist soil. During this time, young spadefoots need to eat enough food to survive the unfavorable living conditions above the surface of the ground. After eating as much as possible, they too burrow beneath the surface. Breeding may not occur in years with insufficient rainfall. Preying primarily upon beetles, grasshoppers, ants, spiders and termites, a spadefoot can consume enough food in one meal to last an entire year.
Couch's spadefoot toad or Couch's spadefoot (Scaphiopus couchii) is a species of North American spadefoot toad (family Scaphiopodidae).[2] The specific epithet couchii is in honor of American naturalist Darius Nash Couch, who collected the first specimen while on a personal expedition to northern Mexico to collect plant, mineral, and animal specimens for the Smithsonian Institution.[3]
Unlike other toads which have horizontal pupils, spadefoot toads have vertical pupils. On the underside of the hind foot is a hard, dark "spade" that gives spadefoot toads their name. These creatures can grow to be 3.5" in length. These "spades" are used by the toads to burrow into the ground to prevent water loss and hide from predators. There are two spadefoot species in the Sonoran Desert of Arizona and California. Couch's spadefoot toad (Scaphiopus couchi) has a sickle-shaped "spade", whereas the western spadefoot toad (Spea hammondii) has a rounded "spade". Spadefoots are not true toads and should therefore simply be called spadefoots.[4]
Couch's spadefoot toad is native to the United States southwest of southeastern Colorado and central Oklahoma, northern Mexico and the Baja peninsula. They can be found throughout the Sonoran Desert, which includes parts of southern Arizona and California.
Water is a necessary medium for the fertilization of spadefoot eggs, and once the eggs hatch, water also provides a place for tadpoles to mature to the adult stage. Because of the importance of water, spadefoots are active during the wet season spring and summer in the Northern Hemisphere), and remain underground during the dry season (fall and winter). When a summer thunderstorm arrives, the male toads emerge from underground and look for pools of rainwater. When they find water, the males produce a mating call that attracts female toads. New research has shown that females tend to be more attracted to bright-colored males over their dark-colored peers. Thus creating a new aspect in their determination of the male's size and condition.[5] Because the pools of water may be short-lived, mating occurs the first night after rainfall begins.
During reproduction, the male mounts the female and releases sperm to fertilize the eggs, which are deposited in the pools of water in the form of a floating mass. The eggs hatch into tadpoles, which quickly mature into adults. They must reach this stage before the pool of water evaporates, and thus they sometimes mature in as little as 9 days after the eggs are laid. Western spadefoot toads take longer to mature (at least three weeks).
The small pools of water are warmed by the sun, which speeds up the growth of the tadpoles. Tadpoles will eat a variety of foods, such as small insects near the pool and algae, which they scrape off rocks. They also filter microorganisms from the water as it is passed over their gills. Tadpoles gather in wriggling masses, stir up the muck on the bottom of the pool, and filter out the organic nutrients. Unlike most tadpoles, which are exclusively herbivores and filter feeders, spadefoot tadpoles are omnivores. They also eat dead insects and tadpoles, as well as fairy shrimp.
Couch's spadefoot toad or Couch's spadefoot (Scaphiopus couchii) is a species of North American spadefoot toad (family Scaphiopodidae). The specific epithet couchii is in honor of American naturalist Darius Nash Couch, who collected the first specimen while on a personal expedition to northern Mexico to collect plant, mineral, and animal specimens for the Smithsonian Institution.
