Eastern Narrow-mouthed Toad (Gastrophryne carolinensis)
Description and Morphological Characteristics
Eastern Narrow-mouthed Toads are small, stout-bodied frogs that range from 7/8 to 1 ½ inches in length. They have small heads with a pointed snout and lack ear holes. Color for this species can vary from gray to brown and reddish in some areas, and can even change based on environment or activity. Light colored dorsolateral stripes are usually present but obscured by heavy mottling which continues onto the ventral side of the body. A distinguishing characteristic for all species of narrow-mouthed toads is the fold of skin across the back of the head just behind the eyes. Each hind foot has a single enlarged tubercle, or spade, and the toes on the hindlimbs are not webbed.
Range
This species ranges from Maryland, south to Florida and the Keys, and west to Missouri and east Texas. Disjunct populations can be found north of their range in southern Iowa, Illinois, and southeast Nebraska. Eastern Narrow-mouthed Toads have been introduced on the banks of the Little and Great Bahama, and on the Cayman Islands.
Habitat and Feeding
These small frogs can inhabit a wide range of environments but require ample moisture and shelter, often living near bodies of water. They can be found under logs, boards, vegetative debris, and usually burrow into softer ground. This species can adapt to urban environments so long as the requirements are met. Their diet consists mostly of ants but have also been observed feeding on other insects such as termites and small beetles. A benefit of their small pointed snout is the ability to successfully forage for ants directly at the mound and the fold of skin on the back of their head can be moved forward to keep any insects from attacking the eyes.
Breeding and Reproduction
The breeding season commences with rains and occurs from March to October, but is restricted to the summer months in the northern part of the range. Males can be heard calling the most on rainy nights and usually stay sheltered within clumps of plants or grasses with their bodies floating free and forearms resting on debris. The advertisement call is a bleating sound, similar to that of a sheep or goat, and lasts anywhere from 1-4 seconds. The short nasal-y call has small pulses that are not easily heard, but can be seen well in the call structure. They utilize both temporary and permanent bodies of water but do best in shallow, fishless, temporary ponds. Females lay their eggs as a film on the surface of the water and tadpoles can metamorphose in 20-70 days.
Conservation
The Eastern Narrow-mouthed Toad is common throughout most of its range but declines have been reported in east Texas, likely a result of habitat loss. This species is not under federal protection but is included in the Texas Parks and Wildlife Black List.
Pertinent References
Makowsky, R., Chesser, J., and Rissler, L. J. 2009. A striking lack of genetic diversity across the wide-ranging amphibian Gastrophryne carolinensis (Anura: Microhylidae). Genetica 135:169-183.
McAllister, C. T., and Bursey, C. R. 2005. Endoparasites of the eastern narrowmouth toad, Gastrophryne carolinensis (Anura: Microhylidae), from northwestern Louisiana and northeastern Texas, U.S.A. Comparative Parasitology 72:124-128.
Mitchell, J. C., and Lannoo, M. J. 2005. Eastern Narrow-mouthed Toad. Pp. 501-503 in M. J. Lannoo (Ed.), Amphibian Declines: The Conservation Status of United States Species. University of California Press, USA.
Saenz, D., Fitzgerald, L.A., Baum, K.A., and Conner, R.N. 2006. Abiotic Correlates of Anuran Calling Phenology: The Importance of Rain, Temperature, and Season. Herpetological Monographs 20:64-82.
Account Author: Hailey Hester
Photos: James Childress
Edited by Christopher Schalk
Eastern Narrow-mouthed Toads are small, stout-bodied frogs that range from 7/8 to 1 ½ inches in length. They have small heads with a pointed snout and lack ear holes. Color for this species can vary from gray to brown and reddish in some areas, and can even change based on environment or activity. Light colored dorsolateral stripes are usually present but obscured by heavy mottling which continues onto the ventral side of the body. A distinguishing characteristic for all species of narrow-mouthed toads is the fold of skin across the back of the head just behind the eyes. Each hind foot has a single enlarged tubercle, or spade, and the toes on the hindlimbs are not webbed.
Range
This species ranges from Maryland, south to Florida and the Keys, and west to Missouri and east Texas. Disjunct populations can be found north of their range in southern Iowa, Illinois, and southeast Nebraska. Eastern Narrow-mouthed Toads have been introduced on the banks of the Little and Great Bahama, and on the Cayman Islands.
Habitat and Feeding
These small frogs can inhabit a wide range of environments but require ample moisture and shelter, often living near bodies of water. They can be found under logs, boards, vegetative debris, and usually burrow into softer ground. This species can adapt to urban environments so long as the requirements are met. Their diet consists mostly of ants but have also been observed feeding on other insects such as termites and small beetles. A benefit of their small pointed snout is the ability to successfully forage for ants directly at the mound and the fold of skin on the back of their head can be moved forward to keep any insects from attacking the eyes.
Breeding and Reproduction
The breeding season commences with rains and occurs from March to October, but is restricted to the summer months in the northern part of the range. Males can be heard calling the most on rainy nights and usually stay sheltered within clumps of plants or grasses with their bodies floating free and forearms resting on debris. The advertisement call is a bleating sound, similar to that of a sheep or goat, and lasts anywhere from 1-4 seconds. The short nasal-y call has small pulses that are not easily heard, but can be seen well in the call structure. They utilize both temporary and permanent bodies of water but do best in shallow, fishless, temporary ponds. Females lay their eggs as a film on the surface of the water and tadpoles can metamorphose in 20-70 days.
Conservation
The Eastern Narrow-mouthed Toad is common throughout most of its range but declines have been reported in east Texas, likely a result of habitat loss. This species is not under federal protection but is included in the Texas Parks and Wildlife Black List.
Pertinent References
Makowsky, R., Chesser, J., and Rissler, L. J. 2009. A striking lack of genetic diversity across the wide-ranging amphibian Gastrophryne carolinensis (Anura: Microhylidae). Genetica 135:169-183.
McAllister, C. T., and Bursey, C. R. 2005. Endoparasites of the eastern narrowmouth toad, Gastrophryne carolinensis (Anura: Microhylidae), from northwestern Louisiana and northeastern Texas, U.S.A. Comparative Parasitology 72:124-128.
Mitchell, J. C., and Lannoo, M. J. 2005. Eastern Narrow-mouthed Toad. Pp. 501-503 in M. J. Lannoo (Ed.), Amphibian Declines: The Conservation Status of United States Species. University of California Press, USA.
Saenz, D., Fitzgerald, L.A., Baum, K.A., and Conner, R.N. 2006. Abiotic Correlates of Anuran Calling Phenology: The Importance of Rain, Temperature, and Season. Herpetological Monographs 20:64-82.
Account Author: Hailey Hester
Photos: James Childress
Edited by Christopher Schalk
