Eastern Narrow-Mouthed Toads: Dark Fat Body, Pointed Snout, Short Legs

Summary: North American eastern narrow-mouthed toad habitats get dark-and-pale-marked fat bodies with pointed snouts, speckled heads, small round-pupiled eyes, webless toes and single-spaded hindlimbs.

eastern narrow-mouthed toad (Gastrophryne carolinensis), with fold behind eyes apparent; Florida Panhandle: Jeromi Hefner/USGS National Wetlands Research Center (now USGS Wetland and Aquatic Research Center), Public Domain, via USGS Amphibian Research and Monitoring Initiative (ARMI)

North American eastern narrow-mouthed habitats adopt lower midwestern and southeastern distribution ranges in the United States from Maryland southward and westward through Florida, Texas, Oklahoma, Missouri, Kentucky and Virginia and everywhere in-between.

Eastern narrow-mouthed toads bear their common name for eastern biogeographies; ant-, beetle- and termite-eating adaptations; and Microhylidae arboreal, burrowing and terrestrial frog and toad family membership. The scientific name Gastrophryne carolinensis combines the Greek words γαστήρ (gastēr, "belly," "stomach") and φρύνη (phrunē, "toad") and the Latin carolinensis ([specimen collected in South] Carolina). Taxonomic designations derive from scientific descriptions in 1835 by John Edwards Holbrook (Dec. 31, 1796-Sep. 8, 1871) of bark- and fence-loving specimens from Charleston, South Carolina.

Eastern narrow-mouthed toad life cycles expect bottomland forests; coastal dune scrublands; debris-scattered, grass-clumped and log-strewn hideaways; permanent and temporary pools with floating vegetation, pinewoods and prairies.

March through October fit breeding months into eastern narrow-mouthed toad life cycles despite predatory copperheads, cottonmouths, fish, garter snakes, glossy watersnakes, grackles, raccoons and water bugs.

Eastern narrow-mouthed toads go on large sticky toe pads and long legs from bushes, shrubs and trees to breeding bayous, ditches, lakes, ponds, pools and swamps. Matched filtering helps them hear, despite mixed-species choruses, by calls having frequency ranges that vibrate two circular tympanic-membraned eardrums and the inner-ear's amphibian and basilar papillae. Closed-mouth, closed-nostril advertisement, similar courtship and rain and similar aggression and release calls impel air streams from lung expirations over vocal cords and inflate vocal sacs.

Batrachochytrium dendrobatidis fungus, fertilizer runoff, globally warmed climate change, non-native species, toxic pesticides, trematode fluke-induced deformities and ultraviolet radiation jeopardize North American eastern narrow-mouthed toad habitats.

Three hundred to 4,000-egg clusters and, four to 14 days later, gill-breathing, keel-tailed tadpoles keep to water whereas legged, lung-breathing, tailless adults know land and water.

Eastern narrow-mouthed toads look like 0.17- to 0.22-inch (4.5- to 5.5-millimeter), herbivorous (plant-eating) fish and little-legged, long-tailed, 2.36-plus-inch (60-plus-millimeter) carnivores (flesh-eaters) 25 to 45 days later. The male manages axillary amplexus (armpit embrace) by maintaining forelimbs behind his mate's front legs while mounted on her back to fertilize dark, sticky eggs externally. Tadpoles need algae, organic debris, plant tissue and suspended matter even though beetles, caterpillars, crickets, flies, mosquitoes, moths, pillbugs, sowbugs, spiders, stinkbugs and worms nourish adults.

North American eastern narrow-mouthed toad habitats offer season-coldest temperatures, northward to southward, from minus 5 to 25 degrees Fahrenheit (minus 20.55 to minus 3.88 degrees Celsius).

Bay laurel-, cypress- and emergent, floating, submerged, waterside grassy, herbaceous, weedy plant-dominated artificial and natural ditches, lakes, marshes, ponds, sloughs and swamps promote eastern narrow-mouthed toads.

Lang Elliott, Carl Gerhardt and Carlos Davidson quantify 0.875- to 2.5-inch (2.22- to 3.81-centimeter) snout-vent (excrementary opening) lengths in The Frogs and Toads of North America. Fat-bodied, fat-legged adults reveal pointed heads; gray- or red-brown upper surfaces with one dark center between two light bands; mottled abdomens; and white-speckled dark lower sides. Soft peeps and squeaks sound before or subsequent to bleating, buzzy, lamb-like, 1- to 3-second waaaaaaaaa! advertisement calls whereas harsh, slow, throaty brrrrrrrr calls signal aggression.

North American eastern narrow-mouthed toad habitats tender bleating, chunky, fat-legged, brown-gray-red-brown bodies with skin folds behind heads, mottled abdomens, black-marked, light-banded backs and white-specked dark sides.

eastern narrow-mouthed toad (Gastrophryne carolinensis) under synonym Engystoma carolinense; illustration by Italian-born scientific illustrator J. Sera, lithograph by George Lehman/Lehman & Duval Lithographers; J.E. Holbrook's North American Herpetology (1836), vol. I, Plate XI, opposite page 83: Public Domain via Biodiversity Heritage Library

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

eastern narrow-mouthed toad (Gastrophryne carolinensis), with fold behind eyes apparent; Florida Panhandle: Jeromi Hefner/USGS National Wetlands Research Center (now USGS Wetland and Aquatic Research Center), Public Domain, via USGS Amphibian Research and Monitoring Initiative (ARMI) @ https://armi.usgs.gov/gallery/result.php?search=Gastrophryne+carolinensis

eastern narrow-mouthed toad (Gastrophryne carolinensis) under synonym Engystoma carolinense; illustration by Italian-born scientific illustrator J. Sera, lithograph by George Lehman/Lehman & Duval Lithographers; J.E. Holbrook's North American Herpetology (1836), vol. I, Plate XI, opposite page 83: Public Domain via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/35765108; Biodiversity Heritage Library (BioDivLibrary), Public Domain, via Flickr @ https://www.flickr.com/photos/61021753@N02/6046608136/

For further information:

Elliott, Lang; Carl Gerhardt; and Carlos Davidson. 2009. The Frogs and Toads of North America: A Comprehensive Guide to Their Identification, Behavior and Calls. Boston MA; New York NY: Houghton Mifflin Harcourt.

Frost, Darrel. "Gastrophryne carolinensis (Holbrook, 1836)." American Museum of Natural History > Our Research > Vertebrate Zoology > Herpetology > Amphibian Species of the World Database.
Available @ http://research.amnh.org/vz/herpetology/amphibia/index.php//Amphibia/Anura/Microhylidae/Gastrophryninae/Gastrophryne/Gastrophryne-carolinensis

Holbrook, John Edwards, M.D. 1836. "Engystoma carolinense." North American Herpetology; Or, A Description of the Reptiles Inhabiting the United States. Vol. I: 83-84. Philadelphia PA: J. Dobson.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/4075426

"The 2012 USDA Plant Hardiness Zone Map." The National Gardening Association > Gardening Tools > Learning Library USDA Hardiness Zone > USDA Plant Hardiness Zone Map.
Available @ https://garden.org/nga/zipzone/2012/