Vernacular Name AMPHIUMA, ONE-TOED (Aka: Congo Eel, Congo Snake, Ditch Eel, Fish Eel and Lamprey Eel)
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1/6 Vernacular Name AMPHIUMA, ONE-TOED (aka: Congo Eel, Congo Snake, Ditch Eel, Fish Eel and Lamprey Eel) GEOGRAPHIC RANGE Eastern Gulf coast. HABITAT Wetlands: slow moving or stagnant freshwater rivers/streams/creeks and bogs, marshes, swamps, fens and peat lands. CONSERVATION STATUS IUCN: Near Threatened (2016). Population Trend: Decreasing. Because of the limited extent of its occurrence and because of the declining extent and quality of its habitat, this species is close to qualifying for Vulnerable. COOL FACTS Amphiumas are commonly known as "Congo eels," a misnomer. First of all, amphiumas are amphibians, rather than fish (which eels are). This notwithstanding, amphiumas bear resemblance to the elongate fishes. It is easy to overlook the diminutive legs, and the lack of any external gills adds to the similarity between the amphiumas and eels. Amphiumas are adapted for digging and tunneling. They seem to spend most of the time in muddy burrows and are rarely observed in the wild. They never fully metamorphose and retain larval characteristics in varying degrees into adulthood: one pair of the larval gill slits is retained and never disappears, no eyelids, no tongue and the presence of 4 gill arches with a single respiratory opening between the 3 rd--4th arches. Amphiumas have two pairs of limbs, and the three species, all of which occur in the S.E. U.S, differ in regard to the number of toes at the ends of these limbs: one, two or three. These amphiumas possess tiny, single-toed limbs, one pair just behind the small gill opening at each side of the neck and another pair just ahead of the longitudinal anal slit . Because of its small size relative to other amphiumas and reduced number of toes, the one- Amphiuma, One-toed 2/6 toed amphiuma is considered a dwarf species Despite an aquatic lifestyle, they breathe air through their lungs by periodically poking the nostrils above the surface of the water. They can exist up to 3 years without food. Amphiuma cells, especially the red blood cells, are the largest known in vertebrates and have long been used in physiological studies and in the classroom. Its fossil history dates back 65 million years, almost to the time of the disappearance of the dinosaurs. DIET In wild: aquatic, mud-dwelling invertebrates, presumably small clams, earthworms, larval aquatic insects, small beetles, worms, crustaceans, crayfish, amphibian larvae and snails. In zoo: Notably lacking from the diet are dragonfly naiads, salamander larvae, frog tadpoles, and small fish that co-habit the same mucky sites . MEDIAN LIFE EXPECTANCY Unknown. ENEMIES - DEFENSE Enemies: turtles (common snapping, mud, musk), snakes (mud, red-bellied water, brown water, queen, ring-necked, and cottonmouths), frogs (southern leopard, bronze), 2-toed amphiumas, feral pigs, raccoons, large wading birds and humans. Defense: a noxious skin secretion, producing foam, which is bitter tasting and slightly numbing. MATING - CARE OF THE YOUNG Courtship and reproductive process: Not yet recorded. Adult males may fight during the reproductive season. Nest: the female builds a nest in a moist place under logs, leaves or other cover. Fertilization: internal through the direct transfer of the spermatophore from the male’s cloaca into the female’s cloaca. Gestation: up to 6 months. Egg laying: probably occurs in the summer (June, July). Clutch size: Usually 50-200 eggs laid in rosary-like strings with a constriction between each egg. Hatching: occurs late summer/early fall. Hatchlings: 2” long. May have thin, feathery gills and a short larval life for a few days before metamorphosing into air-breathing juveniles. Parental Care: females care for the eggs by coiling around the egg mass. Sexual Maturity: at about 1 year. Mating Frequency: females reproduce biennially; males reproduce annually. SOCIAL INTERACTION Out of the water, they may emit a whistling sound. Amphiuma, One-toed 3/6 LIFE STYLE Activity Period: nocturnal, retreating into burrows during the day. Feeding Habits: - they lie in wait for passing prey or prowl in search of prey . - strong teeth and a powerful bite assist in subduing prey. Locomotion: lateral undulations. Aquatic. - However, they are capable, though rare, of exiting the water and traveling short distances on land, especially on wet nights or when females are brooding eggs. - Although they tend to keep to the thick bottom-layer of muck, which is anaerobic, one- toed amphiumas must come to the surface to breathe. During dry periods and droughts, to avoid desiccation, they will burrow into the moist mud, at least 12” underground (have been found at 3’ depths), where they can reside until the next rain. They are adapted for digging and tunneling. Seasonal migrations: in winter they have occasionally been found under large logs buried along stream courses in first-order stream valleys where the species is not found in the spring, summer or fall, presumably to find protection from cold weather in warmer headwater seepages. PHYSICAL General Description: an elongate, cylindrical, eel-like salamander. - Body: Cylindrical and highly elongated. Diameter: Slightly more than the width of a pencil. - Lacks costal grooves (unlike the other 2 amphiumids). - Gills: No external gills in adults. Single gill slit on each side of the neck in pharyngeal region. Size: 8.5”-12.5” long. No sexual dimorphism in body size. Considerably smaller than the other 2 amphiuma species. Body Covering: skin is smooth and slippery. Exudes slippery mucus. Is shed periodically and may be eaten, thus helping to sustain the species. Color: dark reddish brown or gray to grayish brown; the belly is only slightly lighter than the top side. Head: flat, pointed. Conical, cylindrical. - Snout: rounded, not depressed. Sensory Organs. - Eyes: very small. Eyelids absent. Dentition: distinct crowns. Strong. Their bite can be painful. Limbs: highly reduced. 4 extremely tiny limbs (0.4”-0.7”) relative to the body size; almost vestigial. Each limb has 1 toe. Not of use in locomotion. Amphiuma, One-toed 4/6 Tail: laterally compressed. About 22%-25% of the total length. Lungs: present. Breathe air through their lungs by periodically poking the nostrils above the surface of the water. Lungs begin to work after about 4 months when the external gills disappear. Can also breathe through the pharynx and the skin. TAXONOMY Phylum / Subphylum Chordata / Vertebrata Class / Subclass Amphibia / Lisamphibia Order / Suborder Caudata (Urodela) / Salamandroidea Family Amphiumidae Genus / Species Amphiuma pholeter It is thought that the generic name comes from the Greek words “ amphi” (on both sides) and “pneuma” (breath). This may refer to the permanent gill openings on both sides of the body. REFERENCES - Banks, R. C., R. W. MacDiarmid, A. L. Gardner, and W. C. Starnes 2003. Checklist of Vertebrates of the United States, the U.S. Territories, and Canada. - Frost, Darrel R. 1997. Amphibian Species of the World, A Taxonomic and Geographic Reference. Second edition. New York, New York, U.S.A. - Hammerson, Geoffrey, Dale Jackson 2004. Amphiuma pholeter. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.1. www.iucnredlist.org - Hutchins, Michael, William E. Duellman and Neil Schlager, Editors. 2004. Grzimek’s Animal Life Encyclopedia. Vol. 6: Amphibians. Farmington Hills, MI. Gale Group. - Lannoo, Michael, ed: Amphibian Declines: The Conservation Status of United States Species , 2005. The Regents of the University of California), used with permission of University of California Press. - Means, D. Bruce. 2004. One-toed Amphiuma, Amphiuma pholeter Neill. In Ralph E. Mirarchi, ed. Vertebrate and Selected Invertebrate Wildlife of Alabama. - Mount, Robert H. 1975. The Reptiles and Amphibians of Alabama . The University of Alabama Press: Tuscaloosa, Alabama. - AmphibiaWeb: 2007. Berkeley, California: Amphibia Web. http://amphibiaweb.org/. - Frost, Darrell and The American Museum of Natural History. research.amnh.org/herpetology/amphibia/references.php?id=25257;1998-2007 - Georgia Museum of Natural History and Georgia Department of Natural Resources 1 June 2000; museum.nhm.uga.edu/gawildlife/amphibians/caudata/amphiumidae/apholeter.html - Larson, Allan. 1996. Amphiumidae. Amphiumas. Version 01 January 1996 (under construction). http://tolweb.org/Amphiumidae/15440/1996.01.01 in The Tree of Life Web Project, http://tolweb.org/ - Means, Bruce D. www.outdooralabama.com/watchable-wildlife/what/Amphibians/Salamanders/ota.cfm Amphiuma, One-toed 5/6 - Myers, P., R. Espinosa, C. S. Parr, T. Jones, G. S. Hammond, and T. A. Dewey. 2006. The Animal Diversity Web (online). http://animaldiversity.org. - National Zoo Fact Sheet: http://natzoo.si.edu/Animals/ReptilesAmphibians/Facts/FactSheets/Threetoedamphiuma.cfm - NatureServe. 2006. NatureServe Explorer: An online encyclopedia of life [web application]. Version 6.1. NatureServe, Arlington, Virginia. http://www.natureserve.org/explorer. - Salamanders of Georgia and South Carolina. Photos by J.D. Willson. www.uga.edu/srelherp/salamanders/amppho.htm - www.caudata.org/cc/species/Amphiuma/Amphiuma.shtml - The IUCN Red List of Threatened Species. Version 2016-1. <www.iucnredlist.org>. Downloaded on 02 July 2016. Prepared by: Judith Ehrman, docent Date: 04-01-07 Photo by: Lyn Tunmer, PZ Graphics Map by: Judy Ehrman – Bob Sloane, docents Approved by: Date: Reformatted by: Judith Ehrman and Bob Sloane, docents Date: 06-19-12 Amphiuma, One-toed 6/6 This page intentionally left blank .