The Alabama cave shrimp (''Palaemonias alabamae'') is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

shrimp A shrimp (: shrimp (American English, US) or shrimps (British English, UK)) is a crustacean with an elongated body and a primarily Aquatic locomotion, swimming mode of locomotion – typically Decapods belonging to the Caridea or Dendrobranchi ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Atyidae Atyidae is a family of shrimp, present in all tropical and most temperate waters of the world. Adults of this family are almost always confined to fresh water Fresh water or freshwater is any naturally occurring liquid or frozen water conta ...

, found only in caves in the state of

Alabama Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gu ...

Conservation status

''Palaemonias alabamae'' is listed as an

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

both on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

, and since September 7, 1988, under the U.S.

Endangered Species Act The Endangered Species Act of 1973 (ESA; 16 U.S.C. § 1531 et seq.) is the primary law in the United States for protecting and conserving imperiled species. Designed to protect critically imperiled species from extinction as a "consequence of e ...

Distribution

The Alabama cave shrimp is only known from five

cave Caves or caverns are natural voids under the Earth's Planetary surface, surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend a relatively short distance undergrou ...

s, all in Madison County,

Shelta Cave Shelta Cave is a cave and lake located in Huntsville, Madison County, Alabama, United States. It is described as one of the most bio-diverse caves within the Appalachian Mountains. The cave is currently owned and managed as a nature preserve by ...

is the species' type locality, but viable populations have only been confirmed in Bobcat Cave and the complex comprising Hering Cave, Glover Cave and Brazelton Cave.

Ecology

''P. alabamae'' occurs in cave pools with

silt Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension (chemistry), suspension with water. Silt usually ...

y bottoms. Predators of the Alabama cave shrimp include the southern cavefish '' Typhlichthys subterraneus'', the

Tennessee cave salamander The Tennessee cave salamander (''Gyrinophilus palleucus'') is a species of salamander in the family Plethodontidae, endemic to the Appalachian Mountains in the United States. Its natural habitats are streams in caves. It is threatened by habitat ...

Gyrinophilus palleucus The Tennessee cave salamander (''Gyrinophilus palleucus'') is a species of salamander in the family Plethodontidae, endemic to the Appalachian Mountains in the United States. Its natural habitats are streams in caves. It is threatened by habitat ...

'', various

crayfish Crayfish are freshwater crustaceans belonging to the infraorder Astacidea, which also contains lobsters. Taxonomically, they are members of the superfamilies Astacoidea and Parastacoidea. They breathe through feather-like gills. Some spe ...

species,

bullfrog ''Bullfrog'' is a common English language term to refer to large, aggressive frogs, regardless of species. Examples of bullfrogs include: Frog species Americas *Helmeted water toad (''Calyptocephalella gayi''), endemic to Chile *American bullf ...

s and

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the North American, northern or common raccoon (also spelled racoon) to distinguish it from Procyonina, other species of raccoon, is a mammal native to North America. It is the largest ...

Taxonomy

The closest relative of the Alabama cave shrimp is the Kentucky cave shrimp, ''Palaemonias ganteri'', which lives in

Mammoth Cave National Park Mammoth Cave National Park is a national park of the United States in south-central Kentucky. It encompasses portions of Mammoth Cave, the longest known cave system in the world. The park's are located primarily in Edmonson County, with sma ...

Kentucky Kentucky (, ), officially the Commonwealth of Kentucky, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the ...

. The two species can be distinguished by size (''P. alabamae'' being larger than ''P. ganteri''), the longer

rostrum Rostrum may refer to: * Any kind of a platform for a speaker: **dais **pulpit ** podium * Rostrum (anatomy), a beak, or anatomical structure resembling a beak, as in the mouthparts of many sucking insects * Rostrum (ship), a form of bow on naval ...

in ''P. alabamae'', and the greater number of spines on the rostrum of ''P. alabamae''.

References

{{Authority control Atyidae Endemic crustaceans of the United States Cave shrimp Endemic fauna of Alabama Freshwater crustaceans of North America Madison County, Alabama Crustaceans described in 1961 Endangered fauna of the United States ESA endangered species