Stygiomysis holthuisi

Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Order Mysidacea
Family Stygiomysidae

Stygiomysis holthuisi (Gordon, 1958)

Taxonomic Characterization: The genus Stygiomysis includes blind, stygobitic mysids characterized by a rather vermiform body, a reduced carapace, endopods of thoracopods 2-4 prehensile, and protopod of uropod produced into a long distomedial process. Stygiomysis females have four pairs of developing oostegites, a number unique among the Mysidacea.

Ecological Classification: Stygobitic

Size: Up to 10 mm in length.

Number of Species in Genus: Six described species, all anchialine stygobitic

Genus Range:

Anguilla: S. holthuisi (Gordon, 1958)
Bahamas:
- Grand Bahama Island: S. holthuisi (Gordon, 1958)
Caicos Islands:
- Middle Caicos Island: S. clarkei Bowman, Iliffe, & Yager, 1984
- Providenciales Island: S. clarkei Bowman, Iliffe, & Yager, 1984
Dominican Republic: S. aemete Wagner 1992
Southern Italy: S. hydruntina Caroli, 1937
Jamaica: S. major Bowman, 1976
Mexico:
- Yucatan Peninsula: S. cokei Kallmeyer & Carpenter, 1996 and S. holthuisi (Gordon, 1958)
Puerto Rico: S. holthuisi (Gordon, 1958)
St. Martin: S. holthuisi (Gordon, 1958)
United States:
- Florida: S. sp. Bowman, in litt.

Species Range: Grand Bahama Island, Bahamas (Lucayan Caverns), Puerto Rico (Cueva de los Murcelagos, Guanica Fores), Anguilla (Salt Well, The Fountain), St. Martin (Devil's Hole) and Yucatan Peninsula, Mexico (Mayan Blue, Casa Cenote and Cenote Mucuyché).

Closest Related Species:

Habitat: Anchialine limestone caves

Ecology: This species was observed crawling on a rock at a depth of 4 m in a freshwater passage.

Evolutionary Origins: According to Pesce (Groundwater Mysids of Italy), "The remarkable distribution of Stygiomysis undoubtedly points to a Tethyan origin, all the species of this genus being actually known from the Caribbean area and South Italy."

Conservation Status: Restricted to anchialine caves

Reference:

Botosaneanu, L. 1980. Stygiomysis holthuisi found on Anguilla (Crustacea, Mysidacea). Studies on the fauna of Curacao and other Caribbean Islands, 61(190):128-132.
Bowman, T.E. 1976. Stygiomysis major, a new troglobitic mysid from Jamaica, and an entension of the range of S. holthuisi to Puerto Rico (Crustacea: Mysidacea: Stygiomysidae). International Journal of Speleology, 8:365-373.
Bowman, T.E. 1986. Mysidacea. In: Lazare Botosaneanu, editor, Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters. Pages 405-409. Leiden: E.J. Brill/Dr. W. Backhuys.
Bowman, T.E., T.M. Iliffe, and J. Yager. 1984. New records of the troglobitic mysid genus Stygiomysis: S. clarkei, new species, from the Caicos Islands, and S. holthuisi (Gordon) from Grand Bahama Island (Crustacea: Mysidacea). Proceedings of the Biological Society of Washington, 97(3):637-644, 4 figures.
Gordon, I. 1958. A new subterranean crustacean from the West Indies. Nature, 181:1552-1553.
Gordon, Isabella. 1960. On Stygiomysis from the West Indies, with a note on Spelaeogriphus (Crustacea, Peracarida). Bulletin of the British Museum (Natural History), Zoology, 6(5):285-324.
Pesce, G.L. and T.M. Iliffe. 2002. New records of cave-dwelling mysids from the Bahamas and Mexico with description of Palaumysis bahamensis n. sp. (Crustacea: Mysidacea). Journal of Natural History, 36(3):265-278, 21 figures.
Pesce, G.L., L. Juberthie-Jupeau and F. Passelaigue. 1994. Mysidacea. Encyclopaedia Biospeologica. Societè de Biospéologie, Moulis, Bucarest: 113-119, 4 figures.