Bahadzia stocki

Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Order Amphipoda
Family Hadziidae

Bahadzia stocki Holsinger, 1985

Taxonomic Characterization: Amphipod lacking eyes and pigment. B. stocki can be distinguished from other Bahadzia by the following characteristics by:

The lobe of merus of the first gnathopod is not distally produced.
The coxal gills are large.
The female's carpus of the second gnathopod is greater than or equal to the propodus, the palm of the second gnathopod is not strongly oblique, and the posterior margin of the propodus has four groups of setae.
The third maxillipedal palp segment is only slightly widened distally.
The third mandible palp segment has A-setae.
The peduncle of uropod one does not have a proximoventral spine.
The distal end of the peduncle of uropod 2 has five long spines, but does have a comb row of five smaller spines.

A key to the genus is presented in Jaume & Wagner, 1998.

Disposition of Specimens: National Museum of Natural History, Smithsonian Institution; and in the private collection of John Holsinger.

Ecological Classification: Stygobitic

Size: The females' length ranges from 5.0 to 6.5 mm. The male's length was 5.0 mm.

Number of Species in Genus: Nine (8 anchialine and 1 freshwater), all stygobitic

Bahamas:
- Cat Island: B. obliqua Stock, 1986
- Grand Bahama: B. williamsi Holsinger, 1985
- Abaco: B. williamsi Holsinger, 1985
- South Andros: B. setimana Stock, 1986
Caicos Islands:
- Providenciales: B. stocki Holsinger, 1985
Cuba: B. yagerae Ortiz & Perez, 1995
Dominican Republic: B. jaraguensis Jaume & Wagner, 1998
Haiti: B. latipalpus Stock, 1985
Mexico:
- Isla Cozumel: B. bozanici Holsinger, 1992 and B. setodactylus Holsinger, 1992
- Yucatan Peninsula: B. bozanici Holsinger, 1992

Genus range for Bahadzia

Species Range: Known only from Airport Cave and The Hole, Providenciales, Turks and Caicos Islands.

Closest Related Species: B. sentimana. The genus Bahadzia is restricted to the West Indies and Mexico. All species are closely related, and it is unclear if they are distinct species or are subspecies (Stock, 1986). The only freshwater species, B. latipalpus, has the most distinct morphology, while the anchialine species more closely resemble each other.

Habitat: Anchialine limestone cave.

Ecology: Collected from the bottom of polyhaline waters (18 ppt), at a depth of 12 to 18 m. The oxygen concentration at this depth is very low, less than 1 ppm.

Life History: All females had setose brood plates and appeared sexually mature. Amphipods do not have larvae or resting stages. These attributes affect their dispersal capacities and thus, contribute to their endemism.

Evolutionary Origins: The genus Bahadzia is phylogenetically with Mayaweckelia and Tuluweckelia. "It may be an ancient relict derived from an early hadziid fauna in the old Tethyan seaway" (Holsinger et al., 1986).

Conservation Status: Restricted to two caves on the island Providenciales.

References:

Holsinger, J.R. 1992. Two new species of the subterranean amphipod genus Bahadzia (Hadziidae) from the Yucatan Peninsula region of southern Mexico, with an analysis of phylogeny and biogeography. Stygologia, 7:85-105.
Holsinger, J.R., D. Williams, J. Yager, and T.M. Iliffe. 1986. Zoogeographic implications of Bahadzia, a hadziid amphipod crustacean recently described from anchialine caves in the Bahamas and Turks and Caicos Islands. Stygologia, 2:77-83.
Holsinger, J.R. and J. Yager. 1985. A new genus and two new species of subterranean amphipod crustaceans (Hadziidae) from the Bahamas and Turks and Caicos Islands. Bijdragen tot de Dierkunde, 55 (2):283-294.
Jaume, D. and H.P. Wagner. 1998. New cave-dwelling amphipods (Lysianassidae, Hadziidae) from the Dominican Republic (Hispaniola). Contributions to Zoology, 68(1):37-66 19 figures.
Ortíz, M.R. and A. Pérez. 1995. Una nueva especie de anfipodo cavernícola hadzioideo (Amphipoda, Gammaridea) de Cuba. Graellsia, 51:165-168.
Stock, J.H. 1985. Stygobiont amphipod crustaceans of the Hadzioid group form Haiti. Bijdragen tot de Dierkunde, 55:331-426.
Stock, J.H. 1986. Two new amphipod crustaceans of the genus Bahadzia from 'blue holes' in the Bahamas and some remarks on the origin of the insular stygofaunas of the Atlantic. Journal of Natural History, 20:921-933, 5 figures.