Stenobermuda mergens

Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Order Isopoda
Family Gnathostenetriodidae

Stenobermuda mergens Botosaneanu & Iliffe, 1999

Taxonomic Characterization: A stygobitic asellot isopod without eyes (ommatidia) and completely depigmented. Ratio of body length/maximum width slightly exceeding 3.5. Distal margin of cephalon with triangular, not very acute, rostrum. Longest pereionites are II and III. Two very small pleonites. Pleotelson relatively broad (Botosaneanu & Iliffe, 1999).

Disposition of Specimen: Zoölogisch Museum, Amsterdam.

Ecological Classification: Stygobitic
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Size: male holotype body length 3.2 mm.

Number of Species in Genus: Four, two of which are stygobitic (S. mergens and S. iliffei).

Genus Range:

Bahamas
- Andros Island: S. mergens Botosaneanu & Iliffe, 1999
  - Conch Sound Blue Hole
Bermuda: S. acutirostrata Schultz, 1978; S. iliffei Kensley, 1994
Caicos Islands: S. acutirostrata Schultz, 1978 reported in Schotte, Heard & Kensley, 1991
South Africa: S. syzygus (Barnard, 1940)

Species Range: Known only from Conch Sound Blue Hole, Andros Island, Bahamas.

Closest Related Species: S. mergens, S. acutirostrata and S. iliffei are closely related species.

Habitat: Ocean blue hole limestone cave

Ecology: Collected by diving with a plankton net from 26 m depth, 750 m penetration inside this ocean blue hole (Botosaneanu and Iliffe, 1999).

Life History: Only a single male specimen has been collected from from Conch Sound Blue Hole, Andros Island.

Evolutionary Origins: S. mergens and S. iliffei are hypogean offshoots of S. acutirostrata, a shallow water marine species widely distributed in the Western Atlantic. Possibly other subterranean adapted species will be discovered in hypogean habitats inside the distribution area of the marine species. Colonization of subterranean aquatic habitats by shallow water marine elements in Gnathostenetroidoidea and Stenetrioidea is considered as being a general phenomena (Wägele, 1990).

Conservation Status: Restricted to a single blue hole cave on Andros Island; known only from a single specimen.

References:

Botosaneanu, L. and T.M. Iliffe 1999. A simple scenario for stygobitization in Stenobermuda Schultz, 1978 (Isopoda Asellota Stenetriidae), with description of a new species from Andros Island. International Journal of Speleology, 26:37-45, 9 figures.
Schotte, M., R.W. Heard and B. Kensley. 1991. Studies of the Crustacea of the Turks and Caicos Islands, British West Indies. III. Records of marine Isopoda for Pine Cay, Fort George Cay, Water Cay, and adjacent waters. Gulf Reseach Reports, 8(3):251-257.
Schultz, G.A. 1978. A new Asellota (Stenetriidae) and two, one new, Anthuridea (Anthuridae) from Bermuda (Crustacea: Isopoda: Asellota). Proceedings of the Biological Society of Washington 91(4):904-911.
Serov, J.H. and R. Vonk. 1990. A review of the Stenetriidae (Crustacea: Isopoda: Asellota). Records of the Australian Museum 47:39-82.
Wägele, J.W. 1990. Aspects of the evolution and biogeography of stygobiontic Isopoda. Bijdragen tot de Dierkunde, 60(3/4):145-150.