Tulumella bahamensis

Phylum Arthropoda
Subphylum Crustacea
Class Eumalacostraca
Order Thermosbaenacea
Family Tulumellidae

Tulumella bahamensis Yager, 1987

Taxonomic Characterization: Eyes absent, eyestalks oval. Carapace covering pereonites 1-7. Pigmentation lacking. Antenna 1 short, less than half of body length. Antenna 2 exopod (scale) subrectangular with about 5 long plumose marginal setae. Left mandible with 3-cusped incisor process and 3 cusped lacinia mobilis, right mandible with 4-cusped incisor process. Maxilla 1 endopod apex with 3 short spoon-shaped spines and 4 naked setae. Maxilla 2 basal elements with modified spoon setae bearing thin filament on apex. Dactyl of pereopods 2-7 with very weakly serrate apex. Telson with 2 short apical spines flanked laterally by 1 long spine and 2 progressively shorter spines (Yager, 1987).

Ecological Classification: Stygobitic

Size: Length of adults from 3 to 3.5 mm

Number of Species in Genus: Three, all stygobitic

Genus Range:

Bahamas Abaco: T. bahamensis Yager, 1987 and T. grandis Yager, 1987 Andros: T. bahamensis Yager, 1987 and T. grandis Yager, 1987 Grand Bahama: T. bahamensis Yager, 1987 and T. grandis Yager, 1987 Yucatan Peninsula: T. unidens Bowman & Iliffe, 1988 Cenote Najaron (type locality); Cenote Temple of Doom, Cenote Carwash reported in Holsinger, 1990
		*Tulumella*: genus range

Species Range: Known from two caves (Lucayan Caverns, Mermaid's Lair) in Grand Bahama, one cave in Abaco (Dan's Cave) and two in South Andros (El Dorado Cave, Stargate Blue Hole).

Closest Related Species: Not known. T. bahamensis is distinct from both T. grandis and T. unidens.

Habitat: Anchialine, inland blue hole, limestone caves

Ecology: Tulumella bahamensis is a relatively euhaline neritic species that lives near the density interface of the halocline. In Lucayan Caverns, thermosbaenaceans are the most abundant animal in the water column, with as many as 20 individuals per cubic meter. They are typically found in association with a number of other stygobitic taxa including remipedes (Speleonectes, Cryptocorynetes, Godzillius, Pleomothra and Godzilliognomus), amphipods (Bahadzia and Spelaeonicippe), isopods (Bahalana), mysids (Stygiomysis), ostracods (Deeveya and Spelaeocia) and fish (Lucifuga). T. bahamensis occurs sympatrically with T. grandis in Lucayan Caverns, Dan's Cave and El Dorado Cave.

Life History: The 6 specimens reported by Yager (1987) were all females.

Evolutionary Origins: The distribution of thermosbaenaceans with hypogean species in the West Indies, Yucatan, Texas, the Canary Islands, the Mediterranean region, Somalia and Cambodia is taken to indicate a Tethyan origin associated with the breakup of Pangea in post-Jurassic time (Schram, 1986; Cals & Monod, 1988).

Conservation Status: Known from inland blue hole caves on both the Great Bahama and Little Bahama Banks.

References:

Cals, P. and T. Monod. 1988. Évolution et biogéographie des Crustace´s Thermosbénace´s. Comptes Rendus Hebdomadaires des Seances de l’Academie des Sciences, series 3, 307:341–348.
Schram, F. R., 1986: Crustacea. New York, Oxford: Oxford University Press.
Stock, J. H. 1986. Thermosbaenacea. In: Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the marine interstitial). L. Botosaneanu (ed.) Leiden, The Netherlands - E.J. Brill / Dr. W. Backhuys.
Wagner, H.P. 1994. A monographic review of the Thermosbaenacea (Crustacea: Peracarida): A study on their morphology, taxonomy, phylogeny and biogeography. Zoologische Verhandelingen (Leiden). 291:3-338.
Yager, J. 1987. Tulumella grandis and T. bahamensis, two new species of thermosbaenacean crustaceans (Monodellidae) from anchialine caves in the Bahamas. Stygologia, 3(4):373-382, 4 figures.