Typhlatya iliffei Hart & Manning, 1981
Typhlatya iliffei: after Hart & Manning, 1981
Taxonomic Characterization: The rostrum is simple and spine-like and the carapace is smooth and without spines. The telson is 4 times as long as it is wide with 5 pairs of spines and 2 pairs of setae on the posterior margin.
The lateral ramus of the uropod has a single blunt spine at the lateral angle. The caridean lobe on the first maxilliped is small but distinct. The eyes are pigmented and directed upward through the orbit. The antennal scale is less than
twice as long as it is wide with a gently curving outer margin. The walking legs are long and slender. The color overall is whitish with red chromatophores on the antennular and antennal peduncles (Hart & Manning, 1981).
Disposition of Specimens: Female holotype collected from Tucker's Town Cave deposited in the United States National Museum (USNM 184012); female paratype collected from the same location (USNM 184013).
Ecological Classification: Stygobitic
Size: Female holotype carapace length 6.5 mm, female paratype carapace length 6.3 mm.
Number of Species in Genus: Seventeen, all stygobitic.
Species Range: Known only from Tucker's Town Cave, Bermuda (Hart & Manning, 1981).
Closest Related Species: T. iliffei appears to be the most similar to T. rogersi due to their long rostrum and pigmented eyes. T. iliffei along with T. rogersi, T. galapagensis and T. garciai are the only four species of the genus that inhabit brackish water.
Habitat: Anchialine limestone caves
Ecology: T. iliffei inhabits Tucker's Town Cave, a single room cave with a sand and silt bottomed sea level pool in which the specimens were collected at a depth of 12 m. The pool's tidal fluctuations indicate a connection with the sea and the room has some illumination from light entering from above.
Life History: Two female specimens were collected.
Evolutionary Origins: Of the seventeen species in the genus, six (from the Galapagos Islands, Bahamas, Bermuda, Ascension Island, Yucatan and the Caicos Islands) inhabit brackish or marine waters, while the remainder are found in freshwater habitats. According to Iliffe (1986:7), "species within the genus appear to have evolved from an open water marine ancestor in the Atlantic which spread westward through the Caribbean into the Pacific with prevailing currents before the closure of the Panama land bridge." Iliffe et al. (1983) suggested an origin of the genus on submerged and emergent sea mounts associated with the Mid-Atlantic Ridge during the separation of the American and African continental masses.
Sanz and Platvoet (1995) believe that the occurrence of the genus in Europe links the origin of the genus Typhlatya to the Tethys Sea. The ancestor was probably a marine, coastal shrimp inhabiting low latitude seas. Maximal development of the ancestral range probably occurred in the Late Cretaceous (about 90 MYA). The full opening of the Atlantic and the end of global Tethyan currents divided its range into three populations: European, Mid-Atlantic Ridge and Central American. Central American populations were further subdivided by plate tectonics into Yucatan, Antilles and Galapagos populations. For unknown reasons, the ancestral marine populations disappeared, leaving only those species that had earlier entered the cave environment. Absence of clear morphological patterns within the recent species may be due to the early timing of isolation between and within lineages.
Conservation Status: T. iliffei is considered to be critically endangered (IUCN, 2000). It is restricted to a single anchialine cave in Bermuda.
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