Order Bochusacea (Mictacea partim)
Thetispelecaris remex Gutu & Iliffe, 1998
Thetispelecaris remex: whole animal, after Gutu & Iliffe, 1998
Taxonomic Characterization: Cylindrical body. Cephalon fused with one
thoracic somite. Pereon formed of seven free pereonites. Pleon with six
pleonites. Telson free. Eye lobes absent. Antennule with three-segmented
peduncle and two flagella. Antenna with squama. Mouthparts, completely
uncovered, large sized, with numerous long setae. Distinguished from other
members of family Hirsutiidae by pereopod I with exopodite. Also, labium (paragnaths)
with palpiform rostral prolongation distally covered with long hairs. (View
Scanning Electron Micrographs of T. remex)
Ecological Classification: Stygobitic
Size: Females' length range from 1.2 to 1.6 mm.
Number of Species in Genus: Two
|Thetispelecaris: genus range|
Species Range: Norman's Pond Cave, Norman's Pond Cay; Mystery Cave,
Stocking Island; and Master Harbour Cave, Great Exuma Island, all within the
Exuma Cays, Great Bahama Bank, Bahamas
Closest Related Species: T. remex is most closely related to the only other species in the genus, T. yurikago from Grand Cayman Island. Thetispelecaris is a sister genus of Hirsutia, which consists of deep-sea species from the Tasmanian Sea and Atlantic Ocean.
Habitat: Anchialine and marine limestone caves
Ecology: Found in fully marine salinity water, at depths ranging from 6 to 50 m. They were collected from the ceiling, walls, silt ledges, and sandy floor of both inland anchialine caves and ocean blue holes.
Life History: The order Bochusacea is unique among the Peracarida. Most peracaridan females have a marsupium formed of oostegites (temporary structures) which are developed on adults only in the reproductive period. In Bochusacea, the epipodites (permanent structures) probably have the temporary role of sustaining the eggs without forming a marsupium. However, pereopod I is functional, morphologically similar to a maxilliped, and can be considered maxilliped II. 16 females and 5 manca were collected. The males of this species are unknown. The manca stage is characterized by absence of the last pair of pereopods and epipodites, while the pleopods are present. Manca range in size from 0.80 to 0.95 mm.
Evolutionary Origins: The presence of the epipodites in females, which may play the role of oostegites, indicate that this may be the most primitive order of Peracarida, bordering the superorder Syncarida. It is questionable that Bochusacea are actually Peracarida (Sanders, Hessler & Garner, 1985:55; Gutu & Iliffe, 1998:98; Gutu, 1998:121; Hessler, 1999:90).
Conservation Status: Restricted to three caves within the Exuma Cays.
Contributor: Modest Gutu, Grigore Antipa National Museum of Natural
History, Bucharest, Romania