Stygiomysis clarkei Bowman, Iliffe and Yager, 1984

Pesce, Giuseppe L. & Iliffe, Thomas M., 2002, New records of cave-dwelling mysids from the Bahamas and Mexico with description of Palaumysis bahamensis n. sp. (Crustacea: Mysidacea), Journal of Natural History 36 (3), pp. 265-278 : 270

Stygiomysis clarkei Bowman, Iliffe and Yager, 1984

Material examined. Grand Bahama Island, Bahamas: Lucayan Caverns , Freeport; 6 August 1998, one aberrant (female?) specimen collected with vial from the water column in 5-10 m depths. Lucayan Caverns , Freeport; 18 August 1998, one immature specimen (female?) collected with vial from the water column in 5-10 m depths. Lucayan Caverns , Freeport; 20 August 1998; one female (5.5 mm) collected with vials from the water column in 5-10 m depths. Lucayan Caverns , Freeport; 22 August 1998; two females (5.9, 6.1 mm) collected with vials from the water column in 5-10 m depths .

Remarks. The three adult specimens from Lucayan Caverns, Grand Bahama fi t the original description of the species, except for the following minor differences, which, in our opinion, could better characterize the Lucayan population rather than justify the proposition of a new species or subspecies.

(1) Distal armature of telson: 3+ 4+ 3+ 4+ 3, or 3+ 3+ 3+ 3+ 3 (vs 3+ 3+ 3+ 3+ 3 in the original description).

(2) Protopodal process of uropods with one lateral apical seta and fi ve apical spines, followed by two short spines, one longer spine and eight short setules (vs one lateral apical seta, fi ve apical spines followed by four short spines, one long spine and six to eight spinules, in the original description).

(3) Antenna 1, outer fl agellum 14- or 15-segmented (vs 17-19 in the original description), inner fl agellum nine-segmented (vs ten-segmented in the original description).

Stygiomysis clarkei is presently known only from anchialine caves in Middle Caicos, Providenciales and Grand Bahama islands (present data).

Habitat. Lucayan Caverns is located about 20 km east of Freeport on Grand Bahama Island. It is the longest explored cave in the Bahamas with more than 10 km of surveyed underwater passages. The surface waters in the cave are fresh, with a halocline at 16 m depth and full strength sea water beneath. Most passages were formed at the same depth as the halocline by mixing corrosion between fresh and salt waters. An unusual feature of this cave is the presence of large amounts of fl occulent organic sediments, probably of bacterial origin, that occur below the halocline.