Amsterdam Expeditions to the West Indian Islands, report 12. Some new hypogean cirolanid isopod crustaceans from Haiti and Mayaguana (Bahamas)

A new stygobiont genus of Isopoda Cirolanidae, Haitilana, with two new species, H. radicicola and H. acanthura, are described from groundwaters in Haiti. These are the first hypogean cirolanids recorded from the island of Hispaniola. The new genus is mainly characterized by its pleon segmentation, the clearly prehensile first pereiopods and weakly prehensile second and third pereiopods, and the 2- and 5- segmented pedunculus of antennae 1 and 2, respectively. Haitilana shows the greatest morphological resemblance to Antrolana lira Bowman, 1964, from the Appalachian Valley, Virginia, U.S.A. The localities where Haitilana was found, have been flooded by the sea during the Cenozoic. Regression seems to be the most plausible explanation for the evolution of Haitilana. Another new stygobiont cirolanid, Bahalana cardiopus, is described from a cave on Mayaguana, an island of the Bahamas. This species is congeneric with Bahalana geracei Carpenter, 1981, from the island of San Salvador (Bahamas). Clearly distinctive of B. cardiopus are the unarmed endopodites of pleopods 3 to 5, and the armature of the maxillipedal endite. The Bahama archipelago is an accumulation area. Bahalana has been found in meso- and polyhaline waters. Dispersal (from marine ancestors) seems to be the most plausible explanation for the evolution of Bahalana.