Anchialocarididae, a new family of anchialine decapods and a new species of the genus Agostocaris from Cozumel Island, Mexico

Abstract

Two new species of anchialine cave shrimp from Cozumel Island are described. A new species from the family Agostocarididae, Agostocaris zabaletai n. sp., occurs in three cenotes on the island (Chempita, Chankanaab System and Tres Potrillos). This new species is closely related to Agostocaris bozanici that is known from one isolated cenote in another zone of the island. Agostocaris zabaletai n. sp. is similar to A. bozanici because it lacks a rostrum with teeth, and the palp of the first maxilliped is not segmented. In addition A. zabaletai also differs from A. bozanici by bearing four pairs of spines on the telson and only one spine on the outer ramus of the uropods. Both Agostocaris williamsi and Agostocaris acklinsensis differ from A. zabaletai because both species have occasionally a serrate rostrum, and these species are reported exclusively from the Bahamas. A new family, Anchialocarididae, new genus and species Anchialocaris paulini n. sp. are described. This new species is known exclusively from the cenote Chempita located in the central area of the island. The new family Anchialocarididae is closely related to the families Agostocarididae and Atyidae because they have a similar branchial formulae. The main difference is that the new family has a simple articulation between carpus and palm of the first pereiopod, and this appendage is more slender than the second. Although the new family has several setae on the rudimentary propodus on the second pereiopod it lacks the abundance of setae found in other members of the Atyidae family genus Typhlatya. The relationship between this new family and the Agostocarididae is discussed.