Lepidophthalmus manningi, a new ghost shrimp from the southwestern Gulf ofMexico (Decapoda : Thalassinidea : Callianassidae)

Lepidophthalmus manningi, new species, is described from intertidal and sha llow subtidal margins of estuarine embayments, ephemeral tidal ponds, and r iver mouths in the states of Veracruz, Tabasco and Campeche, eastern Mexico . This apparent endemic of the southwestern Gulf of Mexico is ornamented by conspicuous sclerotized plates on ventral surfaces of the abdomen, a featu re it shares with several other tropically distributed species in the weste rn Atlantic and eastern Pacific, Lepidophthalmus manningi is very close in morphology to the recently described L. richardi from Belize, its apparent sibling, but can be distinguished by unique features in sculpture and shape of not only the ventral abdominal plating, but also in structures such as the rye tubercles, major chelipeds, and the anterior two pleopod pairs, dor sal abdominal tergites, and the uropods. It is readily distinguishable from two other Gulf of Mexico species, both of which lack ventral sclerotized p lates on the abdomen. The latter include the widely distributed warm-temper ate species, L. louisianensis, which ranges throughout the northern Gulf of Mexico and into Tamaulipas, Mexico, and a second southwestern Gulf endemic form that remains undescribed and is currently under study. Disjuncture of appropriate habitats in the northern Yucatan Peninsula and Limited dispers al ability in the genus appear to account for isolation of L. manningi from its Caribbean sibling.