A New Species of Freshwater Prawn, Macrobrachium Totonacum (decapoda, Palaemonidae), with Abbreviated Development from Mexico

A new species of the genus Macrobrachium from northern Oaxaca, Mexico, with abbreviated larval development, is described. Macrobrachium totonacum new species, is similar to M. tuxtlaense and M. vicconi in exhibiting abbreviated larval development, but differs from these in the length of the e rst pereiopod and relative proportions of the articles of the second pereiopod. Macrobrachium totonacum occurs in the San Antonio River, which originates in the Cueva del Nacimiento del Ri o San Antonio where the troglobyte M. villalobosi is found. However, both species differ in pigmentation, the number of rostral spines, proportions of the scaphocerite, relative proportions of the carpus and propodus of the e rst pereiopod, and the carpus, merus, and propodus of the second pereiopod.