TERRESTRIAL ISOPODS INCLUDED IN MIOCENE AMBER FROM CHIAPAS, MEXICO

The amber of Chiapas is famous for the quality and diversity of animal and plant taxa (even Fungi) preserved in this fossil resin. Flowers, leaves, pollen, gastropods, insects, and vertebrates have been documented from the Simojovel amber. The crustaceans are represented by terrestrial amphipods and one crab. Here we present terrestrial isopods, resented by seven specimens, preserved in two pieces of amber. The isopods are corpses that preserve important morphological features, such as compound eyes, mouth parts, antennae, antennulae, pleopods, uropods and telson. Presence of compound eyes, short antennulae, antennae with articulated peduncles (five to our segments), pereiopod coxae one to seven distinct and expanded, and reduced endite of uroods, suggests that the specimens belong to the genus Armadilliniscus (Family Oniscidae). This is the first report for fossil terrestrial isopods from Mexico, and expands the long systematic list of taxa included in the amber of Chiapas. Evidence for an early Miocene age is supported by index species of gastropods, attached to pieces of amber. A direct comparison with living species of Armadilliniscus allow to settle the basis for studies on the evolution of this isopod genus.