On Eurymerodesmidae, a new family of Diplopoda (Strongylosomidea), and a new Arkansas species of Eurymerodesmus

Eurymerodesmidae , fam. nov. This family is set up to include certain genera from the Mississippi Valley, Southeastern and Southwestern States formerly included in Xystodesmidae, or in Chelodesmidae from which it can be separated by the following characteristics: mandibles with a tongue-like protuberance on the anterio-ventral margin of the pars basalts; unspined sternites, coxae, and prefemurs; male sternites setose, often with lobes; keels narrow to moderately wide; male gonopods consisting of a large basal division and a small telopodite which is simple, either setose or glabrous, and caudally directed; gonopodal opening of male with anterior margin always recurved medially (figure 2) and variously modified withlobes and setae, the lobes on the caudal and lateral margins. Itresembles Xystodesmidae inhaving smooth tergites with the keels horizontal to somewhat depressed, their lateral margins raised and not serrated