A new kinorhynch, Echinoderes spinifurca, is described from the Atlantic coast off Fort Pierce, Florida. The species is characterized by the presence of middorsal spines on segments 6 to 10 and lateral spines/tubules on segments 4 and 7–12. The tergal furca (tergal extension) is extraordinarily long, constituting 9.3–12.9 percent of the trunk length, and this distinct character makes it easy to distinguish the species from all other species of Echinoderes. Echinoderes spinifurca occurs in shell gravel and mixed shell gravel with sand, and coexists with Echinoderes horni, Zelinkaderes sp., and two undescribed cyclorhagid taxa.