Produced by Chris Curnow, Joseph Cooper, Josephine Paolucci and the Online Distributed Proofreading Team at https://www.pgdp.net. The Subspecific Status of Two Central American Sloths BY E. RAYMOND HALL and KEITH R. KELSON University of Kansas Publications Museum of Natural History Volume 5, No. 24, pp. 313-317 November 21, 1952 University of Kansas LAWRENCE 1952 University of Kansas Publications, Museum of Natural History Editors: E. Raymond Hall, Chairman, A. Byron Leonard, Edward H. Taylor, Robert W. Wilson Volume 5, No. 24, pp. 313-317 November 21, 1952 University of Kansas Lawrence, Kansas PRINTED BY FERD VOILAND, JR., STATE PRINTER TOPEKA, KANSAS 1952 25-4545 [Transcriber's Note: Words surrounded by tildes, like ~this~ signifies words in bold. Words surrounded by underscores, like _this_, signifies words in italics.] The Subspecific Status of Two Central American Sloths BY E. RAYMOND HALL and KEITH R. KELSON New name combinations for two kinds of Central American sloths that heretofore have stood in the literature as nominal species are given below, along with the evidence supporting their relegation to subspecific rank. Research assistance has been provided from a contract (NR 161-791) between the Office of Naval Research, Department of the Navy, and the University of Kansas. ~Bradypus griseus ignavus~ Goldman Goldman (Smiths. Misc. Coll., 60(22):1, February 28, 1913) named the three-toed sloth from extreme eastern Panamá (Marraganti: 1 specimen, the type) and northwestern Colombia (Atrato River: 2 specimens) as _Bradypus ignavus_. He characterized the newly-named species as differing from _Bradypus griseus_ (type locality Cordillera de Chucu, Veragua, Panamá) and _Bradypus castaneiceps_ (type locality, Chontales, Nicaragua) in "nasals shorter, with anterior border concave or emarginate, the emargination deepest at median suture; squamosal arm of zygoma broader, more rounded, less acutely pointed anteriorly; palate less deeply grooved posteriorly; symphysis of mandible less produced anteriorly beyond plane of first molars." Later, Goldman (Smiths. Misc. Coll., 69(5):57-58, April 24, 1920) arranged _Bradypus castaneiceps_ as a subspecies of _B. griseus_, reaffirmed the full specific identity of _Bradypus ignavus_, and identified specimens from Tapalisa, Cituro, and Real de Santa Maria, all in eastern Panamá, as belonging to _B. ignavus_. In order to satisfy ourselves about the taxonomic relationship of _B. ignavus_ to _B. griseus_, we have examined the following materials in the American Museum of Natural History: _ignavus_: Panamá: Cituro (No. 38191), Tapalisa (No. 38102), Real de Santa Maria (Nos. 37619-37621); _griseus_: Panamá: La Chorrera (No. 31427); Costa Rica: Juan Viñas (No. 2824), Palmar (No. 139313), Vijagual, San Carlos (No. 139833); _castaneiceps_: Nicaragua: Chontales (Nos. 28477 and 28478).