Ralph M. Wetzel

Catagonus, an "Extinct" Peccary, Alive in Paraguay

A third species of peccary, discovered in the Chaco of Paraguay, is added to the living members of family Tayassuidae. It is assigned to the genus Catagonus Ameghino, heretofore considered confined to the Pleistocene. The new peccary is conspecific with Catagonus wagneri (Rusconi), a species placed in the related extinct genus Platygonus LeConte when it was described from pre-Hispanic archeological deposits of Argentina.

THE EXTINCTION OF PECCARIES AND A NEW CASE OF SURVIVAL

The problem of extensive extinction of larger mammals at the close of the last Ice Age “is as old as the study of Quaternary mammals.”’ Two-thirds of the megafauna of the Rancholabrean age of North America disappeared by the beginning of Recent times,2 including ground sloths, giant armadillos, mammoths, mastodons, tapirs, camels, horses, giant rodents, two genera of peccaries, and the more specialized and larger predators. A symposium on this problem of extinction explored varied possible cause^,^ including the effect of postglacial desiccation4 and other climatic cause^,^ breeding period dysynchronous with climatic change,6 disea~e,~ and the ultimate conflict of advanced hominid hunting culture with its large ~ r e y . ~ J ? Mosimann and Martin2 presented a mathematical model supporting the latter theory of North American megafaunal extinction. Whether an advanced hunting culture was the cause of the extinction, and despite a paucity of direct evidence, extensive interaction must have occurred between the Amerinds and the now extinct megafauna. The following large mammals of 7-8,000 years ago, now extinct or no longer found in southeastern United States, were reportedg from Florida associated with a modern mammalian fauna and human remains: ground sloth, Megalonyx cf. M. wheatleyi; dire wolf, Canis dirus; North American spectacled bear, Tremarctos floridanus; jaguar, Felis onca augusta; sabertooth, Smilodon cf. S. floridanus; American mastodon, Mammut americanum; horse, Equus sp.; and the flat-headed peccary, Platygonus compressus. The long-nosed peccary, Mylohyus cf. M. nasutus, has been found associated with human remains of the early Archaic Period, 7-9,000 years ago, in Russell Cave, Alabama.’ A canine of Platygonus believed to be associated with a beveled Archaic spearpoint has been reported from a cave in the driftless area of Wisconsin, tentatively dated 8-10,000 years ago.’ Our finding a new, living peccary in Paraguay12 tempts me to ask if this relative of the extinct Platygonus might contribute some other viewpoint on the problems of extinction. As a new generic and specific addition to the living fauna of South America, the animal is peripheral to the problems concerning the Paleoindian and his environment in eastern North America. However, this third living peccary may, perhaps, serve in the future as a model for inquiry as it survived and its relative in North America became extinct. I will only introduce this “new” form here. A detailed account will soon be published.’ The new peccary was assigned to the genus Catagonus Ameghino, known from the lower to middle Pleistocene of Argentina, and to the species Platygonus wagneri Rusconi.12 This species, believed to be extinct, was described by R ~ s c o n i ~ ~ * ~ from pre-Hispanic archeological deposits in the province of Santiago del Estero, Argentina. It is a relict of the Pleistocene, surviving in an isolated, restricted area, the Cran Chaco of northern Argentina, southeastern

Chromosome Studies on the Silky Anteater Cyclopes Didactylus L. (Myrmec Ophagidae: Xenarthra, Edentata)

SUMMARYThe karyotype of the silky anteater Cyclopes didactylus, the smallest of the anteaters is described. A notable difference in karyotypes exists between C. didactylus (2n = 64) and the other species of the family Myrmecophagidae. Both fusion/fission as well as other mechanisms are probably involved in the reduction of the chromosome number of 64 chromosome in Cyclopes to 60 and 54 in Tamandua and Myrmecophaga, respectively.