INVESTIGADORES
ZURITA Alfredo Eduardo
congresos y reuniones científicas
Título:
PARALLELISMS BETWEEN FOSSIL AND EXTANT FAIRY ARMADILLOS (CHLAMYPHORINAE, CINGULATA): TRACKING ITS EVOLUTIONARY HISTORY
Autor/es:
BARASOAIN, DANIEL; SUPERINA, MARIELLA; TOMASSINI, RODRIGO; ZURITA, A. E.; MONTALVO, CLAUDIA
Lugar:
Rio de Janeiro
Reunión:
Workshop; CICX Congresso Internacional de Conservacao de Xenarthran; 2020
Resumen:
mong Cingulata (Xenarthra), the Chlamyphoridae Chlamyphorinae represent the last recognizedsubfamily and, according to molecular data, the last to have diverged. Their representatives arecommonly known as fairy armadillos or "pichiciegos", and are considered one of the most elusiveliving mammals. The current diversity includes two allopatric species: Chlamyphorus truncatusHarlan, 1825 (pink fairy armadillo or lesser "pichiciego"), restricted to central Argentina, inhabitingdry grasslands and sandy plains, and Calyptophractus retusus Burmeister, 1863 (greater"pichiciego"), distributed along the Gran Chaco in northern Argentina, western Paraguay andsouthern Bolivia, inhabiting in soft sandy soil environments. Though it is believed that someanthropic activities such as agricultural development and livestock farming represent potentialthreats to their populations due to habitat loss, the reality is that both species are classified as DataDeficient by the IUCN Red List. This is due, particularly, to the great sampling challenges derivedfrom the fossorial and nocturnal habits of these armadillos, which are believed to have naturallylow population densities. From a paleontological perspective, fossils of Chlamyphorinae areextremely scarce. All remains, recovered from Central Argentina, belong to the recently describedtaxon Chlamydophractus dimartinoi (Barasoain, Tomassini, Zurita, Montalvo and Superina, 2020).This extinct taxon shows, unlike living fairy armadillos, a thick dorsal carapace, a well-definedornamentation pattern on the exposed surface of the osteoderms and rump plate, and a morehorizontal position of the rump plate. The great morphological affinity of the mandible andmolariforms between fossil and living species suggests similar diet habits. However, the postcranial anatomy (e.g. humerus, dorsal carapace, and rump plate) suggests that Chlamydophractus would have been a good digger, but, unlike extant species, would not have had "fully" subterranean habits. Records of Chlamydophractus are restricted, at the moment, to the late Miocene (~9-10 Ma.) of Buenos Aires, La Pampa , and San Juan provinces. At this point, it is noteworthy that the provenance of all fossil records coincides with the current geographical distribution range of Chlamyphorus truncatus; hence, it is possible to infer the presence of chlamyphorines along most part of central Argentina at least for the last ~10 Ma. Contrary, to date no fossil records have been found in other Cenozoic deposits within the range of C. retusus. These records are, however, still so scarce to propose specific hypotheses on the evolution of this lineage, particularly because there is an important gap in the fossil record from the late Miocene to recent. Even though the available data of fossil chlamyphorines can still be considered as insufficient, the increasing knowledge of their evolutionary history, biogeography, biology, and ecology can eventually derive in the development of effective conservation strategies.