Dados do Trabalho

TÍTULO

QUATERNARY MORMOOPIDAE (MAMMALIA, CHIROPTERA) FROM SOUTH AMERICA (BRAZIL)

Resumo

Although the bat family Mormoopidae has an extensive fossil record dating back at least to the Oligocene of Florida, in South America their fossil record is relatively poor, consisting of only a few Quaternary cave deposits. Mormoopid subfossils have been reported from the Holocene of Cueva Toromo, Venezuela, including representatives of Pteronotus sp. and Mormoops megalophylla. All the other SA mormoopid records come from two geological provinces in Brazil: Chapada Diamantina in the Northeast (Bahia) and Serra da Mesa in the Midwest (Goiás). Mormoopids are represented in Chapada Diamantina by huge bone-deposits in the caves Toca da Boa Vista and Barriguda, with ages varying from 155.188 ± 2.528 to 15.741 ± 424 Ka (UTh references). Mormoopids also occur in a submerged deposit in the Impossível Cave (8700 ± 50 Ka). All three caves are in the Irecê basin, the first two at the northern portion, somewhat near the São Francisco River, and the third at the very southern extreme of the basin as part of Iraquara karst. Based on cranial and postcranial evidence, the diversity of fossil mormoopids from Chapada Diamantina includes representatives of the Pteronotus parnellii species group, P. gymnonotus, and P. davyi, plus an extinct lineage of Mormoops that is unexpected since the extant distribution of this genus in South America is restricted to the northwestern portion of the continent. This biogeographic pattern contrasts with the current widespread distribution of Mormoops in Central America, including the Caribbean islands, and North America (Mexico and South of United States). An ongoing international transdisciplinary research program has as a main goal to understand phylogenetic, biogeographic, and extinction patterns related to this lineage of Mormoops from the Brazilian Northeast. Patterns of variation in forelimb morphology suggest that the extinct populations known from different (Late Pleistocene / Upper Holocene) sites in the Northeast may represent a new taxon in the M. megalophylla species complex, but confirmation awaits additional morpho-molecular approaches. Mormoopids are well represented among the remains found in three limestone caves from Serra da Mesa, including representatives of the Pteronotus parnellii species group, P. gymnonotus, and P. davyi, but no evidence of Mormoops has been found. Additionally, Serra da Mesa also provides the first fossil record of P. personatus for the South American continent, which was recovered in association with deposits with ages dated between 182,8 ± 1,2 and 121, 473 ± 5,395 Ka (UTh references). Challenges being faced in this research project, focused on the evolutionary history of mormoopids in South America, are relying essentially into two main axes: one concerning fieldwork investments to reveal chronologies and biogeographic patterns, including variables associated to the related paleoclimatic and paleoenvironmental scenarios; and the second efforts to the development of refined studies to reveal morpho-molecular patterns of variation of both extant and extinct populations.

Palavras-chave

Chiroptera, Mormoopidae, Quaternary, Chapada Diamantina, Serra da Mesa

Financiamento

CNPq (483398/2009-8), FAPESP 2017/22269-2, CONACYT (132620, 263301), UFRJ.