کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4682224 1635152 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The first Late Eocene continental faunal assemblage from tropical North America
ترجمه فارسی عنوان
اولین مونتاژ فونهای قاره ای اوائل پس از آمریکای شمالی گرمسیری
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
چکیده انگلیسی


• The first late Eocene terrestrial faunal assemblage from tropical North America is reported.
• This new faunal assemblage includes reptiles, mammals and hymenopteran ichnofossils.
• Several taxa are recorded for first time in the Mexican Paleogene.
• Some vertebrate taxa greatly expand southerly their former geographic distribution.
• K–Ar ages and biostratigraphy suggest a Chadronian age for this new local fauna.

To date, the terrestrial faunal record of the North American late Eocene has been recovered from its subtropical and temperate regions. We report the first late Eocene continental faunal assemblage from tropical North America, in southern Mexico. Fossil specimens were collected from mudstones that crop out in the Municipality of Santiago Yolomécatl, in northwestern Oaxaca. Previously published K–Ar ages of 32.9 ± 0.9 and 35.7 ± 1.0 Ma in overlain nearby volcanic rocks and biostratigraphy of these new localities suggests a Chadronian mammal age for this new local fauna. The assemblage is composed by two turtle taxa, Rhineura, two caniform taxa, a sciurid, a jimomyid rodent, a geomyine rodent, Gregorymys, Leptochoerus, Perchoerus probus, Merycoidodon, a protoceratid, Poebrotherium, Nanotragulus, Miohippus assinoboiensis, a chalicotherid, a tapiroid, cf. Amynodontopsis, Trigonias and the hymenopteran ichnofossils Celliforma curvata and Fictovichnus sciuttoi. The records of these taxa in northwestern Oaxaca greatly expand southerly their former geographic distribution in North America. The records of the geomorph rodents and Nanotragulus extend their former known biochronological range to the late Eocene. The hymenopteran ichnofossils in the localities suggest the presence of a bare soil after periodic waterlogging, under a sub-humid to sub-arid climate. This new local fauna represents the first glimpse of Eocene vertebrate and invertebrate terrestrial life from tropical North America.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of South American Earth Sciences - Volume 57, January 2015, Pages 39–48
نویسندگان
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