Paleocene larger foraminifera from the Yucatán Peninsula (SE Mexico)

[摘要] The larger foraminifera found in the material from the Chichen Itzá Formation of Campeche (SE Mexico) were studied in detail. The architectural analyses allow the description of four new species and a new genus, namely, two agglutinated conical foraminifera, Coskinolina yucatanensis n.sp. and Pseudofallotella drobneae n.gen. n.sp., one new alveolinid, Borelis hottingeri n.sp., and one new rotaliid, Dictyoconoides boneti n.sp. The larger foraminifera of the Chichen Itzá Formation are distributed across two different associations: one includes Pseudofallotella drobneae, Neotaberina sp., Rhabdorites sp., Borelis hottingeri, Dictyoconoides boneti, Kathina sp., Miscellaneidae, Ranikothalia soldadensis and Hexagonocyclina cristensis, while the other assemblage is composed of Coskinolina yucatensis, Fallotella causae, Rhabdorites sp., Borelis floridanus and Cincoriola cf. ovoidea. Some of these genera, including Neotaberina and Dictyoconoides, are cited in the Caribbean paleobioprovince for the first time in this paper. The first association is dated as Thanetian (SBZ 3? to SBZ 4) by the presence of Ranikothalia soldadensis. Though the age of the second association remains uncertain, a similar age has been inferred.

[学科分类] 地质学

[关键词] Paleocene;Yucatán;Mexico;larger foraminifera;biostratigraphy