Importancia biocronoestratigráfica e implicaciones ambientales del género Saccocoma Arachnoidea (Bronniman, 1955), en el sureste de Mexico, durante el Tithoniano Medio

Noemí Aguilera Franco y Sonia Franco Navarrete

Gerencia de Investigación Aplicada en Geociencias, Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas No. 152. México D.F. 07730

Abstract

Acoording lo paleontological reconstruction and a taxonomic review Lombardia Bronnimann 1955 is considered as synonyrnous of Saccocoma Agassiz, 1836. It proposed only the specie Saccocoma arachnoidea as biocronologic marker of Middle Tithonian rocks of Southeastern of México. These rocks were deposited in Kimmeridgian through drowned platfonn setting posibily by an anoxic event.