Microbial activity can be expressed in a wide range of products and forms including boring structures, biofilm-like subproducts, and framboidal pyrite precipitates. Microendolithic structures, in particular, are found in carbonate hardgrounds including tests of planktonic and benthic foraminifera and their traces can provide an extra paleoenvironmental marker of relative paleobathymetry, oxygenation, and environmental stress. Variegated traces of microbial activity including microborings, framboidal pyrite bacterial subproducts, and probable biofilms were herein studied in tests of benthic foraminifera from dysphotic to aphotic, shelf to an upper bathyal hypoxic environment. Collected material is from 6 localities in the Central Paratethys area, the Czech Republic (LOM-1 Mikulov, Hevlín), Slovakia (DNV, LKŠ-1), and Hungary (Rozalia), ranging from Rupelian to Serravalian. Microendolithic morphology was examined from resin casts obtained from the tests resulting in a total of ten ichnospecies and four other forms for which it was only possible to establish affinity on higher ranks. Levels of oxygen depletion were estimated from Benthic Foraminifera Oxygen index (BFOI). The bacterial origin of pyrite was inferred by morphology, grain size, and ẟS³⁴ values. The number of observed microboring structures gradually reduce with the decrease of oxygen content, while the precipitation of framboidal pyrite were increasing at the same time. Biofilm-like structures, apart from the suggestive morphology, also showed an enriched content of elemental iron, sulfur, and phosphorus. Raman spectroscopy shows similarities with organic pigment spectra and is still under investigation.

微生物活动可以以多种产品和形式表达，包括钻孔结构、生物膜样副产品和 framboidal 黄铁矿沉淀物。特别是在碳酸盐硬地层中发现了微内石结构，包括浮游和底栖有孔虫的测试，它们的踪迹可以提供相对古水深测量、氧化作用的额外古环境标记和环境压力。本文研究了微生物活动的各种痕迹，包括微孔、framboidal 黄铁矿细菌副产品和可能的生物膜，在从干旱到无光、货架到上深海缺氧环境的底栖有孔虫测试中进行了研究。收集的材料来自 Central Paratethys 地区、捷克共和国（LOM-1 Mikulov、Hevlín）、斯洛伐克（DNV、LKŠ-1）和匈牙利（Rozalia）的 6 个地点，范围从Rupelian 到 Serravalian。从测试中获得的树脂铸件检查了微内石器形态，结果总共有十种 ichnospecies 和四种其他形式，只有在更高级别上才能建立亲和力。根据底栖有孔虫氧指数 (BFOI) 估计氧耗竭水平。黄铁矿的细菌起源是通过形态、粒度和 ẟS ^34推断的值。随着含氧量的降低，观察到的微孔结构数量逐渐减少，同时杂粒状黄铁矿析出增多。除了暗示性的形态外，生物膜样结构还显示出富含元素铁、硫和磷。拉曼光谱与有机颜料光谱有相似之处，目前仍在研究中。