Artificial chemical degradation of some extant cyanobacteria with special reference to Precambrian contaminants- A cautionary note-II

Abstract

The paper is a cautionary note to all Precambrian palaeobiologists, using palaeopalynological techniques for the extraction of microfossils from Precambrian sediments. It deals with problems of contamination in palaeopalynological preparations. The effect of mineralic acids (HCI and HF) on some common cyanobacteria, viz., Microcystis, Nostoc, Oscillatoria, Lyngbya and Scytonema, has been discussed. It has been shown that the extant cyanobacteria after treatment with these mineralic acids show morphological similarities with many Precambrian microfossils. Therefore, there is a need to exercise more vigil while ascertaining the authenticity and affinity of the microfossils recovered through palaeopalynological techniques specially from Precambrian sediments.