Palynoflora from an Upper Cretaceous freshwater paleolake in central India: paleoecological implications

An Upper Cretaceous paleolake near Jamsavli in the Mandla Lobe of central India has provided a unique opportunity to understand paleoecological conditions during Deccan volcanism. The sedimentary de-posits of this paleolake are dominated by freshwater aquatic and semiaquatic flora, such as algae (Pediastrum, Lecaniella), dinocysts (Pierceites deccanensis), diatoms (Aulacoseira), aquatic ferns of Salvi-niaceae (Azolla), Marsileaceae (Crybelosporites), and pollen grains of Sparganiaceae/Typhaceae (Sparga-niaceaepollenites). Such paleolakes, representing a few hundred years of lake history with only aquatic and semiaquatic biota, have rarely been documented from the Deccan volcanic province.An overview of aquatic and semiaquatic flora from the infratrappean and intertrappean beds associ-ated with the Deccan volcanic province across the Cretaceous-Paleogene shows that the floral com-munities include algal remains of Botryococcaceae, Chlorophyceae, Chlorellaceae, Cyanophyceae, Hydrodictyaceae, Oedogoniaceae, Ulotrichaceae, Zygnemataceae, dinocysts, and diatoms. Bryophytes are scarce, whereas aquatic ferns of Salviniaceae (Azolla) and Marsileaceae (Marsilea and Regnellidium) are the dominating groups in the intertrappean deposits. Aquatic and semiaquatic angiosperms show less taxonomic diversity and are represented by only five families, namely Nymphaeaceae, Typhaceae, Lil-iaceae, Acanthaceae, and Pontederiaceae. The ubiquitous presence of macrophytes and microfloral fossil remains of Zygnemataceae (Ovoidites), Salviniaceae (Azolla), Marsileaceae (Crybelosporites and Gabonis-poris), and palms, along with paleosol, indicate frost-free, warm, humid tropical to subtropical climates with intermittent dry and wet semi-arid conditions across the Late Cretaceous-early Paleocene.(c) 2022 Elsevier Ltd. All rights reserved.