Spirodela Schleid. is one of the most abundant and widespread giant duckweeds (Araceae: Lemnoideae), although its fossil record remains relatively unexplored. We present a well-preserved, impressed and compressed fossil rosette bearing four leaves similar to this extant free-floating great duckweed from the early Eocene (Palana Formation) sedimentary sequences of Gurha Lignite Mine, Rajasthan, western India. We infer its taxonomic position based on phylogenetic analysis using macromorphological traits and compare it with other modern and fossil species of Lemnoideae. The fossil specimen is characterized by four peltate sessile leaves (one mother, two daughters, and one granddaughter) arranged spirally in a rosette, leaves with campylodromous venation, and the presence of stolons and adventitious roots. After a thorough comparison, we described our Eocene specimen as a new genus and species, namely Eospirodela indica Ali, Almeida et Khan gen. et sp. nov. Together with other fossils reviewed from the literature, this new taxon helps to elucidate the evolution of duckweeds. Our finding strongly supports the existence of a freshwater ecosystem complementing the earlier published data on the Rajasthan Basin during the early Eocene (55 ± 10 Ma), in contrast to the present desert vegetation of the region. It also throws light on the paleoecological and paleobiogeographical history of duckweeds.