Lectotypification of Fimbristylis subtrabeculata (Cyperaceae), an Endemic Species of India

Fimbristylis subtrabeculata C.B. Clarke is an endemic Indian species of Cyperaceae originally described from material collected in the Nilgiri Hills. During a revisionary study of the genus Fimbristylis Vahl in India, the name F. subtrabeculata was found to lack a formally designated type. The present study therefore examined the protologue and available original material and traced relevant specimens preserved at CAL, BM, and K. Three specimens collected by J.S. Gamble from the type locality in May 1886 were evaluated against the diagnostic features given in the protologue. Among these, the specimen preserved at CAL under barcode CAL0000001761 was found to be the best-preserved original material and to show the diagnostic characters most clearly. It is consequently designated here as the lectotype of F. subtrabeculata, while the corresponding specimens at BM and K are treated as isolectotypes. The study also provides taxonomic notes concerning the distinction of F. subtrabeculata from morphologically similar taxa, with particular attention to nutlet characters and the historical comparison with F. subbulbosa and F. kingii. This assessment follows the nomenclatural provisions applied in the manuscript and is supported by the associated specimen evidence. The selected lectotype clarifies the application of the name and provides a stable nomenclatural basis for subsequent taxonomic, floristic, and herbarium-based work on Fimbristylis in India.