Abstract
Dipcadi (Scilloideae: Asparagaceae) is a genus of bulbous monocots with approximately 40 species, of which 13 occur in India. Species delimitation within the genus has been troublesome hindering a comprehensive phylogenetic analysis. The most recent phylogeny of the subfamily Ornithogaloideae included six species of Dipcadi only from Africa. Here, we reconstructed the phylogeny of Ornithogaloideae including 23 accessions of Indian Dipcadi. The phylogenetic analyses were based on nucleotide sequences of three plastid regions (rbcL, matK and trnL-F spacer) and one nuclear region (ITS). Pseudogaltonia clavata exhibited sister relationship to Dipcadi. Our combined nuclear + plastid dataset analyses revealed monophyletic Dipcadi with four clades, Clade I-IV. Clade I, II and III included mainly Indian species whereas Clade IV were mostly African species. Clade I included nine taxa including our newly described species D. mukaianum. The new species was phylogenetically placed along with D. erythraeum, D. saxorum and D. ursulae. Morphologically, the species resembled D. montanum and D. ursulae but differed in characters such as tepal cohesion, number of ovules per locule and foul-smelling flowers. Clade II and III included 11 and six taxa, respectively. D. erythraeum which has a native range from Egypt to western India was found in Clades I and IV. The widespread Dipcadi species, viz. D. erythraeum and D. serotinum showed polyphyly however, the monophyly of Dipcadi is established. Further work on the historical biogeography of Dipcadi on the subfamily Ornithogaloideae with more genetic data will yield insights how aridification of the landscape has shaped the evolution of the geographical clades.