Dicliptera aegyptiaca (Acanthaceae), a new species from Egypt supported by morphological characters and rbcl-based DNA barcoding

Abstract

DICLIPTERA aegyptiaca, a new species from Red Sea Coast, Egypt, is described and illustrated. Diagnostic and morphological characters that distinguish it from its allied species D. paniculata and an identification key for the two species are provided. The new species differs from D. paniculata by having an unbranched stem, a congested inflorescence with dwarf axes 1.5– 5mm long; subsessile cymules with peduncles 0.5– 1mm long. rbcl-DNA barcoding is presented for this new taxon for the first time. Phylogentic tree revealed barcode clusters for the two Dicliptera species and recognized significant interspecific variation between them. D. aegyptiaca clearly formed one clade strongly supported with a bootstrap value of 100%. Based on characters of morphology, pollen and seeds, the new species was recognized as belonging to the genus Dicliptera. On the other hand, DNA barcoding reflected clustering of all Dicliptera spp. in a large clade while D. aegyptiaca formed a non sister clade showing the utility of DNA barcoding for species identification rather than taxonomy.