The genus Justicia (Acanthaceae) in the state of Pará, Amazon, Brazil

Abstract The taxonomic knowledge for genus Justicia in the Amazonian state of Pará, Brazil, is updated. The study was based on material from important national and international herbaria, as well as specimens collected in different vegetation types within the state, some of them kept under cultivation by the first author. Twenty five species of Justicia were recorded for Pará: J. asclepiadea, J. birae, J. calycina, J. carajensis, J. cayennensis, J. comata, J. distichophylla, J. divergens, J. gendarussa, J. laevilinguis, J. mcdadeana, J. montealegrensis, J. multiglandulosa, J. oldemanii, J. oriximinensis, J. paraensis, J. pectoralis, J. polystachya, J. potamogeton, J. pseudoamazonica, J. riedeliana, J. secunda, J. sphaerosperma, J. sprucei, J. yurimaguensis. Among these, five are new records for the state of Pará (J. asclepiadea, J. cayennensis, J. gendarussa, J. oldemanii, and J. yurimaguensis). Moreover, seven of the accepted names are lectotypified and a new name (J. oriximinensis) is proposed. A species identification key is presented alongside detailed morphological descriptions (including seed analysis), distribution and habitat information, taxonomic comments and illustrations.