Preliminary notes on Justicia (Acanthaceae) in Peru

Justicia L. is the most species-rich genus of Acanthaceae in Peru and is here accepted in its broader traditional circumscription. The present paper marks a preliminary step towards a complete revision of the genus in Peru. Taxonomic notes and full synonymy are provided for 45 species including twenty-one new species, all apparently endemic to Peru: Justiciaangustituba J.R.I.Wood & R.Villanueva, J.baguensis J.R.I.Wood & R.Villanueva, J.bambusiformis J.R.I.Wood & R.Villanueva, J.chamaecaulis J.R.I.Wood & R.Villanueva, J.cajamarcensis R. Villanueva & J.R.I.Wood, J.discolor J.R.I.Wood & R.Villanueva, J.falcifolia J.R.I.Wood & R.Villanueva, J.huallagensis R.Villanueva & J.R.I.Wood, J.hyalina J.R.I.Wood & R. Villanueva, J.lactiflora J.R.I.Wood & R.Villanueva, J.longibracteata J.R.I.Wood & R.Villanueva, J.oppositiflora R.Villanueva & J.R.I.Wood, J.oxapampensis R. Villanueva & J.R.I.Wood, J.rojasiae R.Villanueva & J,R.I.Wood, J.saccata R.Villanueva & J.R.I.Wood, J.sagasteguii J.R.I.Wood & R.Villanueva, J.schunkei J.R.I.Wood & R. Villanueva, J.spathuliformis R.Villanueva & J.R.I.Wood, J.tumbesiana R.Villanueva & J.R.I.Wood, J.valenzuelae J.R.I.Wood & R.Villanueva and J.werffii J.R.I.Wood & R.Villanueva. New subspecies, subsp. machupicchuensis J.R.I.Wood & R.Villanueva of J.alpina Lindau and subsp. filisepala J.R.I.Wood & R.Villanueva of J.discolor are described. The genus Tessmanniacanthus Mildbr. is united with Justicia, the only species in the genus, T.chlamydocardioides Mildbr. being treated as Justiciachlamydocardioides (Mildbr.) R.Villanueva & J.R.I.Wood. Justicialoxensis Wassh., J.poeppigiana (Nees) Lindau, J.sessilifolia (Lindau) Wassh., J.soukupii (Standl. & F.A. Barkley) V.A.W.Graham and J.tenuistachys (Rusby) Wassh. & J.R.I.Wood are treated as synonyms respectively of J.chimboracensis Wassh., J.secundiflora (Ruiz & Pav.) Vahl, J.alpina Lindau, J.radicans Vahl and J.tenuiflora Ruiz & Pav. Fourteen names are lectotypified. The paper is copiously illustrated with line drawings, photographs and pollen images. Distribution maps supplement the information on ecology and distribution provided for all species discussed.