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: Justicia angustituba 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 Justicia chlamydocardioides (Mildbr.) R. Villanueva & J. R. I. Wood. Justicia loxensis 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.