New Species of Justicia and Razisea (Acanthaceae) from Costa Rica, with Taxonomic Notes

Abstract

New species of Justicia and Razisea are described from the Caribbean lowlands of northern Costa Rica. Justicia sarapiquensis sp. nov. is an unusual vine with large, magenta bracts and white, villous corollas. While morphologically most similar to several large-bracted South American justicias, the echinulate pollen grains of this species suggest a relationship with Rhacodiscus. This genus was distinguished fromJusticia on the basis of echinulate pollen and appears to be an artificial grouping of species better placed within Justicia. Clarification of the relationships of Justicia sarapiquensis will await resolution of this large and taxonomically difficult genus as a whole. The four species currently placed in Razisea share several unusual features including monothecate anthers and corolla with the upper lip strongly reduced and the lower lip barely distinct from the tube. Pollen analysis of Razisea wilburii sp. nov., along with literature reports of pollen of the remaining species, indicates that this genus is incorrectly placed in Justiceae, Odontoneminae. Based on pollen evi- dence, as well as the long-recognized similarity between Razisea and Kalbreyeriella, it is recommended that Razisea be moved to Justiceae, Justiciinae. In the course of field work in the Caribbean lowlands of northern Costa Rica, previously undescribed species belonging to two genera of Acanthaceae were discovered. This region of Costa Rica is particularly poorly known botanically and it is expected that further collections will result in a better understanding of the ranges of these two species. The extensive collecting being carried out toward completion of a flora for the La Selva field station of the Organization for Tropical Studies will greatly expand our knowledge of the plants of this extremely diverse area.