Two New Species of Aspidosperma (Apocynaceae) from Northeast Brazil and a Monograph of the Species from Ceara State

Abstract

In this study, we describe two new Aspidosperma species, A. castroanum and A. confertiflorum. We also reestablish Aspidosperma oliganthum as a species and provide a monograph of Aspidosperma in the state of Ceara in Northeast Brazil. We record the occurrence of Aspidosperma brasiliense, A. cuspa, A. aff. limae, A. multiflorum, A. oliganthum, A. pyrifolium, and A. subincanum, along with our two newly described species. The majority of these species are widely distributed in Northeast Brazil, except for Aspidosperma oliganthum, which has previously been recorded only in Bahia state, and our two new species, of which one is endemic only to Ceara and the other is endemic to Ceara and the neighboring Brazilian state of Piaui. Aspidosperma pyrifolium is the most widely recorded and is distributed across the Caatinga in lowland regions of Ceara, while the other species are primarily associated with plateau forests and generally have a disjunct distribution.