Olacaceae and Schoepfiaceae in eastern Northeast Brazil

Abstract

This study provides descriptions, identification key and illustrations of diagnostic characters, as well as comments on the distribution and habitat of species of Olacaceae and Schoepficeae occurring in the eastern portion of northeastern Brazil, this area includes the states of Alagoas, Ceará, Paraíba, Pernambuco and Rio Grande do Norte. The morphological descriptions are based on samples collected during field expeditions (2017-2019) and analysis of herbarium specimens. Were recorded five species in four genera belonging to the family Olacaceae (Cathedra rubricaulis, Dulacia gardneriana, Heisteria ovata, H. perianthomega and Ximenia americana) and one of Schoepfiaceae (Schoepfia brasiliensis), these species occur mainly in Atlantic Forest domain (Lowland and Montane Forests) are also registered in Caatinga and Cerrado domains. The distribution of D. gardneriana and H. perianthomega was expanded, to the states of Rio Grande do Norte and Paraíba, respectively. The main vegetative characters useful for specific delimitation are presence/absence of armed branches, petiole dorso-ventrally flattened or cylindrical and nerves impressed or flat on the adaxial surface. The presence/absence of staminodes, of a pubescent ovary and hypogynous disc, as well as floral pedicel size and diameter of accrescent calyx in fruits, are the most important reproductive characters for species determination.