A New Species of Casearia (Flacourtiaceae) from Mexico

Abstract

Casearia guevarana, a new species of Flacourtiaceae from the coastal dunes of the Natural Reserve Morro de la from the states of Veracruz and Tabasco, Mexico, is described and illustrated. Its affinities with the closely related species C. aculeata Jacquin and C. obovata Schlechtendal are discussed. This new species differs from its congeners by having broadly obtuse leaf apices, large, six-channeled fruits, and larger more numerous seeds. RESUMEN. Se describe como nueva a Casearia guevarana (Flacourtiaceae) de las dunas costeras de la Reserva Natural E1 Morro de La Mancha, Veracruz y Tabasco, Mexico. Esta nueva especie esta cercanamente relacionada con Casearia aculeata Jacquin y C. obovata Schlechtendal, de las que se distingue por presentar el apice de las hojas ampliamente obtuso, frutos 6-acanalados y de mayor tamano, con semillas mas grandes y mas numerosas. Ke words: Casearia, coastal, dunes, Flacourtiaceae, La Mancha, Mexico, Tabasco, Veracruz. In 1998, during an inventory of trees and shrubs associated with an evergreen seasonal rainforest at the Nature Reserve and Clenter for Coastal Research at La Mancha ((LICOLMA) in Veracruz! Mexico, a tree rarely seen in the middle stratum of the forest was sampled and reported. At the time, this tree was totally lacking reproductive structures so that it was only possible to classify it with any certainty to the genus Casearia (Flacourtiaceae). However, during two years subsequent to this initial find, flowers (2000) and fruits (2001) were obtained. After having examined and compared vouchers of C. aculeata and C. obovata with those recently collected from the Natural Reserve of La Mancha, it NOVON 13: 30-33. 2003. was found that they corresponded to an undescribed species. Based upon this additional information this specimen was considered to represent a nez species. Its detailed description is reported below. Caseflria Jacquin is a pantropical genus of about 180 species of trees and shrubs. It is most diverse in (sub)tropical Central and South America, where some 75 species occur, including 8 in Veracruz. The genus is subdivided into six sections, the largest and only one to occur outside of the Neotropics, is section Casearia. Three of the sections are represented in Veracruz: sect. Crateria, sect. Pipcerea, and sect. Case(lria. Section Casearia is further divided into six informal groups, three of which occur in Veraeruz i.e. Nitidae Aculeatae, and Decandrae. The newly described Casearia guevarana has an undivided style free stamens, and free interstaminal disc lobes. These characters place the species in Casearia sect. Casearia. The following characters place the species in section Casearia, group Aculeatae; an undivided style, at times obsolete, and capitate stigma; plants generally with spines, at times not present in herbarium vouchers; and stamens generally 8, flowers more or less tubular, base oltuse-truncate often slightly swollen just before flowering. Two other species of the Aculeatae group occur in Veracruz, C. aculeata and C. obov-