ESTUDIOS SOBRE RUBIACEAS MEXICANAS XVI.Psychotria lozadae una especie nuevaen la flora del estado Guerrero

摘要

The exploration of the extremely rich Mexican flora stepped into a more intensified phaseaccording to the decisions and recommendations of the XVI. Mexican Botanical Congress(Oaxaca, 2004). Within the framework of the studies in the Rubiaceae family three kinds ofactivities has been required: 1) To summarise the existing knowledge about the taxonomyof the family giving a stable base for the further explorations. 2) Extension of the collectingactivity. 3) Revision of the collections of the different federal institutions, universities andlocal authorities or societies. For fulfilling the first requirement, the monographic treatmentof Rubidceas de Mexico was published by the Akademiai Kiado, in 2006. For the further re-quirements new, hitherto not visited areas have been collected in different states and alsoseveral institutional and regional collections have been revised and determined (e.g. Floraof the state Guerrero of the UNAM, SERBO de Oaxaca, INEGI, Universities of Tabasco,Queretaro, Aguascalientes) and naturally the materials of the central collections of Mexico(MEXU, FCME, ENCB). For publishing the new findings a series of articles started in 2003,with the title: Estudios sobre Rubidceas Mexicanas. The results of the first ten articles of the se-ries are included into the monograph, but the new taxa published after 2006 are additionaldata, not included into the Rubidceas de Mexico. A new addition to the knowledge of theMexican Rubiaceae is the Psychotria lozadae a small-leaved creeping subshrub of the highmountain evergreen forests of the Sierra Madre del Sur in Guerrero, with an uncommonhabit. It belongs to the subgenus Heteropsychotria, by its bilobulate, permanent stipules. Themost closely related species is P. minarum Standl. et Steyerm. of Guatemala, which differs fromour species by its longer petioles, elliptic, nigrescent leaves, with obsolete or inconspicuos,nerves, corymbose and glabrous inflorescences, sessile or subsessile, 5-merous flowers, andglabrous hypanthium. The species is dedicated to Lucio Lozada-Perez, the excellent collec-tor and expert in the Spermacoceae tribe of Rubiaceae.