Los géneros de la familia Euphorbiaceae en México

Abstract

THE FAMILY EUPHORBIACEAE IS ONE OF THE MOST DIVERSE FAMILIES OF AN- GIOSPERMS. IT INCLUDES 5 SUBFAMILIES, 49 TRIBES, 317 GENERA AND ABOUT 8100 SPECIES, WITH DISTRIBUTION MAINLY IN TROPICAL AND SUBTROPICAL ZONES OF THE WORLD. THE MAIN OBJECTIVE OF THIS PAPER IS TO PRESENT A PRELIMINARY CHECKLIST FOR GENERA AND SPECIES OF MEXICAN EUPHORBIACEAE, CONSIDERING THEIR DISTRIBUTION AND DE- GREE OF ENDEMISM. FOR THIS PURPOSE, THE HERBARIA MEXU, ENCB, FCME, UAMIZ, CHAPA, CICY AND CIQRO WERE CONSULTED. FROM THE DATA OBTAINED, AND AFTER REVIEWING THE LITERATURE AND COLLECTIONS, THE SYNONYMOUS NAMES WERE ELIMINATED. FIFTY GENERA AND 826 SPECIES WERE FOUND, 55.52 % OF THESE ENDEMIC TO MEXICO. EUPHORBIACEAE IS THE SIXTH FAMILY IN IMPORTANCE IN MEXICO CONSIDERING THE NUMBER OF SPECIES, AND AMONG THE FAMILIES RICHEST IN ENDEMIC SPECIES. THE LARGEST GENERA ARE EUPHORBIA (138 SPP.), CROTON (126 SPP.), CHAMAESYCE (103 SPP.) AND ACALYPHA (126 SPP.), WHEREAS THOSE GENERA WITH THEIR GREATEST CENTER OF DIVERSIFICATION IN MEXICO ARE BERNARDIA, CNIDOSCOLUS AND PEDILANTHUS; ONLY ENRIQUEBELTRANIA IS CONSIDERED ENDEMIC. IN ORDER OF IMPORTANCE, THE STATES WITH THE HIGHEST DIVERSITY (MORE THAN 100 SPECIES) ARE OAXACA, CHIAPAS, VERACRUZ, JALISCO, GUERRERO, SONORA, PUEBLA, SINALOA, TAMAULIPAS, NAYARIT AND MICHOACAN. A DICHOTOMOUS KEY TO DISTINGUISH ALL MEXICAN GENERA OF EUPHORBIACEAE IS PRESENTED, AS WELL AS DESCRIPTIONS AND REPRESENTATIVE ILLUSTRATIONS FOR EACH GENUS.