Desenvolvimento da antera de Caryocar brasiliense e sua importância na sistemática e evolução de Malpighiales

Abstract

Caryocaraceae is a neotropical family with a complex taxonomic history and currently circumscribed inside Malpighiales. Notwithstanding, molecular studies have still not sufficient to establish family relationships within the order. As embryology and floral anatomy and development can be successfully used to solve taxonomic problems, hypotheses suggesting those studies could be helpful to Malpighiales circumscription has been raised. As the embryology of Caryocaraceae and 11 other Malpighiales families is still unknown, our study intends to narrow some of these gaps by studying the embryology of the anter and pollen grain of Caryocaraceae. For this, fertile branches of Caryocar brasiliense were collected in the nearness of the Uberlândia city, Minas Gerais. The material was processed using standard light microscopy and SEM techniques. The anther wall development of C. brasiliense is of the Dicotyledonous, with the persistent epidermis, fibrous endothecium, an ephemeral middle layer, and secretory type tapetum. Cytokinesis is simultaneous, originating tetrahedral tetrads. The pollen grain is tricolporate, spheroidal prolate, with reticulated ornamentation, and has two cells at dispersion. Our results showed that Caryocaraceae differs from relative families, mainly because it presents Dicotyledonous type development. Hereafter, we intend to study the ovule development in order to add more comprehensive data that may contribute to the circumscribing of Caryocaraceae within Malpighiales.