Taxonomic study of Dilleniaceae and Sapotaceae families in Serra do Cipó, Minas Gerais, Brazil

Abstract

This project is a survey of the family Dilleniaceae (Dilleniales, Eudicotiledoneae “Core”) and Sapotaceae (Ericales, Eudicotiledoneae) in the Serra do Cipó region. This formation is located in the Espinhaço Range of mountains (Cadeia do Espinhaço), which extends from the State of Minas Gerais to the State of Bahia (Brazil). The Serra do Cipó is situated mainly in the municipality of Santana do Riacho, Minas Gerais, between 19º12’-19º20’S and 43º30’S – 43º40’W, with an altitude between 800-1300m; the soils of that area are usually sandy and shallow, with many outcrops (quartzites and sandstones). The vegetation types are diversified, with gallery forests, “capões” (separated forest clumps) and “cerrado” on slopes. Above 1000m a field-type vegetation physiognomy is dominant, called “campos rupestres”. The region is one of the richest in plant diversity in the world, with many endemic species. Floristic studies in the area began in 1972, and since that period more than 70 taxonomic treatments have been published, being the study of Dilleniaceae and Sapotaceae a part of this project. The family Dilleniaceae is small, with ca. 12 genera and 300 species, and a distribution mainly pantropical. They are shrubs, trees or lianas, with alternate and simple leaves. The inflorescences are generally panicles, rarely occur solitary flowers. The flowers are 3-5merous, usually bisexual, with numerous stamens. The fruits are berry or capsule. A preliminary account of the family on Serra do Cipó, published in 1987, included 2 genera (Davilla and Doliocarpus) and 5 species. The Sapotaceae is a medium-sized family, with ca. 53 genera and 1100 species, and also has a pantropical distribution. They are shrubs or trees, with alternate and simple leaves. The fasciculate inflorescences are axillary, ramiflorous or cauliflorous. The flowers are 4-5(-18)merous, unisexual or bisexual, not showy, with stamens usually on the same number or twice the number of the petals. The most fruits are berry. Latex is usually present in leaves, stems and fruits. The preliminary account published in 1987 on Serra do Cipó included 2 genera (Chrysophyllum and Pouteria) and 3 species. The project will be carried out with the usual methods in plant taxonomy: consultation of specialized literature, visit to herbaria, loans of materials, study of exsiccate, and fieldwork. Keys to the genera and species, descriptions and illustrations, comments on the geographic distribution, phenology and variability of the species will be also provided.