Taxonomia de Ochnaceae DC. (Malpighiales) do Estado do Maranhão, Brasil.

Abstract

The state of Maranhão has a unique vegetation structure, which, as an ecotone region, tends to contain species from both the Amazon and Cerrado domains. Although it has many published floristic surveys, especially in the coastal zone, the state still lacks more in-depth taxonomic treatments of specific taxa, such as Ochnaceae. Ochnaceae belongs to the order Malpighiales and has approximately 642 species distributed in 37 genera. Of the 210 species occurring in Brazil, only 16 have been recorded in Maranhão to date distributed in two genera: Ouratea Aubl., with 13 representatives, and Sauvagesia L., with three. Aiming to confirm the occurrence of these species and gather new data on the taxonomy of the family in the state, we present in this work the taxonomic treatment of Ochnaceae from the state of Maranhão, based on collecting expeditions on São Luís Island, campinaranas environment in the extreme west of the state, part of the Legal Amazon in the Gurupi Biological Reserve, and analysis of the herbaria collections BMA, CCAA, HABIT, MAR, and SLUI in Maranhão, IAN and MG in Pará, CEN and UB in the Federal District, in addition to specimens available in virtual collections. As a result, six new records were identified based on the Flora e Funga do Brasil: three in Ouratea—O. parvifolia (A.St.-Hil.) Engl., O. salicifolia (A.St.-Hil. & Tul.) Engl., O. spectabilis (Mart.) Engl.—and three in Sauvagesia—S. deflexifolia Gardner, S. sprengelii A.St.-Hil. and S. tenella Lam., as well as one new synonym. This volume also reports on Dr. Emil Snethlage's travel in Maranhão and the importance of his collections for Ochnaceae. The new records and nomenclatural changes demonstrate the importance of taxonomic work even in locations with good sampling, especially when involving fieldwork. This work is relevant for recognizing local flora, updating species distribution data in the state, and for providing information that can support future biogeographic, molecular, and ecological research.