A new simple-leaved species of Recchia (Simaroubaceae) from southeastern Mexico

Recchia simplicifolia, a new species from southern Veracruz, southern Tabasco and northern Chiapas, represents the first non-microphyllous simple-leaved New World species of Simaroubaceae. It differs from the other two species of Recchia in its simple leaves, cauliflory, and rain forest habitat. Its discovery may necessitate a reevaluation of the relationships of Surianaceae and Simaroubaceae. Although its distribution corresponds to a high-precipitation area which demonstrates strong affinities to the wet Central American flora and may have served as a refuge area for rain forest species during parts of the Pleistocene, its relationships are strictly with Mexican species of the dry Pacific slope, supporting the hypothesis of exchange between the wet and dry Mexican floras during the climatic cycles of the Pleistocene.