Myrtacean leaves from the San Jose Formation (Middle Miocene), Tucuman Province, Argentina

Fossil leaves from the San Jose Formation assigned to Myrtaceae are described herein. They were found at three localities of the quebrada de Amaicha, northwest Tucuman Province. The San Jose Formation of Middle Miocene age is the basal unit of the Santa Maria Group. The genus Myrciophyllum Engelhart is emended, a new species, Myrciophyllum tucumanensis, and Myrciophyllum sp. 1 and Myrciophyllum sp. 2 are described. The genus has brochidodromous to acrodromous leaves with intra-marginal veins, the intersecondary and tertiary veins with admedial branching pattern. Myrciophyllum tucmanensis sp. nov. has obovate leaves with 5-6 secondary veins, Myrciophyllum sp. 1 has elliptic leaves and Myrciophyllum sp. 2 lanceolate to elliptic narrow ones, both with 9-10 pairs of secondary veins. The three species are similar to leaves of the extant genus Myrciathes Berg. They resemble extant species from northern Argentina and probably integrated the tree stratum of a neotropical forest, ancestral to the present Yungas Province.