Two new species of Serjania (Sapindaceae) from Michoacán, Mexico, with notes on S. biternata

Serjania rosalindae and S. crucensis (Sapindaceae-Paullinieae), new species from the municipality of La Huacana, Michoacán, Mexico, are described, illustrated, and compared with closely related species. In addition, micromorphological features of the leaves, flowers, and pollen grains are investigated. A treatment of the endemic S. biternata from Guerrero is also included because it is a little-known taxon similar to S. rosalindae whose fruits were previously unknown. All of these taxa share capsules that are chartaceous to almost woody and septifragal, a fruit type otherwise uncommon within Serjania. The distinctive fruit morphology of these species is discussed in relation to other species of Serjania.