Identity and taxonomic affinity of some members of the Amaranthaceae from the Galápagos Islands

ELIASSON, U. H. 1985. Identity and taxonomic affinity of some members of the Amaranthaceae from the Galápagos Islands. The type species of Pleuropetalum, P. DarwiniI, is endemic to the Galápagos and is morphologically closer to P. pleiogynum than to P. sprucei. Pleuropetalum pleiogynum has a wider distribution than previously assumed, ranging from Costa Rica to Peru. Amaranlhus anderssonii is closely related to A. urceolatus, a species of the Pacific coast of S America, and to A. berlandieri, a species of Texas and NE Mexico. Amaranlhus squamulatus, previously regarded as endemic to the Galápagos, is reported from the Guayas province of Ecuador. The genus Galápagosus, proposed for Amaranlhus sclerantoides, is rejected. Lithophila scirpoides, an overlooked taxon from the Galápagos, is believed to be an aberrant specimen of L. radicala. Lithophila subscaposa from the islands of Santiago and Pinzon differs morphologically from the specimens of Floreana. Iresine edmonstonii, probably erroneously reported from the Galápagos, is conspecific with J. angusti/olia. Blutaparon rigidum is morphologically divergent from other members of the genus, being adapted to arid conditions, and is assumed to be extinct.