Table Of Content

Merger of the Monotypic Genus Farringtonia with Siphanthera (Melastomataceae) Frank Almeda and Orbelia R. Robinson Department of Botany, California Academy of Sciences, Golden Gate Park, San Francisco, California 94118-4599, U.S.A. Abstract. Phylogenetic studies based on mor¬ continued recognition of a monotypic genus. The phological data show that Farringtonia, a monotyp¬ malpighiaceous cauline hairs of F. fasciculata are ic genus originally placed in the Microlicieae but very similar to those found in another, as yet un¬ recently assigned to the Melastomeae, forms part of described species of Siphanthera from Amazonian a small clade nested within the genus Siphanthera. Brazil. Thus, continued recognition of Farrington¬ Because these genera form a monophyletic group, ia, a monotypic genus nested within a clade of the Farringtonia and Siphanthera are merged and the larger, diverse Siphanthera is inconsistent with our new combination, Siphanthera fasciculata, is pro¬ attempt to provide a phylogenetic classification. posed. The single species of Farringtonia is here trans¬ ferred to Siphanthera, a monophyletic South Amer¬ The genus Farringtonia was established by ican genus defined by a 4-merous flower, 2-locular Gleason (1952) for a single Venezuelan collection ovary, and lacrimiform to vaguely reniform, areolate made by Julian A. Steyermark at the southeastern seeds. A description, distributional data, and hab¬ base of Cerro Duida in the state of Amazonas. In itat notes are included in our treatment of Si¬ the protologue, Gleason suggested a close relation¬ phanthera for the Flora of the Venezuelan Guayana ship between Farringtonia and Siphanthera Pohl and will be amplified in our forthcoming monograph based on such shared characters as 4-merous flow¬ (Almeda & Robinson, in prep.). ers and rostrate anthers. The distinctive features that, in Gleason's view, set Farringtonia apart from Siphanthera fasciculata (Gleason) Almeda & O. other inelastome genera and species known to him Robinson, comb. nov. Basionym: Farringtonia at the time included its stoutly subulate anthers, fasciculata Gleason, Fieldiana, Bot. 28: 426. large anther appendages, malpighiaceous cauline 1952. TYPE: Venezuela. Amazonas: between hairs, and fascicled Empetrum-Uke leaves. Esmeralda Savanna and the southeastern base In the course of preparing a monograph of Si¬ of Cerro Duida, 22 Aug. 1944, Steyermark phanthera we have conducted a comprehensive 57837 (holotype, F; isotypes, GH, NY, US). character analysis of Siphanthera, Farringtonia, Acknowledgments. We thank Paul E. Berry and and numerous possible sister genera in the Microli¬ Kay Yatskievych for their assistance in arranging, cieae and Melastomeae, the two tribes to which Si¬ selecting, and dispatching a loan of Siphanthera phanthera has been assigned (Gleason, 1952; Ren¬ from VEN via W IS and to the curators and staffs ner, 1993). Our phylogenetic studies of these of the following herbaria for making material under genera using vegetative and reproductive charac¬ their care available for study: A, BM, BR, C, CAS, ters provide consistent and unequivocal evidence DS, F, G, GH, GOET, HB, INPA, K, LAM, LE, M, that Farringtonia and Siphanthera form a mono¬ MG, MO, NY, P, R, RB, S, SP, U, UB, UEC, US, W. phyletic group, because F. fasciculata Gleason and S. cordifolia (Bentham) Gleason are sister taxa nest¬ Literature Cited ed in a small clade within Siphanthera. Among the characters Gleason used to emphasize the generic Gleason, ft. A. 1952. Melastomaceae. Pp. 424—438 in J. distinctiveness of Farringtonia, only the apomorph- A. Steyermark, Botanical exploration in Venezuela—II. Fieldiana, Bot. 28: 243-447. ic Ernpetrum-\ike leaves appear to be noteworthy Renner, S. S. 1993. Phytogeny and classification of the in circumscribing the species, but none of these or Melastomataceae and Memecylaceae. Nordic J. Bot. 13: any other characters have diagnostic value in the 519-540. Novon 9: 131. 1999.