Robinson & Taylor 1999b (Article) Pitcairnia

A rejection of Pepinia (Bromeliaceae: Pitcairnioideae) and taxonomic revisions

Author(s):—H. Robinson & D.C. Taylor in Grant, J.R. - Florilegium Luctatori Botanico Dedicatum - A Tribute to Lyman B. Smith (1904-1997)

Publication:—Harvard Papers in Botany 4(1): 203-217. (1999)

Abstract:—The recent generic subdivision of Pitcairnia L’ Her., and recognition of an expanded segregate genus Pepinia Brong. in André by Varadarajan and Gilmartin is rejected. The stated difference between the genera was seed structure, alate or naked in Pepinia and bicaudate in typical Pitcairnia. Analysis of the seeds shows a more complex seed variation, varying from the amphigenus cortication of Pitcairnia aphelandrWora Lem. (subg. Pepinia) to the narrowly winged and bicaudate form of typical Pitcainzia and the broadly alate form of many South American species. Scanning Electron Microscopy (SEM) is employed to illustrate the gradation. Seed variation, by itself, proves unreliable for the proposed generic delimitation. Other characters against which the seed character is tested include the arrangements of chlorenchyma, and adaxial or abaxial water storage tissue adjacent to vascular bundles as seen in cross sections of Pitcairnia leaves. The latter anatomical structures are considered significant and unlikely to have evolved more than once in the broad concept of Pitcairnia. The dif ferent foliar modifications occur in both proposed subgenera based on seed type with little correlation to seed variation. As a result, the genus Pepinia is returned to the synonomy of Pitcairnia without distinction at the subgeneric level. forty-two species that have been transferred to Pepinia are listed under their proper names in Pitcairnia with six new combinations and two required new names.

Keywords:—Bromeliaceae, leaf anatomy, morphology, Pepinia, Pitcairnia, Pitcaimioideae, taxonomy

Published names (7):

Pitcairnia alexanderi
Pitcairnia cristalinensis
Pitcairnia harrylutheri
Pitcairnia hooveri
Pitcairnia neglecta
Pitcairnia sanguinea
Pitcairnia tatzyanae