Saraiva 2013 (Dissertation) Pitcairnia

Filogenia morfológica de Pitcairnia L'Hér. (Bromeliaceae-Pitcairnioideae)

Author(s):—D.P. Saraiva

Publication:—JARDIM BOTÂNICO DO RIO DE JANEIRO (2013).

Abstract:—One of the largest and most widely distributed genera of Bromeliaceae is Pitcairnia, occurring in Mexico, Central America, West Indies and throughout much of South America, with the highest species richness in the Andean region. In Brazil about 54 species are recorded, of which 38 are endemic. These taxa are distributed mainly in three Brazilian domais: Atlantic Rainforest, Amazon and Cerrado. The present study aims to present a phylogenetic hypothesis, based on characters from external and internal morphology, in which will be tested the monophyly of the genera and of its subgenus, still intends to clarify the phylogenetic relationship between the species recorded in the three Brazilian domains. The analysis produced 959 equally parsimonious trees with 903 steps, 0.175 of consistency index and 0.825 of retention index. The results corroborates Pitcairnia s.l. as monophyletic, supported by the presence of phloem fibers and stomatal apparatus positioned at the same level as the epidermal cells as not homoplastic synapomorphies, besides five homoplastic synapomorphies. Moreover Pitcairnia subg. Pepinia and Pitcairnia subg. Pitcairnia is not a natural group, and the presence of winged seed, its main feature used for the segregation of the two subgenres, a character that appeared many times in the evolution of the Pitcairnia s.l. The occupation of Brazilian domains, chiefly the Atlantic Rainforest and Cerrado, occurred in various ways without a single colonization event. The work also enabled the description of Pitcairnia frequens, a new species endemic to the Morro dos Seis Lagos (AM), and the collaboration in Bromeliaceae in the species list of flora of Brazil.

Keywords:—cladistic analysis, parsimony, monocots, Poales, neotropical region, anatomy.

Pages: 94