Publications by authors named "Benjamin M Torke"

is the most representative genus of the Pantepui woody flora and is among the groups with the greatest endemism in the local flora. The genus has 28 currently recognized species in tropical America, 26 of them endemic to the Pantepui. Here we describe from the summit of Mount Ayanganna tepui in Guyana, providing a morphological description, illustrations, distribution maps, characterization of micromorphology under scanning electron microscopy and leaf venation, comments comparing the new species with closely related species, and a key for the identification of the species of occurring in Guyana.

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Article Synopsis
  • A comprehensive molecular phylogeny of the Pithecellobium clade within the subfamily Caesalpinioideae is presented, covering five genera and 33 species from the southern U.S. to northeastern South America.
  • Researchers aimed to test the monophyly of this group and its genera while uncovering their sister group relationships through an analysis of nuclear ribosomal DNA sequences.
  • The findings support the monophyly of the Pithecellobium clade and confirm the monophyletic status of some genera, while discovering that others are non-monophyletic, leading to their reclassification and the establishment of two new genera.
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The papilionoid legume genus Ormosia (Fabaceae) comprises about 150 species of trees and exhibits a striking disjunct geographical distribution between the New World- and Asian and Australasian wet tropics and subtropics. Modern classifications of Ormosia are not grounded on a well-substantiated phylogenetic hypothesis and have been limited to just portions of the geographical range of the genus. The lack of an evolutionarily-based foundation for systematic studies has hindered taxonomic work on the genus and prevented the testing of biogeographical hypotheses related to the origin of the Old World/New World disjunction and the individual dispersal histories within both areas.

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We investigate patterns of historical assembly of tree communities across Amazonia using a newly developed phylogeny for the species-rich neotropical tree genus We compare our results with those for three other ecologically important, diverse, and abundant Amazonian tree lineages, , Protieae, and Our analyses using phylogenetic diversity metrics demonstrate a clear lack of geographic phylogenetic structure, and show that local communities of and regional communities of all four lineages are assembled by dispersal across Amazonia. The importance of dispersal in the biogeography of and other tree genera in Amazonian and Guianan rain forests suggests that speciation is not driven by vicariance, and that allopatric isolation following dispersal may be involved in the speciation process. A clear implication of these results is that over evolutionary timescales, the metacommunity for any local or regional tree community in the Amazon is the entire Amazon basin.

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The papilionoid legume tribe Brongniartieae comprises a collection of 15 genera with disparate morphologies that were previously positioned in at least four remotely related tribes. The Brongniartieae displays a wide geographical disjunction between Australia and the New World and previous phylogenetic studies had provided conflicting results about the relationships between the American and Australian genera. We carry out phylogenetic analyses of (1) a plastid matK dataset extensively sampled across legumes to solve the enigmatic relationship of the Cuban-endemic monospecific genus Behaimia; and (2) multilocus datasets with focus on all genera ever referred to Brongniartieae.

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A comprehensively sampled reassessment of the molecular phylogeny of the genistoid legumes questions the traditional placement of Haplormosia, an African monotypic genus traditionally classified within tribe Sophoreae close to the Asian-American geographically disjunct genus Ormosia. Plastid matK sequences placed Haplormosia as sister to the American-Australian tribe Brongniartieae. Despite a superficial resemblance between Haplormosia and Ormosia, a re-examination of the morphology of Haplormosia corroborates the new phylogenetic result.

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