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Full-Text Articles in Life Sciences
Haplopappus 2: Reality!, M. A. Lane, Ronald L. Hartman, Gregory K. Brown
Haplopappus 2: Reality!, M. A. Lane, Ronald L. Hartman, Gregory K. Brown
Gregory K Brown
Meeting abstract of “Haplopappus 2: Reality!“ in American Journal of Botany, presented at the Annual Meetings of the Botanical Society of America.
Cladistic Relationships Of Aechmea (Bromeliaceae, Bromelioideae) And Allied Genera, A.P.G. De Faria, T. Wendt, Gregory K. Brown
Cladistic Relationships Of Aechmea (Bromeliaceae, Bromelioideae) And Allied Genera, A.P.G. De Faria, T. Wendt, Gregory K. Brown
Gregory K Brown
Aechmea (ca. 220 species) is the largest and most diverse genus in Bromelioideae (Bromeliaceae), and several dissimilar generic concepts and infrageneric classifications have been proposed, frequently involving other closely related Bromelioideae. A morphology-based phylogenetic analysis using parsimony was conducted with 86 taxa, including 52 Aechmea (7 of the 8 recognized subgenera represented) and 34 exemplars from 9 closely related genera as the ingroup. Two species of Cryptanthus were included as the outgroup. The main objectives were to assess the validity of the major infrageneric classification systems proposed for Aechmea and to elucidate the phylogenetic position of Aechmea and putatively related …
Examination Of Subfamilial Phylogeny In Bromeliaceae Using Comparative Sequencing Of The Plastid Locus Ndhf, R. G. Terry, Gregory K. Brown, R. G. Olmstead
Examination Of Subfamilial Phylogeny In Bromeliaceae Using Comparative Sequencing Of The Plastid Locus Ndhf, R. G. Terry, Gregory K. Brown, R. G. Olmstead
Gregory K Brown
Parsimony analysis of 31 sequences of the chloroplast locus ndhF was used to address questions of subfamilial phylogeny in Bromeliaceae. Results presented here are congruent with those from chloroplast DNA restriction site analysis in recognizing a clade containing Bromelioideae and Pitcairnioideae, and in resolving Tillandsioideae near the base of the family. Placements of several taxonomically difficult genera (e.g., Glomeropitcairnia and Navia) corroborate those of traditional treatments; however, these data suggest that Brocchinia (Pitcairnioideae) is the sister group to the remainder of Bromeliaceae. Further evidence for the paraphyly of Pitcairnioideae includes the resolution of Puya as the sister group to Bromelioideae. …
Plicate Staminal Filaments In Tillandsia Subgenus Anoplophytum (Bromeliaceae), T. M. Evans, Gregory K. Brown
Plicate Staminal Filaments In Tillandsia Subgenus Anoplophytum (Bromeliaceae), T. M. Evans, Gregory K. Brown
Gregory K Brown
Plication of stamina!filaments is an important diagnostic character for Tillandsia subgenus Anoplophytum (ca. 45 species). The monophyletic integrity of subgenus Anoplophytum has recently been questioned, and we conducted an anatomical investigation of plicate stamina! filaments to better characterize this putative synapomorphy. Developmental studies show that the filament plications, or folds, become visible during or soon after anthesis. Serial sections of preplication filaments and filaments in sequential stages of plication were prepared and observed with light microscopy. A uniform sequence of parenchyma cell collapse begins three to four cell layers out from the vascular bundle and proceeds centrifugally to the epidermis. …
Haplopappus I : Hall's Illusion, Ronald L. Hartman, M. A. Lane, Gregory K. Brown
Haplopappus I : Hall's Illusion, Ronald L. Hartman, M. A. Lane, Gregory K. Brown
Gregory K Brown
Meeting abstract of “Haplopappus-I : Hall Illusion“ in American Journal of Botany, presented at the Annual Meetings of the Botanical Society of America.
Cladistic Tests Of Hypotheses Concerning Evolution Of Xerophytes And Mesophytes Within Tillandsia Subg Phytarrhiza (Bromeliaceae), A. J. Gilmartin, Gregory K. Brown
Cladistic Tests Of Hypotheses Concerning Evolution Of Xerophytes And Mesophytes Within Tillandsia Subg Phytarrhiza (Bromeliaceae), A. J. Gilmartin, Gregory K. Brown
Gregory K Brown
Tillandsia L. Subg. Phytarrhiza (Visiani) Baker (Bromeliaceae) is a distinctive group of about 35 epiphytic species. These exhibit a range of habits from xeric to mesic. The evolutionary relationships of the contrasting adaptations need to be established here as well as in the subfamily as a whole. Relations between the subgenus and other tillandsioids are problematical and phylogenetic reconstruction of its member-species would be facilitated by identification of Phytarrhiza's relative (sister taxon) sharing the same most recent common ancestor with Phytarrhiza. This paper examines the two most likely sister taxa, Subg. Pseudo-Catopsis Baker and Subg. Diaphoranthema (Beer) Baker. Diaphoranthema is …
Morphological Variation Of Some Floral Features Of The Subfamily Pitcairnioideae (Bromeliaceae) And Their Significance In Pollination Biology, G. S. Varadarajan, Gregory K. Brown
Morphological Variation Of Some Floral Features Of The Subfamily Pitcairnioideae (Bromeliaceae) And Their Significance In Pollination Biology, G. S. Varadarajan, Gregory K. Brown
Gregory K Brown
Scanning electron and light microscopy observations of wet-preserved flowers of Bromeliaceae subfamily Pitcaimioideae yield new information on the stigma, petal scales, and septal nectaries. Variations of the stigma types are evident among several genera. The gross structural features of the stigma do not indicate definite pollination trends, but the shape of the lobes and papillae indicate a few specific modes. In pitcaimioid genera, petal scales, when functional, may aid in pollination by accumulating the nectar secreted from the ovary, thus facilitating its availability to the pollinator. Nectaries associated with the gynoecia usually display tripartite channels in the ovary septa. Some …