Taxonomic implications of pollen exine morphology in infrageneric classification ofScutellaria(Lamiaceae)

ABSTRACTThe yam genus Dioscorea comprises circa 650 species of tropical vines with starch rich tubers, usefull as an energy source and often containing secondary metabolites. The Neotropical Region holds the highest diversity of species and morphology of yams. We generated a time-calibrated tree for Dioscorea using, for the first time, a dense sampling of Neotropical species (64 sp., 20% of all Neotropical sp. and 22 sections) to trace the biogeography of these plants in this region. Four origins of Dioscorea in the neotropics were estimated since the Eocene. The two most diverse lineages originated between the Eocene and Oligocene, respectively in the Southern Andes and eastern South America. Both lineages occupied the South American ‘Dry Diagonal’ after the Miocene, but New World II clade remained associated with forest habitats. Several exchanges between Dry Diagonal and adjacent forested biomes occurred, corroborating the interchange between these vegetation types. Dispersals to Central America occurred before the closure of the Panama Isthmus. We highlight two important events of long distance dispersal, the colonization of Central American before the closure of Isthmus of Panama and the dispersal of D. antaly lineage to Madagascar. In addition, our phylogenetic tree evidenced the unnatural nature of the classical infrageneric classification of Dioscorea. The taxonomic implications of our results are also discussed.

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Molecular Phylogeny of Axonopus (Poaceae, Panicoideae, Paspaleae): Monophyly, Synapomorphies, and Taxonomic Implications for Infrageneric Classification and Species Complexes

Annals of the Missouri Botanical Garden ◽

10.3417/2020451 ◽

2020 ◽

Vol 105 (4) ◽

pp. 459-480

Author(s):

Carolina Delfini ◽

Juan M. Acosta ◽

Vinicius Castro Souza ◽

Fernando O. Zuloaga

Keyword(s):

Phylogenetic Analyses ◽

Morphological Characters ◽

Character State ◽

Infrageneric Classification ◽

Ancestral Character State ◽

Limited Sampling ◽

Species Complexes ◽

External Transcribed Spacer ◽

Taxonomic Implications

Axonopus P. Beauv. comprises nearly 90, mostly New World, species characterized by having spikelets with the inverse position (i.e., the backs of the upper glume and the upper lemma turned away from the rachis). The genus has been divided into four sections, five series, and three subseries, based exclusively on morphological features. Previous phylogenetic analyses based on a limited sampling of species showed Axonopus to be a monophyletic genus. In this study we increased the number of species sampled (46 species in the combined tree) and sequenced four DNA regions (external transcribed spacer [ETS], internal transcribed spacer [ITS], trnL-F, and ndhF). We tested the monophyly of Axonopus and its traditional infrageneric categories using parsimony, likelihood, and Bayesian inference. Additionally, we performed ancestral character state reconstructions of 45 morphological characters to infer autapomorphies of the species and synapomorphies for the genus and clades. Our findings confirmed Axonopus as a monophyletic genus only when Centrochloa Swallen and Ophiochloa Filg., Davidse & Zuloaga are included within it. Our analyses also showed that, with the exception of section Lappagopsis, infrageneric categories from previous classifications of the genus are artificial. Twenty-one morphological character states were identified as potential autapomorphies; two were reconstructed as potential synapomorphies for Axonopus, whereas 12 were reconstructed as potential synapomorphies for specific clades within the genus. Further molecular analyses, including sequencing of unlinked nuclear genes, are needed in order to reach a robust phylogenetic classification of the genus.

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Trichome micromorphology of the Chinese-Himalayan genus Colquhounia (Lamiaceae), with emphasis on taxonomic implications

Biologia ◽

10.2478/s11756-012-0076-z ◽

2012 ◽

Vol 67 (5) ◽

Cited By ~ 11

Author(s):

Guo-Xiong Hu ◽

Teodora Balangcod ◽

Chun-Lei Xiang

Keyword(s):

Glandular Trichomes ◽

Morphological Diversity ◽

Species Relationships ◽

Key To Species ◽

Infrageneric Classification ◽

C Elegans ◽

Taxonomic Implications ◽

Trichome Morphology ◽

Insight Into ◽

Number Of Cells

AbstractTrichome micromorphology of leaves and young stems of nine taxa (including four varieties) of Colquhounia were examined using light and scanning microscopy. Two basic types of trichomes were recognized: eglandular and glandular. Eglandular trichomes are subdivided into simple and branched trichomes. Based on the number of cells and trichome configuration, simple eglandular trichomes are further divided into four forms: unicellular, two-celled, three-celled and more than three-celled trichomes. Based on branching configuration, the branched eglandular trichomes can be separated into three forms: biramous, stellate and dendroid. Glandular trichomes can be divided into two subtypes: capitate and peltate glandular trichomes. Results from this study of morphological diversity of trichomes within Colquhounia lend insight into infrageneric classification and species relationships. Based on the presence of branched trichomes in C. elegans, this species should be transferred from Colquhounia sect. Simplicipili to sect. Colquhounia. We provide a taxonomic key to species of Chinese Colquhounia based on trichome morphology and other important morphological traits.

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Paepalanthus fabianeae (Eriocaulaceae): A New Microendemic Species from a Morphologically Coherent Clade

Systematic Botany ◽

10.1600/036364420x16033963649318 ◽

2020 ◽

Vol 45 (4) ◽

pp. 794-801

Author(s):

Caroline Oliveira Andrino ◽

Marcelo Fragomeni Simon ◽

Jair Eustáquio Quintino Faria ◽

André Luiz da Costa Moreira ◽

Paulo Takeo Sano

Keyword(s):

New Species ◽

Iucn Red List ◽

Phylogenetic Position ◽

Similar Species ◽

Infrageneric Classification ◽

Espinhaço Range ◽

Nuclear Its ◽

Two Populations

Abstract—We describe and illustrate Paepalanthus fabianeae, a new species of Eriocaulaceae from the central portion of the Espinhaço Range in Minas Gerais, Brazil. Previous phylogenetic evidence based on analyses of nuclear (ITS and ETS) and plastid (trnL-trnF and psba-trnH) sequences revealed P. fabianeae as belonging to a strongly supported and morphologically coherent clade containing five other species, all of them microendemic, restricted to the Espinhaço range. Due to the infrageneric classification of Paepalanthus being highly artificial, we preferred not assigning P. fabianeae to any infrageneric group. Paepalanthus fabianeae is known from two populations growing in campos rupestres (highland rocky fields) in the meridional Espinhaço Range. The species is characterized by pseudodichotomously branched stems, small, linear, recurved, and reflexed leaves, urceolate capitula, and bifid stigmas. Illustrations, photos, the phylogenetic position, and a detailed description, as well as comments on habitat, morphology, and affinities with similar species are provided. The restricted area of occurrence allied with threats to the quality of the habitat, mainly due to quartzite mining, justifies the preliminary classification of the new species in the Critically Endangered (CR) category using the guidelines and criteria of the IUCN Red List.

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Infrageneric classification of Agave L. (Asparagaceae: Agavoideae / Agavaceae): a nomenclatural assessment and updated classification at the rank of section, with new combinations

Bradleya ◽

10.25223/brad.n37.2019.a22 ◽

2019 ◽

Vol 2019 (37) ◽

pp. 240 ◽

Cited By ~ 3

Author(s):

Joachim Thiede ◽

Gideon F. Smith ◽

Urs Eggli

Keyword(s):

New Combinations ◽

Infrageneric Classification

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Distribution of Isoprenoid Quinone Structural Types in Bacteria and Their Taxonomic Implications

Microbiological Reviews ◽

10.1128/mr.45.3.481-481.1981 ◽

1981 ◽

Vol 45 (3) ◽

pp. 481-481

Keyword(s):

Isoprenoid Quinone ◽

Structural Types ◽

Taxonomic Implications

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Peptidoglycan Types of Bacterial Cell Walls and Their Taxonomic Implications

Bacteriological Reviews ◽

10.1128/mmbr.37.2.258-258.1973 ◽

1973 ◽

Vol 37 (2) ◽

pp. 258-258 ◽

Cited By ~ 3

Keyword(s):

Bacterial Cell ◽

Cell Walls ◽

Taxonomic Implications ◽

Bacterial Cell Walls

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Systematics and evolution of Lentibulariaceae: I. Pinguicula

10.1093/oso/9780198779841.003.0006 ◽

2018 ◽

Cited By ~ 2

Author(s):

Andreas Fleischmann ◽

Aymeric Roccia

Keyword(s):

Phylogenetic Tree ◽

Evolutionary History ◽

Infrageneric Classification ◽

Distribution Maps

Systematics and evolution of Pinguicula (butterworts) (Lentibulariaceae) are treated. Vegetative and generative morphology of the genus are illustrated and interpreted in the light of available phylogenetic evidence. A new infrageneric classification is proposed for Pinguicula; a simplified phylogenetic tree and detailed distribution maps are provided. Evolutionary history and phylobiogeography are briefly discussed together with the habitats, ecology, and conservation of the genus.

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