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Steph B. J. Menken - One of the best experts on this subject based on the ideXlab platform.

  • Molecular phylogeny of the small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) in the palaearctic.
    PloS one, 2010
    Co-Authors: Hubert Turner, Niek Lieshout, Wil Van Ginkel, Steph B. J. Menken
    Abstract:

    Background The small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) contains 76 species that are specialist feeders on hosts from Celastraceae, Rosaceae, Salicaceae, and several other plant families. The genus is a model for studies in the evolution of phytophagous insects and their host-plant associations. Here, we reconstruct the phylogeny to provide a solid framework for these studies, and to obtain insight into the history of host-plant use and the biogeography of the genus.

  • Molecular phylogeny of the small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) in the palaearctic.
    Public Library of Science (PLoS), 2010
    Co-Authors: Hubert Turner, Niek Lieshout, Wil Van Ginkel, Steph B. J. Menken
    Abstract:

    The small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) contains 76 species that are specialist feeders on hosts from Celastraceae, Rosaceae, Salicaceae, and several other plant families. The genus is a model for studies in the evolution of phytophagous insects and their host-plant associations. Here, we reconstruct the phylogeny to provide a solid framework for these studies, and to obtain insight into the history of host-plant use and the biogeography of the genus.DNA sequences from an internal transcribed spacer region (ITS-1) and from the 16S rDNA (16S) and cytochrome oxidase (COII) mitochondrial genes were collected from 20-23 (depending on gene) species and two outgroup taxa to reconstruct the phylogeny of the Palaearctic members of this genus. Sequences were analysed using three different phylogenetic methods (parsimony, likelihood, and Bayesian inference).Roughly the same patterns are retrieved irrespective of the method used, and they are similar among the three genes. Monophyly is well supported for a clade consisting of the Japanese (but not the Dutch) population of Yponomeuta sedellus and Y. yanagawanus, a Y. kanaiellus-polystictus clade, and a Rosaceae-feeding, western Palaearctic clade (Y. cagnagellus-irrorellus clade). Within these clades, relationships are less well supported, and the patterns between the different gene trees are not so similar. The position of the remaining taxa is also variable among the gene trees and rather weakly supported. The phylogenetic information was used to elucidate patterns of biogeography and resource use. In the Palaearctic, the genus most likely originated in the Far East, feeding on Celastraceae, dispersing to the West concomitant with a shift to Rosaceae and further to Salicaceae. The association of Y. cagnagellus with Euonymus europaeus (Celastraceae), however, is a reversal. The only oligophagous species, Y. padellus, belongs to the derived western Palaearctic clade, evidence that specialisation is reversible

  • Olfactory receptors on the maxillary palps of small ermine moth larvae: evolutionary history of benzaldehyde sensitivity
    Journal of Comparative Physiology A, 2007
    Co-Authors: Peter Roessingh, Steph B. J. Menken
    Abstract:

    In lepidopterous larvae the maxillary palps contain a large portion of the sensory equipment of the insect. Yet, knowledge about the sensitivity of these cells is limited. In this paper a morphological, behavioral, and electrophysiological investigation of the maxillary palps of Yponomeuta cagnagellus (Lepidoptera: Yponomeutidae) is presented. In addition to thermoreceptors, CO_2 receptors, and gustatory receptors, evidence is reported for the existence of two groups of receptor cells sensitive to plant volatiles. Cells that are mainly sensitive to ( E )-2-hexenal and hexanal or to ( Z )-3-hexen-1-ol and 1-hexanol were found. Interestingly, a high sensitivity for benzaldehyde was also found. This compound is not known to be present in Euonymus europaeus , the host plant of the monophagous Yponomeuta cagnagellus , but it is a prominent compound in Rosaceae, the presumed hosts of the ancestors of Y. cagnagellus . To elucidate the evolutionary history of this sensitivity, and its possible role in host shifts, feeding responses of three Yponomeuta species to benzaldehyde were investigated. The results confirm the hypothesis that the sensitivity to benzaldehyde evolved during the ancestral shift from Celastraceae to Rosaceae and can be considered an evolutionary relict, retained in the recently backshifted Celastraceae-specialist Y. cagnagellus .

Mark P. Simmons - One of the best experts on this subject based on the ideXlab platform.

  • Employing Two‐stage Derivatisation and GC–MS to Assay for Cathine and Related Stimulant Alkaloids across the Celastraceae
    Phytochemical Analysis, 2017
    Co-Authors: Luke R Tembrock, Mark P. Simmons, Corey D. Broeckling, Adam L. Heuberger, Frank R. Stermitz, Jessica M. Uvarov
    Abstract:

    Introduction Catha edulis (qat, khat, mirra) is a woody plant species that is grown and consumed in East Africa and Yemen for its stimulant alkaloids cathinone, cathine and norephedrine. Two Celastraceae species, in addition to qat, have been noted for their stimulant properties in ethnobotanical literature. Recent phylogenetic reconstructions place four genera in a clade sister to Catha edulis, and these genera are primary candidates to search for cathine and related alkaloids. Objective Determine if cathine or related alkaloids are present in species of Celastraceae other than Catha edulis. Methods Leaf samples from 43 Celastraceae species were extracted in water followed by basification of the aqueous extract and partitioning with methyl-t-butyl ether to provide an alkaloid-enriched fraction. The extract was derivatised in a two-stage process and analysed using GC–MS for the presence of cathine. Related alkaloids and other metabolites in this alkaloid-enriched fraction were tentatively identified. Results Cathinone, cathine and norephedrine were not detected in any of the 43 Celastraceae species assayed other than Catha edulis. However, the phenylalanine- or tyrosine-derived alkaloid phenylethylamine was identified in five species. Nine species were found to be enriched for numerous sterol- and terpene-like compounds. Conclusion These results indicate that cathine is unique to Catha edulis, and not the compound responsible for the stimulant properties reported in related Celastraceae species. Copyright © 2017 John Wiley & Sons, Ltd.

  • employing two stage derivatisation and gc ms to assay for cathine and related stimulant alkaloids across the Celastraceae
    Phytochemical Analysis, 2017
    Co-Authors: Luke R Tembrock, Mark P. Simmons, Corey D. Broeckling, Adam L. Heuberger, Frank R. Stermitz, Jessica M. Uvarov
    Abstract:

    Introduction Catha edulis (qat, khat, mirra) is a woody plant species that is grown and consumed in East Africa and Yemen for its stimulant alkaloids cathinone, cathine and norephedrine. Two Celastraceae species, in addition to qat, have been noted for their stimulant properties in ethnobotanical literature. Recent phylogenetic reconstructions place four genera in a clade sister to Catha edulis, and these genera are primary candidates to search for cathine and related alkaloids. Objective Determine if cathine or related alkaloids are present in species of Celastraceae other than Catha edulis. Methods Leaf samples from 43 Celastraceae species were extracted in water followed by basification of the aqueous extract and partitioning with methyl-t-butyl ether to provide an alkaloid-enriched fraction. The extract was derivatised in a two-stage process and analysed using GC–MS for the presence of cathine. Related alkaloids and other metabolites in this alkaloid-enriched fraction were tentatively identified. Results Cathinone, cathine and norephedrine were not detected in any of the 43 Celastraceae species assayed other than Catha edulis. However, the phenylalanine- or tyrosine-derived alkaloid phenylethylamine was identified in five species. Nine species were found to be enriched for numerous sterol- and terpene-like compounds. Conclusion These results indicate that cathine is unique to Catha edulis, and not the compound responsible for the stimulant properties reported in related Celastraceae species. Copyright © 2017 John Wiley & Sons, Ltd.

  • biogeography of the malagasy Celastraceae multiple independent origins followed by widespread dispersal of genera from madagascar
    Molecular Phylogenetics and Evolution, 2016
    Co-Authors: Christine D Bacon, Mark P. Simmons, Robert H Archer, Liangcheng Zhao, Jacky Andriantiana
    Abstract:

    Of the 97 currently recognized genera of Celastraceae, 19 are native to Madagascar, including six endemics. In this study we conducted the most thorough phylogenetic analysis of Celastraceae yet completed with respect to both character and taxon sampling, and include representatives of five new endemic genera. Fifty-one new accessions, together with 328 previously used accessions of Celastrales, were sampled for morphological characters, two rDNA gene regions, and two plastid gene regions. The endemic Malagasy genera are resolved in two separate lineages-Xenodrys by itself and all other endemic genera in a clade that also includes four lineages inferred to have dispersed from Madagascar: Brexia madagascariensis (Mascarene Islands, coastal Africa), Elaeodendron (West Indies, Africa to New Caledonia), and Pleurostylia (Africa to New Caledonia). Of the 12 extant Malagasy Celastraceae lineages identified, eight are clearly of African origin. The origins of the remaining four lineages are less clear, but reasonable possibilities include America, Eurasia, Africa, southern India, Malesia, and Australia. Based on 95% credible age intervals from fossil-calibrated molecular dating, all 12 extant Malagasy Celastraceae lineages appear to have arisen following dispersal after the separation of Madagascar from other landmasses within the last 70 million years.

  • A New Species of Maytenus (Celastraceae) with Fleshy Fruits from Eastern Brazil, with Notes on the Delimitation of Maytenus
    Systematic Botany, 2014
    Co-Authors: Milton Groppo, Leonardo Biral, Jennifer J. Cappa, Mark P. Simmons, Julio Antonio Lombardi
    Abstract:

    Abstract A new species of Celastraceae, Maytenus megalocarpa, is described and illustrated. The species is known from only a small number of collections from eastern Brazil, in the Atlantic Rainforest of Bahia and Minas Gerais states. It is considered endangered given the rapid deforestation of this biome. The species is readily distinguished from its congeners by its large, tardily dehiscent fruit that does not open by reflexed valves and by the seeds enveloped by thick arils. Given its remarkable fruits and the consequent initial doubt about the generic position of the new species in Celastraceae, a phylogenetic analysis using molecular data from plastid and nuclear rDNA gene regions, together with morphological characters, was performed. The new species was consistently resolved as nested within Maytenus, which itself is paraphyletic. Incongruence between the nuclear and plastid gene regions was identified for Fraunhofera, Maytenus texana, and Plenckia. Future taxonomic changes are necessary to rigorou...

  • phylogeny of Celastraceae subfamilies cassinoideae and tripterygioideae inferred from morphological characters and nuclear and plastid loci
    Systematic Botany, 2012
    Co-Authors: Mark P. Simmons, Jennifer J. Cappa, Christine D Bacon, Miles J Mckenna
    Abstract:

    Abstract The phylogeny of Celastraceae subfamilies Cassinoideae (120 species in 17 genera in both the Old and New World tropics and subtropics) and Tripterygioideae (39 species in seven genera) was inferred using plastid (matK, trnL-F) and nuclear (ITS and 26S rDNA) loci together with morphological characters. Subfamily Cassinoideae include those Celastraceae genera with drupes, berries, or nuts that have one to five locules and one to two seeds per locule, while Tripterygioideae include those genera with one to two seeded samaras that lack arillate seeds. We infer that both subfamilies are grossly polyphyletic groups, with Cassinoideae consisting of ≥ eight separate lineages and Tripterygioideae consisting of ≥ six separate lineages. Crossopetalum, from tropical America, is part of an early derived lineage sister to a taxonomically diverse Austral-Pacific clade. Myginda is not distinct from Crossopetalum. Gyminda + Orthosphenia + Rzedowskia + Schaefferia are a clade that is only distantly related to Cros...

Luc Angenot - One of the best experts on this subject based on the ideXlab platform.

Janete H Y Vilegas - One of the best experts on this subject based on the ideXlab platform.

Hubert Turner - One of the best experts on this subject based on the ideXlab platform.

  • Molecular phylogeny of the small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) in the palaearctic.
    PloS one, 2010
    Co-Authors: Hubert Turner, Niek Lieshout, Wil Van Ginkel, Steph B. J. Menken
    Abstract:

    Background The small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) contains 76 species that are specialist feeders on hosts from Celastraceae, Rosaceae, Salicaceae, and several other plant families. The genus is a model for studies in the evolution of phytophagous insects and their host-plant associations. Here, we reconstruct the phylogeny to provide a solid framework for these studies, and to obtain insight into the history of host-plant use and the biogeography of the genus.

  • Molecular phylogeny of the small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) in the palaearctic.
    Public Library of Science (PLoS), 2010
    Co-Authors: Hubert Turner, Niek Lieshout, Wil Van Ginkel, Steph B. J. Menken
    Abstract:

    The small ermine moth genus Yponomeuta (Lepidoptera, Yponomeutidae) contains 76 species that are specialist feeders on hosts from Celastraceae, Rosaceae, Salicaceae, and several other plant families. The genus is a model for studies in the evolution of phytophagous insects and their host-plant associations. Here, we reconstruct the phylogeny to provide a solid framework for these studies, and to obtain insight into the history of host-plant use and the biogeography of the genus.DNA sequences from an internal transcribed spacer region (ITS-1) and from the 16S rDNA (16S) and cytochrome oxidase (COII) mitochondrial genes were collected from 20-23 (depending on gene) species and two outgroup taxa to reconstruct the phylogeny of the Palaearctic members of this genus. Sequences were analysed using three different phylogenetic methods (parsimony, likelihood, and Bayesian inference).Roughly the same patterns are retrieved irrespective of the method used, and they are similar among the three genes. Monophyly is well supported for a clade consisting of the Japanese (but not the Dutch) population of Yponomeuta sedellus and Y. yanagawanus, a Y. kanaiellus-polystictus clade, and a Rosaceae-feeding, western Palaearctic clade (Y. cagnagellus-irrorellus clade). Within these clades, relationships are less well supported, and the patterns between the different gene trees are not so similar. The position of the remaining taxa is also variable among the gene trees and rather weakly supported. The phylogenetic information was used to elucidate patterns of biogeography and resource use. In the Palaearctic, the genus most likely originated in the Far East, feeding on Celastraceae, dispersing to the West concomitant with a shift to Rosaceae and further to Salicaceae. The association of Y. cagnagellus with Euonymus europaeus (Celastraceae), however, is a reversal. The only oligophagous species, Y. padellus, belongs to the derived western Palaearctic clade, evidence that specialisation is reversible