39 research outputs found
GARRYA OVATA BENTH. SUBSP. GOLDMANII (WOOTON & STANDL.) DAHLING (GARRYACEAE) AND BESCHORNERIA CALCICOLA GARCÍA-MENDOZA (AGAVACEAE): TWO NEW REPORTS FROM VERACRUZ, MEXICO.
New reports of Garrya ovata ssp. goldmanii(Wooton & Standl.) Dahling and Beschorneriacalcicola García-Mendoza are presented forthe state of Veracruz, Mexico. Both taxa werefound on karstic hills in the arid zone ofVeracruz near Tenextepec, Perote. Garryaovata ssp. goldmanii is a small shrub measuringup to 1.5 m tall, which contrasts considerablywith G. laurifolia Benth. ssp. laurifolia and G.laurifolia Benth. ssp. macrophylla alreadyregistered for Veracruz. These are shrubs ortrees from 2 to 10 m tall. Beschorneriacalcicola is a small rosettiform plant measuringup to 60 cm tall which contrasts with B.yuccoides K. Koch ssp. dekosteriana (K.Koch) García-Mendoza of Veracruz, which is alarge plant from 1 to 2.5 m tall, with large wideleaves.Se encontraron como nuevos registros paraVeracruz Garrya ovata ssp. goldmanii(Wooton & Standl.) Dahling y Beschorneriacalcicola García-Mendoza, ambas seencontraron en los cerros calizos de la zonaárida veracruzana, en los alrededores deTenextepec, Perote. Garrya ovata ssp.goldmanii es un arbusto pequeño que midehasta 1.5 m de alto, contrastandoconsiderablemente con G. laurifolia Benth. ssp.laurifolia y G. laurifolia Benth. ssp.macrophylla ya registradas de Veracruz, lascuales son arbustos o árboles de 2 a 10 m dealto. De la misma forma Beschorneriacalcicola es una planta pequeña, rosetiformeque mide hasta 60 cm de alto, en contraste conB. yuccoides K. Koch ssp. dekosteriana(K.Koch) García-Mendoza conocida paraVeracruz, que es una planta grande de 1- 2.5 mde alto, con hojas grandes y anchas
UNA NUEVA ESPECIE DE STROMANTHE (MARANTACEAE) DE VERACRUZ, MÉXICO.
Stromanthe popolucana is described as a newspecies of Marantaceae from southernVeracruz, Mexico. It appears to be related toStromanthe jacquinii (Roem. & Schult.)Kennedy & Nicolson and Stromantheramosissima L., from both of which it differsin its smaller petioles, leaves, and fruits, andits much longer peduncles and cymes. It is aspecies of evergreen tropical rain forest, witha restricted distribution on the volcano of SanMartín Pajapan. This species is consideredendangered due to the changes in land use inthe Los Tuxtlas region.Se describe como especie nueva a Stromanthepopolucana (Marantaceae) del sur del estadode Veracruz. Se encuentra relacionada conStromanthe jacquinii (Roem. & Schult.)Kennedy & Nicolson y Stromantheramosissima L. de las cuales difiere porpresentar pecíolos, hojas y frutos máspequeños y el pedúnculo de la címula máslargo. Es una especie de selva altaperennifolia, que presenta una distribuciónrestringida al Volcán de San Martín Pajapan,Veracruz. Esta especie se encuentraamenazada de extinción por el cambio de usodel suelo que se está dando en la región deLos Tuxtlas
A reassessment of the Ceratozamia miqueliana species complex (Zamiaceae) of southeastern Mexico, with comments on species relationships
A reassessment of the Ceratozamia miqueliana species complex (Zamiaceae) of southeastern Mexico, with comments on species relationships Abstract The Ceratozamia miqueliana species complex has been revised from a morphological, anatomical and biogeographical perspective. The complex consists of five closely related species, one of which is new, C. santillanii sp. nov., and is described and illustrated from the northern highlands of Chiapas. The five species, although not sympatric, occur in the 'Arc' Pleistocene floristic refuge that covers southern Mexico, including northern Oaxaca and Chiapas, as well as southern Tabasco and Veracruz. The five species are characterised by oblong, oblanceolate to widely oblanceolate leaflets with decumbent or erect megastrobili when ripe. The species complex consists of C. becerrae Pérez-Farr., Vovides & Schutzman C. euryphyllidia Vázq.Torres, Sabato & D.W. Stev., C. miqueliana H. Wendl., C. zoquorum Pérez-Farr., Vovides & Iglesias and the new species which is related to C. zoquorum, but differs from these in leaf, male and female cone growth habit, as well as inter-leaflet distance. Discriminant analysis using the five species with 14 variables showed significant differences (Wilks λ test, P < 0.01) for four functions among the five species. Mahalanobis distances were also highly significant among the five species (P < 0.01). Ceratozamia euryphyllidia and C. becerrae were the most distant, whereas C. zoquorum and C. becerrae were closest
Molecular and Morphological Phylogenetic Analyses of New World Cycad Beetles: What They Reveal about Cycad Evolution in the New World
Two major lineages of beetles inhabit cycad cones in the New World: weevils (Curculionoidea) in the subtribe Allocorynina, including the genera Notorhopalotria Tang and O’Brien, Parallocorynus Voss, Protocorynus O’Brien and Tang and Rhopalotria Chevrolat, and beetles in the family Erotylidae, including the genus Pharaxonotha Reitter. Analysis of the 16S ribosomal RNA (rRNA) mitochondrial gene as well as cladistic analysis of morphological characters of the weevils indicate four major radiations, with a probable origin on the cycad genus Dioon Lindl. and comparatively recent host shifts onto Zamia L. Analysis of the 16S rRNA gene for erotylid beetles indicates that an undescribed genus restricted to New World Ceratozamia Brongn. is the most early-diverging clade, and this lineage is sister to a large radiation of the genus Pharaxonotha onto Zamia, with apparent host shifts onto Dioon and Ceratozamia. Analysis of beetles are in accord with current models of continental drift in the Caribbean basin, support some proposed species groupings of cycads, but not others, and suggest that pollinator type may impact population genetic structure in their host cycads
A modification to the SCAR (Sequence Characterized Amplified Region) method provides phylogenetic insights within Ceratozamia (Zamiaceae) Una modificación al método SCAR (Sequence Characterized Amplified Region) aporta entendimiento filogenético en Ceratozamia (Zamiaceae)
Phylogenetic relationships among closely related plant species are still problematic. DNA intergenic regions often are insufficiently variable to provide desired resolution or support. In this study, a modification to the Sequence Characterized Amplified Region (SCAR) method was used to find polymorphic loci for phylogenetic analyses within Ceratozamia. RAPD markers were first used to detect variation in 5 species. Then, equal length fragments found in 2 or more species were excised from the gel, purified and digested with frequent cutter restriction enzymes for isolating both ends, which have the same primer site. Digested fragments were sequenced with the RAPD primer. Variable sequences were used to design specific primers for amplifying and sequencing in all species for phylogenetic analyses. Our results confirmed the previously known high genome sequence resemblance within this genus that contrasts with its high morphological variation. Only 7 parsimony informative characters were found with this approach. Nonetheless, the Digested-SCAR (D-SCAR) method provided some phylogenetic insights. Four main clades consistent with distribution ranges of the species were detected. The approach presented here was effective to solve some relationships within the genus and can potentially be implemented in other organisms to find polymorphic loci for phylogenetic studies at any taxonomic level.<br>Las relaciones filogenéticas entre especies de plantas cercanamente relacionadas es aún problemático. Las regiones intergénicas del ADN son a menudo insuficientemente variables para proveer los niveles de resolución y soporte deseados. En este estudio, se usó una modificación al método Sequence Characterized Amplified Region (SCAR) para encontrar loci polimórficos para análisis filogenéticos en Ceratozamia. Primero se usaron marcadores RAPD para detectar variación en 5 especies; luego, se cortaron del gel los fragmentos de la misma longitud en 2 o más especies, se purificaron y se digirieron con enzimas de restricción de corte frecuente para aislar las 2 terminaciones que tienen el mismo sitio del oligo. Los fragmentos digeridos se secuenciaron con el oligo usado para los RAPD. Las secuencias variables se usaron para diseñar oligos específicos para amplificar y secuenciar todas las especies para los análisis filogenéticos. Nuestros resultados confirmaron la elevada semejanza del genoma, previamente detectada dentro de este género, que contrasta con su elevada variación morfológica. Sólo 7 caracteres parsimoniosamente informativos se encontraron con esta estrategia. No obstante, el método SCAR-digerido (D-SCAR) aportó entendimiento filogenético adicional. Se detectaron 4 clados principales que son consistentes con el intervalo de distribución de las especies. La estrategia presentada en este trabajo fue efectiva para resolver algunas relaciones dentro del género y potencialmente puede implementarse en otros organismos para encontrar loci polimórficos para estudios filogenéticos a cualquier nivel taxonómico
Números cromosómicos de cuatro especies de Costus (Costaceae), una de Calathea, una de Maranta y una de Stromanthe (Marantaceae)
Chromosome counts of the following species were done: Costus pictus, C. scaber and C. pulverulentus all have 2n = 18; Costus dirzoi 2n = 27, 28; Calathea ovandensis 2n = 25; Maranta gibba 2n = 40 and Stromanthe macrochlamys 2n = ca. 60, ca. 63. Observations on Costus lead us to consider the probable existence of a polyploid series, with the recently described C. dirzoi being triploid.Se hicieron recuentos cromosómicos de las siguientes especies: Costus pictus, C. scaber y C. pulverulentus tienen todos 2n = 18; Costus dirzoi 2n = 27, 28; Calathea ovandensis 2n = 25; Maranta gibba 2n = 40 y Stromanthe macrochlamys 2n = ca. 60, ca. 63. Nuestras observaciones sobre Costus hacen pensar en la probable existencia de una serie poliploide, siendo triploide la recién descrita C. dirzoi
A modification to the SCAR (Sequence Characterized Amplified Region) method provides phylogenetic insights within Ceratozamia (Zamiaceae)
CERATOZAMIA MICROSTROBILA (ZAMIACEAE), A NEW SPECIES FROM SAN LUIS POTOS\ucd, MEXICO
Volume: 30Start Page: 39End Page: 4