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Andrea S Vega - One of the best experts on this subject based on the ideXlab platform.
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Taxonomic novelties and synopsis of the genus Digitaria (Poaceae, Panicoideae, Paniceae) in Puerto Rico and the Virgin Islands
Darwiniana nueva serie, 2018Co-Authors: Andrea S Vega, Zulma E. Rúgolo De Agrasar, Franklin S. AxelrodAbstract:The present paper reports 18 taxa of Digitaria in Puerto Rico and the Virgin Islands as a contribution to an ongoing floristic project. Digitaria filiformis var. dolichophylla, D. fragilis, D. sacchariflora, and D. similis constitute new reports. Digitaria ekmanii, D. fuscescens, D. panicea, and Digitaria × umfolozi are excluded taxa. This contribution includes synonymy, iconography, geographic distribution and habitat, vernacular names, specimens examined and a key for the identification of taxa. Digitaria filiformis var. dolichophylla is fully illustrated for the first time.
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phylogeny of Digitaria sections trichachne and trichophorae poaceae panicoideae paniceae a morphological and molecular analysis new circumscription and synopsis
Systematic Botany, 2017Co-Authors: Julia Mariela Lo Medico, Gabriel H Rua, Daniela Sandra Tosto, Zulma Esther Rugolo De Agrasar, Maria Amalia Scataglini, Andrea S VegaAbstract:Abstract The present study provides evidence for taxonomic delimitation of Digitaria sect. Trichachne based on morphological data (micro- and macromorphology) and molecular data. A phylogenetic analysis was performed using 121 morphological characters and ITS sequences of 22 species and one variety of Digitaria plus three outgroups. In all topologies (based on morphological, molecular, and combined data) Digitaria sect. Trichophorae was non-monophyletic and nested within D. sect. Trichachne. Digitaria sect. Trichophorae is thus synonymized under D. sect. Trichachne and the circumscription of D. sect. Trichachne is emended. Diagnostic morphological characters related to spikelet structure are described and documented with SEM. A key to taxa belonging to D. sect. Trichachne is provided, as well as a synopsis including synonymy, iconography, geographical distribution, and ecology. The neotype of Trichachne sacchariflora Nees is herein designated. Complete illustrations of Digitaria eggersii, D. hitchcockii, ...
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Lectotypifications in taxa of the genera Calamagrostis, Deyeuxia, and Digitaria (Poaceae) Lectotipificaciones en taxones de los géneros Calamagrostis, Deyeuxia y Digitaria (Poaceae)
2013Co-Authors: Andrea S Vega, E Zulma, Cátedra De Botánica AgrícolaAbstract:ABSTRACT Twenty one taxa of the genera Calamagrostis Adans., Deyeuxia Clarion ex P. Beauv., and Digitaria Haller emend. A. S. Vega & Rugolo are herein lectotypified on the basis of specimens and fragments obtained from original material deposited at Berlin-Dahlem (B) and La Molina (MOL) herbaria. K EYWORDS : Calamagrostis , Deyeuxia , Digitaria , lectotypes, Poaceae. RESUMEN Se designan aqui los lectotipos de 21 taxones pertenecientes a los generos Calamagrostis Adans., Deyeuxia Clarion ex P. Beauv. y Digitaria Haller emend. A. S. Vega & Rugolo sobre la base de especimenes y fragmentos obtenidos de material original depositado en los herbarios Berlin-Dahlem (B) y La Molina (MOL). P ALABRAS CLAVE : Calamagrostis , Deyeuxia , Digitaria , lectotipos, Poaceae. INTRODUCTION On the basis of a previous catalogue of 310 types proceeding from Berlin-Dahlem (B), deposited at Gaspar Xuarez Herbarium (BAA) [Nicora and Rugolo de Agrasar, 1998] and the whole Catalogue of Poaceae types at BAA (Vega, in press), we selected a list of taxa belonging to genera of our knowledge that remains without lectotypification. Lectotypes are here designated for the following 21 taxa of
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a new species of tarigidia poaceae panicoideae paniceae from puerto rico and additional evidence for a hybrid origin of the genus
Systematic Botany, 2010Co-Authors: Andrea S Vega, Zulma Rugolo E De Agrasar, Franklin AxelrodAbstract:A new species of Tarigidia from Puerto Rico is described and illustrated. Additional micromorphological characters of the inflorescence and spikelets are included. This species constitutes the first report of the genus Tarigidia in the New World. Tarigidia axelrodii grows together with Anthephora hermaphrodita and Digitaria bicornis, showing intermediate characters. This species gives additional evidence to support Loxton's hypothesis that Tarigidia is derived from hybridization between Anthephora and Digitaria and also supports the phylogenetic hypothesis showing close relationships between Anthephora and Digitaria.
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a morphology based cladistic analysis of Digitaria poaceae panicoideae paniceae
Systematic Botany, 2009Co-Authors: Andrea S Vega, Gabriel H Rua, Liliana T Fabbri, Zulma Rugolo E De AgrasarAbstract:A phylogenetic analysis was performed on 67 species of Digitaria belonging to four subgenera and 26 of the 32 sections recognized in Henrard's monograph. The analysis was based on 113 discrete and six continuous morphological characters. In the resulting topologies the genus Digitaria was monophyletic. In spite of the low support for most groupings, several clades were recovered. The subdivision of Digitaria in the four subgenera proposed by Henrard was not supported since the large subgenus Digitaria appears as a paraphyletic assemblage within which the other three subgenera are nested. Nevertheless, the monophyly of some of Henrard's sections was supported. This is the first approach to the phylogeny of Digitaria.
Carmen Salas - One of the best experts on this subject based on the ideXlab platform.
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Spermcast mating with release of zygotes in the small dioecious bivalve Digitaria Digitaria
Scientific Reports, 2020Co-Authors: Pablo Marina, Javier Urra, Juan De Dios Bueno, José Luis Rueda, Serge Gofas, Carmen SalasAbstract:Digitaria Digitaria, a small astartid usually less than 10 mm in length, has a non-brooding behaviour in spite of its limited space for gonad development. This species lives in highly unstable environments with strong currents, which represent a challenge for fertilization and larval settlement. The studied population of D. Digitaria from the Strait of Gibraltar area was dioecious, with significant predominance of females and sexual dimorphism, where females are larger than males. The reproductive cycle is asynchronous throughout the year, without a resting period, but with successive partial spawning events. The presence of stored sperm in the suprabranchial chamber and inside the gonad of some females, together with the release of eggs along the dorsal axis of both gills, points to internal oocyte fertilization. Bacteriocytes were found in the female and male follicle walls, but no bacteria were observed inside any of the gametes. Digitaria Digitaria could represent a “missing link” between spermcast mating bivalves with brooded offspring and bivalves with broadcast release of eggs and sperm. The small size, limiting the oocyte production, together with the unstable environment could represent evolutionary pressures towards sperm uptake in D. Digitaria .
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The periostracum of Digitaria Digitaria (Bivalvia: Astartidae): formation and structure
Journal of Molluscan Studies, 2011Co-Authors: Carmen Salas, Antonio G. Checa, Pablo Marina, José L. RuedaAbstract:The formation, structure and growth of the periostracum of Digitaria Digitaria (L., 1758), a small species of the family Astartidae from the temperate eastern Atlantic and Mediterranean, was studied. The periostracum originates from a row of basal cells, located at the bottom of the periostracal groove. It is initially secreted in the intercellular space between the basal cell row and the first cell row of the outer and middle folds; at this point this periostracum consists of a thin membrane, which comprises two layers (granular and dark homogeneous). The inner epithelial cells of the outer fold are responsible for the secretion and thickening of the third, translucent layer. Along and across the periostracal groove, the periostracum adheres to the outer epithelial cells of the middle mantle fold and develops an undulating form. We observed that the dark layer of the periostracum thickens across the periostracal groove. We could not confirm the involvement of the middle mantle fold in this thickening; a tanning process of the translucent layer appears to be a more likely alternative. During the free periostracum stage the translucent layer is no longer secreted and it becomes transformed into dark layer through a tanning process, which implies a noticeable reduction in periostracal thickness. The outer layer of the periostracum is pitted when newly formed and later the pits become filled by mucus and bacteria-like microorganisms. The first cell row of the outer epithelium of the middle fold serves as template for the large periostracal pits, while the small pits correspond to minor projections of the cells. The mode of formation of pits implies that, rather than being continuous, the periostracal growth proceeds in pulses. The microvilli of the inner epithelial cells of the outer fold show a linear border, while the microvilli of the outer epithelial cells from the apical part of the middle fold show an undulating form. These large undulations of the microvilli in the distal part of the middle fold loosely attach to the periostracum and ease its extrusion from the periostracal groove. This study has also revealed the presence of sensory organs in the distal edge of the middle mantle fold.
Diego Giraldo-cañas - One of the best experts on this subject based on the ideXlab platform.
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A new species of Digitaria (Poaceae: Panicoideae: Paniceae) from Colombia
Caldasia, 2010Co-Authors: Diego Giraldo-cañasAbstract:A new species of Digitaria is described and illustrated. The new species is known only from the Departamento of Meta in the Orinoquia region of Colombia. A checklist of the Colombian species of Digitaria is presented.
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LAS ESPECIES COLOMBIANAS DEL GÉNERO Digitaria (POACEAE: PANICOIDEAE: PANICEAE) 1 The Colombian species of the genus Digitaria (Poaceae: Panicoideae: Paniceae)
2005Co-Authors: Diego Giraldo-cañasAbstract:A systematic study of the Colombian species of the genus Digitaria is presented. The aspects related to the classification, nomenclature, generic affinities, and macro and micromorphological variation are discussed. Some anatomical features of the spikelet and upper anthecium are analyzed. The genus Digitaria is represented in Colombia by 18 species and five sections: Digitaria sect. Calvulae (one species), Digitaria sect. Digitaria (seven species), Digitaria sect. Ischaemum (three species), Digitaria sect. Ternatae (four species), and Digitaria sect. Trichachne (three species). Two species are endemic to Colombia (Digitaria cardenasiana and Digitaria andicola). Digitaria argillacea, Digitaria neesiana, and Digitaria fragilis are excluded from Colombian Flora. Keys to recognize all sections and species that inhabit Colombia are given, as well as description of the species, iconography, uses, vernacular names, specimens examined, geographical distribution, and morphological and ecological observations. The phenomenon of 3-flowered spikelets is recorded for the genus Digitaria and it was verified in two species: Digitaria dioica and Digitaria nuda.
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LAS ESPECIES COLOMBIANAS DEL GÉNERO Digitaria (POACEAE: PANICOIDEAE: PANICEAE)
Caldasia, 2005Co-Authors: Diego Giraldo-cañasAbstract:Se presenta un estudio sistematico, macro y micromorfologico de las especies colombianas del genero Digitaria. Se analizan diversos aspectos relativos a la clasificacion, la nomenclatura, las afinidades genericas y la variacion macro y micromorfologica de los caracteres, asi como algunos aspectos anatomicos de la espiguilla y el antecio superior. El genero Digitaria esta representado en Colombia por 18 especies distribuidas en cinco secciones: Digitaria sect. Calvulae (una especie), Digitaria sect. Digitaria (siete especies), Digitaria sect. Ischaemum (tres especies), Digitaria sect. Ternatae (cuatro especies) y Digitaria sect. Trichachne (tres especies). Dos especies son endemicas de Colombia (Digitaria cardenasiana y Digitaria andicola). Las especies Digitaria argillacea, Digitaria neesiana y Digitaria fragilis se excluyen de la flora de Colombia. Se presentan las claves para reconocer las secciones y las especies presentes en Colombia, asi como tambien las descripciones de estas, la iconografia, los usos, los nombres vulgares, la distribucion geografica y se comentan algunas observaciones morfologicas y ecologicas. Se documenta la presencia de espiguillas trifloras en el genero Digitaria, situacion observada en las especies Digitaria dioica y Digitaria nuda.
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NOVEDADES TAXONÓMICAS Y COROLÓGICAS EN LA TRIBU PANICEAE (POACEAE: PANICOIDEAE) PARA COLOMBIA: Digitaria Y PANICUM
Caldasia, 2003Co-Authors: Diego Giraldo-cañasAbstract:Como resultado de recientes estudios en gramineas colombianas, se propone una nueva especie de Digitaria y se registran cuatro interesantes especies por primera vez para Colombia: Digitaria filiformis (L.) Koeler, Digitaria longiflora (Retz.) Pers., Digitaria nuda Schumach. y Panicum discrepans Doll. Se presentan las descripciones de las especies y se discuten, para cada una de estas, sus relaciones morfologicas, su distribucion geografica y sus preferencias ecologicas. Cada especie esta ilustrada. Asi, la tribu Paniceae esta representada en Colombia por 271 especies y 35 generos, diez de las cuales son endemicas.
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NOVEDADES TAXONÓMICAS Y COROLÓGICAS EN LA TRIBU PANICEAE (POACEAE: PANICOIDEAE) PARA COLOMBIA: Digitaria Y PANICUM 1 Taxonomical and chorological novelties in the Paniceae (Poaceae: Panicoideae) from Colombia: Digitaria and Panicum
2003Co-Authors: Diego Giraldo-cañasAbstract:As result of recent studies of Colombian grasses, one new species of Digitaria is proposed and four interesting species are cited for the first time for Colombia: Digitaria filiformis (L.) Koeler, Digitaria longiflora (Retz.) Pers., Digitaria nuda Schumach., and Panicum discrepans Doll. The descriptions of the species are given. Morphological relationships, geographical distribution, and ecological preferences are discussed under each species. Each species is illustrated. Thus, the tribe Paniceae is represented there by 271 species and 35 genera, with ten endemic species from Colombia.
Pablo Marina - One of the best experts on this subject based on the ideXlab platform.
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Spermcast mating with release of zygotes in the small dioecious bivalve Digitaria Digitaria
Scientific Reports, 2020Co-Authors: Pablo Marina, Javier Urra, Juan De Dios Bueno, José Luis Rueda, Serge Gofas, Carmen SalasAbstract:Digitaria Digitaria, a small astartid usually less than 10 mm in length, has a non-brooding behaviour in spite of its limited space for gonad development. This species lives in highly unstable environments with strong currents, which represent a challenge for fertilization and larval settlement. The studied population of D. Digitaria from the Strait of Gibraltar area was dioecious, with significant predominance of females and sexual dimorphism, where females are larger than males. The reproductive cycle is asynchronous throughout the year, without a resting period, but with successive partial spawning events. The presence of stored sperm in the suprabranchial chamber and inside the gonad of some females, together with the release of eggs along the dorsal axis of both gills, points to internal oocyte fertilization. Bacteriocytes were found in the female and male follicle walls, but no bacteria were observed inside any of the gametes. Digitaria Digitaria could represent a “missing link” between spermcast mating bivalves with brooded offspring and bivalves with broadcast release of eggs and sperm. The small size, limiting the oocyte production, together with the unstable environment could represent evolutionary pressures towards sperm uptake in D. Digitaria .
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The periostracum of Digitaria Digitaria (Bivalvia: Astartidae): formation and structure
Journal of Molluscan Studies, 2011Co-Authors: Carmen Salas, Antonio G. Checa, Pablo Marina, José L. RuedaAbstract:The formation, structure and growth of the periostracum of Digitaria Digitaria (L., 1758), a small species of the family Astartidae from the temperate eastern Atlantic and Mediterranean, was studied. The periostracum originates from a row of basal cells, located at the bottom of the periostracal groove. It is initially secreted in the intercellular space between the basal cell row and the first cell row of the outer and middle folds; at this point this periostracum consists of a thin membrane, which comprises two layers (granular and dark homogeneous). The inner epithelial cells of the outer fold are responsible for the secretion and thickening of the third, translucent layer. Along and across the periostracal groove, the periostracum adheres to the outer epithelial cells of the middle mantle fold and develops an undulating form. We observed that the dark layer of the periostracum thickens across the periostracal groove. We could not confirm the involvement of the middle mantle fold in this thickening; a tanning process of the translucent layer appears to be a more likely alternative. During the free periostracum stage the translucent layer is no longer secreted and it becomes transformed into dark layer through a tanning process, which implies a noticeable reduction in periostracal thickness. The outer layer of the periostracum is pitted when newly formed and later the pits become filled by mucus and bacteria-like microorganisms. The first cell row of the outer epithelium of the middle fold serves as template for the large periostracal pits, while the small pits correspond to minor projections of the cells. The mode of formation of pits implies that, rather than being continuous, the periostracal growth proceeds in pulses. The microvilli of the inner epithelial cells of the outer fold show a linear border, while the microvilli of the outer epithelial cells from the apical part of the middle fold show an undulating form. These large undulations of the microvilli in the distal part of the middle fold loosely attach to the periostracum and ease its extrusion from the periostracal groove. This study has also revealed the presence of sensory organs in the distal edge of the middle mantle fold.
Juan De Dios Bueno - One of the best experts on this subject based on the ideXlab platform.
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Spermcast mating with release of zygotes in the small dioecious bivalve Digitaria Digitaria
Scientific Reports, 2020Co-Authors: Pablo Marina, Javier Urra, Juan De Dios Bueno, José Luis Rueda, Serge Gofas, Carmen SalasAbstract:Digitaria Digitaria, a small astartid usually less than 10 mm in length, has a non-brooding behaviour in spite of its limited space for gonad development. This species lives in highly unstable environments with strong currents, which represent a challenge for fertilization and larval settlement. The studied population of D. Digitaria from the Strait of Gibraltar area was dioecious, with significant predominance of females and sexual dimorphism, where females are larger than males. The reproductive cycle is asynchronous throughout the year, without a resting period, but with successive partial spawning events. The presence of stored sperm in the suprabranchial chamber and inside the gonad of some females, together with the release of eggs along the dorsal axis of both gills, points to internal oocyte fertilization. Bacteriocytes were found in the female and male follicle walls, but no bacteria were observed inside any of the gametes. Digitaria Digitaria could represent a “missing link” between spermcast mating bivalves with brooded offspring and bivalves with broadcast release of eggs and sperm. The small size, limiting the oocyte production, together with the unstable environment could represent evolutionary pressures towards sperm uptake in D. Digitaria .