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Ricarda Riina - One of the best experts on this subject based on the ideXlab platform.
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Croton calcareus: a new species of dragon’s blood (Euphorbiaceae) from dry forest in the state of Chiapas, Mexico
'Museum National D''Histoire Naturelle', 2020Co-Authors: Leticia Mateo-ramírez, Ricarda RiinaAbstract:We describe Croton calcareus Riina & Mateo-Ram. sp. nov., a new species in Croton section Cyclostigma (dragon’s blood trees) from the state of Chiapas (Mexico). This species is a small tree growing in dry forest on calcareous substrates. Both morphological and molecular data support C. calcareus sp. nov. as a new species closely related to C. redolens, another dry forest taxon from northern Venezuela. We provide illustrations, a distribution map and suggestions for species conservation status. The new species along with Croton draco are the only known representatives of C. section Cyclostigma occurring in Mexico
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four new species of dragon s blood Croton euphorbiaceae from south america
Systematic Botany, 2018Co-Authors: Ana Carla Feio, Paul E Berry, Malu I Orerengifo, Ricarda RiinaAbstract:We describe and illustrate four new species of dragon's blood trees (Croton sect. Cyclostigma) from western South America. Three of the species, Croton beckii from Bolivia and Peru, C. camposii fromPeru, and C. santamartensis fromColombia, grow inmontane Andean forest,whereas C. tumbesinus occurs in dry forest of the Tumbes/Piura ecoregion of western Ecuador and Peru. The characters that place them in Croton sect. Cyclostigma include the arborescent habit, the presence of reddish to yellowish latex, an indument of stellate trichomes, conspicuous and persistent stipules, acropetiolar/basilaminar nectary glands, and terminal inflorescences with bisexual cymules at the base. These new species give additional support for the Andean region being the main center of diversity of this Neotropical Croton clade, as well as being a region whose biodiversity knowledge is still incomplete.
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Croton sapiifolius mull arg in a new occurrence for the state of espirito santo brazil
Hoehnea, 2016Co-Authors: Rafaela Freitas Dos Santos, Ricarda Riina, Maria Beatriz Rossi CaruzoAbstract:ABSTRACT - ( Croton sapiifolius Mull.Arg.: a new occurrence for the State of Espirito Santo, Brazil). While studying Croton material collected in Espirito Santo, we found several specimens of Croton sapiifolius , a species previously restricted to the State of Bahia. The present paper updates our knowledge about the taxonomy, habitat and geographic distribution of C. sapiifolius . This finding increases the number of known Croton species occurring in Espirito Santo State to 20 and contributes to the knowledge of Croton of the Brazilian Atlantic Forest.Keywords: Atlantic Forest, Crotoneae, Flora, Restinga vegetationRESUMO - ( Croton sapiifolius Mull.Arg.: uma nova ocorrencia para o Estado do Espirito Santo, Brasil). Durante visita aos herbarios do Estado do Espirito Santo, foram encontrados especimes de C. sapiifolius para este Estado, uma especie conhecida ate o momento apenas para o Estado da Bahia. Neste trabalho sao apresentados dados atuais sobre a taxonomia e distribuicao geografica de
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redefinition of Croton macrobothrys euphorbiaceae a tree species from the brazilian atlantic forest with the description of a new subspecies
Phytotaxa, 2016Co-Authors: Maria Beatriz Rossi Caruzo, Rafaela Freitas Dos Santos, Ana Carla Feio, Renata Maria Strozi Alves Meira, Ricarda RiinaAbstract:Croton macrobothrys subsp. septentrionalis , a new subspecies of section Cyclostigma from the Brazilian Atlantic Forest, is here described and illustrated. It occurs in moist forests between 100–1000 m of elevation in the states of Bahia, Alagoas, and NE Minas Gerais. Given this new finding, we expand the morphological delineation of Croton macrobothrys and update its geographic distribution. We also provide a key to the two subspecies and identify the name C. macrobothrys var. microbothrys as a nomen nudum under Croton echioideus in section Adenophylli .
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a revised infrageneric classification and molecular phylogeny of new world Croton euphorbiaceae
Taxon, 2011Co-Authors: Ricarda Riina, Paul E BerryAbstract:Croton (Euphorbiaceae) is a large and diverse group of plants that is most species-rich in the tropics. We update the infrageneric classification of the New World species of Croton with new evidence from phylogenetic analyses of DNA sequence data from all three genomes. The relationships of species that were previously placed in conflicting positions by nuclear and chloroplast data, such as C. cupreatus , C. poecilanthus, and C. setiger , are further resolved by adding the nuclear EMB2765 and mitochondrial rps3 genes to the molecular sampling. Analyses of rps3 reveal an accelerated rate of evolution within Croton subg. Geiseleria , the only one of the four subgenera that contains numerous herbaceous, annual species. We provide morphological descriptions, species lists, and a key to the 31 sections and 10 subsections recognized in the New World. New taxa that we describe include C. sects. Alabamenses , Argyranthemi , Cordiifolii , Corinthii , Cupreati , Luetzelburgiorum , Nubigeni , Olivacei , Pachypodi , Prisci , and C. subsects. Cubenses , Jamaicenses , and Sellowiorum. Additional transfers are made to the ranks of subgenus, section, and subsection. A total of 712 species of Croton are currently recognized for the New World, with 702 of them assigned here to section.
Paul E Berry - One of the best experts on this subject based on the ideXlab platform.
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a new species of Croton euphorbiaceae from a madagascan lineage discovered in coastal kenya
Systematic Botany, 2020Co-Authors: Veronicah Mutele Ngumbau, Paul E Berry, Mwadime Nyange, Itambo Malombe, Guangwan Hu, Qing-feng WangAbstract:Croton kinondoensis, a new species from Kenya, is described and illustrated here with photographs. It is found in the sacred Kaya Kinondo Forest, one of the last remaining coastal forests patches in Kenya. Its morphology and systematic position based on ITS and trnL-F DNA sequence data clearly place it within the Adenophorus Group of Croton, a clade of ca. 15 species otherwise known only from Madagascar and the Comoros Archipelago. Its closest affinities appear to lie with Croton mayottae, from the island of Mayotte, and C. menabeensis, from northwestern Madagascar. This new species likely represents an independent dispersal of Croton from Madagascar to mainland Africa.
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four new species of dragon s blood Croton euphorbiaceae from south america
Systematic Botany, 2018Co-Authors: Ana Carla Feio, Paul E Berry, Malu I Orerengifo, Ricarda RiinaAbstract:We describe and illustrate four new species of dragon's blood trees (Croton sect. Cyclostigma) from western South America. Three of the species, Croton beckii from Bolivia and Peru, C. camposii fromPeru, and C. santamartensis fromColombia, grow inmontane Andean forest,whereas C. tumbesinus occurs in dry forest of the Tumbes/Piura ecoregion of western Ecuador and Peru. The characters that place them in Croton sect. Cyclostigma include the arborescent habit, the presence of reddish to yellowish latex, an indument of stellate trichomes, conspicuous and persistent stipules, acropetiolar/basilaminar nectary glands, and terminal inflorescences with bisexual cymules at the base. These new species give additional support for the Andean region being the main center of diversity of this Neotropical Croton clade, as well as being a region whose biodiversity knowledge is still incomplete.
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a nomenclator of Croton euphorbiaceae in madagascar the comoros archipelago and the mascarene islands
PhytoKeys, 2017Co-Authors: Paul E Berry, Kent KainulainenAbstract:: All published names of Croton from Madagascar, the Comoros, and the Mascarenes are treated here. We indicate which names are currently accepted (123 native species and 1 introduced), which ones we consider to be heterotypic synonyms (188), which ones are doubtful (25), and which ones should be excluded (5). We newly designate lectotypes for 108 names, and epitypes for C. anisatus Baill., C. nobilis Baill., and C. submetallicus Baill. A total of 133 names are newly treated as synonyms. One new combination is made, Croton basaltorum (Leandri) P.E.Berry for C. antanosiensis var. basaltorum Leandri, and one new name is proposed, Croton toliarensis B.W.vanEe & Kainul. for C. tranomarensis var. rosmarinifolius Radcl.-Sm.
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rediscovery of two species of Croton euphorbiaceae from littoral habitats of eastern madagascar
Candollea, 2017Co-Authors: Kent Kainulainen, Paul E BerryAbstract:Abstract Kainulainen, K., P.E. Berry & B. Van Ee (2017). Rediscovery of two species of Croton (Euphorbiaceae) from littoral habitats of eastern Madagascar. Candollea 72: 35–44. In English, English and French abstracts. Two species of Croton L. (Euphorbiaceae) previously reported only from their type specimens, Croton chapelieri Baill. and Croton vatomandrensis Leandri, are reevaluated here and found to be geographically widespread along the eastern coastline of Madagascar. We provide updated descriptions, lists of selected additional specimens, distribution maps, and photographs of both species. We also designate an epitype for Croton chapelieri and a lectotype for Croton vatomandrensis. Croton chapelieri was the source of considerable taxonomic confusion, and we treat as synonyms here for the first time Croton aymoninorum Leandri, Croton louvelii Leandri, Croton daphniphylloides Radcl.-Sm., Croton daphniphyllum Radcl.-Sm., Croton daphniphyllum var. hirsutus Radcl.-Sm., and Croton rhododendroides Radcl-Sm...
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phylogenetic relationships and a new sectional classification of Croton euphorbiaceae in australia
Australian Systematic Botany, 2015Co-Authors: Paul I Forster, Paul E BerryAbstract:A molecular phylogeny, morphological descriptions, species lists and a key to the sections of Croton L. (Euphorbiaceae) recognised for Australia are presented. The molecular phylogenetic results supported the recognition of six sections, to account for the 29 native Australian species. The monophyly of each of these sections was highly supported in the Bayesian and maximum-likelihood analyses of nuclear ITS and plastid trnL–F DNA sequences, whereas their relationships to each other and to other groups were less well resolved. Croton may represent one, two or three separate arrivals to Australia, with support for hypotheses of subsequent dispersals from Australia to Pacific islands and to Asia. Croton sections Argyrati, Arnhemici, Caudati, Dockrilliorum and Insulares are newly described. Croton section GymnoCroton Baill., previously placed in synonymy, is again recognised. Croton armstrongii S.Moore is excluded from the Australian flora.
Nicholas T Karonis - One of the best experts on this subject based on the ideXlab platform.
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a comparison of proton stopping power measured with proton ct and x ray ct in fresh postmortem porcine structures
Medical Physics, 2021Co-Authors: Don F Dejongh, Ethan A Dejongh, V Rykalin, Greg Defillippo, Mark Pankuch, Andrew W Best, George Coutrakon, Kirk L Duffin, Nicholas T KaronisAbstract:PURPOSE Currently, calculations of proton range in proton therapy patients are based on a conversion of CT Hounsfield units of patient tissues into proton relative stopping power. Uncertainties in this conversion necessitate larger proximal and distal planned target volume margins. Proton CT can potentially reduce these uncertainties by directly measuring proton stopping power. We aim to demonstrate proton CT imaging with complex porcine samples, to analyze in detail three-dimensional regions of interest, and to compare proton stopping powers directly measured by proton CT to those determined from x-ray CT scans. METHODS We have used a prototype proton imaging system with single proton tracking to acquire proton radiography and proton CT images of a sample of porcine pectoral girdle and ribs, and a pig's head. We also acquired close in time x-ray CT scans of the same samples and compared proton stopping power measurements from the two modalities. In the case of the pig's head, we obtained x-ray CT scans from two different scanners and compared results from high-dose and low-dose settings. RESULTS Comparing our reconstructed proton CT images with images derived from x-ray CT scans, we find agreement within 1% to 2% for soft tissues and discrepancies of up to 6% for compact bone. We also observed large discrepancies, up to 40%, for cavitated regions with mixed content of air, soft tissue, and bone, such as sinus cavities or tympanic bullae. CONCLUSIONS Our images and findings from a clinically realistic proton CT scanner demonstrate the potential for proton CT to be used for low-dose treatment planning with reduced margins.
Don F Dejongh - One of the best experts on this subject based on the ideXlab platform.
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a comparison of proton stopping power measured with proton ct and x ray ct in fresh postmortem porcine structures
Medical Physics, 2021Co-Authors: Don F Dejongh, Ethan A Dejongh, V Rykalin, Greg Defillippo, Mark Pankuch, Andrew W Best, George Coutrakon, Kirk L Duffin, Nicholas T KaronisAbstract:PURPOSE Currently, calculations of proton range in proton therapy patients are based on a conversion of CT Hounsfield units of patient tissues into proton relative stopping power. Uncertainties in this conversion necessitate larger proximal and distal planned target volume margins. Proton CT can potentially reduce these uncertainties by directly measuring proton stopping power. We aim to demonstrate proton CT imaging with complex porcine samples, to analyze in detail three-dimensional regions of interest, and to compare proton stopping powers directly measured by proton CT to those determined from x-ray CT scans. METHODS We have used a prototype proton imaging system with single proton tracking to acquire proton radiography and proton CT images of a sample of porcine pectoral girdle and ribs, and a pig's head. We also acquired close in time x-ray CT scans of the same samples and compared proton stopping power measurements from the two modalities. In the case of the pig's head, we obtained x-ray CT scans from two different scanners and compared results from high-dose and low-dose settings. RESULTS Comparing our reconstructed proton CT images with images derived from x-ray CT scans, we find agreement within 1% to 2% for soft tissues and discrepancies of up to 6% for compact bone. We also observed large discrepancies, up to 40%, for cavitated regions with mixed content of air, soft tissue, and bone, such as sinus cavities or tympanic bullae. CONCLUSIONS Our images and findings from a clinically realistic proton CT scanner demonstrate the potential for proton CT to be used for low-dose treatment planning with reduced margins.
Selene Maia De Morais - One of the best experts on this subject based on the ideXlab platform.
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Further insecticidal activities of essential oils from Lippia sidoides and Croton species against Aedes aegypti L.
Parasitology Research, 2013Co-Authors: Glauber Pacelli Gomes Lima, Gabrielle Paula Freire, Arcelina Pacheco Cunha, Nágila Maria Pontes Silva Ricardo, Terezinha Maria Souza, Davi Felipe Farias, Selene Maia De Morais, Ana Fontenele Urano CarvalhoAbstract:This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species ( Croton zehntneri , Croton nepetaefolius , Croton argyrophylloides , and Croton sonderianus ) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC_50 values ranging from 66.4 to 143.2 μg mL^−1, larvicidal activity with LC_50 ranging from 25.5 to 94.6 μg mL^−1, and pupicidal action with PC_50 ranging from 276.8 to over 500 μg mL^−1. Only L. sidoides , C. zehntneri , and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD_50 values of 35.3, 45.3, and 45.8 μg mL^−1, respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD_50 > 6,000 mg.kg^−1) while C. nepetaefolius , C. zehntneri , and L. sidoides oils are moderately toxic (LD_50 3,840; 3,464, and 2,624 mg.kg^−1, respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals.
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antifungal activity of essential oils of Croton species from the brazilian caatinga biome
Journal of Applied Microbiology, 2008Co-Authors: Raquel Oliveira Dos Santos Fontenelle, Selene Maia De Morais, Erika H S Brito, R S N Brilhante, Rossana De Aguiar Cordeiro, Nilberto R F Nascimento, M R Kerntopf, J J C Sidrim, Marcos Fabio Gadelha RochaAbstract:Aims: To find new antifungal agents among essential oils from Brazilian Croton species. Methods and Results: Plant leaves were steam distilled and the obtained essential oils were analyzed by gas chromatography/mass spectroscopy. The main constituents were estragole and anethole for Croton zehntneri, methyl-eugenol and bicyclogermacrene for Croton nepetaefolius and spathulenol and bicyclogermacrene for Croton argyrophylloides. The antifungal activity of essential oils was evaluated against Candida albicans, Candida tropicalis and Microsporum canis by the agar-well diffusion method and the minimum inhibitory concentration (MIC) by the broth microdilution method. Essential oils of Croton species demonstrated better activity against M. canis. Among the three plants C. argyrophylloides showed the best results, with MIC ranging from 9 to 19 μg ml−1. The acute administration of the essential oil up to 3 g kg−1 by the oral route to mice was devoid of overt toxicity. Conclusions: The studied essential oils are active in vitro against the dermatophyte M. canis and present relative lack of acute toxicity in vivo. Significance and Impact of the Study: Because of its antifungal activity and low toxicity, the essential oils of studied Croton species are promising sources for new phytotherapeutic agents to treat dermatophytosis.
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effect of stalk and leaf extracts from euphorbiaceae species on aedes aegypti diptera culicidae larvae
Revista Do Instituto De Medicina Tropical De Sao Paulo, 2006Co-Authors: Maria Goretti Araujo De Lima, Selene Maia De Morais, Ismalia Cassandra Costa Maia, Bruna Dantas De Sousa, Silvia Maria FreitasAbstract:The objective of this study was to evaluate the larvicidal activity of essential oil aqueous solutions (hydrolates) obtained by steam distillation of stalks and leaves of Croton argyrophylloides, Croton nepetaefolius, Croton sonderianus and Croton zehntneri against Aedes aegypti larvae. Twenty-five larvae of third instar were placed in plastic beckers, containing the hydrolates (50 mL), in a four repetitions scheme. Water was used as control and the number of dead larvae was counted after 24 hours. The data obtained were submitted to Variance Analysis and Tukey test. Significant differences were observed among the hydrolates from different species and from different parts of each plant (p < 0.001). The hydrolates of stalk and leaf from C. nepetaefolius and C. zehntneri and leaf hydrolate of C. argyrophylloides presented 100% mortality against larvae. The compounds present in C. zenhtneri and C. nepetaefolius are oxygenated phenylpropanoids that are more soluble in water than the monoterpenes and sesquiterpenes detected in the oils of C. argyrophylloides and C. sonderianus. This study showed that all species analyzed presented compounds with larvicidal properties, with differences between each plant parts.