Ameiva

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform

Guarino R. Colli - One of the best experts on this subject based on the ideXlab platform.

  • Thermal-performance curves and mean values of thermal traits.
    2018
    Co-Authors: Luisa M. Diele-viegas, Laurie J. Vitt, Guarino R. Colli, William E. Magnusson, Donald B. Miles, Barry Sinervo, Fernanda P. Werneck, Juan C. Santos, Carla M. Sette, Gabriel H. O. Caetano
    Abstract:

    A) Chatogekko amazonicus; B) Gonatodes humeralis; C) Copeoglossum nigropunctatum; D) Norops fuscoauratus; E) Plica plica; F) Arthrosaura kockii; G) Arthrosaura reticulata; H) Leposoma percarinatum; I) Ameiva Ameiva; and J) Cnemidophorus cryptus. Gray shaded region shows the 95% confidence interval. Black points represent the results of individual tests at different body temperatures: 15°, 20°, 25°, 30°, 35°, 40° and 43° for species classified as thermoregulators and 20°C, 25°C, 30°C and 35°C for shade-associated species classified as thermoconformers. Short vertical black lines indicate the number of trials at each temperature. Black lines at the curves’ extremes are the critical thermal minimum (CTmin) and critical thermal maximum (CTmax). Topt = optimal temperature; Tb = body temperature; Tpref = preferred temperature; VTmin = minimum voluntary temperature; VTmax = maximum voluntary temperature.

  • Cryptic diversity in South American Teiinae (Squamata, Teiidae) lizards
    Zoologica Scripta, 2013
    Co-Authors: Lilian G. Giugliano, Cristiano Nogueira, Paula Hanna Valdujo, Rosane G. Collevatti, Guarino R. Colli
    Abstract:

    Based on phylogenetic and molecular dating analyses of several species of Cnemidophorus and Ameiva, representing major groups of species of these two genera, we uncover a previously unrecognized Ameiva lineage, which includes described Cnemidophorus parecis from south-western Amazonia. We discuss the diagnosis of Ameiva and Cnemidophorus and the implications of the new taxonomic rearrangement of genera from Teiidae for the monophyly of Ameiva. Based on the conclusion of our analyses, we provide description of a new species named Ameiva jacuba from the central Brazilian Cerrado and a detailed diagnosis for the relocation of C. parecis to Ameiva. We do not adopt here recent taxonomic changes proposed for Teiidae and provide a discussion about them. Finally, based on molecular dating and the distribution of living species, we propose an evolutionary scenario for the origins of South American cis-Andean Ameiva lineages, associated with the topographic subdivision of the Cerrado region during Miocene marine introgressions.

  • ultrastructur eo fspermatozo ao fth elizar dAmeiva Ameiva wit hconsideration so npolymorphis mwithin th efamil yteiida e squamata
    2002
    Co-Authors: Loreny Gimenes Giugliano, R D Teixeira, Guarino R. Colli
    Abstract:

    ABSTRAC T Adetaile ddescriptio no fsper multrastructur eo fth elizar dAmeiv aameiv a(Teiidae )i sprovided. Matur espermatozo aar echaracterize dby :a depressed acrosom ea tth eanterio rportion ;a unilatera lridg ea tthe anterolatera lportion ;a nacrosom evesicl edivide dinto corte xan dmedulla ;medull adivide dint otw oregion swith differen telectron-densities ;paracrystallin esubacrosomal materia lwit hradia lorganizatio ni ntransvers esection ;a pointe dprenuclea rperforatorium ;a stopper-lik eperforatoriu mbas eplat etha tappear sembedde di nth esubacrosoma lmaterial ;th epresenc eo fa nepinuclea rlucen tzone surrounde db yit sow nmembrane ;a larg enuclea rrostrum ;roun dnuclea rshoulders ;a nuclea rspac ea tthe nucleu stip ;a bilatera lstratifie dlamina rstructure ;a centra ldens ebod ywithi nth eproxima lcentriole ;a short midpiece ;a naxonema lmidpiec eaxia lcomponent ;periphera lfiber s3 an d8 grossl yenlarge da tth eanterio rportion o faxoneme ;columna rmitochondri awit hlinea rcristae; soli ddens ebodie sarrange da sring so rspirals ;a triangular-shape dannulu si ntransvers esection ;a fibrous sheat hint oth emidpiece ;a thi nzon eo fcytoplas ma tthe anterio rportio no fth eprincipa lpiece ;an da sligh tdecreas ei ndiamete ro fth eprincipa lpiec eimmediatel yafter th eannulus .Comparison swit hCnemidophoru ssexlineatu san dMicrablepharu smaximilian ifaile dt oidentify uniqu esper multrastructur etrait so fTeiida eo rTeiioidea (Teiida e Gymnophthalmidae) .Hig hlevel so fpolymorphis mbetwee nAmeiv aan dCnemidophorus ,tw oclosely relate dgener ao fth efamil yTeiidae ,wer edetected ,suggestin gtha textensiv esamplin gwithi nsquamat efamilies i sessentia li fsper multrastructur edat aar et ob euse din phylogeneti canalyse sa tthi staxonomi clevel .J .Morphol. 253:26 4‐271 ,2002. ©200 2Wiley-Liss ,Inc.

  • A comparative ultrastructural study of spermatozoa of the teiid lizards Cnemidophorus gularis gularis, Cnemidophorus ocellifer, and Kentropyx altamazonica (Reptilia, Squamata, Teiidae)
    Tissue & cell, 2002
    Co-Authors: R D Teixeira, Guarino R. Colli, D. M. Scheltinga, S.e. Trauth, Sônia Nair Báo
    Abstract:

    The ultrastructure of the spermatozoa of Cnemidophorus gularis gularis, Cnemidophorus ocellifer, and Kentropyx altamazonica is described for the first time. Mature spermatozoa of Cnemidophorus spp. and K. altamazonica differ in the occurrence of a perforatorial base plate, the enlargement of axonemal fibers 3 and 8, and shape of mitochondria. The comparisons of the ultrastructure sperm of Cnemidophorus spp. and K. altamazonica with Ameiva Ameiva [J. Morphol. (2002) in press] suggest that Ameiva and Cnemidophorus are more similar to each other than either is to Kentropyx. Statistical analyses reveal that sperm of all three species studied are significantly different in the following dimensions: head, acrosome, distal centriole length, and nuclear shoulders width. There was no variable statistically different between the Cnemidophorus spp. only. The length of the tail, midpiece, entire sperm, and nuclear rostrum are significantly different between K. altamazonica and Cnemidophorus spp. Our results indicate that sperm ultrastructure presents intra and intergeneric variability.

  • Use of naturally and anthropogenically disturbed habitats in Amazonian rainforest by the teiid lizard Ameiva Ameiva
    Biological Conservation, 1999
    Co-Authors: Shawn S. Sartorius, Laurie J. Vitt, Guarino R. Colli
    Abstract:

    Abstract We studied the effects of natural and anthropogenic habitat disturbances on environmental temperatures and their consequent effects on thermoregulation and habitat use of Ameiva Ameiva in a complex habitat matrix of primary tropical forest and several types of disturbed forest in Amazonian Brazil. Data on Ameiva Ameiva from other regions in Brazil with habitats that have little canopy coverage are compared with data from rain forest sites to determine if activity of rain forest Ameiva is temporally or spatially limited by the thermal opportunities available in shaded environments. Ameiva Ameiva preferentially used disturbed habitats in rain forest regions. These sites had significantly higher environmental temperatures than did surrounding undisturbed rain forest. Environmental temperature distributions indicate that the closed canopy rain forest is a thermally marginal habitat for Ameiva Ameiva and that high temperatures resulting from forest clearing are likely to enable Ameiva Ameiva to increase foraging activity in adjacent forest edges above what is possible in the continuous interior forest. Ameiva Ameiva from rain forest, cerrado and savanna regions of Brazil had significantly lower body temperatures than Ameiva from caatinga, an open habitat type with little canopy coverage. This difference is probably due to high ambient temperatures and the high availability of basking sites in open habitats and suggests a thermal constraint on habitat use and time of activity for Ameiva in closed canopy habitats.

Katherine E Horak - One of the best experts on this subject based on the ideXlab platform.

  • effects of brodifacoum and diphacinone exposure on four species of reptiles tissue residue levels and survivorship
    Pest Management Science, 2020
    Co-Authors: Richard E Mauldin, Gary W Witmer, Susan A Shriner, Rachael S Moulton, Katherine E Horak
    Abstract:

    BACKGROUND: Anticoagulant rodenticides are used worldwide to control pest rodent species. However, the risks posed to non‐target reptiles have not been well characterized. In this study, 46 giant Ameivas (Ameiva Ameiva), 39 boa constrictors (Boa constrictor), 33 wood turtles (Rhinoclemmys pulcherrima), and 47 green iguanas (Iguana iguana) were orally dosed with one of two levels of either diphacinone or brodifacoum anticoagulant in propylene glycol solutions. Dosages were derived using daily food intake (DFI) equations, converting DFI to an equivalent anticoagulant bait amount and gavaging the solution volume needed to deliver the quantity of anticoagulant in that amount of bait. Animals were dosed on days 0 and 7 and monitored for a further 7 days for signs of anticoagulant intoxication and differences in behaviors and postures. At necropsy on day 14, animals were examined for thoracic and abdominal bleeding, and both tissue and organ samples were taken for histology. Liver and whole‐body anticoagulant residues were assessed. RESULTS: No turtles or boas died due to anticoagulant exposure. However, anticoagulant intoxication was suspected in one iguana dosed with brodifacoum. A few treated Ameivas died but exhibited no hemorrhaging. Liver residue levels were higher than whole‐body remainder residue levels for all species. Unlike the other species, turtles had higher diphacinone residue levels than brodifacoum. CONCLUSION: Turtles and boas exhibited a relative insensitivity to diphacinone and brodifacoum, while the lizards appeared to be somewhat more sensitive to these compounds. This study provides data for future assessments of the risks to these species associated with anticoagulant use. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.

Jenniffer Velasquez - One of the best experts on this subject based on the ideXlab platform.

  • ecologia termica y patron de actividad del lagarto Ameiva Ameiva sauria teiidae en el oriente de venezuela
    Acta Biologica Venezuelica, 2013
    Co-Authors: Jenniffer Velasquez, Luis Alejandro Gonzalez Sanchez
    Abstract:

    Se estudio la ecologia termica y patron de actividad de Ameiva Ameiva en un bosque tropofilo del estado Sucre, Venezuela. La temperatura media corporal de individuos activos fue de 38,78 ± 0,89 oC y oscilo entre 37 y 39,80 oC. La temperatura corporal y la del sustrato no se correlacionaron significativamente, tanto en sequia como en lluvia, sugiriendo que la especie es heliotermica con una capacidad termorregulatoria activa. Se detectaron diferencias significativas en la distribucion de frecuencias de Tc en ambos sexos, tanto en sequia como en lluvia y un patron de actividad bimodal en ambos periodos climaticos.

  • food habits of the lizard Ameiva Ameiva linnaeus 1758 sauria 1758 sauria teiidae in a tropophic forest of sucre state venezuela
    Acta biológica venezuelica, 2008
    Co-Authors: Luis Alejandro Gonzalez, Jenniffer Velasquez, Hernan Ferrer, James Garcia, Francia Cala, Jose Penuela
    Abstract:

    Food habits among sexes of Ameiva Ameiva were evaluated by the frequency of occurrence, trophic dominance, and diet similarity methods during periods of rain and drought in a tropophic forest in La Llanada Vieja, Sucre State, Venezuela. 431 prey items were identified in 20 stomachs analyzed. Diet for both periods showed a high frequency for Coleoptera, plant material, Isoptera, Nematoda, Araneae, and reptilian rests. Males and females showed differences in diet during the climatic periods analyzed. Females showed higher stomach volumes values than males. Results suggest the species is mainly insectivorous.

  • variacion morfologica de la region cefalica del lagarto Ameiva Ameiva linnaeus 1758 sauria teiidae en un bosque humedo del parque nacional el avila venezuela
    SABER. Revista Multidisciplinaria del Consejo de Investigación de la Universidad de Oriente, 2007
    Co-Authors: Luis Alejandro S Gonzalez, Hector Lopezrojas, Ana Bonillarivero, Antulio Prieto, Jenniffer Velasquez
    Abstract:

    Resumen es: En 36 ejemplares (18 hembras y 18 machos) de una poblacion del lagarto Ameiva Ameiva capturados en un bosque humedo del municipio Zamora del estado Miran...

  • nichos troficos de los lagartos Ameiva Ameiva y plica plica en un bosque humedo tropical del estado miranda venezuela
    SABER. Revista Multidisciplinaria del Consejo de Investigación de la Universidad de Oriente, 2006
    Co-Authors: Luis Alejandro S Gonzalez, Antulio S Prieto, Luis Alberto Ruiz Martinez, Jenniffer Velasquez
    Abstract:

    Se evaluo la similitud, amplitud del nicho trofico y sobreposicion de la dieta de los lagartos insectivoros Ameiva Ameiva y Plica plica , analizando los contenidos estomacales de ejemplares capturados en un bosque humedo tropical del estado Miranda, Venezuela, desde enero hasta agosto de 1995. Ambas especies habitan en la misma area y se alimentan generalmente de las mismas clases de presas. Los altos valores de similitud trofica de Sorensen (0,78) y Jaccard (0,64) indicaron que ambas dietas son similares, tendencia que se mantiene al considerar la distancia Euclideana (0,71), lo cual indica una diferencia de 29% entre ambos lagartos. Los indices de amplitud del nicho muestran que A. Ameiva presenta un mayor valor (0,311-0,797) debido a la alta actividad de alimentacion que desarrolla, principalmente en el sotobosque. P. plica , por el contrario presenta un menor valor (0,062-0,595), ya que ella es activa sobre troncos de arboles y con preferencias a capturar hormigas. La sobreposicion de la dieta, entre ambas especies, es baja (23,40%), variando segun el indice utilizado. Se discute la coexistencia de ambas especies, de acuerdo a sus preferencias dietarias y a la influencia del habitat sobre el modo de forrajeo de ambas especies. Palabras clave: Ameiva Ameiva, Plica plica , lagartos, dieta, nicho trofico, bosque humedo, competencia, Venezuela. ABSTRACT Similarity, niche breadth, and overlap values in the diet of two insectivorous lizards ( Ameiva Ameiva and Plica plica ) were studied using different indices and assessing the stomach contents of animals collected in a rainforest in the state of Miranda, Venezuela from January to August 1995. Both species inhabit the same geographic area and eat the same general kinds of prey. The high values of Sorensen’s Quotient of similarity (0.78) and Jaccard’s coefficient (0.64) showed that both diets bear great likeness, a tendency that holds true when the Euclidean distance (0.71) is considered, indicative of a 29% difference between both lizards. Niche breadth indices show that A. Ameiva has a wider foraging niche (0.311-0.797) due to an active foraging habit, especially on the forest floor. Plica plica has a narrower niche breadth (0.062-0.595), is primarily active on tree trunks, and shows preference for ants. Diet overlap (23.40%) was low and varied according to the index used. The coexistence of both species according to food preferences and to the influence of habitat on foraging habits is discussed. Key words: Ameiva Ameiva, Plica plica , lizards, diet, trophic niche, rainforest, competition, Venezuela

Richard E Mauldin - One of the best experts on this subject based on the ideXlab platform.

  • effects of brodifacoum and diphacinone exposure on four species of reptiles tissue residue levels and survivorship
    Pest Management Science, 2020
    Co-Authors: Richard E Mauldin, Gary W Witmer, Susan A Shriner, Rachael S Moulton, Katherine E Horak
    Abstract:

    BACKGROUND: Anticoagulant rodenticides are used worldwide to control pest rodent species. However, the risks posed to non‐target reptiles have not been well characterized. In this study, 46 giant Ameivas (Ameiva Ameiva), 39 boa constrictors (Boa constrictor), 33 wood turtles (Rhinoclemmys pulcherrima), and 47 green iguanas (Iguana iguana) were orally dosed with one of two levels of either diphacinone or brodifacoum anticoagulant in propylene glycol solutions. Dosages were derived using daily food intake (DFI) equations, converting DFI to an equivalent anticoagulant bait amount and gavaging the solution volume needed to deliver the quantity of anticoagulant in that amount of bait. Animals were dosed on days 0 and 7 and monitored for a further 7 days for signs of anticoagulant intoxication and differences in behaviors and postures. At necropsy on day 14, animals were examined for thoracic and abdominal bleeding, and both tissue and organ samples were taken for histology. Liver and whole‐body anticoagulant residues were assessed. RESULTS: No turtles or boas died due to anticoagulant exposure. However, anticoagulant intoxication was suspected in one iguana dosed with brodifacoum. A few treated Ameivas died but exhibited no hemorrhaging. Liver residue levels were higher than whole‐body remainder residue levels for all species. Unlike the other species, turtles had higher diphacinone residue levels than brodifacoum. CONCLUSION: Turtles and boas exhibited a relative insensitivity to diphacinone and brodifacoum, while the lizards appeared to be somewhat more sensitive to these compounds. This study provides data for future assessments of the risks to these species associated with anticoagulant use. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.

Laurie J. Vitt - One of the best experts on this subject based on the ideXlab platform.

  • Thermal-performance curves and mean values of thermal traits.
    2018
    Co-Authors: Luisa M. Diele-viegas, Laurie J. Vitt, Guarino R. Colli, William E. Magnusson, Donald B. Miles, Barry Sinervo, Fernanda P. Werneck, Juan C. Santos, Carla M. Sette, Gabriel H. O. Caetano
    Abstract:

    A) Chatogekko amazonicus; B) Gonatodes humeralis; C) Copeoglossum nigropunctatum; D) Norops fuscoauratus; E) Plica plica; F) Arthrosaura kockii; G) Arthrosaura reticulata; H) Leposoma percarinatum; I) Ameiva Ameiva; and J) Cnemidophorus cryptus. Gray shaded region shows the 95% confidence interval. Black points represent the results of individual tests at different body temperatures: 15°, 20°, 25°, 30°, 35°, 40° and 43° for species classified as thermoregulators and 20°C, 25°C, 30°C and 35°C for shade-associated species classified as thermoconformers. Short vertical black lines indicate the number of trials at each temperature. Black lines at the curves’ extremes are the critical thermal minimum (CTmin) and critical thermal maximum (CTmax). Topt = optimal temperature; Tb = body temperature; Tpref = preferred temperature; VTmin = minimum voluntary temperature; VTmax = maximum voluntary temperature.

  • Niche segregation among sympatric Amazonian teiid lizards.
    Oecologia, 2000
    Co-Authors: Laurie J. Vitt, Shawn S. Sartorius, Teresa Avila-pires, Maria Cristina Esposito, Donald B. Miles
    Abstract:

    We examined standard niche axes (time, place, and food) for three sympatric teiid lizards in the Amazon rain forest. Activity times during the day were similar among species. Ameiva Ameiva were in more open microhabitats and had higher body temperatures compared with the two species of Kentropyx. Microhabitat overlaps were low and not significantly different from simulations based on Monte Carlo analysis. Grasshoppers, crickets, and spiders were important in the diets of all three species and many relatively abundant prey were infrequently eaten (e.g., ants). Dietary overlaps were most similar between the two species of Kentropyx even though microhabitat overlaps were relatively low. A Monte Carlo analysis on prey types revealed that dietary overlaps were higher at all ranks than simulated overlaps indicating that use of prey is not random. Although prey size was correlated with lizard body size, there were no species differences in adjusted prey size. A. Ameiva ate more prey items at a given body size than either species of Kentropyx. Body size varies among species, with A. Ameiva being the largest and K. altamazonica the smallest. The two species of Kentropyx are most distant morphologically, with A. Ameiva intermediate. The most distant species morphologically are the most similar in terms of prey types. A morphological analysis including 15 species from four genera revealed patterns of covariation that reflected phylogenetic affinities (i.e., taxonomic patterns are evident). A cluster analysis revealed that A. Ameiva, K. pelviceps, and K. altamazonica were in the same morphological group and that within that group, A. Ameiva differed from the rest of the species. In addition, K. pelviceps and K. altamazonica were distinguishable from other species of Kentropyx based on morphology.

  • Use of naturally and anthropogenically disturbed habitats in Amazonian rainforest by the teiid lizard Ameiva Ameiva
    Biological Conservation, 1999
    Co-Authors: Shawn S. Sartorius, Laurie J. Vitt, Guarino R. Colli
    Abstract:

    Abstract We studied the effects of natural and anthropogenic habitat disturbances on environmental temperatures and their consequent effects on thermoregulation and habitat use of Ameiva Ameiva in a complex habitat matrix of primary tropical forest and several types of disturbed forest in Amazonian Brazil. Data on Ameiva Ameiva from other regions in Brazil with habitats that have little canopy coverage are compared with data from rain forest sites to determine if activity of rain forest Ameiva is temporally or spatially limited by the thermal opportunities available in shaded environments. Ameiva Ameiva preferentially used disturbed habitats in rain forest regions. These sites had significantly higher environmental temperatures than did surrounding undisturbed rain forest. Environmental temperature distributions indicate that the closed canopy rain forest is a thermally marginal habitat for Ameiva Ameiva and that high temperatures resulting from forest clearing are likely to enable Ameiva Ameiva to increase foraging activity in adjacent forest edges above what is possible in the continuous interior forest. Ameiva Ameiva from rain forest, cerrado and savanna regions of Brazil had significantly lower body temperatures than Ameiva from caatinga, an open habitat type with little canopy coverage. This difference is probably due to high ambient temperatures and the high availability of basking sites in open habitats and suggests a thermal constraint on habitat use and time of activity for Ameiva in closed canopy habitats.

  • Geographical ecology of a Neotropical lizard: Ameiva Ameiva (Teiidae) in Brazil
    Canadian Journal of Zoology, 1994
    Co-Authors: Laurie J. Vitt, Guarino R. Colli
    Abstract:

    The large-bodied teiid lizard Ameiva Ameiva was studied at eight different sites in four major South American habitats of Brazil: caatinga, cerrado, Amazonian rain forest, and Amazonian savanna. We found striking similarity in ecological attributes of this lizard among very different habitats. Activity is concentrated in late morning and early afternoon; active body temperatures average 37.9 ± 0.09 °C and vary little among sites or throughout the day; the diet consists of a variety of vertebrates and invertebrates but is dominated by grasshoppers, roaches, beetles, spiders, and insect larvae; and niche breadths for prey are similar among study sites but the actual composition of the diets varies. There is minimal morphological variation among sites (mostly size); the most striking morphological variation is between the sexes. Males reach larger body sizes and have relatively larger heads than females. Juveniles have relatively larger heads than would be predicted on the basis of body size alone. Sexual se...