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1.
Rev. argent. microbiol ; 53(2): 31-40, June 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1376405

RESUMO

Abstract In the present study, pentastomids belonging to the order Cephalobaenida were isolated from the lungs of Berber skinks Eumeces schneideri (Famiy: Scincidae), which were morphologically described by light and scanning electron microscopy and taxonomically justi- fied by 18s rDNA molecular analyses of the parasites. Seventeen host specimens were collected from well-vegetated wadis at high altitudes, Jizan, Saudi Arabia as new type locality; twelve specimens (70.59%) were infected. All of the recovered parasites were adults, possessed small broadly triangular cephalothorax flattened on the ventral surface and merged smoothly with a uniformly thick and squat abdomen and terminated in a pair of divergent lobes. The results obtained indicated that the parasites belong to the sharp-tipped posterior-hook Raillietiella spp. distinguished from other raillietiedids of the same group some important characteristic fea- tures including annulus number, shape and dimensions of the buccal cadre, copulatory spicules, and anterior and posterior hooks. The anterior hook of the female specimens (n = 5) had a blade length (AB) of 135±5 (110-146) ^m and shank length (BC) 158±5 (150-169) ^m while the posterior hook was much larger with AB measuring 221 ±5 (200-236) m and BC 286 ±6 (280-289) -o.m. For the male specimens (n = 5), the anterior hook had an AB of 73 ±3 (72-75) -j.m and a BC 102±5 (100-103) ^m. The posterior hook was much larger with AB 190.6±5 (190-191).


Resumen En el presente estudio se aisló un pentastómido perteneciente al orden Cephalobaenida del pulmón de un eslizón bereber (Eumeces schneideri, Familia: Scincidae). Se efectuó su descripción morfológica basada en observación por microscopía óptica y de bar rido y se justificó su ubicación taxonómica mediante análisis molecular del gen 18S del ADNr. Se recolectaron 17 especímenes del citado huésped en valles ubicados a elevadas altitudes, en la región de Jizan (Arabia Saudí); 12 de ellos (70,59%) estaban infectados. Todos los parásitos recuperados eran adultos y poseían un pequeño cefalotórax triangular, aplanado en la super ficie ventral, que se fusionaba con un abdomen abultado y terminado en un par de lóbulos divergentes. Los resultados indicaron que este parásito pertenece a Raillietiella spp., que agrupa especies con gancho posterior puntiagudo; estas se distinguen de otros miembros de la Familia Raillietiella por algunos rasgos característicos, como el número de anillos y la forma y dimensiones del cuadro bucal, las espículas copulatorias y los ganchos anterior y posterior. La caracterización morfológica demostró que el parásito recuperado era muy similar a R. aegypti, previamente aislada del mismo huésped. El alineamiento de secuencias mediante el método de probabilidad máxima basado en el análisis del gen 18s del ADNr detectó identidades del 88-95% con los géneros de pentastómidos disponibles en GenBank. Dentro del árbol filogenético se pudo incluir este parásito dentro del clado monofilético pentastómido con máxima identidad con las especies de Raillietiella. Las secuencias obtenidas fueron depositadas en GenBank, con número de acceso MK970649.1. El presente análisis molecular confirma por primera vez la posición taxonómica de Raillietiella aegypti, anteriormente aislado del mismo huésped.


Assuntos
Animais , Feminino , Masculino , Pentastomídeos , Lagartos , Filogenia , DNA Ribossômico/genética , Pentastomídeos/genética , Lagartos/genética , Pulmão
2.
Rev. biol. trop ; 61(1): 255-262, Mar. 2013. graf
Artigo em Inglês | LILACS | ID: lil-674077

RESUMO

Variation in body characteristics related to lizard locomotion has been poorly studied at the intraspecific level in Anolis species. Local adaptation due to habitat heterogeneity has been reported in some island species. However, studies of mainland species are particularly scarce and suggest different patterns: high variability among highland lizards and poorly differentiated populations in one Amazonian species. We characterized inter population variation of body size and shape in the highland Andean Anolis ventrimaculatus, an endemic species from Western Colombia. A total of 15 morphometric variables were measured in specimens from the reptile collection of the Instituto de Ciencias Naturales, Universidad Nacional, Colombia. The study included individuals from seven different highland localities. We found size and shape sexual dimorphism, both of which varied among localities. Patterns of variation in body proportions among populations were different in both males and females, suggesting that either sexual or natural selective factors are different in each locality and between sexes. Since this species exhibits a fragmented distribution in highlands, genetic divergence may also be a causal factor of the observed variation. Ecological, behavioral, additional morphological as well as phylogenetic data, may help to understand the evolutionary processes behind the geographic patterns found in this species.


La diversificación fenotípica al interior de una especie en características de dimensiones corporales relacionadas con la locomoción de los lagartos, se ha estudiado poco en especies de Anolis. Los datos de algunas especies de isla revelan patrones distintos de variación geográfica y sugieren que la adaptación local, debida a la heterogeneidad del hábitat, ocurre a este nivel. Los estudios de especies de continente son particularmente escasos y sugieren patrones distintos: un lagarto altoandino altamente variable y poblaciones poco diferenciadas en una especie amazónica. Caracterizamos la variación inter poblacional en el tamaño y forma del cuerpo del lagarto altoandino Anolis ventrimaculatus, especie endémica del Oeste de Colombia. Encontramos variación geográfica en el dimorfismo sexual en tamaño y forma. El patrón de variación en las proporciones corporales entre poblaciones fue distinto en machos y en hembras, sugiriendo que las presiones de selección sexual o natural son diferentes en cada localidad. Dado que la especie exhibe una distribución fragmentada en alta montaña, la divergencia genética entre poblaciones puede ser otro factor causal de la variación observada. Datos ecológicos, etológicos y morfológicos adicionales, así como información filogenética puede contribuir al entendimiento de los procesos evolutivos responsables del patrón de variación geográfica encontrado en esta especie.


Assuntos
Animais , Feminino , Masculino , Tamanho Corporal/genética , Variação Genética , Lagartos/anatomia & histologia , Caracteres Sexuais , Lagartos/classificação , Lagartos/genética , Fenótipo , Filogenia , Somatotipos , Especificidade da Espécie
3.
Genet. mol. biol ; 34(4): 583-586, 2011. ilus
Artigo em Inglês | LILACS | ID: lil-605941

RESUMO

Chromosomal mapping of the butterfly lizards Leiolepis belliana belliana and L. boehmei was done using the 18S-28S and 5S rRNA genes and telomeric (TTAGGG)n sequences. The karyotype of L. b. belliana was 2n = 36, whereas that of L. boehmei was 2n = 34. The 18S-28S rRNA genes were located at the secondary constriction of the long arm of chromosome 1, while the 5S rRNA genes were found in the pericentromeric region of chromosome 6 in both species. Hybridization signals for the (TTAGGG)n sequence were observed at the telomeric ends of all chromosomes, as well as interstitially at the same position as the 18S-28S rRNA genes in L. boehmei. This finding suggests that in L. boehmei telomere-to-telomere fusion probably occurred between chromosome 1 and a microchromosome where the 18S-28S rRNA genes were located or, alternatively, at the secondary constriction of chromosome 1. The absence of telomeric sequence signals in chromosome 1 of L. b. belliana suggested that its chromosomes may have only a few copies of the (TTAGGG)n sequence or that there may have been a gradual loss of the repeat sequences during chromosomal evolution.


Assuntos
Animais , Lagartos/genética , RNA Ribossômico 18S , RNA Ribossômico 5S , Mapeamento Cromossômico , Hibridização in Situ Fluorescente , Telômero
4.
Rev. biol. trop ; 56(4): 1871-1881, Dec. 2008. graf, tab
Artigo em Espanhol | LILACS | ID: lil-637784

RESUMO

Morphologic variation of the parthenogenetic lizard Aspidoscelis rodecki (Squamata: Teiidae): evolutionary and conservation implications. Post-formational divergence has been used for the recognition of new parthenogenetic species. Currently, the parthenogenetic lizard Aspidoscelis rodecki McCoy and Maslin 1962 is recognized as a single taxon that was derived from a single, parthenogenetically capable, hybrid. This lizard had been derived via hybridization between individuals of two gonochoristic species, Aspidoscelis angusticeps Cope 1878 and Aspidoscelis deppii Wiegmann 1834. The distribution of A. rodecki includes Isla Contoy and Isla Mujeres and the adjacent mainland of Quintana Roo, México. Previous studies have found post-formational divergence in genetic, chromatic and life-history characteristics among a continental population (Puerto Juárez) and an insular population (Isla Contoy). A meristic analysis was carried out to evaluate the morphological divergence among both populations of A. rodecki. We used 38 individuals from Puerto Juárez and 23 individuals from Isla Contoy. Nine meristic characters with discrimination value among species of the genus Aspidoscelis were used in both univariate (t-Student) and multivariate analyses (principal components and canonical variate analysis). According to both analyses, Puerto Juárez is meristically distinguishable from Isla Contoy. Both populations differ in five meristic characters and were a high correct classification in the canonical variate analysis: 97% of Puerto Juárez and 100% of Isla Contoy. A small sample from Isla Mujeres and a single specimen from Punta Sam (mainland) may represent different morphological groups. Due to the patterns of phenotypic variation, A. rodecki is considered as a single variable parthenogenetic species with high priority to conservation. The populations of A. rodecki have been extremely affected by the tourism developers. If the habitat of the parthenogenetic lizard (beach grasses) is allowed to stay, the expansion by the developers will not affect the survivorship of these populations. Nevertheless, the first sign of development is the total destruction of natural grasses that occurs on the beach, leaving only sand. There is a last chance to save the parthenogenetic lizard A. rodecki, but any effort will be useless without the support from the environmental authority of Mexico and cooperation from the developers. We suggest that Puerto Juárez and Isla Contoy receive separate management because they have unique portions of phenotypic variation of A. rodecki. The two lizard populations can be considered separate "Evolutionary Significant Units" (ESU). Rev. Biol. Trop. 56 (4): 1871-1881. Epub 2008 December 12.


La divergencia post-formación se ha utilizado para el reconocimiento de nuevas especies partenogenéticas. Actualmente, la lagartija partenogenética Aspidoscelis rodecki McCoy y Maslin 1962 es reconocida como una sola especie, que se originó de un híbrido partenogenético. Estudios previos han encontrado divergencia genética, en coloración y en características de historia de vida entre una población continental (Puerto Juárez) y una insular (Isla Contoy) en Quintana Roo, México. Se llevó a cabo un análisis merístico para evaluar la divergencia entre ambas poblaciones de A. rodecki. Se utilizaron 38 individuos de Puerto Juárez y 23 individuos de Isla Contoy. Se usaron nueve características merísticas y se realizaron análisis univariados (t de Student) y multivariados (análisis de componentes principales y análisis de variación canónica). De acuerdo a ambos análisis, Puerto Juárez es merísticamente distinguible de Isla Contoy. Ambas poblaciones difieren en cinco características merísticas y presentaron un alto porcentaje de clasificación en el análisis de variación canónica: 97% para Puerto Juárez y 100% para Isla Contoy. Una pequeña muestra de Isla Mujeres y un solo individuo de Punta Sam (continente) pueden representar otros grupos morfológicos. Con base en los patrones de variación fenotípica, A. rodecki es considerada como una sola especie partenogenética variable y prioritaria para la conservación. Debido a que cada población contiene una porción única de la variación de A. rodecki, Puerto Juárez e Isla Contoy merecen un manejo separado y se sugiere que cada una constituya una "Unidad Evolutiva Significativa" (ESU).


Assuntos
Animais , Feminino , Lagartos/genética , Partenogênese/genética , Evolução Molecular , Lagartos/anatomia & histologia , Lagartos/classificação , México , Fenótipo
5.
J Biosci ; 2007 Apr; 32(3): 489-99
Artigo em Inglês | IMSEAR | ID: sea-110744

RESUMO

For many years,we and our collaborators have investigated the adaptive role of heat shock proteins in different animals,including the representatives of homothermic and poikilothermic species that inhabit regions with contrasting thermal conditions. Adaptive evolution of the response to hyperthermia has led to different results depending upon the species. The thermal threshold of induction of heat shock proteins in desert thermophylic species is, as a rule, higher than in the species from less extreme climates.In addition,thermoresistant poikilothermic species often exhibit a certain level of heat shock proteins in cells even at a physiologically normal temperature. Furthermore,there is often a positive correlation between the characteristic temperature of the ecological niche of a given species and the amount of Hsp70-like proteins in the cells at normal temperature. Although in most cases adaptation to hyperthermia occurs without changes in the number of heat shock genes, these genes can be amplified in some xeric species. It was shown that mobile genetic elements may play an important role in the evolution and fine-tuning of the heat shock response system,and can be used for direct introduction of mutations in the promoter regions of these genes.


Assuntos
Aclimatação/fisiologia , Animais , Clima Desértico , Drosophila/genética , Ecossistema , Evolução Biológica , Proteínas de Choque Térmico/metabolismo , Lagartos/genética , Mariposas/genética , Regiões Promotoras Genéticas/genética , Temperatura
6.
Genet. mol. biol ; 29(3): 576-579, 2006. tab
Artigo em Inglês | LILACS | ID: lil-450302

RESUMO

The Sox family of genes shares a high sequence similarity with the HMG box region of the human Y chromosomal gene, SRY. We used highly degenerate primers to clone and sequence seven Eremias breuchleyi Sox genes (EbSox2, EbSox3, EbSox4, EbSox11, EbSox12, EbSox14 and EbSox21). A database search for the cloned sequences revealed the following percentage identity with the homologous human SOX genes: EbSox2 = 96 percent, EbSox3 = 88 percent, EbSox4 = 94 percent, EbSox11 = 99 percent, EbSox12 = 96 percent, EbSox14 = 98 percent, EbSox21 = 97 percent. Cluster analysis indicates that they seem to belong to group B and group C of Sox gene family, respectively.


Assuntos
Animais , Proteínas de Grupo de Alta Mobilidade , Lagartos/genética , Análise de Sequência , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteína da Região Y Determinante do Sexo
7.
Rev. bras. genét ; 17(4): 401-8, dez. 1994. ilus, tab
Artigo em Inglês | LILACS | ID: lil-164710

RESUMO

Cytogenetic studies were performed on six tropidurid lizards: Tropidurus mucujensis, T hispidus, T montanus, T semitaeniatus, T spinulosus and Uranoscodon superciliosus. Conventional and differential (C- and R-bands and Ag-NORs) staining techniques were employed for the characterization of the karyotypes. The analyses were carried out in order to establish the morphological characterization of macro and microchromosomes, the R- and C-banding patterns as well as the silver staining of nucleolus organizer regions (Ag-NORs). R-banding was obtained after in vitro incorporation of 5-bromodeoxyuridine (BrdU). For some species, the banding patterns are described for the first time. All species presented a diploid number of 2n=36, with a basic karyotype constituted by 12 metacentric or submetacentric macrochromosomes and 24 microchromosomes (12M+24m). Although these species present a conservative karyotype, most of them are distinguished by the morphology of the macro and microchromosomes, by location of Ag-NORs, and by amount and distribution of constitutive hetcrochromatin. Sex determination of the XX:XY type was found in T hispidus, T montanusand U. superciliosus. The presence of species specific karyotypes in T spinulosus and U. superciliosus is suggested.


Assuntos
Animais , Masculino , Feminino , Cromossomos , Lagartos/genética , Argentina , Brasil , Coloração e Rotulagem , Cariotipagem , Metáfase
8.
Rev. bras. genét ; 12(4): 747-59, dic. 1989. ilus, tab
Artigo em Inglês | LILACS | ID: lil-94216

RESUMO

Uma populaçäo relativamente densa de Strobilurus torquatus foi encontrada em Säo José, próximo à Itabuna, Estado da Bahia, na Mata Atlântica do Brasil. Este lagarto, aparentemente raro, é um heliófilo de floresta e se alimenta de formigas que obtem em vários níveis nos troncos das grandes árvores e ocasionalmente, no chäo. O dimorfismo sexual é aparente no comprimento rostro-anal e da tíbia: os machos possuem tíbias mais longas e grossas do que as fêmeas. As fêmeas grávidas têm ninhadas de 2 a 3 ovos. Os estudos citogenéticos mostraram 2n = 36 cromossomos, caracterizados por 12 macrocromossomos e 24 microcromossomos e um mecanismo de determinaçäo do sexo XX:XY. Também säo apresentados por padröes de bandas C, localizaçäo das regiöes organizadoras de nucléolo, bandas R após tratamento in vivo com 5-bromodeoxiuridina (5-BrdU) e dados meióticos de machos


Assuntos
Citogenética , Cariotipagem , Lagartos/genética , Brasil , Caracteres Sexuais , Ecologia , Região Organizadora do Nucléolo
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