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Vieja hartwegi was described by Taylor and Miller in 1980 based on 45 juvenile and sub-adult specimens, but this species shows an enormous variation in coloration patterns during ontogenic development and between individuals. Additionally, morphological data have demonstrated the existence of two forms in V. hartwegi: the typical morph of a moderately deep to slightly elongated body shape with midlateral band, and a rheophilic morph with an elongated to slightly deep body shape and lack of midlateral band. Herein we redescribe V. hartwegi adding adults and individuals from broad geographic ranges, as well as a rheophilic morph recently discovered in the upper reaches of the Grijalva River basin in Mexico. The set of characters include coloration, meristic, morphometric and osteological features. Vieja hartwegi is a polymorphic species whose forms may be segregating because of habitat preferences and food habits.
Assuntos
Ciclídeos , Animais , Ecossistema , Guatemala , México , RiosRESUMO
Resumen El pez león (Pterois volitans) invadió la región del Caribe y tiene el potencial de alterar la composición y estructura de las comunidades de peces en los arrecifes coralinos. El objetivo de este estudio fue analizar los índices de diversidad en las comunidades de peces nativos en sitios invadidos por el pez león en dos áreas marinas protegidas (AMP) del Caribe y compararlos con datos previos a la invasión. En ambas AMP, Parque Nacional Guanahacabibes (PNG) en el occidente de Cuba y Parque Nacional Arrecifes de Xcalak (PNAX) en el S de Quintana Roo, se realizaron censos visuales de las especies de peces en hábitats durante las épocas de seca y lluvia del 2013-2015. Se evaluaron nueve sitios, mediante conteos estacionarios. Se registró mayor riqueza de especies en el PNG (43.47±5.14) que en el PNAX (40.22±4.96). No se observaron diferencias entre épocas en ninguna de las AMP. El pez león se ubicó entre las especies más abundantes del PNG. La abundancia media en el PNG (0.76 ± 1.25) fue mayor a la registrada en el PNAX (0.19±0.46). La diversidad disminuyó después de la llegada del pez león en un solo sitio del PNG y en dos sitios del PNAX, pero al parecer estos resultados están más asociados al efecto de la pesca que a la presencia del pez león. A partir de los resultados y asumiendo que los cambios en las comunidades de peces por el pez león podrían no detectarse aún, recomendamos seguir los monitoreos de los descriptores comunitarios para detectar cambios futuros en las comunidades de peces.
Abstract Lionfish (Pterois volitans) invaded the Caribbean region with the potential to alter the composition and structure of native coral reef fish communities. The objective of this study was to analyze the diversity indices of these fish communities potentially affected by lionfish predation and to compare with pre-invasion data. The study was undertaken in two Caribbean marine protected areas (MPAs): Guanahacabibes National Park (PNG) in W Cuba and Xcalak Reefs National Park (PNAX) in S Quintana Roo. We carried out visual censuses of fish species in reef habitats during the dry and rainy seasons of the period 2013-2015. For this, nine sites were defined and evaluated using stationary counts. Our results showed higher species richness (43.47 ± 5.14) and mean abundance (0.76 ± 1.25) in PNG than in PNAX (40.22 ± 4.96, 0.19 ± 0.46, respectively). Diversity decreased after the arrival of lionfish in a single site of PNG and in two sites of the PNAX, but apparently, these results are more related to the fishing activity effect than to the lionfish presence. Based on the results and assuming that changes in the native fish communities by lionfish may not yet be detected, we recommend to continue the monitoring community descriptions in order to detect future changes in native fish communities. Rev. Biol. Trop. 66(1): 189-203. Epub 2018 March 01.
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Abstract Aquatic environments face a variety of threats in the Hondo River basin, Southeastern Yucatán Peninsula. Some of these impacts, like pollution by pesticides, may depend on land use and cover. Our objective was to assess the effect of land use/cover using a previously published index of biotic integrity (IBI), based on fishes and designed for shallow streams in the Hondo River basin. Our hypothesis was that land uses that cause deforestation and pollution, such as urbanization, cattle breeding, or sugar cane fields, would be reflected in low IBI values, at least at some spatial scales. The 23 sites originally used in 2008-2009 to estimate by electrofishing the relative abundance and other characteristics of selected fish species and guilds to construct the IBI, were revisited in February 2010, to validate by direct inspection the type of land use/cover suggested by landscape information in digital databases. We analyzed the effect of seven types of land use/cover (agriculture, pasture, human settlements, water bodies, wetlands, forest, and secondary vegetation) on the IBI values, at four spatial scales, i.e., the percent of every land use/cover at progressively larger circles (125, 250, 500, and 1 000 m diameter) centered on the water body where the IBI value was measured. Correlations were established among the percent land/use cover by scale around 23 sites, and with their corresponding IBI values. Then, Student's t tests were calculated to examine significant differences in land use/cover between groups of localities above and below the median IBI value, and Mann-Whitney's U tests were applied to compare IBI values between localities with andwithout a given landscape cover. Agriculture, human settlements, and secondary vegetation correlated negatively with the IBI; forests positively. Differences were significant (p<0.05) for forest (higher in sites with higher IBI values) and human settlements (lower in sites with higher IBI). Of all the landscape categories located in the Hondo River basin, with the exception of pasture, those of anthropogenic origin tended to be detrimental to aquatic biotic integrity.
Resumen Los ambientes acuáticos en la cuenca del río Hondo, sureste de la península de Yucatán, enfrentan diversas amenazas. Algunos de estos impactos, e.g. contaminación por plaguicidas, pueden depender del uso de suelo o cobertura. El objetivo fue evaluar el efecto del uso del suelo/cobertura sobre un índice biótico de integridad (IBI) basado en peces, publicado previamente, diseñado para arroyos someros en esta cuenca. La hipótesis era que los usos del suelo que involucran deforestación y contaminación, entre ellos urbanización, ganadería o cultivo de caña de azúcar, se verían reflejados en valores bajos del IBI, por lo menos a ciertas escalas espaciales. Los 23 sitios usados originalmente para estimar por electropesca la abundancia relativa y otras características de especies y gremios selectos de peces, para construir el IBI, fueron visitados de nuevo en febrero 2010 para validar por inspección directa el tipo de uso del suelo/cobertura sugerido por la información de paisaje en bases de datos digitales. Se analizó el efecto de siete tipos de uso del suelo/cobertura (agricultura, ganadería, asentamientos humanos, cuerpos de agua, humedales, bosque y vegetación secundaria) sobre los valores del IBI, a cuatro escalas espaciales, i.e., el porcentaje de cada uso del suelo/cobertura en círculos progresivamente mayores (125, 250, 500 y 1 000 m de diámetro) centrados en el cuerpo de agua donde se midió el valor del IBI. Los porcentajes de uso del suelo/cobertura por escala se correlacionaron entre sí y con los valores correspondientes del IBI para explorar su asociación; luego, mediante pruebas t de Student se buscaron diferencias significativas en cobertura entre grupos de localidades por encima y por debajo del valor mediano del IBI, así como pruebas U de Mann-Whitney para comparar valores del IBI entre localidades con o sin una cobertura dada. La agricultura, asentamientos humanos y vegetación secundaria mostraron una relación negativa con el IBI, lo cual sugiere un impacto de las actividades humanas sobre la salud de los ecosistemas acuáticos. Las diferencias fueron significativas para el bosque (mayor en sitios con mejor integridad acuática) y los asentamientos humanos (menor en sitios con mayor valor del IBI). De todas las clases paisajísticas en la cuenca del río Hondo, las de origen antrópico, excepto los pastizales para ganadería, tendieron a ser perjudiciales para la integridad biótica acuática.
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A phylogeny is presented for 34 species of Astyanax, 27 of them once included within A. aeneus or A. fasciatus in Central America and Mexico, based on 52 morphological characters (mostly osteological, but also pigmentation and meristics), with three outgroups. Monophyly is not supported for A. aeneus s. lat., as Brazilian species such as A. fasciatus s. str. and others occur also within that clade. There were only five resolved clades, three of them including both Brazilian and Central American species, one purely Nicaraguan, and one for central-northern Mexico and Texas. Coincidence with previous cladistic hypotheses is only partial. The genus Bramocharax Gill is not recovered, and thus confirmed as a synonym of Astyanax Baird & Girard. The findings point at a more complex biogeographic history of the region than usually recognized.
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Characidae/classificação , Characidae/genética , Filogenia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , América Central , Characidae/anatomia & histologia , Characidae/crescimento & desenvolvimento , América do Norte , Tamanho do ÓrgãoRESUMO
INTRODUCTION: Sports and physical activity are major components of a healthy lifestyle. The objective of this study was to analyze the relationship between sport and physical activity and alcohol consumption among adolescent students based on gender. POPULATION AND METHODS: Descriptive, crosssectional, comparative study conducted in adolescent students (aged between 14 and 17 years old) from the Region of Murcia in 2014. Sport and physical activity was assessed using a validated, adapted survey that included both the International Physical Activity Questionnaire and the Monitoring the Future survey. Eleven school facilities from different districts of the Region of Murcia (Spain) participated. RESULTS: Five hundred and sixty-four adolescent students were included. Among boys, 51.8% reported to be regularly active, versus 21.8% of girls. Significant differences were observed in terms of alcohol consumption by gender (31.1% for boys versus 48.2% for girls, p = 0.000). A significant, reverse relationship between sport and physical activity and alcohol consumption was observed among both boys and girls. CONCLUSIONS: The level of sport and physical activity is higher among adolescent boys than girls. Sport and physical activity shows a positive association with a lower level of alcohol consumption among both genders.
INTRODUCCIÓN: La práctica físico-deportiva es un elemento importante de un estilo de vida saludable. El objetivo fue analizar la relación entre la práctica de actividad físico-deportiva y el hábito de consumo de alcohol en adolescentes escolarizados en función del género. POBLACIÓN Y MÉTODOS: Estudio descriptivo, transversal y comparativo realizado en adolescentes escolarizados (de entre 14 y 17 años de edad) de la Región de Murcia en 2014. Se evaluó la práctica de actividad físico-deportiva mediante una encuesta adaptada y validad que incluyó el International Physical Activity Questionnaire y Monitoring the Future. Participó un total de 11 centros escolares de diferentes localidades de la Región de Murcia (España). RESULTADOS: Se incluyeron 564 adolescentes escolarizados. El 51,8% de los varones se consideraron regularmente activos frente al 21,8% de las mujeres. El consumo de alcohol mostró diferencias significativas en función del género (31,1% en varones y 48,2% en mujeres, p= 0,000). Se encontró una relación inversa y significativa entre la práctica físico-deportiva y el consumo de alcohol en ambos géneros. CONCLUSIONES: Los adolescentes presentan un mayor nivel de práctica físico-deportiva que las mujeres. La práctica de actividad físico-deportiva se asocia positivamente a un menor consumo de alcohol en ambos géneros.
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Consumo de Bebidas Alcoólicas/epidemiologia , Exercício Físico , Esportes , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Espanha/epidemiologia , Estudantes , Inquéritos e QuestionáriosRESUMO
An Index of Biotic Integrity (IBI) is proposed, based on the fish communities and populations in streams of the Hondo River basin, Mexico-Belize. Freshwater environments in this area are threatened by exotic fishes, eutrophication, and pesticide pollution, among other problems. This IBI should allow to identify the most vulnerable sites and eventually guide rehabilitation efforts. Data on composition, structure, and function of fish communities were evaluated. Twenty-three sites in the Mexican part of the basin were explored; a stratified sample of 13 sites was used to design the IBI, and the rest were used to test and refine the index. Thirty-four candidate indicator metrics were scanned for their correlation with an index of water and habitat quality (IWHQ), as well as for the possible influence of stream width and altitude or distance to the Hondo River mainstem. Twelve variables were selected to constitute the IBI: relative abundances of Astyanax aeneus, 'Cichlasoma' urophthalmus, Poecilia mexicana, Poecilia sp. (a new species, probably endemic to the upper Hondo River basin), Xiphophorus hellerii, and X. maculatus; relative abundances of bentholimnetic, herbivore, and sensitive species; percentage of native and tolerant species; and Pielou's evenness index. Most of the sites have a low-medium quality and integrity, showing impact due to partial channelization or to suboptimal water quality, reflected in scarcity or absence of sensitive species, frequent excess of tolerant species, occasional presence of exotics, dominance of herbivores (perhaps due to proliferation of filamentous algae), or dominance of the opportunistic species P. mexicana. The streams with better water and habitat quality are those farthest away from the river mainstem, probably because of lower human population and economical production.