Giovany Guevara

University of Tolima | UT · Departamento de Biología

The wandering spider, Phoneutria depilata, is one of Colombia’s most active nocturnal arthropod predators of vertebrates and invertebrates. Its venom has been a relevant subject of study in the last two decades. However, the scarcity of transcriptomic data for the species limits our knowledge of the distinct components present in its venom for link...

Los cangrejos de montaña (Decapoda: Pseudothelphusidae) son considerados sensibles a diversas alteraciones antropogénicas y ambientales en los ecosistemas acuáticos. En quebradas de la región andina colombiana, que drenan varios agroecosistemas, existe poca información sobre estos organismos. Aquí se muestran los resultados de la abundancia de Hypo...

El funcionamiento ecosistémico de quebradas o arroyos altoandinos de Colombia aún es poco conocido. El objetivo de este estudio fue evaluar la descomposición de hojas de aliso (Alnus acuminata), sietecueros (Andesanthus lepidotus) y una mezcla 1:1 de estas especies (Mixto), utilizando bolsas de hojarasca de poro amplio y fino, de 5 y 0,5 mm respect...

La cuenca del río Amoyá, ubicada en el municipio de Chaparral dentro del gran Cañón de las Hermosas, constituye una de las más importantes del suroccidente del Tolima. A pesar de que actualmente sabemos que cuenta con una gran riqueza en términos biológicos, culturales e históricos, distintos procesos de movilización social habían condicionado la g...

Plant–animal interactions constitute some of the most important ecological processes for the maintenance of tropical forests. Bats are the only group of mammals capable of true flight and have been recognized as important dispersers of pioneer and secondary successional plant species. Although progress has been made in the study of Neotropical bats...

Entomological collections represent a key source of information about the biological heritage of a country. However, the taxonomy and knowledge of many arthropods from megadiverse countries are underrepresented in these natural history collections as is the case with several planthoppers of the suborder Auchenorrhyncha. Issidae are fulgoromorphs di...

Los cangrejos de agua dulce (Decapoda: Pseudothelphusidae) son un grupo de invertebrados clave en los ecosistemas montanos de Colombia; participan en el reciclaje de la materia orgánica, son eslabones intermedios de las cadenas tróficas, y son sensibles a las perturbaciones antropogénicas. Los pocos estudios en el departamento de Caldas se han enfo...

Desde el inicio de la pandemia por COVID-19, las instituciones académicas de todo el mundo se vieron obligadas a cerrar sus campus y ajustar su enseñanza a un modelo de educación a distancia. Una de las actividades de mayor dificultad estuvo relacionada con las prácticas de laboratorio, que no pueden cubrirse adecuadamente utilizando solo computado...

The study of human relationships with other components of the landscape allows us to understand the dynamics of ecological communities and biodiversity. Although there has been an increase in ethnobiological studies, little is known about the interaction between humans and bats. The objective of this study was to evaluate the perceptions and attitu...

In Neotropical bats, studies on bite force have focused mainly on differences in trophic ecology, and little is known about whether factors other than body size generate interspecific differences in bite force amongst insectivorous bats and, consequently, in their diets. We tested if bite force is related to skull morphology and also to diet in an...

• Bats in the family Phyllostomidae exhibit great diversity in skull size and morphology that reflects the degree of resource division and ecological overlap in the group. In particular, the subfamily Stenodermatinae has high morphological diversification associated with cranial and mandibular traits that are associated with the ability to consume...

Objetivo. Proporcionar información sobre el ciclo de vida del psílido de la concha (o del escudo), Glycaspis brimblecombei en Colombia, y sus enemigos naturales, principalmente la avispa parasitaria Psyllaephagus bliteus, en una plantación de eucalipto en Jericó (Antioquia). Alcance. A través de ensayos experimentales, se muestran los resultados d...

Bats play crucial ecosystem services as seed dispersers, pollinators, controllers of insect, and nutrient recyclers. However, there has not been a thorough global review evaluating these roles in bats across all biogeographical regions of the world. We reviewed the literature published during the last two decades and identified 283 relevant studies...

Arachnids are the most abundant land predators. Despite the importance of their functional roles as predators and the necessity to understand their diet for conservation, the trophic ecology of many arachnid species has not been sufficiently studied. In the case of the wandering spider, Phoneutria boliviensis F. O. Pickard‐Cambridge, 1897, only fie...

1. Phyllostomid bats exhibit great diversity in skull size and morphology that reflects the degree of resource division and ecological overlap in the group. In particular, Stenodermatinae has high morphological diversification associated with cranial and mandibular traits that is associated with the ability to consume the full range of available fr...

Background Mining, agriculture and cattle production are activities that threaten the quality and quantity of water resources in the Colombian Andes. However, many drainage basins in this region have not been subjected to simultaneous evaluation of the impact these activities have on the density, diversity and composition of aquatic macroinvertebra...

Introduction: The Neotropical Otter, Lontra longicaudis, is a semi-aquatic mammal that ranges from Mexico to Argentina inhabiting near-pristine watercourses, but also human-dominated aquatic and riparian landscapes. Objective: We assessed the distribution and habitat use frequency of L. longicaudis in La Miel I hydroelectric power dam and its infl...

El objetivo de este estudio fue evaluar la colonización de macroinvertebrados y el porcentaje de pérdida de masa seca de hojas de Eucalyptus sp. y Tibouchina lepidota en una quebrada afectada por la actividad minera ubicada en la parte alta de la cuenca del río Chinchiná (Manizales, Colombia). Se seleccionaron dos áreas de muestreo: una reconocida...

El orden Plecoptera representa uno de los grupos de insectos más relevantes en bioindicación en Colombia. En los últimos años su conocimiento ha aumentado ampliamente; no obstante, en algunas zonas de la región andina, los estudios taxonómicos y ecológicos son aún incipientes. Dada la importancia de los plecópteros en quebradas de alta montaña, se...

Phoneutria Perty, 1833 is considered one of the most toxic spider genera in the world; however, the natural history and biology of these spiders is still largely unexplored. The objective of this study was to determine the natural diet of the medically important species Phoneutria boliviensis (F.O.P.-Cambridge, 1897) based on prey records from Colo...

Here, we have presented a field device for sampling periphyton in lentic systems, with a tropical lowland wetland in Colombia as the model system. The periphyton sampler (PS) is composed of a central soft iron pole to which rectangular woody boxes and glass slides are attached to lateral iron axes, which can be distributed at different depths. Our...

Background: Behavior and activity patterns largely determine animal's fitness and their ecological roles. Those patterns depend on many factors, being body mass, sex and age the most relevant in mammals. Particularly, those factors altogether with environmental conditions could influence movement behavior of mammals that hibernate, such as the Moni...

Morphological differences between the sexes are a common feature in many groups of animals and can have important ecological implications for courtship, mating, access to prey and, in some cases, intersex niche partitioning. In this study, we evaluated the role of sexual dimorphism in the performance of the two structures that mediate the ability t...

Morphological differences between the sexes are a common feature in many groups of animals and can have important ecological implications for courtship, mating, access to prey and, in some cases, intersex niche partitioning. In this study, we evaluated the role of sexual dimorphism in the performance of the two structures that mediate the ability t...

Spiders rely on venom to catch prey and few species are even capable of capturing vertebrates. The majority of spiders are generalist predators, possessing complex venom, in which different toxins seem to target different types of prey. In this study, we focused on the trophic ecology and venom toxicity of Phoneutria boliviensis F. O. Pickard-Cambr...

Planted forests are becoming increasingly common worldwide, replacing natural forests and compromising their associated biodiversity. However, not all forest plantations are the same. Aiming to identify key plantation features that could be managed to improve bird diversity, we conducted a meta-analysis examining the differential effects of several...

This paper describes the Photafish System, an innovative technique for capturing high-quality digital images of live freshwater fishes and other aquatic organisms in the field. This system may improve and facilitate the visual documentation of such organisms to illustrate guidebooks, populate online databases and support scientific papers, particul...

Resumen Objetivo: Demostrar la interacción hombre-fauna silvestre a través de dos reportes de tenencia de fauna silvestre como mascota en un río colombiano. Alcance: Se reportan dos casos de interacción (como mascota) entre el hombre y la nutria neotropical (Lontra longicaudis Olfers, 1818) en dos tributarios de la cuenca del río Magdalena (Villavi...

The Black-and-chestnut Eagle (Spizaetus isidori) is one of the least known Neotropical birds of prey, with scarce information about its basic biology throughout its entire distribution range. Information on the duration of its parental dependence is inexistent, although this is a key period in the natural history of birds which will impact the subs...

Headwater streams are fully linked to surrounding riparian vegetation through coarse and fine organic matter inputs. However, forestry operations in or close to riparian corridors, particularly in mountainous forested microcatchments, can alter both the organic matter dynamics and the composition, structure and function of stream macroinvertebrate...

The high levels of biodiversity reported in Colombia are supported by its rich flora and fauna of the Andean region which includes both strategic ecosystems and the most vulnerable to the impact of habitat fragmentation. To counteract these effects, alternatives are proposed for the maintenance of such biotic richness through protected areas. Howev...

Antecedentes. El flujo de nutrientes en arroyos de bajo orden tanto en regiones templadas como tropicales, depende de las ramas y hojas procedentes de su vegetación ribereña. Este sustrato sufre descomposición física, química y biológica y puede ser colonizado por varios macroinvertebrados bentónicos. Sin embargo, el efecto de diferentes niveles de...

Los andes colombianos han sido modificados por la actividad humana, dando como resultado un paisaje dominado por agroecosistemas. Los lepidópteros son indicadores de diversidad y ecológicamente útiles para comprender los cambios en las coberturas vegetales mediante la variación en la estructura y composición de sus ensamblajes. El objetivo de este...

POPULAR KNOWLEDGE AND CONSERVATION PERSPECTIVES ON THE INLAND TURTLES AT THE LOWER PART OF LA MIEL RIVER (COLOMBIA) The lower part of La Miel River, located at the north-east of the Department of Caldas, hosts five Colombian inland turtle species. Information about knowledge and turtles’ use (for food, trade, or pets) was recorded using a semi-str...

La materia orgánica alóctona es la mayor fuente de energía en ecosistemas dulceacuícolas, especialmente en quebradas de cabecera donde la producción primaria es baja y limitada por la vegetación de ribera. La materia orgánica entra a los ríos y quebradas donde es aprovechada por los invertebrados quienes se alimentan de esta y contribuyen a su desc...

Introducción. En los ecosistemas acuáticos de alta montaña, el aporte y retención de hojarasca alóctona constituyen eventos ecológicos relevantes en la dinámica de nutrientes. Problema. Sin embargo, en sistemas acuáticos altoandinos de Colombia, existe poca información acerca de la importancia de dicho sustrato, y de las ventajas/desventajas de mét...

The planthopper subfamily Asiracinae (Hemiptera: Auchenorrhyncha: Delphacidae) and the species Copicerus irroratus Swartz are reported for the first time for Colombia from an agricultural landscape at the Andean region (Villamaría, Caldas). Relevant diagnostic and biological features of the species are discussed. A key to the species of Copicerus i...

Las alteraciones antropogénicas más frecuentes sobre los ecosistemas acuáticos de la región Andina colombiana, están relacionados con cambios en su vegetación ribereña. Entre los principales impactos, se destacan las actividades ganaderas, agrícolas y mineras en ecosistemas altoandinos, en los cuales su metabolismo interno, depende del aporte de ma...

Resumen Las alteraciones antropogénicas más frecuentes sobre los ecosistemas acuáticos de la región Andina colombiana, están relacionados con cambios en su vegetación ribereña. Entre los principales impactos, se destacan las actividades ganaderas, agrícolas y mineras en ecosistemas altoandinos, en los cuales su metabolismo interno, depende del apor...

We assessed the effect of forest management practices on temporal differences in riparian litterfall input and autumnal leaf litter processing of 3 evergreen plant species, using independently 2 mesh sizes (for two of the three species), between two contrasting headwater streams draining (a) near-pristine and (b) harvested evergreen old-growth fore...

ESTUDIO DE LA INTERACCIÓN HUMANO-ÁGUILA CRESTADA Spizaetus isidori EN EL ÁREA DE INFLUENCIA DE LOS FARALLONES DE GACHALÁ Y MEDINA, CUNDINAMARCA ---------------------------------------------------------------------------------------------------------------------- Spizaetus isidori se encuentra actualmente categorizada como "En peligro", En la actual...

En ecosistemas de alta montaña la descomposición de hojarasca constituye uno de los aspectos ecológicos más importantes en la dinámica de la materia orgánica y flujo de nutrientes. Debido a la importancia de este componente orgánico, este trabajo busca evaluar las tasas de descomposición de hojarasca de especies andinas poco investigadas, Cecropia...

Although mangroves are recognized worldwide as highly productive and ecologically important ecosystems , at present its extent has been significantly reduced due to human activities in coastal areas. Therefore, it is necessary to investigate their dynamics and responses under the growing and sustained climatic and anthropogenic impacts. During two...

Los ríos de bosques secos tropicales están amenazados en todo el mundo, y en Suramérica son una de las prioridades en términos de conservación. En este estudio se determinó la influencia de variables ambientales (por ejemplo precipitación) y la vegetación ribereña sobre las comunidades del orden Trichoptera en cuatro sustratos (roca, grava, arena y...

In Colombia many rivers and other inland aquatic systems, especially into the Andean Region (the most populated of the country), suffer several anthropogenic impacts related to land use and land cover compromising their water quality and quantity, and the provision of other goods and ecosystem services for the future. It is imperative that the Colo...

In two watersheds with riparian vegetation typical of tropical dry forest in the department of Tolima (Opia and Venadillo rivers), the composition, structure and richness of Trichoptera larvae during a hydrological cycle, and its relation to rainfall and land use (agriculture and urbanization) were assessed. In each river, we selected two 100 m sec...

Non-invasive methodological approaches are highly recommended and commonly used to study the feeding ecology of elusive and threatened mammals. In this study, we use multiple lines of evidence to assess the feeding strategies of the endangered Southern river otter, by determining seasonal prey availability (electrofishing), analysis of undigested p...

Total body length and head capsule width (mm) were used as biometric characteristics in discriminating between size-frequency estimates of three Anacroneuria morphospecies, from 28 sampling sites along a tropical river subject to bimodal variations in water level in Central Colombia. A total of 344 specimens grouped into four size classes were coll...

Between February and May 2007, the trichopteran fauna of the Totare River basin (Tolima) was studied. Twenty-seven stations were established between 244 and 2397 meters a.s.l. A total of 3593 specimens belonging to 11 families and 26 genera were collected. The family Xiphocentronidae (Xiphocentron) and the following genera are reported for the firs...

A rapid survey for assessing the composition and structure of a bat community present in a semi-urban ecological park, Northwestern Colombia, was carried out from March to May 2005. Five biotopes: wetland, secondary rain forest, wetland, acacia plantation and pasture were assessed, totaling 368 hours/net. We collected 17 bat species belonging to fi...

En el corazón de Colombia late una tierra bañada por el rio Magdalena, vigilada por la diosa Tulima, que en términos indígenas invoca una divinidad protectora de su territorio; una tierra rodeada por imponentes nevados, donde el verde del paisaje andino se une en el lejano horizonte con el azul profundo del cielo. Una tierra privilegiada por su ini...

Zooplankton community analyses can reveal valuable information about the trophic status and secondary production in reservoirs. The zooplankton seasonal distribution and important physical and chemical parameters in Prado Reservoir (Tolima, Central Colombia) were studied in monthly surveys throughout a hydrological cycle (February 2000–January 2001...

Se registran por primera vez para Colombia ninfas pertenecientes al género Needhamella Domínguez y Flowers, 1989 (Leptophlebiidae, Ephemeroptera) en la cuenca del río Prado en el departamento del Tolima. El estudio llevado a cabo en los meses de agosto, septiembre y noviembre de 2004, permitió evidenciar la presencia de 97 ninfas de este género en...

Trichoptera larvae are reported from an Andean basin in the Department of Tolima (Central Colombia). Twenty-six taxa were recorded during four samplings in March, May, July-August and September 2003. Different sampling techniques were used to collect the caddisflies such as hand net, hand inspection and sieves. Twenty-nine sampling stations were es...

Cattleya trianae is an endemic species from the tropical rainforest in the Colombian Andes. Its survival is currently threatened due to habitat loss and commercial overexploitation. This study evaluates ten substrates, some organic (pine bark, coconut fiber and wood shavings), some inert icopor (polystyrene foam), vegetable coal and their combinati...

The composition and abundance of aquatic Coleoptera from the Coello River Basin (Tolima, Colombia) were recorded during March, May, July-August and September 2003. A total of 3071 specimens belonging to two suborders, ten families and 27 genera were collected. Genera such as Copelatus, Andogyrus, Hexacylloepus, Hexanchorus, Neocylloepus, Promoresia...

Se realizó un estudio en la cuenca mayor del Río Prado (Tolima) entre los 289 y 2257msnm, para evaluar la composición taxonómica y aspectos ecológicos de las ninfas de la familia Baetidae (Ephemeroptera: Insecta); durante los meses de Agosto, Septiembre y Noviembre de 2004. Se determinó la diversidad, distribución, abundancia, dominancia y frecuenc...

As result of recent studies of Colombian insects, one species of Gripopterygidae is cited for the first time for Colombia.

RESUMEN En noviembre de 2005 se comparó la abundancia y diversidad taxonómica de los estados preimaginales de los macroinvertebrados en dos arroyos de la Reserva Costera Valdiviana (RCV), en el sur de Chile. Se hizo una evaluación rápida de dos ambientes, uno perturbado (i.e., con plantaciones ribereñas de Eucalyptus spp.) y uno prístino (i.e., bos...