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Por: Diego Esteban Martínez-Revelo | Fecha: 2016

We report the presence of several dung beetle species (Coleoptera: Scarabaeidae: Scarabaeinae) in the Paramos located in Nariño, Colombia, based on the revision of museums specimens, field work and available literature. 210 specimens from three national museums and 362 individuals from collecting trips done by the Nariño University, GAICA Association and the authors were studied. A total of eight species from seven genera and 21 localities were listed. Uroxys elongatus Harold, 1868 is the species with most individuals collected or found in collections. Only one individual of Ontherus brevicollis Kirsch, 1871 and Oruscatus opalescens Bates, 1870 was found. The altitudinal range under study goes from 2800 to 3700 meters, corresponding to the highest altitude reported for U. elongatus, additionally we report the localities for two species, O. opalescens and Dichotomius monstrosus (Harold, 1875), with few or no confirmed data, increasing the knowledge for these species for Colombia.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Miguel Moreno-Palacios | Fecha: 2016

El complejo de páramos Chilí-Barragán es uno de las regiones paramunas de menor extensión en la cordillera Central de Colombia, que se encuentra principalmente sobre el departamento de Tolima. Aunque existen estudios sobre la avifauna asociada a las zonas de páramo del departamento, subsisten vacíos de información sobre este y otros complejos en la región. El objetivo de este estudio fue valuar la diversidad de aves del complejo Chilí-Barragán, a través del estudio de tres de sus páramos, examinando brevemente la dinámica de la avifauna en el gradiente de elevación. Para tal fin se realizaron muestreos en los páramos de Anaime (Cajamarca), Chilí (Roncesvalles) y Las Nieves-Estambul (Ibagué) empleando métodos como registros visuales, auditivos y redes de niebla. Se diseñó un transecto altitudinal desde 3200 – 3600 m s.n.m. con intervalos de 100 m de altura entre cada estación para cada páramo. Como resultado se registraron 89 especies de aves, que representan el 88 % - 96 % de la riqueza de aves estimada para el complejo, información que coloca a esta región paramuna entre las más diversas del país. Adicionalmente, se observó una disminución en la riqueza con el ascenso en el gradiente de elevación y se halló que la avifauna en estos tres páramos presenta una composición diferente entre las franjas altitudinales 3200-3400 m s.n.m. y 3500-3600 m s.n.m.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros
Aves

Por: Julián Andrés Rojas-Morales | Fecha: 2016

Based on specimens housed in a scientific collection, besides literature and field observations, we present an updated list of the herpetofauna of the south-central region of Caldas, Colombia. The composition of anurans, lizards and snakes was compared with other Colombian assemblages. In addition, all species were categorized according to the extent of its distribution range. A total of 36 amphibians (35 anurans and one salamander) and 38 reptiles (15 lizards, 22 snakes and one turtle) are currently known for the south-central region of Caldas. Comparisons of the amphibians and reptiles assemblages showed low and moderate values (Coefficient of biogeographic resemblance, range = 0.018–0.440, X̅ = 0.152), indicating that about frogs, lizards, snakes, and overall herpetofauna, the south-central region of Caldas is more akin to the Yotoco Forestal Reserve (0.326, 0.421, 0.585, 0.440, respectively). Regarding geographical distribution patterns, six species (8.1%) are endemic to the Northern region of the Cordillera Central, 40 species (54%) correspond to elements of an Andean-tropical fauna, 14 species (18.9%) are distributed from Central America to the Andes, and eight species (10.8%) have a wide distribution throughout the continent.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Silvia Galván-Guevara | Fecha: 2016

The present work characterized the current fragmentation of the relictual tropical forest dry of the Pechelín stream drainge, in Montes de María, Colombian Caribbean. The selection and calculation of cover and size of the forest fragments was done using satellite images and geographical information systems. The degree of fragmentation, spatial continuity and Patton form diversity index were calculated. The average area of the patches was 16.08 ha (Max. 149.8 ha and Min. 0.17 ha). The perimeter average was 2979.99 m2 (Max. 12475.76 m2 and Min. 4334.98 m2). The average patch size is small so that probably affects the ecological stability of the study area due to microclimate changes. The obtained data show that fragmentation exists in the forest of the study area. According to the degree of fragmentation index (F = 0.355), the forest area is in the insular category, with a continuity index of 3.98, or discontinuous. As for shape, the most common was irregular (41.7%), followed by oval-oblong (19.4%). Conditions of remaining forest fragments are unfavorable with the high degree of fragmentation caused by local agricultural practices.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Sergio Losada-Prado | Fecha: 2016

Los páramos almacenan y capturan gas carbónico atmosférico y son clave en el equilibrio del ciclo hídrico y regulación del clima regional. Dada su relevancia, en el 2013 se evaluó la fauna epigea del páramo Estambul (Tolima, Colombia), entre 3100 m a 3600 m s.n.m. Se realizó un muestreo preliminar, siguiendo el gradiente altitudinal mencionado, para ubicar cinco estaciones de muestreo. Se procuró ubicar posteriormente cada estación de muestreo en áreas conservadas o poco perturbadas. En cada estación se estableció un transecto lineal de 100 m, se ubicaron puntos separados 20 m uno de otro, y se hicieron las colectas de hojarasca (sacos mini-Winkler), con trampas de caída y búsqueda manual. Se registraron 2617 organismos, 28 órdenes y 75 familias. Acari registró mayor abundancia (606 organismos), mientras que Julida y Psocoptera, presentaron cada uno un individuo. Los estimadores no paramétricos de riqueza de especies Jack 2 y Chao 2 indican que se registró entre el 81 % - 90 % de las especies esperadas, lo cual evidencia un buen muestreo de la artropofauna epigea del páramo y que la biota registrada varía en su composición, abundancia y diversidad, en el gradiente altitudinal.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Patricio Mena-Valenzuela | Fecha: 2016

The leucismo is an aberration in pigmentation, resulting from a genetic abnormality and occurs in all vertebrate groups in which the fish are included. In Ecuador, it has not reported such anomalies in fish. Is presented for the first time a case of partial leucismo in an individual of Andean Catfish (Astroblepidae), observed in a spring located near the Lake San Pablo Canton Otavalo, Imbabura Province, Ecuador.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Ángela María Mogollón-Ortiz | Fecha: 2017

The soil microbiota is a biological indicator. The impact of four different land use patterns: Secondary forest (T1), rice monoculture (T2), pineapple monoculture (T3) and agroforestry system of Theobroma cacao associated with Acacia mangium (T4) at different distances: 0-10 cm (D1), 10-20 cm (D2), 20-30 cm (D3), 30- 40 cm (D4) and 40-50 cm (D5) on counts of Colony Forming Units (CFUs) of fungi, bacteria, actinobacteria were tested in an Oxisol of Villavicencio, Orinoquia, East Colombia. An unrestricted random design was applied. More number of CFUs of soil bacteria, fungi and actinobacteria were recorded in secondary forest (T1) at all the distances from the root surface when compared to the other treatments. However, a similar trend was observed for counts of CFUs of soil fungi and bacteria in secondary forest (T1) at (D4) and (D5) distances from the root surface compared with agroforestry system (T4) at all distances from the root surface (P≤0.05). Meanwhile that there was similarity in number of CFUs of soil actinobacteria between secondary forest (T1) and agroforestry system (T4) at all the distances (P≥0.05). The least count of CFUs of soil microbiota was recorded in pineapple monoculture (T3) at all the distances from the root surface (P≤0.05).

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Carlos A. Lasso | Fecha: 2016

A new species, Aequidens superomaculatum, is described from the Casiquiare Canal drainage and the upper reaches of the Orinoco and Negro rivers (Venezuela). This new species shares with others of the genus a vermiculated color pattern on the cheek, snout and preopercle and a high vertebral count, but it differs from congeners in having a continuous lateral stripe, and in having the lateral dark pigment blotch positioned high on both sides of the body.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Diego Giraldo-Cañas | Fecha: 2017

As a result of recent studies on Neotropical grasses, a checklist of the South American species of Digitaria is provided. This checklist includes 65 species, of which 53 are native (34 are endemic) and 12 are introducednaturalized. Brazil has 48 species (12 endemic), followed by Venezuela (29/1), Paraguay (28/0), Colombia (27/2), Argentina (26/1), and Bolivia (24/1). On the other hand, D. velutina (Forssk.) P. Beauv., a native species from Africa, Arabia, and Yemen, is recorded for the first time in South America. This paper includes the morphological similarities and differences between D. velutina and D. abyssinica (Hochst. ex A. Rich.) Stapf. The names D. bonplandii Henrard and D. mattogrossensis (Pilg.) Henrard, are included in the synonymy of D. corynotricha (Hack.) Henrard.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: María del Carmen Zuñiga | Fecha: 2017

The Entomology Museum of the University of Valle (MUSENUV) holds a collection of adult (male and female) Anacroneuria (Plecoptera) specimens which currently represents 75,4% of the known species richness of Colombia (61). In order to expand the knowledge about biodiversity and distribution of this genus in Colombia and the Neotropics, we conducted a review of the specimens deposited in the MUSENUV, in Cali. The specimens correspond to different studies conducted between 1991 and 2011. Field collection of adult individuals (male and female) using two white/black light traps, operated between 18:00 and 21:00 hours accounted for 97% of the collection events. The remaining percentage was obtained by direct collection, using entomological nets either by sampling riparian vegetation or capturing insects at daylight flight. Specimens belong to13 departments, 53 municipalities and about 120 locations, primarily located in the upper and middle Cauca River drainage, from an altitude range between 10 and 3100 m a.s.l. The Andean region was the best represented followed by the Pacific, Caribbean and Amazon regions. There is a gap of information from the Orinoco region. The present data have a great value because provide adequate regional biodiversity assessment, which is crucial to establish environmental diagnostic and conservation strategies.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros