Resumen En este trabajo, se amplía la distribución del género Amanahyphes y de la especie A. saguassu Salles & Molineri, mediante el primer registro para Colombia y Perú. Los departamentos donde se encontraron estos especímenes pertenecen a la región amazónica de ambos países, son: Amazonas, Guaviare y Vaupés (Colombia); Madre de Dios (Perú). La especie identificada en este trabajo, había sido registrada previamente solamente para Brasil y Venezuela.

Abstract In this work, the distribution of Amanahyphes genus and A. saguassu Salles & Molineri species is expanded through the first records from Colombia and Perú. The departments where these specimens were found belong to the Amazon region of both countries, they are: Amazonas, Guaviare and Vaupés (Colombia); Madre de Dios (Perú). The species identified in this work was previously recorded only in Brazil and Venezuela.

Resumen El conocimiento acerca de la distribución de Odonata en Colombia ha aumentado, contribuyendo así a disminuir los vacíos de información en la distribución de algunos taxones. En este estudio, se reporta el género Peruviogomphus para Colombia con base en dos ninfas colectadas en el departamento del Amazonas y depositadas en la Colección de Macroinvertebrados Acuáticos de la Amazonia Colombiana (COMAC), del Instituto SINCHI. Este hallazgo actualiza los registros de Peruviogomphus en América del Sur.

Abstract The knowledge about the distribution of Odonata in Colombia has increased thus contributing to reduce the information gaps in the distribution of some taxa. In this study, the Peruviogomphus genus is reported for Colombia, based on two nymphs collected in the Department of Amazonas and deposited in the Colección de Macroinvertebrados Acuáticos de la Amazonia Colombiana (COMAC), of the SINCHI Institute. This finding updates the records of the Peruviogomphus genus in South America.

Chlorococcales of the Colombian Amazon. II. In this paper 41 taxa belonging to the families Coelastraceae, Chlorococcaceae, Radiococcaceae, Palmellaceae, Oocystaceae, Characiaceae, Treubariaceae, Botryococcaceae, Micractiniaceae and Hydrodictyaceae of the order Chlorococcales were recorded. The material studied was collected in rivers and lakes from Colombian Amazon basin. Among the total taxa recorded, 20 are new for Colombia and 10 are new for the Colombian region of the basin. The family best represented in terms of species richness was Oocystaceae, with 10 taxa, and the largest number of taxa was found in lakes Yahuarcaca (Amazon River).

En el presente trabajo se registran 41 taxa, pertenecientes a las familias Coelastraceae, Chlorococcaceae, Radiococcaceae, Palmellaceae, Oocystaceae, Characiaceae, Treubariaceae, Botryococcaceae, Micractiniaceae e Hydrodictyaceae (orden Chlrorococcales) hallados en ríos y lagos de la cuenca de Amazonia Colombiana. Del total encontrado, 20 son nuevas citas para el país y 10 para la cuenca en Colombia. La familia mejor representada, en cuanto a riqueza específica, fue Oocystaceae con 10 taxa y en los lagos Yahuarcaca (Río Amazonas) se ha registrado el mayor número de taxa del orden.

La flora diatomológica de la Amazonia Colombiana y Peruana está mucho menos estudiada que la flora del sector brasilero. Se presentan los resultados de los géneros Encyonema, Encyonopsis y Gomphonema. Muestras de plancton y perifiton fueron colectadas en ambientes lóticos y lénticos de la región amazónica-andina, en los ríos Amazonas, Japurá y Porvenir durante 1993, 1994, 2001 y 2003. En cada estación de muestreo se realizaron mediciones de pH, temperatura, transparencia del agua y conductividad. Las muestras fueron analizadas con microscopio óptico con contraste de fases y microscopio electrónico de barrido. Diez taxones son nuevos registros para el área; Encyonema en la Amazonia peruano-colombiana y Encyonopsis en el sector colombiano. Encyonema neogracile var. tenuipunctatum, E. vulgare, Encyonopsis frequentis, Gomphonema augur var. sphaerophorum y G. contraturris se reportan por primera vez en Colombia; Encyonema venezolanum y Gomphonema neoapiculatum en Colombia y Perú y la última también en la Amazonia. E. angustecapitatum fue previamente registrada en una laguna de altura en Colombia localizada a 3.000 msnm. Se describe una nueva especie, Encyonema amazonianum, colectada en el Río Porvenir, Amazonas, Colombia.

Diatoms from the Colombian and Peruvian Amazon: the Genera Encyonema, Encyonopsis and Gomphonema (Cymbellales, Bacillariophyceae). The diatom flora of the Colombian and Peruvian Amazon is far less studied than the flora of the Brazilian sector of the basin. Here we present results related to the genera Encyonema, Encyonopsis and Gomphonema. Plankton and periphyton samples were collected in lotic and lentic waterbodies from the Amazonian-Andean region, the Amazon River, Japurá River and Porvenir River basins during 1993, 1994, 2001 and 2003. At each sampling station pH, temperature, water transparency and conductivity were registered. Samples were analyzed with phase contrast microscope (LM) and scanning electron microscope (SEM). Ten taxa are new records for the area; Encyonema for the Peruvian and Colombian Amazon and Encyonopsis for the Colombian Sector. Encyonema neogracile var. tenuipunctatum, E. vulgare, Encyonopsis frequentis, Gomphonema augur var. sphaerophorum and G. contraturris are recorded for the first time in Colombia; Encyonema venezolanum and G. neoapiculatum in Colombia and Peru and the latter also for Amazonia. E. angustecapitatum was mentioned in Colombia before at a pond located at 3000m asl. We describe a new species from Porvenir River, Amazonas, Colombia: Encyonema amazonianum. Rev. Biol. Trop. 58 (1): 45-62. Epub 2010 March 01.

O trabalho realizou-se nas três bacias mais importantes da Amazônia Colombiana (Alto Solimões, Içá e Japurá). Os igarapés e lagos estudados apresentam alta riqueza de diatomáceas, principalmente do gênero Eunotia. Foram descritas 10 espécies e, pela primeira vez, a morfologia das valvas de E. anamargaritae, E. pseudoindica, E. triodon e E. zydodon var. compacta, foram descritas ao microscópio eletrônico. Dentre as espécies de Eunotia, encontradas no presente estudo, seis são primeiras citações para a Colômbia e cinco para a região amazônica.

This research was carried out in three of the most important basins of the Colombian Amazon (Upper Solimões, Iça and Japurá Rivers). The creeks and lakes that were studied contain abundant diatom species, particularly those of the genus Eunotia. Ten species are described; five of them are registered for the first time in the Amazon basin, and six in all of Colombia. All taxa were photographed with scanning electron microscopy. Fine valve morphology of E. anamargariate, E. pseudoindica, E. triodon, and E. zydodon var. compacta is described for the first time.