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The bullfrog, Lithobates catesbeianus, is one of the one hundred worst invasive species in the world. Its introduction into the Venezuelan Andes is worrying due to the large number of endemic species that could be affected by its presence. We examined the dispersal of Lithobates catesbeianus in western Venezuela to identify the areas where follow-up and control are a priority to avoid further invasion. Based on data on absence and presence of the bullfrog, we updated its distribution and compared it to records from 2005 (46.001 km2) and 2010 (53.502 km2). The area invaded by 2013 was 76.417 km2, 1.6 times the distribution in 2005, growing at a rate of 3,041 km2 per year. Factors such as inclination of the terrain, presence of forests and bodies of fast moving water could be acting as barriers to further dispersal. Taking into account that the distribution of this species in Venezuela by 2013 was limited to the basins of the rivers Capazón, Las González and Quebrada La Sucia in Mérida state; the regions at the greatest risk of being invaded due to natural dispersal are downriver from these bodies of water. However, the risk of invasion exists due to human introduction in nearby areas similar to those currently inhabitedby the bullfrog. Our recommendations are the conservation and reforestation of forests in the area, the creation of early warning protocols for the areas at greatest risk of invasion, and the continuation of measures prohibiting the transportation of bullfrogs outside of their current distribution.

Pseudogonatodes lunulatus (Roux, 1927) was described from a single specimen collected in the village El Mene, Acosta municipality, northeastern Falcón state, Venezuela. Although the species has been reported for other Venezuelan and Colombian localities, an extensive study on taxonomy and geographic distribution in the country had not been performed. In this sense, we examined and compared a larger sample of 20 specimens deposited in several national and foreign museums. Additionally, we substantially expand the known distribution of the species to the north of the Orinoco River.

Gastrotheca ovifera es una rana marsupial que habita en el dosel arbóreo de bosques nublados y ribereños del Tramo Occidental y Ramal Litoral de La Cordillera de la Costa venezolana (CCV) entre 820-2 000m de altitud. De acuerdo con la Lista Roja de la UCN se encuentra En Peligro (EN) y su evaluación fue realizada de acuerdo a apreciaciones anecdóticas, por lo que su situación de amenaza no ha sido comprobada por muestreos sistemáticos. Con el objetivo de estudiar el estado de las poblaciones de la especie en el Parque Nacional Henri Pittier (PNHP) en el Ramal Litoral de la CCV, realizamos una revisión histórica en museos nacionales y extranjeros y encontramos que la especie fue registrada en 1996 por última vez en el PNHP. Acumulamos 646 horas/persona de muestreo sistemático en localidades históricas y adicionales de la especie en el parque durante los años 2006 y 2007 y no obtuvimos registro de la especie. Adicionalmente, realizamos asociaciones entre datos promedios de precipitación anual y el registro histórico de la especie durante el periodo 1941-1997 (r s=- 0.054, p=0.820, n=19). Discutimos sobre su estado de conservación con base a la distribución, fluctuación y cambios poblacionales de la especieHistoric record of Gastrotheca ovifera (Anura: Hemiphractidae): decline evidence in Venezuelan coastal cloud forests. G. ovifera is a marsupial frog of the cloud and riparian forest from Western and Litoral sections of the Venezuelan Cordillera de la Costa (820-2 000m). This amphibian is considered as an endangered species by the IUCN Species Red List, due to its population decline in pristine and well preserved environments. This conservation status is based on anecdotic interpretations. We collected disperse data from museum records (national and international) and explored the possible association between collection records and precipitation data available for the Henri Pittier National Park (PNHP). Likewise, we carried out a systematic population monitoring of G. ovifera in historic and additional localities among the cloud forest of Rancho Grande, PNHP. We found 106 individuals in 11 zoological collections deposited during 1929-2007. After an effort of 646 hours/ person we did not detect G. ovifera individuals in the evaluated localities; as well as no statistical significant associations between the annual precipitation average and the historic records of the species during 1941-1997 period (r s=-0.054, p=0.820, n=19). We discussed the distribution, fluctuation and population changes of this species, analyzing it conservation status. Rev. Biol. Trop. 59 (1): 329-345. Epub 2011 March 01.

G. ovifera is a marsupial frog of the cloud and riparian forest from Western and Litoral sections of the Venezuelan Cordillera de la Costa (820-2 000m). This amphibian is considered as an endangered species by the IUCN Species Red List, due to its population decline in pristine and well preserved environments. This conservation status is based on anecdotic interpretations. We collected disperse data from museum records (national and international) and explored the possible association between collection records and precipitation data available for the Henri Pittier National Park (PNHP). Likewise, we carried out a systematic population monitoring of G. ovifera in historic and additional localities among the cloud forest of Rancho Grande, PNHP. We found 106 individuals in 11 zoological collections deposited during 1929-2007. After an effort of 646 hours/person we did not detect G. ovifera individuals in the evaluated localities; as well as no statistical significant associations between the annual precipitation average and the historic records of the species during 1941-1997 period (r = -0.054, p = 0.820, n = 19). We discussed the distribution, fluctuation and population changes of this species, analyzing it conservation status.