Catalogue of type specimens deposited in the Herpetology Collection of the Natural History Museum Gustavo Orcés V. at Escuela Politécnica Nacional (Ecuador).

Background: The Herpetology Collection of the Natural History Museum Gustavo Orcés V. at Escuela Politécnica Nacional (MEPN-H) in Quito maintains more than sixteen thousand curated specimens and it comprises Ecuador ´s second largest collection of herps. New information: The Collection contains 193 type specimens: 14 holotypes, 34 paratopotypes and 145 paratypes, which correspond to 10 families, 17 genera and 32 species. The collection of type specimens is particularly important in the genera Atelopus and Pristimantis in amphibians and the genera Atractus and Enyaloides in reptiles. An assessment of the geographic distribution showed that collection sites of type specimens are clustered towards the south of Ecuador in the provinces of Zamora Chinchipe, Morona Santiago and Pastaza in the Amazon Region; and in the provinces of Carchi and Azuay in the Andes. The collection of type specimens dates from 1955 to 2013, comprising an invaluable source of historical biodiversity data.

Post-epizootic microbiome associations across communities of neotropical amphibians.

Microbiome-pathogen interactions are increasingly recognized as an important element of host immunity. While these host-level interactions will have consequences for community disease dynamics, the factors which influence host microbiomes at larger scales are poorly understood. We here describe landscape-scale pathogen-microbiome associations within the context of post-epizootic amphibian chytridiomycosis, a disease caused by the panzootic chytrid fungus Batrachochytrium dendrobatidis. We undertook a survey of Neotropical amphibians across altitudinal gradients in Ecuador ~30 years following the observed amphibian declines and collected skin swab-samples which were metabarcoded using both fungal (ITS-2) and bacterial (r16S) amplicons. The data revealed marked variation in patterns of both B. dendrobatidis infection and microbiome structure that are associated with host life history. Stream breeding amphibians were most likely to be infected with B. dendrobatidis. This increased probability of infection was further associated with increased abundance and diversity of non-Batrachochytrium chytrid fungi in the skin and environmental microbiome. We also show that increased alpha diversity and the relative abundance of fungi are lower in the skin microbiome of adult stream amphibians compared to adult pond-breeding amphibians, an association not seen for bacteria. Finally, stream tadpoles exhibit lower proportions of predicted protective microbial taxa than pond tadpoles, suggesting reduced biotic resistance. Our analyses show that host breeding ecology strongly shapes pathogen-microbiome associations at a landscape scale, a trait that may influence resilience in the face of emerging infectious diseases.

A new treefrog from Cordillera del Cóndor with comments on the biogeographic affinity between Cordillera del Cóndor and the Guianan Tepuis (Anura, Hylidae, Hyloscirtus).

The Hyloscirtuslarinopygion group is a clade of 16 species of large hylids that inhabit cascading Andean streams. They have brown coloration that, in most species, contrasts with bright marks. Herein morphological and genetic evidence is used to describe a new species of the group from Cordillera del Cóndor, a sub-Andean mountain chain that has phytogeographic affinities with the Guianan Tepuis. The new species is characterized by dark-brown coloration with contrasting bright orange flecks and by the presence of an enlarged and curved prepollex protruding as a spine. The new species is closely related to H.tapichalaca and an undescribed species from the southern Andes of Ecuador. The genetic distance between H.hillisi sp. n. and its closest relative, H.tapichalaca, is 2.9% (gene 16S mtDNA). Our phylogeny and a review of recently published phylogenies show that amphibians from Cordillera del Cóndor have close relationships with either Andean or Amazonian species. Amphibians do not show the Condor-Guianan Tepuis biogeographic link that has been documented in plants.

Embryogenesis and laboratory maintenance of the foam-nesting túngara frogs, genus Engystomops (= Physalaemus).

The vast majority of embryological research on amphibians focuses on just a single genus of frogs, Xenopus. To attain a more comprehensive understanding of amphibian development, experimentation on non-model frogs will be essential. Here, we report on the early development, rearing, and embryological analysis of túngara frogs (genus Engystomops, also called Physalaemus). The frogs Engystomops pustulosus, Engystomops coloradorum, and Engystomops randi construct floating foam-nests with small eggs. We define a table of 23 stages for the developmental period in the foam-nest. Embryos were immunostained against Lim1, neural, and somite-specific proteins and the expression pattern of RetinoBlastoma Binding Protein 6 (RBBP6) was analyzed by in situ hybridization. Due to their brief life-cycle, frogs belonging to the genus Engystomops are attractive for comparative and genetic studies of development. Developmental Dynamics 238:1444-1454, 2009. (c) 2009 Wiley-Liss, Inc.