Photographic evidence of undescribed species of velvet worms (Onychophora: Peripatidae) from Costa Rica. Onychophorans are hard to find and identify to species under field conditions. Currently, there are seven species described from Costa Rica, and an appropriate taxonomic revision is necessary. However, technology allows the documentation of rare and even undescribed species. Here we compile donated photographs and online images to identify 18 new Costa Rican species (based on taxonomic characteristics or geographical distribution). In addition we present relevant scientific information for each. Although it is not possible to make a formal description of species from photographs, this compilation shows where they can be searched for future research. Our goal is to preserve this information and to raise awareness among biology students and nature photographers about the importance of finding an onychophoran. These findings frequently result in new species discoveries.Key words: Citizen Science, Neotropic, Undescribed species, Onychophorans, Peripatus. RESUMEN:Los onicóforos son animales difíciles de encontrar e identificar a nivel de especie en condiciones de campo. En la actualidad hay siete especies descritas en Costa Rica, y existe la necesidad de una adecuada revisión taxonómica. Sin embargo la tecnología permite la documentación de especies raras e incluso no descritas. Compilamos fotografías donadas e imágenes que se encuentran en línea y logramos identificar 18 especies nuevas para Costa Rica (basados en las características taxonómicas y distribución geográfica). Adicionalmente presentamos información de relevancia científica sobre las mismas. A pesar de que no se puede hacer una descripción formal de la especie solo con las fotografías, la información que nos brinda permite conocer nuevas localidades para investigaciones futuras. Nuestro objetivo es preservar esta información y sensibilizar a los estudiantes de biología y fotógrafos de la naturaleza, sobre la trascendencia de cada hallazgo de un onicóforo. Estos hallazgos con frecuencia dan lugar a descubrimientos de nuevas especies.

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Biological communities are experiencing rapid shifts of composition in Neotropical ecosystems due to several factors causing population declines. However, emerging evidence has provided insights on the adaptive potential of multiple species to respond to illnesses and environmental pressures. In Costa Rica, the decline of amphibian populations is a remarkable example of these changes. Here we provide evidence of variation in the amphibian richness of a premontane forest of San Ramón (Costa Rica) across a ~30 year period. We also quantified changes in the composition and abundance of the leaf-litter frog community occurring in the same premontane forest, by comparing diversity data with a difference of ~18 years. We evaluated the similarity of species richness from 1980s to 2010s based on several sources, and the dissimilarity of species diversity in the site comparing 28 standardized surveys from 1994-1995 and 2011-2012. We compared the relative abundance of some frogs that inhabit the leaf-litter layer between these same periods. Our results show that there is more similarity in amphibian richness between 1980s and 2010s (~ 52 %) than between 1980s and 1990s (~ 40 %). The richness of leaf-litter anurans was ~ 65 % similar between 1990s and 2010s. The diversity of leaf-litter anuran was clearly different between 1994-1995 and 2011-2012, and it was clustered among those periods. We determined that the amphibian community in this premontane forest drastically changed: many species have disappeared, or gradually declined through the decades (e.g. Pristimantis ridens, P. cruentus, Craugastor bransfordii) as in other well studied localities of Costa Rica, while some few species flourished after being almost absent from the site in the 1990s (e.g. Craugastor crassidigitus, Lithobates warszewistchii). Currently dominant species such as C. crassidigitus would be using developed resistance against Bd-fungus as an advantage (apparent competition) in the premontane forest where the disease is more virulent than in lowlands. Our analysis supports the hypothesis of individualized responses of anuran populations under distinct site and elevations. We suggest to continue monitoring the amphibian communities of premontane tropical forests to understand how this ecosystem gradually resist and adapts to this catastrophic time of biodiversity loss.

We provide a checklist of the amphibians and reptiles of Río Macho Biological Station (RMBS), Costa Rica. During a period of a year (2012–2013) we conducted visual and acoustic surveys in a natural mature forest plot (>50 years old) (MF), secondary forest plot (~17 years old) (SF), in open areas and riparian forest at RMBS. We found a total of 11 species of amphibians and 15 species of reptiles belonging to 11 taxonomic families. We also compared the diversity of the MF against the SF. The MF contained 10 species (five amphibians and five reptiles) and the SF seven (three amphibians and four reptiles), with similar dominance between sites. Unfortunately, some forest and riparian species have vanished at this elevation after an enigmatic decline; according to historical literature pristine areas should contain higher species richness. Perhaps, the secondary forest will provide an available habitat for an important percentage of the remaining forest species.

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Treefrogs represent 22% of amphibian species in Costa Rica, but gaps in the knowledge about this group of amphibians can impede conservation efforts. In this study, we first updated the status of Costa Rican treefrogs and found that a total of 38% of treefrog species are threatened according to the most recent IUCN assessment in 2019. Additionally, 21% of Costa Rican treefrog species have a high vulnerability to extinction according to environmental vulnerability scores. Then, we predicted the historical climatic suitability of eight target species that we expected to have exhibited changes in their ranges in the last 20 years. We assessed the location of new occurrence records since 2000 to identify recovery, range expansion, or previously underestimated ranges due to methodological limitations. We also estimated the area of each species’ suitable habitat with two metrics: extent of suitable habitat (ESH) and area of minimum convex polygon (AMCP). Six declined species exhibited recovery (i.e., new occurrences across historical range after 2000), with the widest recovery found in Agalychnis annae. We also found that Isthmohyla pseudopuma appears to have spread after the decline of sympatric species and that the range of I. sukia was originally underestimated due to inadequate detection. We found that the ESH was 32–49% smaller than the AMCP for species that are slowly recovering; however, the ESH is similar or greater than the AMCP for species that are recovering in most of their ranges, as well as rare species with widespread ranges. Results of this work can be used to evaluate the risk of environmental threats and prioritize regions for conservation purposes.

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El 05 de junio de 2016 (08h00), observamos un evento de depredación de este roedor sobre un ave canora en el Jardín Botánico Wilson de la Estación Biológica Las Cruces en San Vito, Provincia de Puntarenas, Costa Rica (8.785, -82.95916;1200 msnm). Inicialmente un macho de D. punctata se alimentaba de frutos y raíces, pero repentinamente tras desplazarse sigilosamente se abalanzó sobre un pichón de yigüirro o mirlo pardo (Turdus grayi). Tras capturarlo con sus patas delanteras, el roedor lo mató con sus dientes incisivos, y posteriormente se desplazó algunos metros hasta empezar a consumirlo (Figura 1). La posiciónque usó la Guatusa para depredar y posteriormente consumir el ave es la misma que usa para alimentarse de semillas; sentándose en sus patas traseras y manipulando el alimento con las delanteras (Mora & Moreira 1984). Tras unos 15 minutos el roedor había consumido parte del ave incluyendo músculos, vísceras e incluso su cabeza. Finalmente, el roedor huyó sin dejar restos de la presa en el sitio al llevarse parte de la carcasa en el hocico