ABSTRACT
The spatial arrangement of organisms is significantly influenced by the structure of vegetation. Bromeliads, characterized by a remarkable architectural design featuring rosette-like leaf arrangements for rainwater storage, act as habitats for various organisms. These organisms use bromeliads for shelter, foraging, reproduction and the supply of nutrients and moisture. This study investigated how specific aspects of bromeliad structure, such as the number, width and length of leaves, impact the behaviour and distribution patterns of the bromelicolous scorpion Tityus neglectus. In the examination of 110 sampled bromeliads, 33 scorpions were recorded, resulting in an occupancy rate of 30%. The likelihood of scorpion occurrence was associated with the plant's structure. The length and coefficient of variation in the width of leaves appeared as the main predictors, positively influencing scorpion presence while the number of leaves exhibited a negative relation with scorpion occurrence. The distribution of scorpions was uniform across the spatial design of bromeliads. Furthermore, T. neglectus demonstrated the ability to utilize water accumulated in the bromeliad to evade potential predators, submerging itself for, on mean, almost 8 min. We concluded that bromeliad structure is essential in shaping the distribution patterns and anti-predatory behaviour of T. neglectus.
ABSTRACT
We describe a new species of Rain Frog from Brazils Atlantic Forest, which harbors high richness, endemism and threatened species of anurans. Ischnocnema crassa sp. nov. is a leaf litter breeder from the montane rainforest of Santa Teresa, state of Esprito Santo, southeastern Brazil. Remarkably, the new species is so far unique amongst Ischnocnema for having moderate hand webbing between fingers. Ischnocnema crassa sp. nov. is the third species belonging to I. parva series and we present a new phylogeny based on molecular data and propose a new diagnosis for the series. We provide field and laboratory observations regarding amplexus, antipredator mechanisms, microhabitat preferences and conservation remarks. Although Santa Teresa is one of the most sampled areas in Brazil, new species are often discovered. Santa Teresa is a priority for amphibian conservation because it harbors 109 species of anurans (9% of Brazils species).
Subject(s)
Anura , Forests , Animals , Anura/genetics , Brazil , Phylogeny , RainforestABSTRACT
Many animals breed exclusively in plants that accumulate rainwater (phytotelma; e.g., bromeliad, bamboo, fruit husk, and tree hole), to which they are either physiologically or behaviorally specialized for this microhabitat. Of the numerous life-history modes observed in frogs, few are as striking or potentially consequential as the transition from pond- or stream-breeding to the deposition of eggs or larvae in phytotelmata. Such specialization can increase offspring survivorship due to reduced competition and predation, representing potential ecological opportunity for adaptive radiation, yet few lineages of phytotelma-breeding frogs appear to have diversified extensively after such a transition, at least in the New World. We use a phylogeny of Neotropical frogs and data on breeding microhabitat to understand the evolutionary transitions involved with specialized phytotelma-breeding. First, we find that phytotelma-breeding is present in at least 168 species in 10 families of frogs. Across the phylogeny, we estimate 14 origins of phytotelma-breeding and 115 reversals, showing that phytotelma-breeding is a highly labile character. Second, phytotelma-breeding lineages overall have higher net diversification than nonphytotelma-breeding ones. This specialization represents an ecological opportunity resulting in increased diversification in most families with phytotelma-breeding lineages, whereas phytotelma-breeding toads have restricted diversification histories.
Subject(s)
Anura/genetics , Biological Evolution , Ecosystem , Reproduction , Americas , Animals , Models, GeneticABSTRACT
Abstract: Anurans are predator and prey, playing an important role in ecosystem functioning. The diet composition is closely related to feeding strategy, and the information about prey items is useful to understand intra and interspecific interactions in trophic webs. Here we determined diet composition, feeding strategy, and relation between prey ingestion and body measures of Crossodactylus timbuhy, a recently described anuran species. We found 466 prey items from 20 prey categories in the stomach of 66 specimens (15 males and 51 females) of C. timbuhy. The diet consists mostly of Formicidae and Coleoptera, the items with the highest number, frequency of occurrence and prey importance. The diet composition was relatively similar to other species of Crossodactylus. Prey volume was positively related to frog size and weight, suggesting frogs may feed upon any prey they can swallow. Diet showed some variation between sexes. Despite females were larger and heavier than males, females had higher consumption of smaller prey, and ingested a larger number of prey categories. We suggest C. timbuhy has an invertebrate-opportunistic feeding habit. It is likely C. timbuhy uses a combination of 'sit-and-wait' and 'active search' strategies due to high consumption of both highly mobile and sedentary prey.
Resumo: Os anuros são predadores e presas, desempenhando um importante papel no funcionamento dos ecossistemas. A composição da dieta está intimamente relacionada à estratégia de forrageamento das espécies e as informações sobre os itens consumidos são úteis para compreensão das interações intra e interespecíficas nas redes tróficas. O presente estudo objetivou determinar a composição da dieta, a estratégia de forrageamento e a relação entre a ingestão de presas e as medidas corporais de Crossodactylus timbuhy, uma espécie de anuro descrita recentemente. Foi analisado o conteúdo estomacal de 66 espécimes (15 machos e 51 fêmeas) de C. timbuhy e registrados 466 itens alimentares, distribuídos em 20 categorias de presas. A dieta consistiu principalmente de Formicidae e Coleoptera, as quais apresentaram maior número de itens consumidos, maior frequência de ocorrência e maior importância entre as presas registradas. A composição da dieta foi relativamente semelhante à de outras espécies do gênero Crossodactylus. O volume das presas foi positivamente relacionado com o tamanho e o peso dos espécimes, sugerindo que os indivíduos podem se alimentar de qualquer presa que eles possam engolir. A dieta apresentou variação entre os sexos. Apesar das fêmeas serem maiores e mais pesadas do que os machos, elas consumiram mais presas menores e ingeriram mais categorias de presas. Sugere-se que C. timbuhy tenha hábito alimentar invertebrado-oportunista. É provável que C. timbuhy apresente uma combinação de estratégias "senta-e-espera" e "forrageador ativo" devido ao alto consumo de presas altamente móveis e de presas sedentárias.
ABSTRACT
The genus Zachaenus Cope is the least specious within Cycloramphidae, including two species: Z. carvalhoi Izecksohn, and Z. parvulus (Girard). Both are leaf litter species distributed across Atlantic forest remnants in Southeastern Brazil. Zachaenus carvalhoi occurs westerly in the states of Espírito Santo and Minas Gerais, and Z. parvulus easterly in the states of São Paulo, Rio de Janeiro, and Espírito Santo (Verdade et al. 2009; Motta et al. 2010; Salles Maciel 2010; Oliveira et al. 2012; Guedes et al. 2019; Frost 2019). Both species build terrestrial nests, and larval development is endotrophic nidicolous (reproductive mode 21 after Haddad Prado 2005; Lutz 1944; Thibaudeau Altig 1999; Zocca et al. 2014). In this work, we describe the tadpoles of Z. carvalhoi, and discuss morphological aspects regarding other endotrophic tadpoles.
Subject(s)
Ranidae , Animals , Brazil , Forests , LarvaABSTRACT
A checklist of the amphibians of Santa Teresa municipality, in southeastern Brazil is presented based on fieldwork, examination of specimens in collections, and a literature review. This new amphibian list of Santa Teresa includes 108 species, of which 106 (~98%) belong to Anura and two (~2%) to Gymnophiona. Hylidae was the most represented family with 47 species (43%). Compared to the previous amphibian lists for Santa Teresa, 14 species were added, 17 previously reported species were removed, and 13 species were re-identified based on recent taxonomic rearrangements. Of the 14 species added, 11 (79%) were first recorded during our fieldwork and specimen examination. It is also the first list of caecilians for Santa Teresa. This list suggests that Santa Teresa has 0.16 species per km2 (i.e., 108 species/683 km2), one of the highest densities of amphibian species in the world at a regional scale. This richness represents 78% of the 136 anurans from Espírito Santo state and 10% of the 1,080 amphibians from Brazil. We highlight the need for long-term monitoring to understand population trends and develop effective conservation plans to safeguard this remarkable amphibian richness.
ABSTRACT
The genus Adelophryne is composed of diminutive frogs occurring in northern Amazonia and the Atlantic Forest. Herein we describe a new species of Adelophryne found in the leaf litter of primary and secondary forests in the mountainous region of Espírito Santo state, southeastern Brazil. The new species is characterized by its small body size, two phalanges in the finger IV, and a glandular ridge line that runs from the posterior part of eye to the insertion of the forelimb. This species is sensitive to edge effect and conversion of native forest into coffee and Eucalyptus plantations and may be listed as Endangered (EN) under B1ab(iii) criteria of the IUCN Red List.
