This study modeled the distribution of the M. divaricatus complex in Nuclear Central America (NCA) by testing multiple modeling techniques and identifying crucial bioclimatic predictors. We used 178 occurrence records and seven variables selected for ecological relevance and low collinearity. Validating the eight techniques using AUC, TSS, Cohen's Kappa, sensitivity, Models, and Maximum Entropy Modeling performed best, with Random Forest showing the highest predictive accuracy. Main predictors were temperature seasonality, precipitation of the driest month, and precipitation seasonality. Projections indicated high suitability along the Pacific and Caribbean slopes and in parts of the Mosquitia, and low suitability in the Chort & iacute;s Block highlands. Lowland and premontane moist forests were identified as critical habitats. The Chort & iacute;s Block highlands represent a transitional zone for the three subspecies. These results, obtained via a multi-model approach to reduce uncertainty, provide relevant insights for taxonomy and conservation planning of the M. divaricatus complex and the genus Micrurus in NCA.
The Liolaemus walkeri clade comprises small, slender lizards, most species of which exhibit ventral melanism and a fragmented dark vertebral line. These lizards inhabit high Andean zones of Peru, although two field guide include photographs of L. tacnae from northern Chile, without voucher specimens or published scientific studies to support this taxonomic assignment. We recently examined specimens labeled L. cf. tacnae from Quebrada Blanca, Tarapac & aacute; Region, Chile, and performed morphological analyses, providing the first taxonomic assessment of a population of the L. walkeri clade outside Peru. Males of this population exhibit melanism on the throat and belly, and both sexes lack precloacal pores, among other diagnostic traits. We propose that this population represents a new species and highlight morphological characters of the L. walkeri clade that do not match those of the subgenus Liolaemus (sensu stricto). The L. walkeri clade lacks two of the three external characters used to diagnose the subgenus and does not exhibit some of the defining characters of the L. alticolor-bibronii group, where this clade is currently been placed by some studies. This observations suggest the need to evaluate the existence of a third subgenus of Liolaemus in future research.
We provide an update on the distribution of Buenaventuras glassfrog (Nymphargus buenaventura), adding a new locality in Peru. We extend the known geographic range of the species 180 km southward. We report for the first time its advertisement call, which consists of a high-pitched note. Morphological and molecular analyses confirmed the identity of the specimens, with 16S rRNA sequences exhibiting minimal genetic divergence (1.08%) from those of Ecuadorian populations. Additionally, we observed egg clutches exceeding previously reported clutch sizes. Given the extended range and lack of population data, we recommend placing N. buenaventura in the Data Deficient category of the IUCN Red List until further studies are conducted.
Population observations and microhabitat use of Isthmohyla tica (Anura: Hylidae) in San Ram & oacute;n, Costa Rica. Isthmohyla tica, the Tica Frog, is a critically endangered species endemic to Costa Rica and supposedly Panama that has only been seen in a few sites in recent decades. To aid in its conservation, we assessed the population status and microhabitat preferences of this frog in a section of the Danta stream at Rancho Alegre farm, San Ram & oacute;n, Costa Rica. We conducted 18 nocturnal surveys and collected data on perch types, vegetation associations, stream characteristics, and environmental variables for each sighting of the Tica Frog. To identify potential microhabitat preferences, we compared these features between sites with or without frogs as well as between sites with juvenile or adult individuals. We recorded 13 individuals, comprising three juveniles and 10 adults. Nine adults were male and one female, with the disparity likely due to the conspicuous vocalizations of males. Juvenile and adult frogs occupied areas with similar stream widths (t = 0.91; p = 0.38). However, juveniles were found closer to the water (t = 5.14, p = 0.01) and adjacent to shallower areas of the stream compared to adults (t = 2.50, p = 0.03). Frogs predominantly perched on Piper sp. (30.7%) and on the upper surface of leaves (69.2%). The height at which the Tica Frog was recorded (0.1 to 2.2 m) was similar for both age groups (t = 0.86, p = 0.44). We did not find significant differences in canopy cover (average = 74.6%), diameter at breast height (<= 3.14 cm), vegetation density (5.0 plants/m2), or plant richness (1-4 species) between juveniles and adults. Similarly, we did not observe differences in environmental variables between these groups. Furthermore, vegetation characteristics and environmental variables did not differ between sites with the Tica Frog and nearby sites without them. Our findings suggest that the measured variables do not significantly influence the microhabitat selection of the Tica Frog. This novel information on the population status and microhabitat use of I. tica is needed for the development of management strategies for the conservation of this critically endangered species.
Harlequin toads, genus Atelopus, are a species-rich group of Neotropical anurans. Unparalleled declines and extinctions have hampered a thorough understanding of Atelopus systematics with numerous species only known from few specimens and a single or few localities. Major knowledge gaps particularly remain in the Cordillera Central and Cordillera Oriental of the Colombian Andes. In the central Andes, the names Atelopus angelito, A. ebenoides, and A. eusebianus have caused taxonomic confusion because populations can show vast plasticity, and populations assigned to these names were thought to occur in sympatry and parapatry. The virtual disappearance of all populations has prevented an integrative taxonomic assessment and rendered molecular approaches highly challenging. Based on adult and larval morphology, we propose that these populations correspond to a single polymorphic taxon and establish A. ebenoides as the senior synonym. In contrast, a form from the northern Cordillera Oriental has been considered a subspecies of the latter, A. ebenoides marinkellei. These geographically highly distant populations differ in morphology, particularly in tadpole characters and do not appear to represent conspecifics. We therefore elevate the form marinkellei to species rank and provide detailed morphological redescriptions and tadpole accounts for both A. ebenoides and A. marinkellei.
For amphibians, gaps in knowledge about natural history and geographic distribution are among the major causes that blur our understanding of their diversity. These key pieces of information contribute to our understanding off taxonomy, systematics, ecology, and conservation. Herein, we provide new information on the geographic distribution and describe for the first time the advertisement call of Dendropsophus frosti from western Amazonia. The call consists of two types of short notes, a trilled multipulsed note with a duration ranging from 158 to 297 ms (note type A), and a high-pitched pulsatile note with a duration of about 9 ms (note type B). The dominant frequency of note type A is about 4260 Hz, while that of note type B is around 4330 Hz. The notes are emitted in two call arrangements, a complex call formed by one note type A followed by one or two type B notes or a composite call formed by two to seven type B notes. Overall, the call structure of D. frosti, with those two types of notes emitted in complex or composite calls, is shared with closely related species from the D. parviceps group, showing a phylogenetic signal. Our results suggest that acoustic characters may represent phylogenetic informative traits for the Dendropsophus parviceps group, supporting the current taxonomy. Additionally, our findings extended the known geographic distribution by approximately 700 km eastward. Our results highlight once again the necessity of biological surveys in remote areas of Amazonia, where many knowledge gaps persist.
Anatomical and osteological analyses in several species of ophidians belonging to the clade Caenophidia have led to the identification of differentstructures present in the cephalic shields of these reptiles. These structures are observed expressed mainly in the parietal shields, manifesting themselves in different forms. “Major parietal pits,” generally symmetrical, occur in the center of the parietal shields, more or less medially distanced to each other. These may appear circular, linear, separated, conjunct, or in contact with the lateral margin of the parietal shield by a slit. Together with the pits, a new distinct trait has been observed in the parietal shields of different species of colubroids, here named “parietal fossae.” Parietal pits and fossae are situated in correspondence with the paired foramina on the parietal bone’s dorsal plane, which in turn correspond ventrally with the epiphysis, and the contact between the cephalic hemispheres and the optic lobes. Other fossae may be present in certain species, occurring more posteriorly in the parietal shields, or in the supraocular shields, in correspondence with neurovascular foramina and fossae present in the underlying cranial bones. A second category of pits has also been found, here named “minor pits,” which appear randomly within the cephalic shields, and are also linked to neurovascular foramina present in the corresponding cranial bones. A third type of pit, distinct from the others, is the “medial posterior pit”, which has been found in aquatic snakes. This pit occurs in the posterior half of the medial contact of the parietal shields, and corresponds to a large central foramen in the posterior apex of the parietal bone’s plane, ventrally opening within a canal between the two fossae covering the optic lobes. All of these traits have been observed in a large number of snakes belonging to the families Colubridae, Natricidae, Psammophiidae, Atractaspididae, Pareidae, Xenodermidae, Micrelapidae and Elapidae. These do not occur in all individuals within the examined taxa, but rather affect part of the specimens of a given species. Fossae and pits appear to be sporadic surface structures that correspond to neurovascular foramina present in the underlaying cranial bones.
Uma nova espécie de Gegeneophis é descrita a partir da base dos planaltos lateríticos de Satara, Maharashtra, Índia. A nova espécie é descrita com base em várias linhas de evidência, incluindo características morfológicas, medições métricas e merísticas, análise filogenética, distâncias genéticas, análise ASAP e isolamento geográfico. As análises filogenéticas e ASAP sugerem a presença de seis linhagens adicionais que representam potenciais novas espécies do norte e centro dos Ghats Ocidentais. São discutidas as afinidades da distribuição espacial e temporal de Gegeneophis no norte e no centro dos Ghats Ocidentais.
Knowledge of the movements of amphibians can be useful in developing conservation strategies. We studied the movement of Ambystoma altamirani, a Mexican endemic salamander, in a montane stream near Mexico City, Mexico. We obtained movement estimates from 35 recaptured male, female, and juvenile salamanders. The majority of individuals moved during the study. Mean movements were > 250 m, with several individuals having movements > 500 m. Movements in A. altamirani did not have an upstream or downstream bias. Movement patterns (i.e., direction, mean distance, mean net displacement) did not differ among males, females, and juveniles. However, there was a tendency for the direction of net displacement to differ among males, females, and juveniles. Individuals that moved did not differ in snout–vent length (SVL) growth rate, initial SVL, or initial body mass (BM) from those that did not move; however, they showed greater BM change than those that did not move. We found that A. altamirani moved more than we had predicted. Our results suggest that maintaining aquatic and terrestrial conditions in the Arroyo los Axolotes to allow movements may be crucial in conserving this species.
Caecilia thompsoni es una especie endémica del Valle del Magdalena en Colombia y sobresale por alcanzar un gran tamaño corporal (1767 mm longitud total máxima). Con miras a resolver algunas dudas taxonómicas, estudiamos la variación de los surcos primarios, surcos secundarios, surcos interrumpidos por la cloaca, longitud del cuerpo, ancho a la mitad del cuerpo y largo/ancho. Examinamos 77 ejemplares provenientes de cuatro poblaciones dentro del Valle del Magdalena y encontramos que hay variación significativa en sentido occidente-oriente en las poblaciones húmedas (norte) y secas (sur). Por último hacemos una redescripción para la especie y discutimos sobre las dificultades taxonómicas que afectan actualmente al género Caecilia.
Natural history studies offer insights into the behavior and interactions of species in various environments, which are crucial for conservation and preservation. Pristimantis relictus is a newly described Robber Frog endemic to the isolated mountains of Ceará state, northeast Brazil. Limited information on its ecology is currently available. Herein we describe the feeding habits and microhabitat use of this species from three mountains in Ceará state. We also performed a literature review of the prey items consumed by other species in the genus Pristimantis in the Americas. In general, P. relictus is a generalist in terms of microhabitat use, foraging in herbaceous plants, on the ground, trees, and shrubs, and for diet, consuming a wide range of prey groups, with beetles and larvae the most common prey. This plasticity of dietary and microhabitat use may be crucial for the persistence and geographic distribution of this species, including their response to environmental changes. The large variety of prey categories utilized by species of Pristimantis suggests a generalist diet that may reflect prey diversity in the environment.
A investigação de aspectos biológicos fundamentais, como os hábitos alimentares de animais marinhos migratórios de longa distância, como as tartarugas marinhas, apresenta desafios significativos. Esses estudos são essenciais para identificar os locais de alimentação e as presas preferidas desses quelônios, fornecendo assim informações valiosas para embasar decisões de proteção do habitat. Analisamos o conteúdo do tubo digestivo de 132 espécimes de Caretta caretta encalhadas e/ou capturadas acidentalmente ao longo da costa do Golfo de Gabès, de 2004 a 2010. Os itens alimentares foram analisados usando o Índice de Importância Relativa (IRI), o Índice Alimentar de Geistdoerfer (Q) e o Índice Alimentar Principal (MFI) de Zander. Também categorizamos o lixo e calculamos sua frequência de ocorrência. A dieta da tartaruga-cabeçuda consistiu de 46 espécies de vários grupos zoológicos, refletindo sua distribuição flexível em zonas neríticas pelágicas e bentônicas. Observamos um padrão de alimentação comum para as espécies, com presas que habitam o fundo do mar, comuns em ambientes rasos. Moluscos, artrópodes e poríferos constituíram as principais presas, enquanto tunicados e peixes foram presas secundárias frequentes. Os equinodermos e as algas são presas secundárias acessórias e itens adicionais de segunda ordem, respectivamente. Moluscos e artrópodes foram ingeridos principalmente durante a primavera e o verão, enquanto tunicados e poríferos foram ingeridos durante os meses de outono e inverno. O tamanho da tartaruga não teve efeito sobre a diversidade da dieta ou a porcentagem de biomassa. Este estudo enfatiza o valor da análise da dieta para descobrir a ecologia alimentar e o uso do habitat das tartarugas-cabeçudas no Golfo de Gabès. Proteger e gerenciar essa região e garantir a presença de recursos tróficos pode ser crucial para manter as populações de tartarugas-cabeçudas e aumentar sua sobrevivência nas águas da Tunísia.
