Mario Humberto Yanez-Muñoz

The Neotropical tailed caecilians of the genera Epicrionops and Amazops (Rhinatrematidae) remain poorly known. Here, we examined their morphology, distribution, and molecular phylogenetic relationships using specimens from Ecuador. Our review of museum collections expands the empirical basis for understanding variation in these genera and reveals broader geographic and morphological diversity than previously recognised. Morphological and µCT-based analyses identified consistent diagnostic differences between Amazops and Epicrionops , particularly in annular counts and cranial bone configurations. We describe a new species of Epicrionops from the montane forests of southeastern Ecuador, characterized by a relatively small body size in fully metamorphosed individuals (174–317 mm); a maxillopalatine enclosing the orbit; a long spatulate posterodorsal process of the squamosal; an articular facet of the quadrate contacting the posterior end of the maxillopalatine but not the squamosal; a retroarticular process of the pseudoangular that is dorsally concave and ventrally convex; frontals with slightly notched anterior and posterior margins and curved lateral edges; and an os basale with a narrowing cultriform process and wavy, rounded margins. The pterygoid is large, attached to the maxillopalatine, and barely contacts the quadrate. Phylogenetic analyses of mitochondrial genes (12S, 16S, ND1) recovered the new species in a clade with E. marmoratus - bicolor , the only congeners for which molecular data are currently available. We report, for the first time, the phylogenetic position of the genus Amazops and also expand the known distribution of Amazops amazops . Our molecular data suggest that the genus is more diverse than currently recognized, identifying additional potentially undescribed species. These findings provide new integrative evidence on the morphological and phylogenetic diversity of Rhinatrematidae and highlight the need for broader sampling and integrative analyses in the tropical Andes.

Quantifying biodiversity patterns in remote Amazonian ecosystems remains constrained by the limitations of traditional field surveys. We combined passive acoustic monitoring (PAM), machine learning, and ecoacoustic metrics to assess the taxonomic and functional structure of bird communities along a riparian gradient in the Kapawi River, Ecuadorian Amazon. A total of 2,030 recording hours were acquired using 16 Autonomous Recording Units (ARUs) deployed along a river-to-interior forest gradient (0–800 m from the riverbank). Automated detection with BirdNET yielded 92,137 records corresponding to 379 bird species. Species richness was highest at the river edge (325 species), which also harboured the greatest number of unique taxa (71 species), while interior sites showed lower but more consistent local richness. Multivariate analyses showed clear spatial segregation between riparian and interior communities. Despite this turnover, the trophic structure remained highly homogeneous (>90% similarity), dominated by insectivorous and frugivorous guilds. Generalized linear models (GLMs) indicated strong positive associations between avian species richness and key ecoacoustic metrics, with particularly pronounced effects for the Acoustic Diversity Index (ADI) and the Bioacoustic Index (BI). Spatially explicit analyses further demonstrated marked heterogeneity in acoustic structure along the fluvial gradient, reflecting fine-scale variation in soundscape composition. Together, these findings show that riparian habitats structure avian communities primarily at the taxonomic level, while functional organization remains largely conserved across the gradient. This mismatch indicates that biodiversity components respond unevenly to environmental variation, with taxonomic richness being more sensitive than functional composition. Our results underscore the potential of ecoacoustic approaches as scalable, non-invasive tools for detecting spatial patterns in biodiversity and habitat-driven community assembly in tropical systems.

We explore the hidden diversity of the terrestrial frog genus Niceforonia , based on phylogenetic and morphological evidence, we describe two new species. Both species are found in pristine unexplored old-growth forest of the Andean slopes of Ecuador. Niceforonia dracula sp. nov., is only known from its type locality at the base of the iconic Cerro Golondrinas, located in the northwesternmost part of the Andes of Ecuador, Carchi Province. This new species is characterized by the presence of low occipital and dorsolateral folds, pale ventral coloration, greatly enlarged toe discs, and circunmarginal grooves in fingers and toes. Niceforonia quilloturo sp. nov. is known from several nearby localities in the upper Pastaza watershed, and is characterized by slightly enlarged tip in fingers and toes, presence of low occipital folds, plus small white pale pointy warts with dark belly and ventral surfaces. Ventral coloration is sexually dimorphic: dark brown with small white points in females and cream, yellow-orange peppered with small black flecks in males. Phylogenetic evidence is concordant with allopatric distribution in Niceforonia dracula sp. nov. and N. elassodiscus , while most of the taxa on the eastern of the Andes show parapatric distribution patterns, including Niceforonia quilloturo sp. nov., and related Niceforonia peraccai . Additional undescribed taxa are intermixed within Niceforonia nigrovittata , thus future systematic revision of the genus is needed.

The tropical Andes represent not only one of the most biodiverse regions on the planet, but also a center of diversification and endemism for the hyperdiverse genus Pristimantis . Our study contributes to resolving and updating the taxonomy of one of the most diverse clades within the genus, the Pristimantis myersi clade. Here, we describe two new species of this clade and provide insights into their morphology, phylogenetic position, and biogeography. During field campaigns in 2022 and 2023, led by the Instituto Nacional de Biodiversidad in Cotacachi, Imbabura Province, Ecuador, specimens were collected. These specimens were then analyzed using an integrative approach that combined external morphology and DNA sequencing to describe the two new species and update the phylogenetic framework of the P. myersi clade. Pristimantis cayapas sp. nov. is a small species distinguished by narrow spatulate toes, tympanum present, a short snout, and distinctive reddish inguinal coloration. Pristimantis dinardoi sp. nov. is a small species characterized by a visible tympanum, digital pads of fingers and toes wider than the digits, a heel with a conical tubercle surrounded by subconical tubercles, and groins with a range of vivid hues. Both species occur in high montane evergreen forests of the North western Ecuadorian Andes. Genetic distances also support their recognition as new species, with values exceeding 2.5% for P. dinardoi and 4% for P. cayapas when compared with their closest relatives. Our findings expand the known diversity of the P. myersi clade in the northern Andes of Ecuador and highlight the importance of integrative taxonomic approaches in disentangling cryptic lineages.

A new species of rain frog from the upper montane forest of the eastern Andes in the upper Pastaza watershed, Ecuador is described. Pristimantis fergusoni sp. nov . is characterized by its short snout, conical tubercles on upper eyelids and heels, combined with a scarlet colored belly in females. These unique traits differentiate the new species among other Pristimantis of upper montane eastern Ecuadorian Andes. Phylogenetic analyses support its validity and place it within a clade nested with other tuberculated species occurring along the Andean slopes. Pristimantis fergusoni sp. nov . is currently known from only two close localities (Cerro Candelaria and Chamana Reserves) at elevations between 2972 and 3200 m elevation, within the Llanganates-Sangay Ecological Corridor. Data Deficient IUCN status is proposed until new information is available. Individuals were observed at night perched on vegetation in herbaceous and arbustive vegetation of upper montane forest. This discovery contributes to a growing body of evidence identifying the upper Pastaza valley as a hotspot of amphibian endemism and diversification. With this addition, 30 strabomantid species are described for this region in the last decades, underscoring its conservation importance. This discovery highlights the urgent need for integrated taxonomic efforts combining fieldwork, morphology, and molecular data to resolve complex evolutionary relationships within the megadiverse genus Pristimantis , especially in underexplored high-elevation habitats of the tropical Andes. Finally, we provide an updated phylogeny for this clade that clarifies its evolutionary relationships.

Pristimantis , a genus of direct-developing frogs within the family Strabomantidae, comprises 617 recognized species, making it the most species-rich genus of vertebrates worldwide. This group include 264 described (43% of the world) species in Ecuador, being one of the countries in the region with the highest rate of species description, greatest diversity and endemism. In this study, we analyze the phylogenetic position and describe a new Pristimantis species from the Colonso Chalupas Biological Reserve and Llanganates National Park in northeastern Ecuador, using phylogenetic, genetic, morphological, and geographic evidence. Additionally, we propose a new subgenus within Pristimantis that includes the Pristimantis prolatus and Pristimantis bicantus species groups. Our results indicate that the new species and related species form a well-supported group with significant genetic divergence based on the 16S rRNA gene (average uncorrected p -distance = 2.8–7.5%), within the Pristimantis bicantus species group. Morphologically, the new species is characterized by a black to dark-gray dorsum and marbled venter (less intense or brown in males), being endemic to the Guacamayos mountain range and the Llanganates region in the northeastern Andean foothills of Ecuador. We emphasize the importance of including topotypic specimens to analyze and compare species groups to delimiting species, like Pristimantis .

Mera County is located in the eastern lowlands of the Llanganates–Sangay Connectivity Corridor (CELS) and is considered a priority conservation area due to the high degree of endemism and existing biological diversity. In the present study, we analyzed snake records from three databases as well as preserved specimens from two local informal collections, four formal collections, and five international collection databases with the participation of numerous students and citizen scientists. Collectively, we examined 85 years’ worth of material—666 individual records, representing seven families, 31 genera, and 66 species. We report seven species previously unrecorded in the study area and 14 new size and elevation records. Our results place this small county among the most snake‑diverse areas in the world. Our citizen‑science approach highlights the value of collaborative work and regional initiatives to involve local people and organizations (private, government, and universities) in scientific efforts.

Over the past decade, research in the montane forests of the Mira River basin, spanning Ecuador and Colombia, has identified it as crucial for the adaptive radiation of flora and fauna, shaped by its complex geological and climatic history. This study focuses on the phylogenetic and systematic revision of a frog clade initially labeled as Pristimantis verecundus, revealing significant cryptic diversity. Through detailed analyses of type material and expanded molecular sampling, we found that the original description actually included specimens representing two additional species, which are described herein. In this work, we discovered and formally described four new species within montane forests at elevations from 1,600 to 2,300 meters. Genetic distances of 3.34% to 14% and clear morphological differences underscore the clade’s hidden diversity. We propose renaming the group Pristimantis celator clade within Pristimantis myersi species group and subgenus Trachyphrynus, aligning with phylogenetic evidence and resolving taxonomic ambiguities using the oldest available name, Pristimantis celator (Lynch, 1976). This reclassification includes 14 species, seven formally described, and seven as candidates, distributed across northwestern Ecuador and southwestern Colombia, particularly in Mira and Esmeraldas River basins. The study highlights the Andean orogeny’s role in species diversification within Pristimantis celator clade, with geographic barriers like Cerro Golondrinas influencing genetic isolation. Genetic divergences exceeding 3.34% indicate evolutionary isolation across these landscapes. Our findings provide insights into montane ecosystem speciation, emphasizing vicariance, niche adaptation, and altitudinal gradients in shaping biodiversity. A polytomy among three well-supported clades within Pristimantis myersi species group is noted due to incomplete genetic data, yet distinctiveness and evolutionary relationships are affirmed. Cryptic diversity within Pristimantis celator clade links to unique orogenic and climatic conditions, highlighting conservation needs. Lastly, we provide a redescription of Pristimantis verecundus and species identification key to aid future research and conservation in this biogeographically influential region.

This document contributes 15 new items to the prey list of the genus Chironius in Ecuador, based on an examination of 89 specimens of seven Ecuadorian species. The results agree with previous reports of the genus Chironius on its feeding preference for small ectothermic prey, specifically anurans. Like other studies, data indicate that Chironius species inhabiting the lower Amazon basin have an extensive anuran diet consisting mainly of the most diverse group of anurans in the region, the family Hylidae. In contrast, species inhabiting the tropical Andes may be more specialized for the most diverse group of anurans in the region, the genus Pristimantis. The percentage of prey recorded according to their activity and habits suggests that species of the genus Chironius forage on their prey during diurnal and occasionally nocturnal periods. Only 13.4% of the material examined in this work presents stomach contents, which reflects the limitations of developing trophic studies on snakes with museum material and the restrictions of opportunistic observations.

We present a flora and fauna dataset for the Mira-Mataje binational basins. This is an area shared between southwestern Colombia and northwestern Ecuador, where both the Chocó and Tropical Andes biodiversity hotspots converge. We systematized data from 120 sources in the Darwin Core Archive (DwC-A) standard and geospatial vector data format for geographic information systems (GIS) (shapefiles). Sources included natural history museums, published literature, and citizen science repositories across 13 countries. The resulting database has 33,460 records from 6,821 species, of which 540 have been recorded as endemic, and 612 as threatened. The diversity represented in the dataset is equivalent to 10% of the total plant species and 26% of the total terrestrial vertebrate species in both hotspots. The dataset can be used to estimate and compare biodiversity patterns with environmental parameters and provide value to ecosystems, ecoregions, and protected areas. The dataset is a baseline for future assessments of biodiversity in the face of environmental degradation, climate change, and accelerated extinction processes.