Víctor Romero

Arbuscular mycorrhizal fungi (AMF) can enhance plant establishment in degraded drylands, but inoculation outcomes may depend on inoculum identity and recipient soil conditions. We evaluated the response of Piscidia carthagenensis to three native AMF consortia from contrasting successional stages of a xerophytic shrubland and to a non-native Acaulospora lacunosa inoculum. Plants were grown in soils representing reference shrubland, early-seral, and late-seral stages. An uninoculated treatment was included as a control. After 112 days, plant growth, nodulation, and AM root colonization were assessed. The magnitude and pattern of plant responses to inoculation varied among the three recipient soils. Native consortia generally produced more consistent positive effects on growth and nodulation than the non-native inoculum, particularly in seral soils. Total root colonization exceeded 90% in inoculated plants grown in early- and late-seral soils, yet plant responses still differed among inocula. Intraradical structures differentiated among inocula more clearly than total root colonization. Home inoculations showed trait-specific advantages over Away inoculations and more consistently outperformed the tested non-native inoculum. These findings suggest that the native AMF consortia evaluated here are promising candidate inocula for the restoration of degraded dryland ecosystems.

Distributional gaps in poorly documented Neotropical mammals often reflect the combined effects of ecological filtering, low detectability, taxonomic uncertainty, and incomplete sampling. We reassessed the documented distribution of L. brachyotis (Dobson, 1879), a rarely collected forest-dwelling phyllostomid bat, using an expanded occurrence dataset and specimen-based validation. Independently, we used ecological niche models to characterize climatic suitability under current and paleoclimatic conditions. We compiled 125 documentary or specimen records from published sources and museum material, including new voucher-based records from southern Ecuador and northern Colombia, and consolidated them into 121 reviewed unique locality-coordinate units. After environmental screening and cell-level deduplication, 115 unique presence cells were used for model calibration. The best-supported model used linear, quadratic, and hinge features with a regularization multiplier of 2.5 and performed significantly better than null-model expectations. Under current conditions, climatic suitability was broad but spatially heterogeneous across northern South America, with additional suitable areas in Mesoamerica, the Andean–Amazonian interface, central Brazil, and southeastern Brazil. Temporal projections identified recurrent areas of climatic suitability across northern South America, but were interpreted as climatic context rather than direct evidence of historical occupancy or demographic continuity. The new records indicate that the documented distribution remains incomplete along its margins. Our results support a revised interpretation of L. brachyotis as a rarely recorded humid-forest bat with a coherent Amazonian–Guianan core and peripheral extensions consistent with the combined influence of climatic suitability, habitat heterogeneity, and incomplete sampling.

Distributional gaps in poorly documented Neotropical mammals often reflect the combined effects of ecological filtering, low detectability, taxonomic uncertainty, and incomplete sampling. We reassessed the documented distribution of L. brachyotis (Dobson, 1879), a rarely collected forest-dwelling phyllostomid bat, using an expanded occurrence dataset and specimen-based validation. Independently, we used ecological niche models to characterize climatic suitability under current and paleoclimatic conditions. We compiled 125 documentary or specimen records from published sources and museum material, including new voucher-based records from southern Ecuador and northern Colombia, and consolidated them into 121 reviewed unique locality-coordinate units. After environmental screening and cell-level deduplication, 115 unique presence cells were used for model calibration. The best-supported model used linear, quadratic, and hinge features with a regularization multiplier of 2.5 and performed significantly better than null-model expectations. Under current conditions, climatic suitability was broad but spatially heterogeneous across northern South America, with additional suitable areas in Mesoamerica, the Andean–Amazonian in-terface, central Brazil, and southeastern Brazil. Temporal projections identified recurrent areas of climatic suitability across northern South America, but were interpreted as climatic context rather than direct evidence of historical occupancy or demographic continuity. The new records indicate that the documented distribution remains incomplete along its margins. Our results support a revised interpretation of L. brachyotis as a rarely recorded humid-forest bat with a coherent Amazonian–Guianan core and peripheral extensions consistent with the combined influence of climatic suitability, habitat heterogeneity, and incomplete sampling.

Background: The ecological dynamics between Trypanosoma parasites and their wild mammalian hosts, such as bats and armadillos, are complex. Recent 18S rRNA metabarcoding studies have reported extraordinary levels of hidden parasite diversity and frequent multi-lineage coinfections within individual wild hosts. However, the boundary between genuine biological coinfection and methodological artifact remains difficult to establish. Based on Gause’s principle of competitive exclusion, the mammalian bloodstream represents a highly constrained niche where stable coexistence of identical ecological competitors is theoretically rare. We hypothesize that previously reported hyper-diverse Trypanosoma coinfections are largely bioinformatic artifacts, and that true intra-host dynamics instead favor single-lineage dominance. Methods: To test this hypothesis, we sequenced samples from 27 wild armadillos ( Dasypus novemcinctus ) and 26 bats from Ecuador. The 18S rRNA gene was amplified via nested PCR and sequenced using an Oxford Nanopore Technologies MinION platform. We developed a progressively stringent bioinformatics pipeline to evaluate coinfection hypotheses. Raw reads were processed through three alignment scenarios: Lenient, Moderate, and Conservative. These scenarios modulate sequence identity, mapping quality (MAPQ), and coverage thresholds to effectively isolate true biological signals from alignment ambiguity. Results: Under lenient alignment parameters, the resulting profiles mirrored previous literature, exhibiting massive apparent intra-host multi-lineage diversity. However, as bioinformatic stringency increased to conservative thresholds (≥ 98% sequence identity, ≥ 99% coverage, and MAPQ ≥ 30), artifactual pseudo-coinfections collapsed. The highly restricted dataset demonstrated overwhelming single-lineage dominance, validating only three active mixed infections out of the retained samples. Furthermore, our rigorous pipeline isolated rare but genuine biological signals, including the detection of Trypanosoma cruzi marinkellei —historically considered a bat-restricted subgenus—within the terrestrial armadillo cohort. We also confirmed the presence of T. cruzi DTU III (TcIII) in Ecuadorian armadillos, representing a significant biogeographical record for the region. Conclusions: Once methodological noise is computationally stripped away, active multi-strain Trypanosoma coinfections in the host bloodstream are revealed to be ecologically anomalous. Our findings strongly support the principle of competitive exclusion, suggesting established lineages actively suppress competitors. While Oxford Nanopore sequencing offers necessary resolution for wildlife parasitology, fine-tuning algorithmic parameters is critical to accurately represent host-parasite networks and prevent the artificial inflation of intra-host diversity metrics. Author summary: Previous studies using DNA metabarcoding have reported that wild mammals, such as bats, frequently harbor complex communities of multiple Trypanosoma parasite lineages simultaneously. However, ecological principles suggest that identical competitors struggle to coexist stably within a constrained environment like the host bloodstream. To investigate whether these reported high coinfection rates reflect true biology or methodological artifacts, we sequenced the 18S rRNA gene of Trypanosoma from 26 bats and 27 armadillos in Ecuador. We processed the sequencing data through computational pipelines with progressively stricter filtering parameters. We observed that under lenient filtering, animals appeared to have highly diverse, mixed infections. Conversely, when strict parameters were applied to remove potential analytical noise, the artificial complexity collapsed, revealing that the vast majority of hosts were dominated by a single parasite lineage. We confirmed only three active mixed infections in our highly restricted dataset. Our findings indicate that active multi-strain Trypanosoma coinfections are rare, aligning with the principle of competitive exclusion. These results highlight the necessity of applying rigorous bioinformatic filters to accurately evaluate host-parasite interactions and avoid overestimating diversity metrics.

The Ecuadorian Mountain Viscacha (Lagidium ahuacaense) is an endemic rodent known only from its type locality in south-western Ecuador. Between 2017 and 2023, we conducted surveys guided by Geographic Information Systems and targeted field searches to update its known distribution and conservation context. Using a radiating search strategy from the first colony confirmed outside the type locality, combined with remote observations, camera trapping, and diagnostic signs, such as latrines, browsed vegetation, and vocalizations, we documented 16 colonies distributed across five municipalities in Loja Province. All confirmed colonies were associated with small, spatially isolated rocky outcrops. Most confirmed sites occur outside formally protected areas and are exposed to multiple overlapping threats, including wildfires, free-ranging dogs, livestock, tourism, and infrastructure-related activities. Our findings indicate that L. ahuacaense is an endemic species with a highly restricted distribution, whose persistence depends on a small number of vulnerable rocky refuges embedded within a heavily modified landscape. We briefly summarize conservation measures already underway, including the creation of municipal conservation areas and targeted fire-management actions, and outline priorities for future research and management. To minimize additional risks, we report localities at a coarse spatial scale.

Tropical forest canopies harbor exceptional biodiversity, yet basic aspects of the ecology and reproductive biology of many canopy‐dwelling animal species remain poorly understood. This gap is particularly evident for small nocturnal arboreal mammals, which are challenging to study using conventional methods. Here, we used arboreal camera traps in a tropical mountain rainforest in Southern Ecuador to document flower visitors to the mass‐flowering tree Handroanthus chrysanthus . Over a 16‐month period, our recordings provided new information on the nocturnal and seasonal activity patterns of a group of Spix's night monkeys ( Aotus vociferans ). In this study, we report the first evidence of flower feeding on H. chrysanthus and suggest that seasonal activity patterns may be more closely aligned with the primate's reproductive timing than with peaks in floral resource availability. These findings demonstrate the power of arboreal camera traps for studying elusive canopy species and provide new insights into the behavior, feeding ecology, and reproductive biology of owl monkeys in the wild.

We assessed non-volant medium- and large-sized mammals in a Mauritia flexuosa-dominated wetland within the Los Achales Reserve (southern Ecuadorian Amazon) between January and July 2023. We applied a multi-evidence approach that combined direct observations, tracks and signs, camera trapping, and 37 semi-structured interviews with Shuar residents, yielding 242 field records and 77 hunting reports. Field surveys recorded nine species, while interviews added four additional taxa, for a total of 13 species documented in the study area. The most frequently detected species was Dicotyles tajacu (n = 72). Diversity was moderate (Shannon H′ = 1.812; Simpson 1 − D = 0.800), with assemblage structure dominated by a few disturbance-tolerant taxa. Our results highlight the complementarity of local ecological knowledge and conventional field methods in improving species detection, particularly for elusive taxa. The observed assemblage is consistent with patterns of habitat loss and hunting pressure reported in human-modified Amazonian landscapes. Agricultural expansion, urban encroachment, and sustained hunting likely represent the main drivers of mammal population declines in Los Achales. These findings underscore the need for targeted research and conservation actions, including participatory monitoring approaches, to support the persistence of mammal communities in this underrepresented Amazonian wetland system.