Revista de Biología Tropical / International Journal of Tropical Biology and Conservation, es una revista de acceso abierto completo de la Universidad de Costa Rica centrada en la biología tropical y la conservación. Todos los números, desde 1953 hasta la actualidad, están disponibles para su descarga gratuita. aquí. NUESTRO ENFOQUE (Objetivo) Nuestra revista publica artículos científicos que aumentan nuestra comprensión de la biología, la conservación y las ciencias biomédicas de la vida en los trópicos. Los criterios de selección son la cantidad y calidad de la nueva información y su interés potencial tanto para el público en general como para los especialistas. Los ecosistemas estudiados, o al menos los organismos, deben ser tropicales. COBERTURA TEMÁTICA Números regulares Damos preferencia a artículos de fondo que incluyen preguntas de estudio comprobables, por ejemplo, estudios con un diseño experimental que evalúe factores que influyen en variables biológicas, o estudios que explican los mecanismos subyacentes a fenómenos biológicos o biomédicos como, por ejemplo, el comportamiento o la fisiología. Los estudios de campo deben presentar patrones temporales o espaciales. También damos la bienvenida a estudios sistemáticos o filogenéticos por encima del nivel de especies, metanálisis y estudios bibliométricos que examinan críticamente lo que se conoce y lo que queda por hacer en cualquier campo de la biología tropical. Los artículos de revisión se publican en su mayoría por invitación del Consejo Editorial a autoridades reconocidas. Otros especialistas interesados en enviar una revisión primero deben enviar un esquema de manuscrito titulado al correo biologia.tropical@ucr.ac.cr. Las propuestas aceptadas reciben la misma evaluación que los manuscritos regulares. Todas las revisiones y metanálisis deben identificar y llenar los vacíos en el conocimiento, presentar avances metodológicos y proponer futuras direcciones de investigación. Nota sobre datos antiguos: Si su trabajo se basa en datos antiguos, recomendamos compararlos con datos más recientes, o usarlos como parte de meta-análisis, para darles mayor valor. Los estudios basados en datos recopilados hace más de seis años deben incluir una justificación de por qué siguen siendo de interés y, en el caso de estudios de campo, deben presentar patrones espaciales o tendencias temporales de importancia histórica. El Comité Editorial evalúa la validez de los métodos y la relevancia de los resultados antes de enviar el manuscrito a revisión. La revista ahora cuenta con un número al año (publicación continua del 1 de enero al 31 de diciembre) y publica los artículos la misma semana en la que se tiene disponible una versión editada. Hasta 2021 publico cuatro números regulares por año: número 1 (enero-marzo), número 2 (abril-junio), número 3 (julio-septiembre) y número 4 (octubre-diciembre). No publicamos notas; comunicaciones cortas; listas de especies; nueva especie única; extensiones de rango; nuevos registros y otros estudios preliminares o breves; o informes técnicos altamente especializados basados en protocolos (por ejemplo, estudios agrícolas, forestales, bioquímicos, microbiológicos, acuícolas, pesqueros o similares que solo aplican técnicas bien conocidas a casos particulares de interés local). NÚMEROS ESPECIALES Los números especiales financiados por organizaciones de investigación se aceptan después de la aprobación del Comité Editorial. Pueden contener una diversidad de tipos de informes, incluidos artículos breves, nuevos registros, nuevas descripciones de especies, listas de verificación, informes técnicos, etc. Para publicar un número especial, comuníquese con biologia.tropical@ucr.ac.cr para obtener una estimación de costos. PÚBLICO META Personas investigadoras con interés en el estudio de todos los campos de la biología tropical. PORQUÉ PUBLICAR EN LA REVISTA DE BIOLOGÍA TROPICAL? Totalmente indexada: Revista de Biología Tropical está incluida en Science Citation Index Expanded, REDIB Journals Ranking, Current Contents, Google Scholar, Biological Abstracts y alrededor de 50 otros índices internacionales. Rápida decisión y publicación (7 días para la primera decisión, 5-7 meses para aceptación definitiva, 6-8 meses desde el envío hasta la publicación). Razonable: utilizamos un sistema de doble ciego para una evaluación justa de los manuscritos. Alto impacto, no solo por su índice de citas, sino también porque es muy leído en países con la mayor biodiversidad tropical, lo que garantiza que su artículo tendrá el mayor impacto en la conservación de la biodiversidad tropical. Factor de impacto de Web of Science de 0.6. Factor de impacto en SJR de 0.28 (Q2). Un trato personalizado por parte de nuestro dedicado personal. Juntas editoriales y científicas de clase mundial. Acceso abierto: Todos los artículos, desde el primer número en 1953 hasta el presente, están disponibles gratuitamente en línea (Archivos), por lo que es más probable que sean citados que los artículos detrás de muros de pago. PUBLICACIÓN GRATUITA: Cada artículo recibe 10 páginas de espacio libre en formato PDF, que es suficiente para la mayoría de los artículos científicos. Se pueden publicar páginas adicionales diagramadas en el pdf a $50 cada una. Material complementario como textos adicionales, figuras, tablas, gráficos y bases de datos con un costo de $60. Póngase en contacto con biologia.tropical@ucr.ac.cr para obtener más información. OAI-PMH: https://revistas.ucr.ac.cr/index.php/RBT/oai
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Diversity of moths and butterflies of the southwestern region of Costa Rica
Introduction: The Costa Rican southwestern region is considered one of the neotropical biodiversity hotspots. This geographically isolated forest embraces a rich diversity of moths and butterflies, which is still unknown for the most part. Objectives: (a) Describe and compare the diversity of moths and butterflies among different localities of the southwestern Costa Rican region, and (b) identify information gaps in this group of insects. Methods: Data for this study were collected in 12 different localities by parataxonomists and taxonomists for the national inventory of biodiversity led by INBio (National Biodiversity Institute) using different trap types, but relying mainly on light traps. We compared alpha and beta diversity of moths and butterflies among the six localities (Cortés, Piedras Blancas, Rancho Quemado, Agujas, Los Patos, Sirena) with more extensive sampling. Results: The dataset consisted of 78 747 specimens, of which 2 096 were identified only to the order level. The remaining 76 650 specimens were classified to the family level (n = 48 families), genus, species, or morphospecies. Species and morphospecies were distributed across 37 families. The alpha and beta diversity varied across localities for the 12 families of moths and butterflies that were present in the six localities selected. In general, Piedras Blancas, Rancho Quemado, and Sirena stand out as the most diverse localities. The richness of species varied among different families. For most families Agujas, Los Patos, and Sirena contained more species, but some other families showed a different pattern. Conclusion: Differences in the diversity of moths and butterflies over a northern-southern gradient likely correspond to species (individuals within species) adapted to different biotic (e.g., availability of host plants and food resources) and abiotic (e.g., microclimatic conditions associated to the complex topography of the region) conditions. Despite the large effort made by INBio in knowing and mapping the biodiversity of Costa Rica, and the economic and biological importance of the biodiversity, there are still a huge number of species to be known, named, and properly used.
alpha diversity; beta diversity; moth and butterfly distribution; dissimilitude.
Copyright (c) 2025 Revista de Biología Tropical http://creativecommons.org/licenses/by/4.0
The diversity of bees (Hymenoptera: Apoidea) in heterogeneous tropical dry forest cover in Huila, Colombia.
Introduction: Tropical forests are one of the world's most biodiverse ecosystems. Tropical Dry Forests (TDFs) exhibit high levels of endemism reflected in their diverse flora and fauna; however, these ecosystems are under threat from human activity. Restoring TDFs ecologically is therefore essential for preserving their biodiversity. In this context, pollination is an essential ecosystem service that needs to be preserved due to its importance for the exchange of genes between vegetation communities. Objective: To characterize the diversity of the bee communities and their association with different types of cover. Methods: In three parcels (La Tribuna, Chaparral and San Francisco) of a fragment of BTS in the Department of the Huila, Colombia, sampling over an 11-month period was taken place from October 2021 and September 2022 using fixed trapping methods (essences and Van Someren-Rydon traps) and manual collection with an entomological net. Results: A total of 1 241 specimens were identified and classified into 74 species of bees from 15 genera for all cover types (vegetation). La Tribuna (representative of one of such TDF’s types) encompassed the highest diversity indices in all cases, while Chaparral (another vegetation type for TDFs) on the other hand, showed the lowest values. Permutational multivariate analysis of variance (PERMANOVA) analysis revealed significant differences in wild bees’ community composition between the three areas under evaluation, suggesting that level of TDF’s restoration impacts community structure. Indicator Value Index revealed seven morph-species with significant associations in total. These morph-species exhibited a high frequency and specificity when analyzed together on two of the cover types (La Tribuna and Chaparral). No indicator species exclusive to San Francisco (the third parcel of cover type) were detected. In terms of functional characteristics, most of the identified species of wild bees were solitary and nested in cavities or soil. A higher proportion of eusocial species were observed in La Tribuna. Conclusions: The ecological restoration of the Eco-Reserve is generating bee communities that are more diverse, functionally complex and structurally coherent, and that are consistent with advanced stages of TDF’s recovery.
Copyright (c) 2026 Revista de Biología Tropical https://creativecommons.org/licenses/by/4.0
Spread of invasive ginger Zingiber spectabile (Zingiberaceae) in successional and old-growth tropical forest
Introduction: Zingiber spectabile, a shade-tolerant ornamental ginger native to Southeast Asia, is invading tropical wet forest understories in Central America. This shade-tolerant species is of concern, yet no ecological impact or management assessment exists. Objective: To examine the invasion patterns of Z. spectabile in primary and secondary forests, reproductive capacity, effects on understory vegetation, and the effectiveness of control efforts. Methods: Field trials were conducted in 30-year-old secondary forest and in primary forest remnants in southern Costa Rica that were invaded by Z. spectabile, which was introduced to the region in the early 1990s. Control efforts consisted of aboveground biomass removal and herbicide application to rhizomes. Results: Both primary and secondary forests showed substantial invasion, but stem and inflorescence densities and aboveground biomass were three-fold higher in secondary forests, suggesting that secondary forests are more susceptible to invasion. Z. spectabile exhibited high reproductive capacity via prolific nodal sprouting (all cut stems producing 5.8 ± 0.3 rooted sprouts); inflorescences produced 64.3 ± 7.9 seeds each, yielding approximately 104 717 to 312 314 seeds/ha across invaded sites. Seed germination rates were similarly high in primary (58 %) and secondary (47 %) forests but lower in pasture (3 %). With one year of control efforts, Z. spectabile reinvaded, regaining over 35 % of aboveground biomass. During the first year following control, native herbaceous plant density increased by 61.5 % in secondary forest; there were no significant responses of woody seedlings or saplings in either forest type. Conclusions: These findings suggest that Z. spectabile invasion affects some components of understory plant communities, especially in secondary forests, and underscores the need for longer-term studies of invasion impacts and understory responses to control. Given the labor-intensive nature of biomass removal and the limited effectiveness of herbicides, improved and scalable management strategies are urgently needed.
Effects of biodiversity dimensions (phylogenetic, functional, and taxonomic) of frugivorous bats on the structure of ecological networks
Introduction: Mutualistic interactions between bats and plants can be organized into complex networks and analyzed using various metrics that have revealed the existence of interaction patterns among different networks. These patterns are shaped by the diversity of attributes, evolutionary history, and ecological processes within a community. Objective: To assess the influence of taxonomic, functional, and phylogenetic diversity on the structure of 12 plant-bat mutualistic networks. Methods: We constructed 12 plant-bat networks interactions and applied Pearson correlation analyses between diversity indices and network-level metrics. Nestedness, interaction strength asymmetry, specialization asymmetry, specialization, and modularity were used as the network metrics. Results: Our analysis showed that the network structure varied with diversity dimensions. Taxonomic indices revealed low Shannon diversity but high equitability. Functional and phylogenetic diversities were low. Higher species richness reduced nestedness, whereas stronger functional evenness increased interaction asymmetry. Sampling completeness was low (53.4 %), and correlations indicated that modular networks might support higher diversity. Conclusion: Taxonomic and functional diversity have a greater influence on network architecture, with the former specifically influencing the formation of modules and specialization, and the latter influencing network asymmetry. This result suggests that diversity indices may affect the interaction network properties in different ways.
Insights from DNA barcoding endangered endemic Caridina shrimps (Decapoda: Atyidae) in Lindu Lake, Indonesia
Introduction: Humanity faces a multidimensional crisis with severe threats to often poorly known freshwater biodiversity. Molecular tools, like DNA barcoding, can aid in biodiversity exploration, monitoring, and conservation. Sulawesian Caridina shrimps are both ecologically significant and endangered yet remain understudied. Objective: To contribute well-documented DNA barcode (COX1 mtDNA) sequences for three Caridina species endemic to Lindu Lake. Methods: We collected 224 Caridina shrimps from three sites around Lindu Lake in August (n = 73), and October 2023 (n = 117), and July 2024 (n = 34). We measured and analyzed morphological traits as dimensionless ratios of total length. We extracted DNA from six specimens (two per species) and COX1 mtDNA barcodes obtained through PCR (primers jgLCO and jgHCO) and Sanger sequencing. We obtained homologous sequences from GenBank (BLAST routine) and BOLD repositories for phylogenetic analyses. All molecular analyses were performed in MEGA 11. Results: One species was identified at each site. Morphological traits differ between species. Three haplotypes with low divergence: one in Caridina kaili, one in Caridina linduensis, and one in both Caridina dali and C. linduensis. Homologous sequences in GenBank and BOLD included very few Sulawesi endemic species; these formed the closest sister clades to Lindu Lake Caridina. Conclusions: We submitted to the GenBank repository the first reference DNA barcodes for each of the Lindu Lake Caridina species. The poor resolution of COX1 mtDNA for Lindu Lake Caridina may be due to recent evolutionary processes. Our study highlights the ongoing need for barcoding freshwater invertebrates, particularly atyid shrimps from Sulawesi, in the Wallacea bioregion.
atyid shrimps; Crustacea; cryptic species; lacustrine; mitochondrial DNA; Wallacea
Copyright (c) 2025 Revista de Biología Tropical https://creativecommons.org/licenses/by/4.0
Niche overlapping in Hypopachus (Anura: Microhylidae) and new record of Hypopachus variolosus in Central Mexico
Introduction: Microhylidae is one of the most diverse anuran families. The Hypopachus genus comprises a group of relatively unknown fossorial frogs distributed from the United States to Panama. To date, their environmental requirements and niche overlap among species remain unstudied. Objectives: To assess niche overlap among four Sheep Frog species, genus Hypopachus, and report a sighting of Hypopachus variolosus in the State of Mexico after 66 years with no records. Methods: We conducted fieldwork in Tonatico, State of Mexico, Mexico. The vegetation consists of low deciduous forest under a semi-warm subhumid climate. We modeled the environmental occupation of H. variolosus, H. ustus, H. barberi, and H. pictiventris through a principal component analysis and kernel density estimation, calculated niche overlap using Schoener’s D metric, and modeled the environmental suitability of each species using the maximum entropy algorithm. Results: On 25 October 2024, we captured a male H. variolosus measuring 25.4 mm. A significant niche overlap was detected only between H. variolosus and H. ustus. Preference for low temperatures distinguishes H. barberi from the other species, while preference for high precipitation regimes sets H. pictiventris apart. H. variolosus has the broadest distribution range, occurring from Texas to western Panama, followed by H. ustus, which ranges from the coasts of the Gulf of Mexico and the Pacific in Mexico to Nicaragua. H. barberi is distributed from the state of Chiapas, Mexico, to northern Nicaragua. The most range-restricted species is H. pictiventris, found from southeastern Nicaragua to western Panama. Conclusions: Our results suggest that meso- and microclimatic variables may play a key role in reducing competition among sympatric Hypopachus species. Additionally, the conditions of high temperatures and low rainfall that prevail in Mexico and Central America, favor the extensive distribution of H. variolosus and H. ustus.
Functional analysis of wood traits, soil, and aboveground biomass in Terra firme and Igapó forests
Introduction: Wood traits are intrinsic properties of variables used in aboveground biomass (AGB) models, such as wood density and maximum height, whose behavior may vary with soil nutrient availability. In recent decades, knowledge of functional trait ecology has become a valuable tool in biomass and productivity studies. Objective: To analyse the stocks and storage rates of AGB in tropical moist gallery forests of the Colombian Orinoquia (Tomo River, Vichada) based on wood traits and edaphic variables. Methods: We evaluated variables associated with functional and edaphic response on tree vegetation from permanent monitoring plots, three in Terra Firme and two in the floodplain (igapó). For this, we included measurements of wood traits from dominant species, calculated functional diversity indexes, and identified clustering patterns and functional strategies. Results: It was found that higher functional richness was associated with higher storage rates in both forest types. Quadratic entropy and functional dispersion showed similar trends to functional richness but were not statistically significant. Functional evenness and divergence showed contrasting patterns between forests. In both forests, acquisitive functional types had the highest AGB values. Fiber traits, such as fiber length, were associated with AGB, but parenchyma traits were not. We recognized that phosphorus is a nutrient driver of AGB. Conclusions: Our results demonstrate similar functional trends in igapó and terra firme forests.
Revealing chromosomal structure in trans-Andean Loricariidae: first cytogenetic characterization of the fish Lasiancistrus volcanensis
Introduction: The genus Lasiancistrus (Ancistrini) comprises four cis-Andean and five trans-Andean valid species distributed across trans-Andean, Amazonian, Orinoco, and Guianan drainages. No cytogenetic data are available for trans-Andean populations, limiting our understanding of their chromosomal organization and evolutionary history. Within Loricariidae, the only previous cytogenetic study in this region examined Transancistrus santarosensis from the Gulf of Guayaquil drainage, Ecuador. Objective: To present the first cytogenetic characterization of Lasiancistrus volcanensis, a species endemic to the trans-Andean Magdalena River basin, to describe its karyotype organization and explore its evolutionary implications within Loricariidae. Methods: Specimens were analyzed using Giemsa staining, C-banding, and fluorescence in situ hybridization (FISH) with CA(15) and CAA(10) microsatellite probes. Chromosome number, morphology, heterochromatin distribution, and microsatellite localization were determined. Results: The diploid number of L. volcanensis was of 2 n = 54 and a fundamental number of 108, with a karyotypic formula of 32 m + 18 sm + 4 st. Heterochromatic regions were concentrated in pericentromeric positions of several pairs, including large blocks on the first two pairs. Microsatellite signals were predominantly located in terminal chromosome regions. The predominance of meta- and submetacentric chromosomes, along with the conserved diploid number, supports the hypothesis of karyotypic stability in Loricariidae. Conclusions: These results expand the cytogenetic baseline for Loricariidae. The observed patterns suggest evolutionary conservatism in L. volcanensis. Broader cytogenetic and genomic surveys across its distribution are essential to elucidate the mechanisms underlying karyotype diversification in this species.
Challenges and opportunities of local engagement in coral restoration at Laughing Bird Caye National Park
Introduction: Numerous studies have revealed the importance of local support for successful restoration and conservation initiatives. Much less attention has been devoted to identifying the challenges and opportunities that influence community support. Objectives: To identify the challenges and opportunities influencing community engagement in coral reef restoration at Laughing Bird Caye National Park, Belize and its buffer zone. Methods: We interviewed restoration practitioners and key stakeholders, conducted a SWOT analysis with community members engaged in restoration efforts, and surveyed the broader public to evaluate local perceptions of the factors influencing community engagement in coral reef restoration. Results: Participant responses revealed four systems shaping local engagement: management, social, educational, and environmental. Key challenges included limited participation in restoration decisions, social dysfunction, low awareness of coral ecosystems, and environmental threats. Opportunities focused on expanding educational programs, particularly for youth, supporting local economies and livelihoods, promoting environmental stewardship, and strengthening governance through collaboration and local leadership. Conclusions: Our research revealed challenges that deter community engagement but also identified opportunities that may transform obstacles into actions to build trust, institutionalize collaborative participation, and empower local stewardship as a sustainable, community-driven process. Our results are specific to the community in Placencia, Belize but our methodology provides a potential roadmap for identifying stakeholder concerns and developing inclusive and effective programs to promote community engagement in restoration and conservation efforts elsewhere.
Participatory research methods; qualitative analysis; community engagement, Placencia, Belize, Caribbean, Laughing Bird Caye.
FragSize: using computer vision models to monitor massive coral fragment growth in a Caribbean coral nursery in the Seaflower Biosphere Reserve
Introduction: Monitoring the growth of coral fragments in restoration nurseries is essential for assessing their performance and the effectiveness of restoration interventions. Two-dimensional methods based on digital photography and ImageJ are commonly used, but their manual nature is time-consuming. Objectives: The aim of this study was to evaluate and test the performance of FragSizel, this open-source tool uses a computer-vision YOLOv8 segmentation model to automatically estimate the planar surface area of coral fragments from two-dimensional images. The evaluation of the performance of the model focused on assessing the degree of agreement between FragSize measurements and those obtained with traditional manual methods such as ImageJ. Methods: A YOLOv8 segmentation model was trained using photographs of fragments of D. labyrinthiformis, O. faveolata, and M. cavernosa that were kept an in-situ nursery at Nirvana Reef Garden, San Andrés Island (Colombian Caribbean). Agreement between FragSize and ImageJ measurements was assessed using Bland–Altman analyses. A total of 81 fragments of three species and 15 genotypes were measured across T0–T1 intervals ranging from 76 to 175 days. Results: Bland–Altman analyses showed strong agreement between FragSize and ImageJ, with low levels of bias and relative error in measurements performed at T₀ and T1 under both calibration methods evaluated. Conclusions: FragSize proved to be a reproducible tool for the automatic estimation of planar area in coral fragments from 2D images, showing agreement with ImageJ-derived measurements under both calibration strategies evaluated. Its open availability on GitHub facilitates its adoption in coral restoration programs requiring accessible and standardized methods for monitoring coral growth.
Caribbean; coral restoration; monitoring; computer vision
Extreme flooding, water quality and mass bleaching compounded impacts in wild and restored Elkhorn coral (Acropora palmata) populations in contrasting urban coral reefs in Puerto Rico
Introduction: Recurrent marine heatwaves, stronger hurricanes, and degraded water quality represent increasingly compounded threats to Caribbean coral reefs. These stressors may compromise the persistence of wild endangered Elkhorn coral (Acropora palmata) populations and the demographic performance of restored populations. Objectives: This study examined three climate-driven impact scenarios affecting A. palmata in Puerto Rico: (1) extreme rainfall and flooding from Tropical Storm Isaías affecting wild A. palmata colonies at the urban reef of El Escambrón; (2) compounded bleaching events during 2023–2024 affecting restored colonies at El Escambrón; and (3) the 2024 bleaching event affecting restored colonies at Punta Melones, Culebra, previously fragmented by Hurricane Beryl. Methods: Case 1 used line photo-transects from El Escambrón (2005-2022) to assess long-term spatial and temporal changes in benthic community structure and wild A. palmata populations. Cases 2 and 3 monitored restored colonies monthly across ten replicate plots per site, measuring survival, live tissue cover, size metrics, and colony condition. Coral metrics were correlated with water quality parameters. Results: Across El Escambrón and Punta Melones, A. palmata colonies experienced catastrophic mortality of 98–100% associated with recurrent thermal stress, low-salinity urban runoff pulses, and compounded bleaching. Sea surface temperature anomaly, 2024 Bleaching Alert Level 4 conditions, chlorophyll-a, particulate organic carbon, and dissolved oxygen were significantly associated with mortality. Conclusions: Coral mortality reflects combined acute and chronic stressors, especially in shallow reefs with degraded water quality and reduced thermal tolerance. With limited recruitment, increasing colony isolation, and low genetic diversity, the species may approach functional extinction without a refugia-based restoration framework.
Acropora palmata; marine heatwaves; mass bleaching; mortality; restoration
Higher bearded fireworm densities in structurally complex substrate do not increase predation on Acropora cervicornis (Lamarck, 1816) outplants
Introduction: In Puerto Rico, restoration efforts for the threatened coral Acropora cervicornis are increasingly affected by outbreaks of the corallivore bearded fireworm, Hermodice carunculata. However, limited knowledge of this polychaete’s population dynamics hinders effective management. Objectives: (1) Quantify the abundance and size distribution of H. carunculata across reef areas with different structural complexity; (2) Evaluate spatial and temporal variation in predation on A. cervicornis; (3) Examine relationships between fireworm abundance, predation, and macroalgal cover. Methods: The abundance and size distribution of H. carunculata were monitored across three reef areas (lowest to highest complexity) from March to November 2023. Bearded fireworms were captured using low-cost benthic traps. Predation activity was quantified by counting bite marks on coral outplants within fixed monitoring areas and on colonies outplanted outside the study areas from December 2022 to November 2023. Results: Bearded fireworm abundance was significantly higher in more structurally complex areas and varied over time, declining toward the end of the study period. In contrast, size distribution remained relatively stable across spatial and temporal scales. Predation rates on A. cervicornis outplants exhibited temporal and spatial variation; however, the number of predation marks was negatively correlated with bearded fireworm abundance. No significant relationships were detected between fireworm abundance and macroalgal cover or the presence of Dictyota dichotoma. Conclusions: H. carunculata tended to be more abundant in structurally complex habitats, supporting the influence of habitat structure on its distribution. However, inconsistent predation patterns and the unexpected negative correlation between bearded fireworm abundance and bite marks suggest that additional factors, including prey availability and behavioral dynamics, may shape predation activity. These findings provide insights into improving monitoring, management, and site selection in A. cervicornis restoration programs.
coral predation; corallivore; spatial heterogeneity; coral reef restoration; population dynamics.
Diversity and cultural value of the mastofauna associated with coffee plantations in Oaxaca, Mexico
Introduction: The expansion of conventional agriculture has caused the loss of natural habitats for the fauna, but the coffee agroecosystems of Oaxaca can provide an alternative habitat for mammals, which is associated with the cultural value that human communities assign to them. Objective: To assess the diversity and cultural value of medium and large mammals associated with the coffee plantation, and what they represent for the inhabitants of San Gabriel Mixtepec, Oaxaca, Mexico. Method: A mixed method was used. For the diversity analysis, the mammal species were identified through camera traps. To determine the Cultural Importance Index (IIC), semi-structured interviews and participatory workshops were carried out with the residents, who also helped to identify the different uses of the medium and large mammals. Results: A total of 26 species grouped into seven orders, 14 families, and 23 genera were recorded. Alpha diversity was greater in the dry season than in the wet season. Some species were detected in only one of the two seasons. Six hundred and thirty-nine records of cultural uses of mammals were obtained; use as food was the most mentioned. Twelve types of uses were identified. The species with the greatest cultural importance were Odocoileus virginianus (IIC = 0.92), with 11 uses, followed by Dasypus novemcinctus (IIC = 0.61), with 10 uses, Conepatus leuconotus (IIC = 0.60), with eight uses and Didelphis virginiana (IIC = 0.52), with 11 uses. Conclusion: The results show the importance that human residents assign to mammals associated with coffee agroecosystems, both for their use for subsistence and to complement the family economy. Furthermore, the residents themselves emphasize the importance of their traditional knowledge and the need to adopt sustainable management practices for the mastofauna, because they recognize the importance it has in the community and the benefits it can have on the environment.
mammals; Cultural Importance Index (IIC); coffee; agroecology; biocultural
Comparative osteology of the caudal skeleton and vertebral column of the freshwater fish Tlaloc (Cyprinodontiformes: Profundulidae)
Introduction: The family Profundulidae is a lineage of freshwater fish, with a limited geographical distribution extending from Southern Mexico to Central America, composed of two genera Profundulus and Tlaloc; the latter comprised only four species; however, studies based on the analysis of osteological characters are scarce for this family of fish. Objective: To describe the anatomy of the caudal bones and backbone of all species of the genera Tlaloc. Methods: A comparative analysis was performed on 44 cleared and stained specimens to identify the differences and similarities of backbone elements and the organization of the caudal skeleton among the species. Results: The comparison of the caudal skeleton in the species of the genus Tlaloc, revealed a very similar pattern in the morphology of the species; however, some characteristics were detected that may be useful for discrimination of species of the genus; the triangular shaped hipural plate is a characteristic that has only appeared in T. labialis, while in the rest of the species (T. candalarius, T. portillorum and T. hildebrandi), the hypural plate is fan-shaped. The total number of vertebrae, including the vertebral centrum, in the four species of the genus Tlaloc ranged from 33 to 38, of which 15-17 were abdominal vertebrae and 17-21 caudal vertebrae; T. portillorum had the lowest number of total vertebrae (33); while T. labialis had the highest number of total vertebrae (37-38) Conclusions: The consistent relationship to these skeletal elements suggests that the vertebrae and caudal fin ray count is a character of fundamental nature for the profundulid fishes, giving it particular taxonomic significance in that group.
caudal skeleton; endemic fish; morphology; Profundulidae; vertebrae
Acoustic characterization of the threatened bat Neoeptesicus innoxius (Chiroptera: Vespertilionidae) and two sympatric species in western Ecuador
Introduction: Bioacoustics allows the study of the ecology and behavior of bats through the analysis of echolocation signals. In insectivorous bats, foraging strategies, prey preference, and habitat use are closely related to the emission patterns of echolocation signals. Identifying significant bat habitats and improving conservation efforts can benefit from understanding these relationships. Objectives: To describe the echolocation signals of an endangered species Neoeptesicus innoxius, and other commonly detected species in the study area, Myotis nigricans and Molossus molossus, to contribute to the construction of a bat echolocation call reference library in Western Ecuador. Methods: Mist nets were used to capture bats, and reference recordings were subsequently obtained using the Anabat Swift ultrasonic detector. Echolocation pulse selection for each species was carried out using Kaleidoscope Pro 5.6.8 and BatSound 4.2.1, measuring the following spectral and temporal parameters of the echolocation signals in the search phase: initial, final, and maximum energy frequency, pulse duration, and interpulse interval. Results: N. innoxius presented the echolocation signals with the greatest variability of the spectral and temporal parameters, emitting pulses with high modulation speed (with one prominent FM component), and of low modulation speed (with one prominent QCF component); M. nigricans emissions were characterized by broadband signals of very short duration; and M. molossus presented alternation in its echolocation signals, where both high and low pulses had very little variability. Conclusions: The acoustic description of an endangered species like N. innoxius alongside the descriptions of other species frequently detected at the same study site, contributes to the construction of a bat echolocation call reference library. This input is the basis of future research of the ecology and behavior of the insectivorous bats that inhabit the Western Ecuador, which in turn is very valuable for designing tools and strategies for bat conservation.
insectivorous bats; echolocation; Isla Santay; Ecuador; Molossidae; Vespertilionidae.
Carbon capture in Chondracanthus chamissoi (Gigartinaceae) algal meadows: a case study on the Peruvian coast
Introduction: Algal meadows can significantly contribute to carbon (C) capture; nevertheless, few studies on Peruvian coast reserves are available. Evaluation of these stocks allows proposing better measures for the sustainable use of these habitats and maintaining their ecosystem services. Objective: To estimate biomass distribution and quantify the C captured as standing stock biomass in natural algal meadows of red algae Chondracanthus chamissoi on the Laguna Grande coastal lagoon (Ica-Peru), place of main extraction of these economically important algae. Methods: To calculate the biomass, the area occupied by each patch of algae in each sampling zone was delimited and transects perpendicular to the coast were used in randomly located plots. In the laboratory, the dry biomass and C content were measured (the latter using an elemental analyzer). Results: Monthly variation in the distribution and area was identified. September 2021 presented the highest total biomass (50 416.4 kg; 50.4 t) and C captured (13 t C or 47.58 t CO2) while from February to June no algal biomass was found. Differences were found in the biomass and C capture in the sampling zones, the months of C capture, and the interaction between these two variables. C capture decreases with warm months and more intensive anthropogenic extraction of algae. Conclusions: This study highlights the interaction between the anthropogenic extraction of C. chamissoi and seasonal environmental changes, alongside the net contribution of macroalgal biomass.
assimilation of carbon; blue carbon; red algae; sustainable extraction.
Coral reefs cover only about 3% of the ocean’s surface yet support approximately 33% of marine biodiversity. They also generate substantial economic benefits, with an estimated spillover value of $350,000 per hectare per year (Costanza et al., 2014). Despite their ecological and economic importance, nearly 90% of coral reefs are currently under threat, primarily due to anthropogenic pressures (Souter et al., 2020). This alarming situation has created an urgent need to implement effective policies for their protection and restoration, prompting global initiatives such as the UN Decade on Ecosystem Restoration (UN, 2021).
Effects of landscape structure on bird diversity in the Upper Magdalena Valley, Colombia
Introduction: Understanding the effects of landscape structure and composition on bird diversity is essential to identify distribution drivers and evaluate potential impacts of land use changes. Landscape structure refers to the spatial arrangement and organization of elements within a landscape and can be described using metrics such as the number and size of patches, their connectivity, and the degree of landscape heterogeneity. Objectives: In this study, we investigated the effects of landscape structure on the taxonomic diversity of bird assemblages in the Upper Magdalena Valley, Colombia. Methods: The study was conducted in 15 localities between June and November 2018, 2019, and 2022. We used mist nets and visual and audio surveys to evaluate bird community structure. This data was complemented with records from the eBird platform. A total de 17 565 individuals representing 401 species were recorded. We measured alpha and beta taxonomic diversity. Landscape structure was characterized by using a variety of metrics at patch, class, and landscape level using Geographic Information Systems (GIS). Results: We found a negative effect of landscape heterogeneity on taxonomic diversity. Our results indicate that landscape transformation leads to a reduction in bird diversity. In contrast, non-fragmented landscapes may have the potential to support taxonomically diverse bird assemblages, characterized by the presence of specialist species with a more restricted distribution. Conclusions: These findings highlight the susceptibility of specialist bird species to landscape change and highlight the importance of protecting and conserving natural areas to maintain taxonomic diversity of bird communities. Bird taxonomic diversity was influenced by landscape components such as landscape heterogeneity and patch perimeter, which had a negative effect on species abundance and richness.
Temporal variation of macroinvertebrate diversity in a high Andean microbasin in the south American tropics
Introduction: The study examines the aquatic biodiversity of macroinvertebrates in the Alambi River, in Ecuador and analyzes how human intervention has influenced the physico-chemical composition of the water and macroinvertebrate communities among 2000 and 2021. Methods: Physical and chemical data were collected, and pH, conductivity, dissolved oxygen, dissolved solids, and temperature were measured. The macroinvertebrates were obtained by means of "Surber", "D" and "kick" type nets. Three indices were used: BMWP, (Biological Monitoring Working Party), ABI (Andean Biotic Index) and (EPT) (Ephemeroptera, Plecoptera and Trichoptera). Cluster analysis, principal components and canonical analyses were also performed. Results: Taxonomic diversity increased significantly between 2000 and 2021, with an increase in the entire group of taxa. Diversity indices varied similarly between years, Simpson from 0.82 to 0.89 in 2000 versus 0.74 to 0.85 in 2021. Shannon in 2000 (2.20 to 2.45) and in 2021 (1.93-2.47). The completeness of the sampling was similar in both years, 81 vs 77 %, respectively. The structure of the macroinvertebrate community was more heterogeneous overall in 2021. There is a change in the sequential pattern in the turnover of communities in the direction of flow, which varies in 2021. The width of the river decreased in 2021. The average speed of the river also decreased from 1.12 m/s in 2000 to 0.52 m/s in 2021. The pH of the water increased slightly (7.8 to 8.1). Dissolved oxygen increased significantly from 66 % to 80 %. Conductivity and dissolved solids increased at all stations in 2021. The physico-chemical variables varied in their importance over the years, the most relevant being dissolved oxygen, total solids, and altitude, associated with good quality indicator families. The quality indicators in general demonstrated good watershed quality maintained over time, despite changes in both land use and human population growth. Conclusion: The Alambi basin has important changes in the composition and structure of aquatic invertebrate communities, however, it generally maintains good physical, chemical and biotic conditions that support the processes for maintaining the integrity of the basin.
Environmental DNA exploration of fish diversity in the Balantak River, Central Sulawesi, Indonesia
Introduction: Freshwater ecosystems play a crucial role in supporting human life, providing many ecosystem services. Species diversity is a valuable indicator for evaluating ecosystem health, gaining a broader perspective on ecological richness and ecosystem functions, but data are lacking for many rivers. Objectives: To obtain baseline data on the upstream and downstream ichthyofauna of the Balantak River, Banggai Regency, using environmental DNA (eDNA) with a focus on diadromous species. Methods: We collected, filtered and preserved water samples from upstream and downstream sites on the Balantak River followed by eDNA analysis (DNA extraction, PCR with MiFish 12S rRNA primers, Illumina sequencing, MitoFish bioinformatic analysis at 97 and 99 % identity thresholds) to produce taxonomically assigned Actinopteri amplicon sequence variants (ASVs). Results: Our data are consonant with the expected dominance of diadromous and euryhaline taxa (75 %), high Gobiiformes biodiversity, and differences between upstream and downstream ichthyofaunal communities. Reads were assigned to Actinopteri ASVs from 12 orders, predominantly Gobiiformes, Anguilliformes, and Centrarchiformes. The 15 assigned families included Anguillidae, Eleotridae, Gobiidae, Rhyacichthydae, Kuhliidae, and Terapontidae. Of the assigned genera (17 at 97 % and 25 at 99 %), Anguilla had the most reads (39.9 %), and Sicyopterus had the most ASVs (8). Conclusions: These baseline data demonstrate the usefulness of eDNA metabarcoding for exploring ichthyofaunal biodiversity in small tropical watersheds while highlighting gaps in 12S rRNA sequence databases, reinforcing the need for integrative taxonomic research in Sulawesi watersheds and reliable reference databases. Most assigned taxa are vulnerable to exploitation for food and/or the ornamental fish trade. Four non-native taxa from Cichlidae, Cyprinidae and Clariidae are considered invasive. Implications for conservation include the need to address the unregulated and largely unreported freshwater ornamental trade and introduction of non-native invasive species.
Plants that allocate more resources to flower production yield more fruit at local and global scales
Introduction: The internal mechanisms of plants and their interactions with the environment determine flower and fruit production. Several hypotheses have been proposed to explain these processes, emphasizing resource limitations, interactions with pollinators, selective abortion, the characteristics and positions of hermaphroditic flowers, and the influence of environmental variables on plant function. Objectives: This research aims to evaluate whether a high allocation to flowers positively affects the fruit production of hermaphroditic plants, as predicted by the pollinator attraction hypothesis, or whether it negatively correlates, as suggested by the selective abortion hypothesis. Methods: Both a local (Medina, Colombia) and a global database, based on the biomass of flowers and fruits collected using fruit traps were used to determine the possible relationship between the variables. The Medina database included data from 5-10 individuals for each of the seven plant species studied, with entire flowering and fruiting periods monitored. The global dataset encompassed 92 locations across 10 counties in Latin America, 2 in Europe, 2 in Africa, 2 in Asia and 1 in Oceania. This database compiled information on the total biomass of flowers and fruits of different plant species produced over at least one annual cycle. Results: The plant species studied and the global analysis revealed a positive relationship between flower and fruit production, supporting the pollinator attraction hypothesis. Although we did not quantify the biomass of aborted fruits, we found no evidence to suggest that high flower production results in an excess of ovules that cannot develop, as predicted by the selective abortion hypothesis. Conclusions: These findings suggest that plants have evolved allocation mechanisms for flower production that align with the potential for fruit development.
Urbanization as a driver of change: Differential ecological patterns of native and non-native parrots (Psittaciformes: Psittacidae) in an urban tropical city
Introduction: Parrots and related birds (i.e., Psittacidae, hereafter “parrots”) include species that often establish non-native populations in cities. However, little is known about their species-specific ecological patterns to urbanization in tropical cities. Objectives: To analyze changes in species richness, abundance, and composition across different urbanization levels and to compare abundance trends of most abundant species regarding built-up, grass and tree cover at different spatial scales (i.e., 200, 500, 1 000 m) for parrots in Medellín, Colombia. Methods: Parrot surveys were conducted from September 2021 to February 2022 (using transects, n = 10) and July 2023 to August 2023 (using point counts n = 220). Parrot abundance patterns were analyzed with Generalized Linear Models (GLMs), selecting the significant variable and best models based on Analysis of Variance (ANOVA) and Quasi-Akaike Information Criterion corrected (QAICc), respectively. Results: We recorded ten parrot species; six of them were non-native (i.e., outside their natural range of distribution): Eupsittula pertinax, Ara spp. and Amazona spp. The remaining four were native species: Brotogeris jugularis, Forpus conspicillatus, Pionus chalcopterus, and Psittacara wagleri. B. jugularis, F. conspicillatus and E. pertinax were the most abundant species, B. jugularis increased its abundance in areas with higher urbanization levels and F. conspicillatus in areas with lower levels. E. pertinax showed higher abundances in areas with medium to high urbanization levels (51-75 %), but it showed relationships with lower statistical power. Conclusions: Our finding suggest that the parrot assemblage in Medellín is mainly represented by non-native species in richness and composition, but native species are more abundant. Acknowledging these differences in ecological patterns in species can help improve urban wildlife management in tropical cities.
First assessment of the physiological performance of nursery corals in the Galápagos Islands: seasonal impacts on Pocillopora (Scleractinia: Pocilloporidae) growth
Introduction: Coral communities in the Galápagos Islands persist under highly variable oceanographic conditions driven by seasonal upwelling and ENSO-related thermal anomalies, which have historically constrained reef development and recovery. Following the 1982–83 El Niño event (~97 % coral mortality), recovery has been slow and fragmented. Despite this, Pocillopora remains the dominant reef-building genus in the central-southern archipelago and a key target for restoration. However, it remains unclear how seasonal thermal variability influences coral performance in nursery settings. Objective: To evaluate how seasonal thermal variability affects the growth, survival, and condition of Pocillopora corals in nursery settings in the Galápagos, in order to inform restoration strategies. Methods: Coral communities were assessed in Puerto Villamil Bay (Isabela Island), and 12 Pocillopora morphotypes were propagated in rope nurseries. Fragments were monitored using photographic records, and surface area was measured with ImageJ. Absolute, relative, and specific growth rates were calculated, along with mortality and tissue condition (% dead, bleached, and algal cover). In situ temperature data and El Niño 1+2 anomalies were incorporated to characterize thermal variability. Results: The coral community was dominated by Pocillopora (73.6 %, n = 3 569 colonies). Temperatures ranged from 18.7 to 30.1 °C under La Niña conditions. Fragment size increased more than fourfold (from 6.40 ± 2.51 to 27.75 ± 15.85 cm²), with an overall survival rate of 80 %. Growth exhibited strong seasonal patterns: relative and specific growth rates were higher during the warm season, while absolute growth was greater in the cold season. However, the cold upwelling period was associated with reduced overall performance, including higher mortality, tissue loss, and algal overgrowth. Significant differences among morphotypes were observed. Conclusions: Coral gardening is viable in the Galápagos, although seasonal cooling imposes important constraints. Restoration strategies should prioritize resilient morphotypes and account for seasonality to optimize outcomes in marginal reef systems.
coral gardening; thermal stress; La Niña, intraspecific variation; Eastern Tropical Pacific; coral physiological condition.
Beyond the crest: quantifying coastal protection and risk mitigation services of submerged reefs in the Mexican Caribbean
Introduction: Coral reefs function as natural coastal defenses by dissipating wave energy and reducing flooding and erosion. While the protective role of emergent reef crests is well documented, the contribution of submerged reefs remains poorly quantified. This study evaluates the coastal-protection function of two submerged reefs (Manchoncitos I and II) offshore Playa Paraíso, Quintana Roo, Mexico. Objectives: (1) quantify wave height reductions associated with submerged reefs; (2) compare wave propagation under reef and no-reef scenarios; and (3) assess the sensitivity of wave attenuation to changes in reef roughness. Methods: Numerical modeling (WAPO/REFDIF) was used to simulate wave transformation across the reef platform. A high-resolution bathymetric grid (4 × 3 km; 5 m) was developed using multibeam surveys, satellite-derived bathymetry, and in situ measurements. Simulations compared reef and no-reef scenarios and evaluated two Nikuradse roughness values (ks = 0.5 and 1.5 m). Results: The reefs generated local reductions in significant wave height ranging from 0.5 to 1.5 m. Manchoncitos I produced the greatest attenuation, whereas Manchoncitos II exhibited a more heterogeneous response, including localized wave-focusing effects. Increasing reef roughness enhanced wave-height reductions and expanded the spatial extent of wave dissipation. Wave attenuation varied according to reef geometry, roughness, and incident wave direction. Conclusions: Submerged reefs provide measurable coastal-protection services by reducing wave energy reaching the shoreline. Reef morphology and roughness strongly influence attenuation patterns. These findings support reef conservation and restoration to reduce coastal risk.
Coral reefs; wave attenuation; numerical modeling; reef roughness; Nikuradse (ks).
Early-life history traits of Thalassoma bifasciatum in Culebra, Puerto Rico
Introduction: The study of labrid otoliths has contributed significantly to our understanding of life histories of tropical reef fish. Life history theory is based on the effect on lifetime reproductive success (i.e., fitness), growth, mortality rates, age at maturity, reproductive output, and particularly for reef fish age and size at settlement of pelagic larvae to benthic juveniles. Objective: Quantify age and larval growth at settlement, subsequent length, and body condition of Thalassoma bifasciatum. Methods: Two hundred T. bifasciatum individuals were collected from Punta Maguey, in Culebra, Puerto Rico. One hundred individuals were euthanized for otolith dissection. Results: Otolith analyses revealed settlement ages ranging from 10 to 37 days and estimated standard length of 9–20 mm at settlement. Growth analyses demonstrated a significant positive relationship between age and length, while length – weight regression revealed a negative allometric growth, where length increases at a faster rate than body mass (b < 3). Additionally, Fulton’s condition factor declined with the increasing length. Conclusions: This study highlights early life history and growth patterns in T. bifasciatum in Culebra, PR and underscores the need for further exploration of life history traits to better understand population dynamics of tropical reef fishes. The rapid settlement observed in our study may be attributed to elevated water temperatures, suggesting that environmental drivers play a critical role in shaping recruitment and growth. This emphasizes the importance of incorporating environmental drivers when evaluating recruitment and population structure.
coral reef; otolith; aging; condition factor.
Nature-based solutions for nutrient removal in tourism wastewater: pilot bio-gardens with red mangrove (Rhizophora mangle) and water hyacinth (Eichhornia crassipes) at Iberostar Bávaro, Dominican Republic
Introduction: Wastewater from coastal tourism operations often retains residual nitrogen and phosphorus after conventional secondary treatment, contributing to nutrient enrichment in adjacent marine ecosystems. Nature-Based Solutions (NbS) have been proposed as low-cost polishing strategies that integrate ecological processes into wastewater management. Objective: To evaluate the short-term nutrient attenuation potential of Rhizophora mangle and Eichhornia crassipes in constructed bio-gardens installed downstream of hotel wastewater treatment systems under operational conditions. Methods: Four concrete bio-gardens (3.0 × 1.2 × 0.6 m) were installed downstream of an on-site wastewater-treatment facility in the Dominican Republic. Three units were planted (replicated treatments units) and one was left unplanted (control). Phase 1 evaluated R. mangle under continuous flow using treated effluent. Phase 2 evaluated E. crassipes under similar hydraulic conditions using enriched influent to simulate elevated nutrient loads. Water samples were analyzed for phosphate, total phosphorus, nitrate–nitrogen, and total nitrogen over a 48-hour hydraulic retention period. Results: During Phase 1, R. mangle exhibited limited short-term nutrient attenuation consistent with early-stage system stabilization. In Phase 2, E. crassipes demonstrated substantial short-term phosphorus removal and moderate nitrogen attenuation under enriched conditions, whereas the unplanted control showed minimal change. Conclusions: Plant-based bio-gardens can be physically integrated into hotel wastewater systems and may contribute to nutrient-load reduction when appropriately designed and managed. The contrasting short-term dynamics observed between species highlight functional complementarity under different loading scenarios rather than direct species superiority. These findings support further investigation of NbS as tertiary polishing modules within sustainable tourism infrastructure.
Nature-based solutions; Rhizophora mangle; Eichhornia crassipes; nutrient removal; wastewater treatment; tourism; Caribbean.
Diversity analysis of Chironomidae from the Andean-Amazonian transition (Caquetá, Colombia): a regional perspective
Introduction: The family Chironomidae is one of the most diverse and abundant groups of aquatic macroinvertebrates in aquatic ecosystems. Objective: To analyze Chironomidae's composition and diversity in the Caquetá department's Andean-Amazonian corridor, Colombia. Methods: Three study zones (Andean, Transition, and Amazonian), each with ten sampling stations, were selected. We conducted four field campaigns to collect biological material and record riverscape characteristics. We assessed alpha diversity using Hill numbers, a set of diversity measures providing a unified framework for diversity analysis. We also analyzed beta diversity by considering species richness differences and turnover. Using multivariate RDA analysis, physical and chemical variables of the riverscape contrast with taxonomic composition and beta diversity. Results: 36 chironomid taxa were identified, with the subfamily Chironominae and the genera Cricotopus, Chironomus, Larsia, and Polypedilum standing out. Hill numbers showed differentiation in Shannon-Wiener diversity (q1) and inverse Simpson diversity (q2), but richness (q0) showed less variation across study zones. The most significant component of beta diversity was species richness differences. Current velocity, total dissolved solids (TDS), vegetation cover, and substrates of sandy and vegetative origin (roots, aquatic macrophytes), as well as other components of the riverscape, significantly influenced species composition and beta diversity. Conclusions: Significant genus level information is provided for the Chironomidae family in the Andean-Amazonian region of the department of Caquetá, revealing dissimilarity among the study areas driven by differences in richness, as a measure of taxonomic beta diversity. Moreover, these findings indicate that the transition region functions as an ecotone for Chironomidae, serving as an intermediate zone between the Andes and the Amazon.
Bryophytes of Quindío: community composition, diversity, and structure across altitudinal gradients and heterogeneous habitats
Introduction: Bryophyte diversity in the Northern Andes is high compared with the Central Andes and other tropical regions, yet regional documentation remains uneven; therefore, department-level inventories are essential for biogeography and conservation. Objectives: To update the bryophyte inventory of the Quindío Department (Central Andes of Colombia) and describe species richness, taxonomic composition, substrate preferences, and altitudinal distribution. Methods: We integrated published and herbarium records with field surveys across six municipalities and nine localities. Sampling encompassed four elevational belts (premontane 970–1 600, montane 1 600–2 400, upper Andean 2 400–3 200, and paramo 3 200–4 200 m.a.s.l.) and five substrates (epiphytic, terricolous, lignicolous, rupicolous, and epiphyllous). Microclimatic variables were recorded in situ during sampling using a thermo-hygrometer (air temperature and relative humidity) and a lux meter (illuminance). Taxonomy and nomenclature were standardized using specialized literature and international databases. Results: We recorded 474 species (82 families, 198 genera): 276 liverworts, 195 mosses, and three hornworts, plus eight subspecies and 15 varieties. Richness was highest on epiphytic substrates (303 spp.), followed by terricolous (242), lignicolous (225), rupicolous (113), and epiphyllous (50) substrates. Lejeuneaceae was the most diverse family (76 spp.); among mosses, Fissidentaceae (17 spp.) and the genera Fissidens (13 spp.) and Campylopus (10 spp.) were prominent. Richness was concentrated in montane and upper Andean forests, with pronounced turnover among substrates and elevational belts. Conclusions: The bryophyte inventory of Quindío was updated to 474 species (82 families, 198 genera). Community composition showed high turnover, driven primarily by microhabitat/substrate filters (with peak richness in epiphytes) and, at the regional scale, by the elevational gradient, providing a baseline to guide monitoring and targeted sampling in underrepresented units.
Histological development of fish larvae Piaractus orinoquensis (Characiformes: Characidae) with emphasis on mouthparts
Introducción: El proceso de desarrollo larval es una etapa crítica en los sistemas de producción acuícola por la mortalidad que se presenta, debida a la temperatura, patógenos y la alimentación, entre otros. El suministro adecuado de alimento en cada etapa es uno de los inconvenientes más frecuentes dado el desconocimiento del desarrollo bucal en la transición de larva a juvenil que permita la toma de decisiones sobre manejo alimenticio, eficiencia del alimento y disminución de riesgos de pérdida durante esta fase del cultivo. Objetivo: Describir el desarrollo histológico de larvas de cachama blanca Piaractus orinoquensis con énfasis en el aparato bucal, durante la transición de larvas a alevinos. Métodos: Se tomaron muestras en diferentes estadios desde las 0 hasta las 763 hpe (horas post eclosión), registrando los diferentes cambios morfológicos por medio de histología convencional, microscopía óptica de alta resolución y microscopía electrónica de barrido, para un posterior análisis de imágenes con el software ImageJ®. Resultados: Las cachamas muestran ontogenia indirecta y son especies altriciales, debido a que muestran escasas reservas vitelinas cuando inician la alimentación exógena, como se evidenció a las 187 hpe con cambios significativos en el aparato bucal, pero sin contenido estomacal, posiblemente por inmadurez del sistema digestivo y la falta de suministro de alimento en esta etapa, factores asociados al manejo del cultivo, lo que incrementa el riesgo de mortalidad y escaso crecimiento de las larvas en relación directa con la alimentación. Conclusión: Los productores deben mejorar el proceso de larvicultura, al sincronizar los tiempos de traslado de la incubadora y de preparación del estanque, como estrategias de alimentación temprana para equilibrar la eficiencia económica con el desarrollo y la demanda metabólica de las larvas, mejorando así los índices de supervivencia y el rendimiento en los sistemas de producción piscícola.
larviculture; high-resolution optical microscopy; feeding; jaw.
Multi-temporal coral reef structure and health of Tayrona National Natural Park, Colombian Caribbean
Introduction: Coral reefs are biodiversity-rich ecosystems increasingly threatened by disease and, in particular, mass bleaching events driven by elevated sea-surface temperatures. Objectives: To assess spatio-temporal variation in reef structure and coral health across three reef zones within Tayrona National Natural Park (TNNP) from 1998 to 2023. Methods: Coral cover (CC), algal cover (AC), and coral health (CH: bleaching and diseases) were quantified following the protocols of the Colombian Coral Reef Monitoring System. Results: In Gayraca, mean CC was 37.05 %, dominated by massive corals with a declining trend. Mean AC was 43 %, and turf algae increased significantly through time. Black band disease and white plague were recorded with < 2 % incidence. In Chengue, mean CC was 30 % (massive corals), with disease incidence around 2 %, and the mean AC was 44 %. In Granate, mean CC was 28.2 %, largely massive corals with a downward trend, while mean AC was 47 %, dominated by turf algae with an increasing trend. Stony Coral Tissue Loss Disease (SCTLD) was not detected. Conclusions: Bleaching increased sharply in 2023, reaching unprecedented levels. Across bays, we observed a tendency toward lower CC and higher AC in areas closer to human populations. Although disease prevalence across years was high, annual disease incidence remained low and did not track thermal stress, suggesting comparatively high biological robustness of local coral populations.