TREES AS ECOLOGICAL TEMPLATES FOR TROPICAL LITTER ARTHROPOD COMMUNITIES

My dissertation spans five chapters on diverse topics on the ecology and taxonomy of ants in tropical regions. In Chapter 1, I explored if tree species identity explained litter arthropod biodiversity. In Chapter 2, I explored if tree species identity shape the structure of brown food webs. In Chapter 3, I reviewed the systematic status of the Neotropical ant genus Tatuidris. In Chapter 4, I conducted an experiment to explore the consecuences of high ant abundance in brown food webs. In Chapter 5, I explored mechanisms of ant species co-existence using trait- and phylogenetic-based test of community composition

Mapping continental Ecuadorian ant species

Ecuador is considered a megadiverse country but information on the distribution and conservation of its ant species is scarce and scattered through the literature. Here we review 150 years of published literature to assemble the first comprehensive species list of continental Ecuadorian ants (excluding the Galapagos Islands). Our main goals are to provide support to online tools (www.theantsofecuador.com), and to serve as a reference to the various research initiatives currently being done in the country. We found 2,124 ant records, from 679 ant species, in 180 localities, reported in 149 articles. We used a subset of this database (i.e. 1,111 records left after removal of duplicates and records with no locality info) to review the Ecuadorian regions, provinces, and national parks covered by the list. For a tropical country, both the number of records per ant species (mean=1.8, SD=1.9) and the number of ant species per locality (mean=6.2, SD=29.7) are extremely low. Moreover, the ant records in our list are biased towards three provinces (Orellana, 410 ant records and 378 ant spp.; Sucumbios, 212 and 177; Pichincha, 129 and 92), one region (Oriente, 779 records and 487 ant species) and non-protected areas (777 ant records and 510 ant spp.). Endemic ants are poorly covered by the Ecuadorian system of protected areas. This study highlights the gaps and opportunities in ant research for the country

New ant (Hymenoptera: Formicidae) records for Ecuador deposited at the Carl Rettenmeyer ant collection in the QCAZ Museum

Reportamos el depósito de 3 221 especímenes de hormigas, correspondientes a >150 especies de hormigas, en la colección Carl Rettenmeyer del Museo QCAZ, Sección Entomología, de la Pontificia Universidad Católica del Ecuador. Este material fue originalmente colectado en la localidad de Limoncocha (actualmente Provincia de Sucumbios, Ecuador), entre los años 1968–1973, por el Dr. Carl Rettenmeyer y sus colaboradores. Veintiocho especies de hormigas en esta lista son reportadas para el Ecuador por primera vez. Dado el tamaño y la edad de la colección, ésta constituye la más grande y antigua colección de hormigas para una localidad ecuatoriana, actualmente depositada en el País.Palabras Clave.- Limoncocha, Yasuni, Solenosis geminata, hormigas legionarias, nuevos registros

Clinical Correlation Between Computerized Tomography Findings and Pathologic Diagnosis in Patients Surgically Treated for Complex Renal Cysts in a Colombian Tertiary Center

IntroductionRecent data have reexamined the historical rates of malignancy observed in Bosniak IIF and III cystic lesions, and this has led to an endorsement of the use of active surveillance as the standard of care for Bosniak III renal cysts by affirming that overtreatment rates for this subgroup are close to 50%. In light of this, the present study describes the correlation between imaging studies and pathologic diagnosis in patients surgically treated for complex renal cysts in Colombia.Materials and methodsThis is a retrospective, descriptive, and observational study. We analyzed the medical histories of patients who had been surgically treated for complex renal cysts between 2010 and 2018 in the urology department of a tertiary center in Bogota, Colombia. The exclusion criteria were incomplete clinical histories and absent diagnostic images or their official interpretation.ResultsOut of the 235 urological procedures performed, nine were excluded. And 6.19% (n = 14) were cases of surgically treated complex renal cysts; 38.46% were compatible with Bosniak 46.15% were Bosniak III, and 15.38% were Bosniak IV. The percentage of renal cancer as revealed by the histopathological study was 60, 66.7 and 100 for renal cysts Bosniak IIF, III, and IV, respectively; 77.7% of these confirmed oncological cases had received a diagnosis of clear cell renal carcinoma.ConclusionsIn our study, the percentage of malignancy in patients with renal cysts Bosniak IIF and III was found to be greater compared to the findings in the recent medical literature. We believe that the management offered to the population with complex renal cysts in Colombia should be tailored to the individual risk characteristics of each patient

Green bottle flies (Calliphoridae, Luciliinae) of Ecuador: geographic distribution, checklist and DNA barcodes

Green bottle flies (Diptera, Calliphoridae, Luciliinae) comprise a diverse and cosmopolitan taxon, known from at least 1,500 species. They have become crucial elements in forensic investigations, as they spend part of their life cycle in decaying remains. Here, we review the distribution of eleven Luciliinae species in Ecuador: the monotypic Blepharicnema and ten Lucilia species. We identified specimens using morphological characters. Additionally, we DNA barcoded 43 specimens from three species using 658bp segments of the standard Cytochrome Oxidase I (COI) mitochondrial gen. Molecular and morphological identifications presented high correspondence, suggesting COI barcodes are an efficient tool for the identification of these three green bottle flies species. Geographical records are biased towards the northern Andean region, particularly near to large urban settlements. We remark the value to applied forensic research of continuous sampling of necrophagous flies under a variety of habitats and crime conditions.Fil: Moreno Coellar, Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina. Pontificia Universidad Católica del Ecuador; EcuadorFil: Amat, Eduardo. Tecnológico de Antioquia; ColombiaFil: Meneses, Pablo E.. Universidad Regional Amazónica Ikiam; EcuadorFil: Donoso, David A.. Escuela Politécnica Nacional; EcuadorFil: Barragán, Álvaro R.. Pontificia Universidad Católica del Ecuador; Ecuado

ED009. El uso de la ciencia ciudadana para determinar la distribución y prevalencia de la hormiga argentina Linepithema humile (Hymenoptera: Formicidae) en Quito, Ecuador

Invasive species are a serious threat to native biodiversity and ecosystem function, and invertebrates tend to make exceptionally good invasives through their ability to reproduce and disperse readily. A prevalent cosmopolitan invasive species that thrives in urban environments, is the Argentine ant (Linepithema humile). L. humile was first documented in 2014 but it has been present in the country for many years before that. This study sought to understand the distribution and prevalence of L. humile found within the Metropolitan District of Quito (MDQ). Considering the long period since its likely introduction we hypothesized that the population would be well-established and did not expect an increase in the prevalence of L. humile across its distribution. Over three years (2017-2019), we used citizen science by recruiting students from two different universities, to collect 535 samples from 471 sites across the MDQ. In total, L. humile made up 63.18 % of species collected, suggesting the species dominates the local ant community. Contrary to our predictions, the proportion of L. humile increased over time, from 48.96 % in 2017 to 67.37 % in 2019. Additionally, the proportion of “empty” vials, where no ants were found in the sampling site, decreased over time (from 21.88 % to 14.03 %), suggesting that L. humile increased its prevalence in the community and its abundance and distribution. Future analysis will include spatial analysis and the inclusion of new data to better understand how the distribution of L. humile may have changed over time.Las especies invasoras son una seria amenaza para la biodiversidad nativa y el funcionamiento de los ecosistemas, y los invertebrados tienden a ser excepcionalmente buenos invasores a través de su capacidad para reproducirse y dispersarse fácilmente. Una especie invasora cosmopolita prevalente que prospera en entornos urbanos es la hormiga argentina (Linepithema humile; Mayr, 1868). L. humile fue documentado por primera vez en 2014 pero ha estado presente en el país desde muchos años antes. El objetivo de este estudio fue entender la distribución y prevalencia de L. humile encontrada dentro del Distrito Metropolitano de Quito (DMQ). Teniendo en cuenta que el período transcurrido desde su probable introducción es muy largo, planteamos la hipótesis de que la población estaría bien establecida y no esperábamos un aumento en la prevalencia de L. humile en toda su distribución. Durante tres años (2017-2019), utilizamos la ciencia ciudadana al reclutar estudiantes de dos universidades diferentes para tomar 535 muestras de 471 sitios en todo el DMQ. En total, L. humile constituía el 63,18 % de las especies colectadas, lo que sugiere que la especie domina la comunidad local de hormigas. Contrariamente a nuestras predicciones, la proporción de L. humile aumentó con el tiempo, del 48,96 % en 2017 al 67,37 % en 2019. Además, la proporción de viales “vacíos”, donde no se encontró hormigas en el sitio de muestreo, disminuyó con el tiempo (del 21,88 % al 14,03 %), lo que sugiere que L. humile incrementó su prevalencia en la comunidad y su abundancia y distribución. Futuros análisis incluirán un análisis espacial y la inclusión de nuevos datos para comprender mejor cómo la distribución de L. humile puede haber cambiado con el tiempo

Hunting habits die hard: Conserved prey preferences in army ants across two distant neotropical rainforests

Army ants are widely recognized as keystone species in neotropical rainforests due to their role as important arthropod predators. Their large‐scale raids involve thousands of workers scouring the forest floor in pursuit of prey, primarily capturing other invertebrates. Up to 20 species of army ants coexist in a rainforest, and dietary niche differentiation has been proposed as a mechanism to alleviate competition among them. Based on only a handful of study sites, however, our understanding of the precise dietary preferences and the extent of niche differentiation remains notably limited. In this study, we aimed to expand our knowledge of army ant communities by resolving an Ecuadorian predation network consisting of 244 prey species and 13 army ant species representing the five known neotropical army ant genera: Cheliomyrmex, Eciton, Labidus, Neivamyrmex, and Nomamyrmex. We collected 2156 prey items from 180 army ant raids/emigrations, and of these, we identified 1945 prey items to the family level, 1313 to the genus level, and 664 to the species level based on morphological identifications and DNA barcodes. Prey consisted primarily of other ants (1843 prey items; 153 ant species), to the largest part ant brood (N = 1726). Hence, most army ant species chiefly plundered the nests of other ants, while the three swarm raiding species, that is, Lab. praedator, Lab. spininodis, and Ec. burchellii, exhibited a relatively high proportion of non‐ant invertebrate prey in their diet. The predation network showed a high degree of specialization (H2′ = 0.65), characterized by little dietary niche overlap among sympatric species. We compared the Ecuadorian network with one previously studied in Costa Rica and found that, despite the large geographic distance, prey preferences remained remarkably similar. We discovered species‐specific preferences for captured ant genera and species, despite some species turnover in both army ants and prey. Additionally, army ants also exhibited consistent spatiotemporal raiding preferences across study sites. In conclusion, predation preferences within army ant communities exhibited consistency in multiple niche dimensions across two distant neotropical rainforests, suggesting a notable level of predictability within army ant predation networks

Evolution of the Most Massive Galaxies to z ~ 0.6: II. The link between radio AGN activity and star formation

We analyze the optical spectra of massive (log M*/Msun > 11.4) radio-loud galaxies at z~0.2 and z~0.6. By comparing stellar population parameters of these radio-loud samples with radio-quiet control samples, we investigate how the presence of a radio-emitting jet relates to the recent star formation history of the host galaxy. We also investigate how the emission-line properties of the radio galaxies evolve with redshift by stacking their spectra. Our main results are the following. (1) Both at low and at high redshift, half as many radio-loud as radio-quiet galaxies have experienced significant star formation in the past Gyr. (2) The Balmer absorption line properties of massive galaxies that have experienced recent star formation show that star formation occurred as a burst in many of these systems. (3) Both the radio and the emission-line luminosity of radio AGN evolve significantly with redshift. However, radio galaxies with similar stellar population parameters, have similar emission-line properties both at high- and at low-redshift. These results suggest that massive galaxies experience cyclical episodes of gas accretion, star formation and black hole growth, followed by the production of a radio jet that shuts down further activity. The behaviour of galaxies with log M*/Msun > 11.4 is the same at z = 0.6 as it is at z = 0.2, except that higher redshift galaxies experience more star formation and black hole growth and produce more luminous radio jets during each accretion cycle.Comment: 14 pages, 12 figures, submitted to MNRA

Rapid ant community reassembly in a Neotropical forest: Recovery dynamics and land‐use legacy

Regrowing secondary forests dominate tropical regions today, and a mechanistic understanding of their recovery dynamics provides important insights for conservation. In particular, land‐use legacy effects on the fauna have rarely been investigated. One of the most ecologically dominant and functionally important animal groups in tropical forests are the ants. Here, we investigated the recovery of ant communities in a forest–agricultural habitat mosaic in the Ecuadorian Chocó region. We used a replicated chronosequence of previously used cacao plantations and pastures with 1–34 years of regeneration time to study the recovery dynamics of species communities and functional diversity across the two land‐use legacies. We compared two independent components of responses on these community properties: resistance, which is measured as the proportion of an initial property that remains following the disturbance; and resilience, which is the rate of recovery relative to its loss. We found that compositional and trait structure similarity to old‐growth forest communities increased with regeneration age, whereas ant species richness remained always at a high level along the chronosequence. Land‐use legacies influenced species composition, with former cacao plantations showing higher resemblance to old‐growth forests than former pastures along the chronosequence. While resistance was low for species composition and high for species richness and traits, all community properties had similarly high resilience. In essence, our results show that ant communities of the Chocó recovery rapidly, with former cacao reaching predicted old‐growth forest community levels after 21 years and pastures after 29 years. Recovery in this community was faster than reported from other ecosystems and was likely facilitated by the low‐intensity farming in agricultural sites and their proximity to old‐growth forest remnants. Our study indicates the great recovery potential for this otherwise highly threatened biodiversity hotspot