Filogeografía, filogenia y especiación críptica en los Hormogastridae

Hormogastridae Michaelsen, 1900 es una familia de lombrices de tierra endémica del Mediterráneo Occidental con 32 especies y subespecies descritas de tamaños mediano agigante. Mientras que su biología y ecología son poco conocidos, sus relaciones filogenéticas han recibido una atención significativa en la última década. Empleando técnicas moleculares, los trabajos de Novo y colaboradores alrededor de 2010 destacaron la necesidad de una revisión sistemática de la familia debido a la no-monofilia de subgénero principal Hormogaster, y también descubrió la diversidad críptica de la morfoespecie H. elisae. Esta tesis identifica las principales cuestiones abiertas por los trabajos anteriormente mencionados, y propone nuevas aproximaciones conceptuales y metodológicas para incrementar nuestro conocimiento del grupo.En el Capítulo II se describe una nueva especie (Hormogaster joseantonioi):su posición filogenética como taxón hermano del complejo Hormogaster elisae matiza el aislamiento geográfico de esta última en el centro de la Península Ibérica y esclarece la posible ruta de colonización de su área de distribución actual. Esta especie mostró también combinaciones de caracteres internas desconocidas previamente, ampliando nuestra comprensión de la diversidad morfológica en hormogástridos..

Características de los fluidos de fractura para mantener la arena en suspensión durante el fracturamiento hidráulico

En la presente investigación se presentó la utilización de un fluido lineal base agua de fractura con carga polimérica mínima de 15 Lb/Mgal para su utilización como gel activado en las operaciones de fracturamiento hidráulico en el noroeste del Perú, dependiendo del diseño y propiedades requeridas del pozo a fracturar. Para ello se comparó las propiedades de un fluido base agua con distintas cargas poliméricas que mejor se apropie al diseño requerido. Se evalúan distintas características como: 1. Propiedades Reológicas: Se refiere al comportamiento reológico del fluido lineal a diferentes cargas poliméricas. 2. Activación de Gel: Conocido como un gel croslinkeado o gel activado que es el gel lineal formado por monómeros y gracias a un activador une sus cadenas formando polímeros. 3. Decantación de Arena: Se refiere a la capacidad del fluido de fractura para acarrear y mantener en suspensión a la arena de fractura, propante o también llamado agente sostén durante un determinado tiempo que debe ser no menos al tiempo de bombeo. 4. Ruptura del Gel: Se refiere a la degradación del gel activado, es decir vuelva a las propiedades reológicas de un fluido lineal. Se presentó un fluido lineal base agua cuya carga polimérica mínima es de 15 Lb/Mgal teniendo en cuenta el promedio de la profundidad de las etapas de fracturamiento hidráulico en el noroeste del Perú es de 4000 ft representando un BHST (static bottom hole temperature) (de 124 °F)

Diels-Alder cycloadditions in water for the straightforward preparation of peptide–oligonucleotide conjugates

The Diels-Alder reaction between diene-modified oligonucleotides and maleimide-derivatized peptides afforded peptide–oligonucleotide conjugates with high purity and yield. Synthesis of the reagents was easily accomplished by on-column derivatization of the corresponding peptides and oligonucleotides. The cycloaddition reaction was carried out in mild conditions, in aqueous solution at 37°C. The speed of the reaction was found to vary depending on the size of the reagents, but it can be completed in 8–10 h by reacting the diene-oligonucleotide with a small excess of maleimide-peptide

Macroecological inferences on soil fauna through comparative niche modeling: The case of Hormogastridae (Annelida, Oligochaeta)

Ecological Niche Modeling (ENM) through MaxEnt and quantitative comparison techniques using ENMtools could facilitate ecological inferences in problematic soil dwelling taxa. Despite its ecological relevance in the Western Mediterranean basin, the ecology of the endemic family Hormogastridae (Annelida, Oligochaeta) is poorly known. Applying this comparative approach to the main clades of Hormogastridae would allow a better understanding of their ecological preferences and differences. One hundred twenty-four occurrence data belonging to four clades within this earthworm family were used as input to infer separate MaxEnt models, including seven predictor variables. Niche breadth, niche overlap and identity tests were calculated in ENMtools; a spatial Principal Components Analysis (sPCA) was performed to contrast with the realized niches. The highly suitable predicted ranges varied in their ability to reflect the known distribution of the clades. The different analyses pointed towards different ecological preferences and significant ecological divergence in the four above-mentioned clades. These results are an example of wide-scale ecological inferences for soil fauna made possible by this promising methodology, and show how ecological characterization of relevant taxonomic units could be a useful support for systematic revisions

Systematic revision of Gatesona (Crassiclitellata, Lumbricidae), an endemic earthworm genus from the Massif Central(France)

The Massif Central in France could potentially harbor numerous ancient endemic lineages owing to its long history of continuous geological stability. Several endemic earthworm species inhabit the area, with Allolobophora (Gatesona) chaetophora, Helodrilus (Acystodrilus) and Avelona ligra showing hints of a common evolutionary origin. However, the phylogenetic relationships and taxonomic status of the species remain to be studied through integrative molecular and morphological methods. To this end, eight species including most of the known species and subspecies of All. (Gatesona), Helodrilus (Acystodrilus) musicus, and Avelona ligra were sequenced for a set of five molecular markers. The species were grouped on the basis of the molecular findings in a phylogenetic framework. All. (Gatesona) was included within the same clade as Helodrilus (Acystodrilus) and Avelona, separated from Allolobophora sensu stricto, supporting its status as a good genus. Branch lengths and average pairwise genetic distances suggested the subspecies of All. (Gatesona) chaetophora examined should be considered species-level taxa. Thus, a generic diagnosis for Gatesona stat. nov. is provided, along with redescriptions of Gatesona chaetophora comb. nov., Gatesona rutena comb. nov. stat. nov., Gatesona lablacherensis comb. nov. stat. nov. and Gatesona serninensis comb. nov. stat. nov. The study findings highlight the need for further sampling of earthworm diversity in the Massif Central (and Southern France), in addition to an increased focus on the Eastern European species of Helodrilus

Novel tumor-targeted self-nanostructured and compartmentalized water-in-oil-in-water polyurethane-polyurea nanocapsules for cancer theragnosis

Encapsulation of water-soluble bioactive compounds for enabling specific accumulation in tumor locations, while avoiding premature clearance and/or degradation in the bloodstream, is one of the main hallmarks in nanomedicine, especially that of NIR fluorescent probes for cancer theragnosis. The herein reported technology furnishes water-dispersible double-walled polyurethane-polyurea hybrid nanocapsules (NCs) loaded with indocyanine green (ICG-NCs), using a versatile and highly efficient one-pot and industrially scalable synthetic process based on the use of two different prepolymers to set up the NCs walls. Flow cytometry and confocal microscopy confirmed that both ICG-loaded NCs internalized in monocyte-derived dendritic cells (moDCs). The in vivo analysis of xenograft A375 mouse melanoma model revealed that amphoteric functionalization of NCs' surface promotes the selective accumulation of ICG-NCs in tumor tissues, making them promising agents for a less-invasive theragnosis of cancer

How to thrive in unstable environments: Gene expression profile of a riparian earthworm under abiotic stress

Nowadays, extreme weather events caused by climate change are becoming more frequent. This leads to the occurrence of extreme habitats to which species must adapt. This challenge becomes crucial for species living in unstable environments, such as the riparian earthworm Eiseniella tetraedra. Its cosmopolitan distribution exposes it to various environmental changes, such as freezing in subarctic regions or droughts in Mediterranean areas. Transcriptional changes under cold and desiccation conditions could therefore shed light on the adaptive mechanisms of this species. An experiment was performed for each condition. In the cold experiment, the temperature was lowered to −14 °C ± 2 °C (compared to 8 °C for control samples), and in the desiccation treatment, humidity was lowered from 60% to 15%. Comparisons of gene expression levels between earthworms under freezing conditions and control earthworms revealed a total of 84 differentially expressed genes and comparisons between the desiccation experiment and the control yielded 163 differentially expressed genes. However, no common responses were found between the two treatments. The results suggest that E. tetraedra can acclimate to low temperatures due to the upregulation of genes involved in glucose accumulation. However, downregulation of the respiratory chain suggests that this earthworm does not tolerate freezing conditions. Under desiccation conditions, genes involved in cell protection from apoptosis and DNA repair were upregulated. In contrast, lipid metabolism was downregulated, presumably to conserve resources by reducing the rate at which they are consumed

Guess who? Taxonomic problems in the genus Eiseniella revisited by integrated approach

Eiseniella neapolitana is a semi-aquatic, diploid earthworm that for many years was related to the cosmopolitan species Eiseniella tetraedra and even considered a subspecies of it. Norealidys andaluciana was described in Spain and is usually synonymized with E. neapolitana. We collected 69 specimens from Italy, Spain, and Cyprus and studied fve molecular markers (COI, 16S, 28S, 12S, and ND1) and their morphology to solve this taxonomic problem. Phylogenetic analyses reveal the possible existence of two separate genera confounded under the name Eiseniella, but the study of more molecular markers and species of the genus would be necessary to confrm this. Therefore, the synonymy between Eiseniella and Norealidys is maintained. Various genetic analyses, including species delimitation, confrm the separation between E. neapolitana and E. andaluciana (=N. andaluciana) and excluded that E. neapolitana is a subspecies of E. tetraedra. The resemblance in external appearance despite clear genetic diferences of the three species could be explained by convergent adaptation to the aquatic habitat. Despite the expected low haplotype diversity based on the 28S gene, we found a surprisingly high variability in the E. andaluciana (=N. andaluciana) population in Spain. However, its stable predicted secondary structure and its high content of G+C reject the presence of a pseudogene

Evaluating the conservation status of a North-Western Iberian earthworm (Compostelandrilus cyaneus) with insight into its genetic diversity and ecological preferences

In spite of the high conservation value of soil fauna, the evaluation of their conservation status has usually been neglected. This is more evident for earthworms, one of the most important ecosystem service providers in temperate habitats but rarely the subject of conservation research. These studies have not been developed in Western Europe, which comprises high diversity and several early-branching, relic genera. One potentially menaced representative of this fauna is Compostelandrilus cyaneus; this risk can be assessed by implementing potential distribution modeling and genetic diversity monitoring to their known populations. Genetic barcoding was performed in representatives of four populations (three of them newly sampled) in order to estimate genetic diversity and population genetics parameters. Ensemble species distribution models were built by combining several algorithms and using the five more relevant bioclimatic and soil variables as predictors. A large amount of genetic diversity was found in a small area of less than 20 km2, with populations located in less managed, better-preserved habitats showing higher genetic variability than populations isolated from natural habitats and surrounded by anthropic habitats. Potential distribution appears to be strongly restricted at a regional scale, and suitable habitats within the extent of occurrence appear fragmented and relatively limited. In addition, the main variables determining the ecological niche of C. cyaneus suggests a vulnerability to climate change and increasing soil compaction. Based on this knowledge, this species was assessed as Critically Endangered following the IUCN Red List of Threatened Species criteria, and some potential conservation actions are suggested.Ministerio de Ciencia, Innovación y Universidades | Ref. PGC2018-095851-B-C66Ministerio de Ciencia, Innovación y Universidades | Ref. FJCI-2017-32895Xunta de Galicia | Ref. ED431B 2019/03

Scherotheca Bouche 1972

Genus Scherotheca Bouché, 1972 Scherotheca Bouché, 1972: 279. TYPE SPECIES. — Lumbricus gigas Dùges, 1828. DIAGNOSIS. — Lumbricidae of medium to giant size, post-clitellar trapezoidal section. Pigmentation ranging from absent to dark brown. Prostomium epilobous, closed. Longitudinal furrows in the peristomium. Nephridial pores “en solfège” (irregularly distributed). Spermathecal pores in at least two intersegments, between 9/10 and 13/14, or 12/13 and 18/19, sometimes multiple. Anterior septa strongly thickened. Male pores in ½ 15, usually with porophores. Gizzard in 17-20 (21, 22). Typhlosole pinnate. Two or four pairs of seminal vesicles in (9, 10) 11, 12. DISTRIBUTION. — The genus Scherotheca is known (from the eastern to the western limits of its range) from Northeastern Italy, Tuscan Archipelago, Corsica Island, Mediterranean continental France and Spanish Catalonia, Southwestern France and part of the Spanish Cantabrian mountains.Published as part of Marchán, Daniel Fernández, Domínguez, Jorge, Hedde, Mickaël & Decaëns, Thibaud, 2023, The cradle of giants: insights into the origin of Scherotheca Bouché, 1972 (Lumbricidae, Crassiclitellata) with the descriptions of eight new species from Corsica, France, pp. 107-128 in Zoosystema 45 (3) on pages 110-111, DOI: 10.5252/zoosystema2023v45a3, http://zenodo.org/record/768129