The skull of the semi-aquatic neotropical lizard Echinosaura horrida (Gymnophthalmidae: Cercosaurinae) reveals new synapomorphies within Gymnophthalmoidea.

The rough teiid or water cork lizard (Echinosaura horrida) is a small reptile from Colombia and Ecuador placed in a genus that contains eight species and well-known phylogenetic relationships. Here we provide a detailed description and illustrations, bone by bone, of its skull, while we discussed its intraspecific variation by comparing high-resolution computed tomography data from two specimens and the variation within the genus by including previously published data from Echinosaura fischerorum. This allowed to propose putative diagnostic character states for Echinosaura horrida and synapomorphies for Echinosaura. In addition, our discussion includes broader comparisons of new character transformations of the jugal, vomer, orbitosphenoid, and hyoid. These characters are important for diagnosing clades at different levels of the Gymnophthalmoidea phylogeny.

Economic utility of Colombian Romosinuano cattle.

The objective of this study was to quantify the economic utility in Romosinuano production systems by developing a bioeconomic model assumed cow-calf, cow-calf plus stocker (CCPS), and complete cycle operations. Each system produced males for sale and females for replacement. Input parameters were established from breed data collected by AGROSAVIA. Revenues were estimated using the official cattle price, and production costs were quantified per activity. In the results, for cow-calf operations, the maximum economic utility was 244.12 USD. CCPS, yielded 231.86 USD, and Complete cycle, 268.94 USD. The genetic progress per generation for W240, W480, W24 and CI was + 3.8 kg, + 5 kg, + 5.9 kg, and -1 d, respectively. The price of livestock was the sensitized variable with the greatest impact on maximum economic utility (± 118.64 USD to ± 155.44 USD), followed by mineral supplementation (16.31 USD to ± 37.34 USD). The sensitized variables with the lowest impact were food (± 1.62 USD to ± 1.8 USD) and health plan supplies (± 6.03 USD to ± 9.13 USD). It is concluded that economic utility defined as a composite trait influenced by the characteristics that shape it favors genetic progress and the identification of animals with optimal performance in different bovine production systems.

Quality, acceptability and usability of self-sampling kits used by non-healthcare professionals for STI diagnosis in Spain: a single-blind study.

OBJECTIVES: Sexually transmitted infections (STIs) have markedly increased over the last decade in Spain, calling for prevention and control innovative approaches. While there is evidence indicating the effectiveness of self-sampling for STI diagnosis, no kits for this purpose have been authorised in Spain. METHODS: A prospective single-blind cross-sectional study carried out between November and December 2022 in an STI clinic in Madrid, Spain, to determine the validity, feasibility and acceptability of self-sampling kits used by non-healthcare professionals from vagina, pharynx, rectum and urethra to diagnose Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). Self-samples were compared with samples collected by healthcare professional (HC samples) and analysed by PCR. Frequency of CT and NG diagnosis by sample type was compared using McNemar's test for paired data. Sensitivity and specificity of self-samples for CT and NG diagnosis were also calculated. RESULTS: 306 self-samples from 51 participants were analysed. 80% were men with median age of 33 (IQR: 28-38) years. Self-samples and HC samples showed no significant statistical differences in CT and NG diagnosis. Self-samples had a sensitivity of 81% for CT and 93% for NG, with a specificity of 97% for CT and 95% for NG. More than 90% of participants had no difficulty understanding the kit instructions and 71% expressed high levels of satisfaction with the self-sampling kit. CONCLUSION: Self-sampling kits for CT and NG diagnosis can be safely and effectively used by non-healthcare professionals in Spain. National strategies for STI prevention and control should prioritise self-sampling strategies.

The Tropical Andes Biodiversity Hotspot: A Comprehensive Dataset for the Mira-Mataje Binational Basins.

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

Case report: Novel genotype of ALG2-CDG and confirmation of the heptasaccharide glycan (NeuAc-Gal-GlcNAc-Man2-GlcNAc2) as a specific diagnostic biomarker.

This report outlines the case of a child affected by a type of congenital disorder of glycosylation (CDG) known as ALG2-CDG (OMIM 607906), presenting as a congenital myasthenic syndrome (CMS) caused by variants identified in ALG2, which encodes an α1,3-mannosyltransferase (EC 2.4.1.132) involved in the early steps of N-glycosylation. To date, fourteen cases of ALG2-CDG have been documented worldwide. From birth, the child experienced perinatal asphyxia, muscular weakness, feeding difficulties linked to an absence of the sucking reflex, congenital hip dislocation, and hypotonia. Over time, additional complications emerged, such as inspiratory stridor, gastroesophageal reflux, low intake, recurrent seizures, respiratory infections, an inability to maintain the head upright, and a global developmental delay. Whole genome sequencing (WGS) revealed the presence of two ALG2 variants in compound heterozygosity: a novel variant c.1055_1056delinsTGA p.(Ser352Leufs*3) and a variant of uncertain significance (VUS) c.964C>A p.(Pro322Thr). Additional studies, including determination of carbohydrate-deficient transferrin (CDT) revealed a mild type I CDG pattern and the presence of an abnormal transferrin glycoform containing a linear heptasaccharide consisting of one sialic acid, one galactose, one N-acetyl-glucosamine, two mannoses and two N-acetylglucosamines (NeuAc-Gal-GlcNAc-Man2-GlcNAc2), ALG2-CDG diagnostic biomarker, confirming the pathogenicity of these variants.

Synergism between remdesivir and ribavirin leads to SARS-CoV-2 extinction in cell culture.

BACKGROUND AND PURPOSE: There is a need for effective anti-COVID-19 treatments, mainly for individuals at risk of severe disease such as the elderly and the immunosuppressed. Drug repositioning has proved effective in identifying drugs that can find a new application for the control of coronavirus disease, in particular COVID-19. The purpose of the present study was to find synergistic antiviral combinations for COVID-19 based on lethal mutagenesis. EXPERIMENTAL APPROACH: The effect of combinations of remdesivir and ribavirin on the infectivity of SARS-CoV-2 in cell culture has been tested. Viral populations were monitored by ultra-deep sequencing, and the decrease of infectivity as a result of the treatment was measured. KEY RESULTS: Remdesivir and ribavirin exerted a synergistic inhibitory activity against SARS-CoV-2, quantified both by CompuSyn (Chou-Talalay method) and Synergy Finder (ZIP-score model). In serial passage experiments, virus extinction was readily achieved with remdesivir-ribavirin combinations at concentrations well below their cytotoxic 50 value, but not with the drugs used individually. Deep sequencing of treated viral populations showed that remdesivir, ribavirin, and their combinations evoked significant increases of the number of viral mutations and haplotypes, as well as modification of diversity indices that characterize viral quasi-species. CONCLUSION AND IMPLICATIONS: SARS-CoV-2 extinction can be achieved by synergistic combination treatments based on lethal mutagenesis. In addition, the results offer prospects of triple drug treatments for effective SARS-CoV-2 suppression.

SARS-CoV-2 mutant spectra as variant of concern nurseries: endless variation?

Introduction: SARS-CoV-2 isolates of a given clade may contain low frequency genomes that encode amino acids or deletions which are typical of a different clade. Methods: Here we use high resolution ultra-deep sequencing to analyze SARS-CoV-2 mutant spectra. Results: In 6 out of 11 SARS-CoV-2 isolates from COVID-19 patients, the mutant spectrum of the spike (S)-coding region included two or more amino acids or deletions, that correspond to discordant viral clades. A similar observation is reported for laboratory populations of SARS-CoV-2 USA-WA1/2020, following a cell culture infection in the presence of remdesivir, ribavirin or their combinations. Moreover, some of the clade-discordant genome residues are found in the same haplotype within an amplicon. Discussion: We evaluate possible interpretations of these findings, and reviewed precedents for rapid selection of genomes with multiple mutations in RNA viruses. These considerations suggest that intra-host evolution may be sufficient to generate minority sequences which are closely related to sequences typical of other clades. The results provide a model for the origin of variants of concern during epidemic spread─in particular Omicron lineages─that does not require prolonged infection, involvement of immunocompromised individuals, or participation of intermediate, non-human hosts.

The effects of the industrial transition on lower limb bone structure: A comparison of the inhabitants of Pecos Pueblo and present-day Indigenous peoples of New Mexico.

OBJECTIVES: Comparisons between Indigenous peoples over time and within a particular geographic region can shed light on the impact of environmental transitions on the skeleton, including relative bone strength, sexual dimorphism, and age-related changes. Here we compare long bone structural properties of the inhabitants of the late prehistoric-early historic Pecos Pueblo with those of present-day Indigenous individuals from New Mexico. MATERIALS AND METHODS: Femora and tibiae of 126 adults from Pecos Pueblo and 226 present-day adults were included in the study. Cross-sectional diaphyseal properties-areas and second moments of area-were obtained from past studies of the Pecos Pueblo skeletal sample, and from computed tomography scans of recently deceased individuals in the present-day sample. RESULTS: Femora and tibiae from Pecos individuals are stronger relative to body size than those of present-day Indigenous individuals. Present-day individuals are taller but not wider, and this body shape difference affects cross-sectional shape, more strongly proximally. The tibia shows anteroposterior strengthening among Pecos individuals, especially among males. Sexual dimorphism in midshaft bone shape is stronger within the Pecos Pueblo sample. With aging, Pecos individuals show more medullary expansion but also more subperiosteal expansion than present-day individuals, maintaining bone strength despite cortical thinning. DISCUSSION: Higher activity levels, carried out over rough terrain and throughout adult life, likely explain the relatively stronger lower limb bones of the Pecos individuals, as well as their greater subperiosteal expansion with aging. Greater sexual dimorphism in bone structure among Pecos individuals potentially reflects greater gender-based differences in behavioral patterns.

Hydroalcoholic extract from Sechium edule (Jacq.) S.w. root reverses oleic acid-induced steatosis and insulin resistance in vitro.

Steatosis is characterized by fat accumulation and insulin resistance (IR) in hepatocytes, which triggers a pro-oxidant, pro-inflammatory environment that may eventually lead to cirrhosis or liver carcinoma. This work was aimed to assess the effect of Sechium edule root hydroalcoholic extract (rSe-HA) (rich in cinnamic and coumaric acid, among other phenolic compounds) on triglyceride esterification, lipid degradation, AMPK expression, and the phosphorylation of insulin receptor in a Ser312 residue, as well as on the redox status, malondialdehyde (MDA) production, and the production of proinflammatory cytokines in an in vitro model of steatosis induced by oleic acid, to help develop a phytomedicine that could reverse this pathology. rSe-HA reduced triglyceride levels in hepatocyte lysates, increased lipolysis by activating AMPK at Thr172, and improved the redox status, as evidenced by the concentration of glycerol and formazan, respectively. It also prevented insulin resistance (IR), as measured by glucose consumption and the phosphorylation of the insulin receptor at Ser312. It also prevented TNFα and IL6 production and decreased the levels of MDA and nitric oxide (ON). Our results indicate that rSe-HA reversed steatosis and controlled the proinflammatory and prooxidant environment in oleic acid-induced dysfunctional HepG2 hepatocytes, supporting its potential use to control this disorder.

Investigating vulnerability of the conserved SARS-CoV-2 spike's heptad repeat 2 as target for fusion inhibitors using chimeric miniproteins.

Inhibition of SARS-CoV-2 membrane fusion is a highly desired target to combat COVID-19. The interaction between the spike's heptad repeat (HR) regions 1 (HR1) and 2 (HR2) is a crucial step during the fusion process and these highly conserved HR regions constitute attractive targets for fusion inhibitors. However, the relative importance of each subregion of the long HR1-HR2 interface for viral inhibition remains unclear. Here, we designed, produced, and characterized a series of chimeric miniproteins that mimic two different half subdomains of HR1. The proteins were designed as single polypeptide chains that spontaneously fold into antiparallel trimeric helical bundles aimed at structurally imitate the molecular surface of each HR1 half subregion. All the miniproteins folded stably as helical structures and could bind complementary HR2 peptides with moderate affinity. However, only the miniproteins mimicking the N-terminal HR1 half subdomain, but not those imitating C-terminal one, could inhibit cell infection by SARS-COV-2 real viruses in cell cultures. Most interestingly, the inhibitory activity of the miniproteins correlated with their structural stability, but not with their relative binding affinity for HR2 peptides. These results are highly relevant for designing more focused and active fusion inhibitors targeting the highly conserved HR2 region of the Spike.

Selective Formation of Pd-DNA Hybrids Using Tailored Palladium-Mediated Base Pairs: Towards Heteroleptic Pd-DNA Systems.

The formation of highly organized metal-DNA structures has significant implications in bioinorganic chemistry, molecular biology and material science due to their unique properties and potential applications. In this study, we report on the conversion of single-stranded polydeoxycytidine (dC15 ) into a Pd-DNA supramolecular structure using the [Pd(Aqa)] complex (Aqa=8-amino-4-hydroxyquinoline-2-carboxylic acid) through a self-assembly process. The resulting Pd-DNA assembly closely resembles a natural double helix, with continuous [Pd(Aqa)(C)] (C=cytosine) units serving as palladium-mediated base pairs, forming interbase hydrogen bonds and intrastrand stacking interactions. Notably, the design of the [Pd(Aqa)] complex favours the interaction with cytosine, distinguishing it from our previously reported [Pd(Cheld)] complex (Cheld=chelidamic acid). This finding opens possibilities for creating heteroleptic Pd-DNA hybrids where different complexes specifically bind to nucleobases. We confirmed the Pd-DNA supramolecular structural assembly and selective binding of the complexes using NMR spectroscopy, circular dichroism, mass spectrometry, isothermal titration calorimetry, and DFT calculations.

Using High-Resolution Anoscopy to Detect Anal Dysplasia Due to Papillomavirus in Patients with Inflammatory Bowel Disease

Introduction: Anal squamous cell carcinoma is rare, but its incidence and mortality have been increasing globally; 90% of cases are related to human papillomavirus (HPV) infection(1,2). Patients with inflammatory bowel disease (IBD) have a higher risk of infection with this virus; an incidence of 5.5 per 100,000 patients has been identified in the IBD group compared to 1.8 in the non-IBD group(3). Materials and methods: A descriptive case series study was conducted with 21 patients with IBD and no perianal symptoms between January and July 2022 at the Institute of Coloproctology in Medellín. They underwent anal cytology, HPV genotyping, and high-resolution anoscopy after explanation and acceptance of the procedure. If lesions were found, ablative treatment was performed. Results: 23% of this cohort had low-grade squamous lesions, while 14.2% had high-grade lesions with dysplasia changes during anoscopy. Besides, 90.4% had positive HPV genotyping, of which 76.1% were high-grade. Conclusions: Our study suggests that this series of patients with IBD behaves as a high-risk group for developing premalignant lesions in association with HPV. High-resolution anoscopy is a cost-effective, painless, and affordable method that, in expert hands, may impact the diagnosis and management of premalignant lesions and decrease the incidence of anal cancer in patients with IBD.

Introducción: El carcinoma anal de células escamosas es raro, pero su incidencia y mortalidad han ido en aumento globalmente. El 90% de los casos están relacionados con la infección por el virus del papiloma humano (VPH)1,2 y los pacientes con enfermedad inflamatoria intestinal (EII) tienen un mayor riesgo de infección por este virus; se ha identificado una incidencia de 5,5 por 100.000 pacientes en el grupo de EII frente a 1,8 en el grupo sin EII3. Metodología: Se realizó un estudio descriptivo de serie de casos en el que se incluyó a 21 pacientes con EII, sin síntomas perianales, entre enero y julio de 2022 en el Instituto de Coloproctología de Medellín, a quienes se les realizó citología anal, genotipificación del VPH y anoscopia de alta resolución, previa explicación y aceptación del procedimiento. Si se encontraban lesiones, se realizaba tratamiento ablativo. Resultados: El 23% de esta cohorte tenía lesiones escamosas de bajo grado, mientras que el 14,2% presentaba lesiones de alto grado con cambios de displasia al momento de la anoscopia. El 90,4% tenían genotipificación positiva para VPH, de los cuales el 76,1% eran de alto grado. Conclusiones: Nuestro estudio sugiere que esta serie de pacientes con EII se comporta como un grupo de alto riesgo para desarrollar lesiones premalignas en asociación con el VPH. La anoscopia de alta resolución es un método rentable, indoloro y asequible que, en manos expertas, puede impactar el diagnóstico y manejo de lesiones premalignas y disminuir la incidencia de cáncer anal en pacientes con EII.

Aqueous Fraction from Cucumis sativus Aerial Parts Attenuates Angiotensin II-Induced Endothelial Dysfunction In Vivo by Activating Akt.

BACKGROUND: Endothelial dysfunction (ED) is a marker of vascular damage and a precursor of cardiovascular diseases such as hypertension, which involve inflammation and organ damage. Nitric oxide (NO), produced by eNOS, which is induced by pAKT, plays a crucial role in the function of a healthy endothelium. METHODS: A combination of subfractions SF1 and SF3 (C4) of the aqueous fraction from Cucumis sativus (Cs-Aq) was evaluated to control endothelial dysfunction in vivo and on HMEC-1 cells to assess the involvement of pAkt in vitro. C57BL/6J mice were injected daily with angiotensin II (Ang-II) for 10 weeks. Once hypertension was established, either Cs-AqC4 or losartan was orally administered along with Ang-II for a further 10 weeks. Blood pressure (BP) was measured at weeks 0, 5, 10, 15, and 20. In addition, serum creatinine, inflammatory status (in the kidney), tissue damage, and vascular remodeling (in the liver and aorta) were evaluated. Cs-AqC4 was also tested in vitro on HMEC-1 cells stimulated by Ang-II to assess the involvement of Akt phosphorylation. RESULTS: Cs-AqC4 decreased systolic and diastolic BP, reversed vascular remodeling, decreased IL-1ß and TGF-ß, increased IL-10, and decreased kidney and liver damage. In HMEC-1 cells, AKT phosphorylation and NO production were increased. CONCLUSIONS: Cs-AqC4 controlled inflammation and vascular remodeling, alleviating hypertension; it also improved tissue damage associated with ED, probably via Akt activation.

Effects of the energy balance transition on bone mass and strength.

Chronic positive energy balance has surged among societies worldwide due to increasing dietary energy intake and decreasing physical activity, a phenomenon called the energy balance transition. Here, we investigate the effects of this transition on bone mass and strength. We focus on the Indigenous peoples of New Mexico in the United States, a rare case of a group for which data can be compared between individuals living before and after the start of the transition. We show that since the transition began, bone strength in the leg has markedly decreased, even though bone mass has apparently increased. Decreased bone strength, coupled with a high prevalence of obesity, has resulted in many people today having weaker bones that must sustain excessively heavy loads, potentially heightening their risk of a bone fracture. These findings may provide insight into more widespread upward trends in bone fragility and fracture risk among societies undergoing the energy balance transition.

Effects of Supplementation with the Standardized Extract of Saffron (affron®) on the Kynurenine Pathway and Melatonin Synthesis in Rats.

Melatonin is a hormone that regulates sleep-wake cycles and is mainly synthesized in the pineal gland from tryptophan after its conversion into serotonin. Under normal conditions, less than 5% of tryptophan is reserved for the synthesis of serotonin and melatonin. The remaining 95% is metabolized in the liver through the kynurenine pathway. Increased levels of proinflammatory cytokines and cortisol increase the metabolism of tryptophan through the kynurenine pathway and reduce its availability for the synthesis of melatonin and serotonin, which may cause alterations in mood and sleep. The standardized saffron extract (affron®) has shown beneficial effects on mood and sleep disorders in humans, but the underlying mechanisms are not well understood. Thus, the aim of this work was to study the effects of affron® supplementation on the kynurenine pathway and the synthesis of melatonin in rats. For this purpose, adult male Wistar rats were supplemented for 7 days with 150 mg/kg of affron® or vehicle (2 mL/kg water) administered by gavage one hour before sleep. Affron® supplementation reduced body weight gain and increased the circulating levels of melatonin, testosterone, and c-HDL. Moreover, animals supplemented with affron® showed decreased serum levels of kynurenine, ET-1, and c-LDL. In the pineal gland, affron® reduced Il-6 expression and increased the expression of Aanat, the key enzyme for melatonin synthesis. In the liver, affron® administration decreased the mRNA levels of the enzymes of the kynurenine pathway Ido-2, Tod-2, and Aadat, as well as the gene expression of Il-1ß and Tnf-α. Finally, rats treated with affron® showed increased mRNA levels of the antioxidant enzymes Ho-1, Sod-1, Gsr, and Gpx-3, both in the liver and in the pineal gland. In conclusion, affron® supplementation reduces kynurenine levels and promotes melatonin synthesis in rats, possibly through its antioxidant and anti-inflammatory effects, making this extract a possible alternative for the treatment and/or prevention of mood and sleep disorders.

Supplementation with a New Standardized Extract of Green and Black Tea Exerts Antiadipogenic Effects and Prevents Insulin Resistance in Mice with Metabolic Syndrome.

Insulin resistance is one of the main characteristics of metabolic syndrome (MetS) and the main cause of the development of type II diabetes. The high prevalence of this syndrome in recent decades has made it necessary to search for preventive and therapeutic agents, ideally of natural origin, with fewer side effects than conventional pharmacological treatments. Tea is widely known for its medicinal properties, including beneficial effects on weight management and insulin resistance. The aim of this study was to analyze whether a standardized extract of green and black tea (ADM® Complex Tea Extract (CTE)) prevents the development of insulin resistance in mice with MetS. For this purpose, C57BL6/J mice were fed for 20 weeks with a standard diet (Chow), a diet with 56% kcal from fat and sugar (HFHS) or an HFHS diet supplemented with 1.6% CTE. CTE supplementation reduced body weight gain, adiposity and circulating leptin levels. Likewise, CTE also exerted lipolytic and antiadipogenic effects in 3T3-L1 adipocyte cultures and in the C. elegans model. Regarding insulin resistance, CTE supplementation significantly increased plasma adiponectin concentrations and reduced the circulating levels of insulin and the HOMA-IR. Incubation of liver, gastrocnemius muscle and retroperitoneal adipose tissue explants with insulin increased the pAkt/Akt ratio in mice fed with Chow and HFHS + CTE but not in those fed only with HFHS. The greater activation of the PI3K/Akt pathway in response to insulin in mice supplemented with CTE was associated with a decrease in the expression of the proinflammatory markers Mcp-1, IL-6, IL-1ß or Tnf-α and with an overexpression of the antioxidant enzymes Sod-1, Gpx-3, Ho-1 and Gsr in these tissues. Moreover, in skeletal muscle, mice treated with CTE showed increased mRNA levels of the aryl hydrocarbon receptor (Ahr), Arnt and Nrf2, suggesting that the CTE's insulin-sensitizing effects could be the result of the activation of this pathway. In conclusion, supplementation with the standardized extract of green and black tea CTE reduces body weight gain, exerts lipolytic and antiadipogenic effects and reduces insulin resistance in mice with MetS through its anti-inflammatory and antioxidant effects.

Two new syntopic species of glassfrogs (Amphibia, Centrolenidae, Centrolene) from the southwestern Andes of Ecuador.

We describe two new species of glassfrogs of the genus Centrolene living in syntopy at La Enramada, province of Azuay, southwestern Ecuador. They were found in a small creek in montane evergreen forests at 2,900 m elevation. The first new species is distinguished from all other members of the genus Centrolene by having the following combination of characters: dentigerous process of vomer absent; sloping snout in lateral view; thick, white labial stripe and a faint white line between the lip and anterior » of body; humeral spine in adult males; parietal peritoneum covered by iridophores, visceral peritonea translucent (except pericardium); ulnar and tarsal ornamentation; dorsal skin shagreen with dispersed warts; uniform green dorsum with light yellowish green warts; and green bones. The new species is remarkable by being sister to a species from the opposite Andean versant, C. condor. The second new species is distinguished from all other Centrolene by having the following combination of characters: dentigerous process of vomer absent; round snout in lateral view; thin, yellowish labial stripe with a row of white tubercles between the lip and arm insertion, and a yellowish line between arm insertion and groin; uniform green dorsum; humeral spine in adult males; parietal peritoneum covered by iridophores, visceral peritonea translucent (except pericardium); dorsal skin shagreen with dispersed spicules; ulnar and tarsal ornamentation; and green bones. The second new species is sister to C. sabini and an undescribed species of Centrolene from southeastern Ecuador. Based on nuclear and mitochondrial DNA sequences, we present a new phylogeny for Centrolene and comment on the phylogenetic relationships inside the genus.

Unveiling the evolutionary relationships and the high cryptic diversity in Andean rainfrogs (Craugastoridae: Pristimantis myersi group).

Background: Pristimantis is the most diverse genus of terrestrial frogs. Historically, it has been divided into several phenetic groups in order to facilitate species identification. However, in light of phylogenetic analysis, many of these groups have been shown to be non-monophyletic, denoting a high degree of morphological convergence and limited number of diagnostic traits. In this study, we focus on the Pristimantis myersi group, an assemblage of small rainfrogs distributed throughout the Andes of Ecuador and Colombia, whose external morphology is highly conserved, and its species diversity and evolutionary relationships largely unknown. Methods: We inferred a new phylogenetic hypothesis for the frog genus Pristimantis, including all available sequences of the mtDNA 16S rRNA, as well as new DNA sequences from 175 specimens. Our sampling included 19 of the 24 species currently recognized as part of the Pristimantis myersi group. Results: Our new evolutionary hypothesis recovered the P. myersi group as non-monophyletic and composed of 16 species. Therefore, we exclude P. albujai, P. bicantus, P. sambalan, and P. nelsongalloi in order to preserve the monophyly of the group. We discovered at least eight candidate species, most of them hidden under the names of P. leoni, P. hectus, P. festae, P. gladiator, and P. ocreatus. Discussion: Our results reveal the occurrence of a high level of cryptic diversity to the species level within the P. myersi group and highlight the need to redefine some of its species and reassess their conservation status. We suggest that the conservation status of six species within the group need to be re-evaluated because they exhibit smaller distributions than previously thought; these species are: P. festae, P. gladiator, P. hectus, P. leoni, P. ocreatus, and P. pyrrhomerus. Finally, given that the Pristimantis myersi group, as defined in this work, is monophyletic and morphologically diagnosable, and that Trachyphrynus is an available name for the clade containing P. myersi, we implement Trachyphrynus as a formal subgenus name for the Pristimantis myersi group.