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Open Access
2b-RAD genotyping for population genomic studies of Chagas disease vectors: Rhodnius ecuadoriensis in Ecuador
(2017) Costales Cordero, Jaime Alfredo; Ocaña Mayorga, Sofía Beatriz; Villacis Salazar, Anita Gabriela; Yumiseva Marín, César Alberto; Jaime Alfredo Costales Cordero, Sofía Beatriz Ocaña Mayorga, Anita Gabriela Villacis Salazar y César Alberto Yumiseva Marín
Rhodnius ecuadoriensis is the main triatomine vector of Chagas disease, American trypanosomiasis, in Southern Ecuador and Northern Peru. Genomic approaches and next generation sequencing technologies have become powerful tools for investigating population diversity and structure which is a key consideration for vector control. Here we assess the effectiveness of three different 2b restriction site-associated DNA (2b-RAD) genotyping strategies in R. ecuadoriensis to provide sufficient genomic resolution to tease apart microevolutionary processes and undertake some pilot population genomic analyses.
Open Access
4(1H)-Quinolones with liver stage activity against Plasmodium berghei.
(2013) Sáenz Calderón, Fabián Ernesto; LaCrue, Alexis N.
With the exception of primaquine, tafenoquine, and atovaquone, there are very few antimalarials that target liver stage parasites. In this study, a transgenic Plasmodium berghei parasite (1052Cl1; PbGFP-Luccon) that expresses luciferase was used to assess the anti-liver stage parasite activity of ICI 56,780, a 7-(2-phenoxyethoxy)-4(1H)-quinolone (PEQ), as well as two 3-phenyl-4(1H)-quinolones (P4Q), P4Q-146 and P4Q-158, by using bioluminescent imaging (BLI). Results showed that all of the compounds were active against liver stage parasites; however, ICI 56,780 and P4Q-158 were the most active, with low nanomolar activity in vitro and causal prophylactic activity in vivo. This potent activity makes these compounds ideal candidates for advancement as novel antimalarials.
Open Access
4-(1H)-Quinolones and 1,2,3,4-tetrahydroacridin-9(10H)-ones prevent the transmission of Plasmodium falciparum to Anopheles freeborni.
(2013) Sáenz Calderón, Fabián Ernesto; Sáenz Calderón, Fabián Ernesto
Malaria kills approximately 1 million people a year, mainly in sub-Saharan Africa. Essential steps in the life cycle of the parasite are the development of gametocytes, as well as the formation of oocysts and sporozoites, in the Anopheles mosquito vector. Preventing transmission of malaria through the mosquito is necessary for the control of the disease; nevertheless, the vast majority of drugs in use act primarily against the blood stages. The study described herein focuses on the assessment of the transmissionblocking activities of potent antierythrocytic stage agents derived from the 4(1H)-quinolone scaffold. In particular, three 3-alkylor 3-phenyl-4(1H)-quinolones (P4Qs), one 7-(2-phenoxyethoxy)-4(1H)-quinolone (PEQ), and one 1,2,3,4-tetrahydroacridin- 9(10H)-one (THA) were assessed for their transmission-blocking activity against the mosquito stages of the human malaria parasite (Plasmodium falciparum) and the rodent parasite (P. berghei). Results showed that all of the experimental compounds reduced or prevented the exflagellation of male gametocytes and, more importantly, prevented parasite transmission to the mosquito vector. Additionally, treatment with ICI 56,780 reduced the number of sporozoites that reached the Anopheles salivary glands. These findings suggest that 4(1H)-quinolones, which have activity against the blood stages, can also prevent the transmission of Plasmodium to the mosquito and, hence, are potentially important drug candidates to eradicate malaria.
Open Access
A bizarre new species of Lynchius (Amphibia, Anura, Strabomantidae) from the Andes of Ecuador and first report of Lynchius parkeri in Ecuador
(2019) Ron Melo, Santiago Rafael; Ron Melo, Santiago Rafael
We describe a new species of Lynchius from the eastern montane forest of southern Ecuador. We also report the occurrence of L. parkeri in Ecuador, on paramos of Yacuri National Park, near the border with Peru. We used morphological and genetic evidence for the description of the new species and the new report of L. parkeri. Phylogenetic analyses were carried out using both maximum likelihood and Bayesian inference on DNA sequences for mitochondrial and nuclear genes. The phylogeny shows that L. simmonsi is sister to a clade composed of the remaining species of Lynchius and that the new species is sister to L. flavomaculatus. The new species has a prominent and heavily ossified head with noticeably spiculate cranial exostosis that easily distinguishes it from all its congeners. The dorsal region and limbs present several reduced subconical and rounded tubercles and pronounced dermal ridges on the dorsum. We also describe the osteology of the new species based on x-rays of the holotype. Only six species of Lynchius, two known to occur in Ecuador (L. flavomaculatus and L. simmonsi). The description of L. megacephalus sp. n. and new record of L. parkeri double the number of known Lynchius in Ecuador and suggest that the diversity of Ecuadorian and Peruvian Lynchius is still underestimated.
Open Access
A Common but Overlooked New Species in the Hyper-Diverse Genus Inga Mill. from the Northwestern Amazon
(2019) Hernández Rentería, Consuelo Bethsabé; Valencia Reyes, Luis Renato; Hernández Rentería, Consuelo Bethsabé y Valencia Reyes, Luis Renato
Inga kursarii is a new species collected in the terra firme forests of the northwestern Amazon, one of the regions with the highest tree species diversity in the world. According to morphological and phylogenetic analyses, the new species is morphologically similar and sister to Inga gracilifolia Ducke, but it can be distinguished by having 5–6 pairs of caducous leaflets, elliptical leaflets with acute apex and slightly asymmetrical base, spiked inflorescence, subsessile flowers, calyx tube with 4 lobes, tufts of hairs at the apex of calyx lobes, corolla tube with non reflexed lobes, shorter staminal tubes, and capitate stigma. In addition, analyses of the chemical defensive profile (chemocoding) show that both taxa are chemically different, with I. kursarii having a chemistry based on gallocatechin/epigallocatechin gallates, and I. gracilifolia producing a series of dihydroflavonols. Finally, we present a table with a comparison of diagnostic characters that allows separation of the two species.
Open Access
A comparative analysis reveals weak relationships between ecological factors and beta diversity of stream insect metacommunities at two spatial levels
(2015-02-23) Dangles, Olivier Jacques; Dangles, Olivier Jacques
The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilarity-based indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity, we used a combination of spatial eigenfunction analyses and partial redundancy analysis to partition variation in assemblage structure into environmental, shared, spatial, and unexplained fractions. We found that dataset properties were more important predictors of beta diversity than ecological and geographical factors across multiple drainage basins. In the within-basin analyses, environmental and spatial variables were generally poor predictors of variation in assemblage composition. Our results revealed deviation from general biodiversity patterns because beta diversity did not show the expected decreasing trend with latitude. Our results also call for reconsideration of just how predictable stream assemblages are along ecological gradients, with implications for environmental assessment and conservation decisions. Our findings may also be applicable to other dynamic systems where predictability is low.
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A computational study of steviol and its suggested anticancer activity. A DFT and docking study
(2021-09) Meneses Olmedo, Lorena Maribel; Meneses Olmedo, Lorena Maribel
In the present, study we analyzed the electronic properties of Steviol, the Stevia rebaudiana metabolite, and its interaction with antiapoptotic protein BCL-2. The ionization potential and electrophilicity index values were evaluated in the framework of the DFT, and these values suggest that Steviol may form ligand-receptor interactions. Also, the bond dissociation energy and the electrostatic potential distribution of Steviol reveal its antioxidant behavior. Docking studies were performed to evaluate the feasibility of this molecule to interact with antiapoptotic protein BCL-2. However, no hydrogen bonds were found in the pocket site, instead six interactions, including alkyl and π-alkyl type were formed, suggesting that the possible most feasible mechanism for anticancer activity would be through free radicals scavenging.
Open Access
A manual suction toilet for sewage reduction
(2020) Basantes Flores, Andrés Esteban; Davis Michael, Joseph Maks; Sáez Vaquero, José María; Basantes Flores, Andrés Esteban, Davis Michael, Joseph Maks y Sáez Vaquero, José María
In Ecuador, 46.4% of households lack access to a sewerage system, where as a result much wastewater is discharged from sewerage into the environment untreated. This paper presents the results of a research project aimed at the development of prototypes that retrofit existing toilets into a manual suction ultra-low flush toilet. These prototypes use around one liter of water, and therefore the amount of sewage produced is substantially reduced. The strategy covered two areas. First, the prototype design is developed with the active participation from users using sociological study tools such as workshops, focus groups and interviews, which enabled to polish or re-define design aspects aimed at improving levels of end-user acceptance. Second, dissemination of results and designed products is implemented through web platforms to enable replicability, allowing potential participation from external collaborators. The main approach of this research is to act at a small scale (houses, departments, buildings) in order to amend the amount of metric tons of wastewater within a larger urban scale.
Open Access
A multi-causal model for chronic malnutrition and anemia in a population of rural coastal children
(2019-12-14) Astudillo Silva, Ricardo Fabricio; Buitrón Sánchez, Gladys Janett; Moncayo Benalcázar, Ana Lucía; Rivadeneira Guerrero, María Fernanda; Tello Ponce, Betzabé Magdalena; Astudillo Silva, R., Buitrón Sánchez, G., Moncayo Benalcázar, A., Rivadeneira Guerrero, M. y Tello Ponce, B.
Objectives: Chronic malnutrition and anemia are prevalent in developing countries. This research aimed to determine the prevalence of chronic malnutrition and anemia and their associated factors in children under five using a multi-causal model in a rural community in the coast of Ecuador. Methods: The study included 314 children under 5 years old who were residents of San Isidro, Ecuador. Indicators of chronic malnutrition and anemia were identified. Mothers/caregivers were surveyed on socio-economic and environmental conditions, feeding and care practices, access to health services and biological characteristics. Bivariate and multivariable Poisson regression were performed. Results: The prevalence was 12.42% (n = 39) for chronic malnutrition and 16.98% (n = 54) for anemia. There was a significant and independent association between chronic malnutrition and family income less than $80 USD per month (Prevalence Ratio [PR] = 2.74, 95% CI 1.04, 7.20), maternal height less than 150 cm (PR 3.00, 95% CI 1.69, 5.32) and residence in a household with more than 4 children (PR 3.05, 95% CI 1.48, 6.29). Anemia was 2.57 times higher (95% CI 1.17, 5.65) in children with more than two episodes of diarrhea in the last 6 months. Prenatal care (5 to 8 visits) provided a protective effect for anemia (PR 0.48, 95% CI 0.27, 0.89). Conclusions for Practice: Findings support the need for comprehensive interventions targeted toward chronic malnutrition and anemia in children from rural coastal communities. Improvement of socioeconomic conditions, family planning, prenatal care and reduction of diarrheal diseases should be prioritized.
Open Access
A nafion film cover to enhance the analytical performance of the CuO/Cu electrochemical sensor for determination of chemical oxygen demand
(2019-02) Espinoza-Montero, Patricio Javier; Fernández Martínez, Lenys Mercedes; Espinoza-Montero, Patricio Javier y Fernández Martínez, Lenys Mercedes
We modiﬁed and evaluated the performance of a CuO/Cu electrochemical electrode for chemical oxygen demand (COD) determination by covering it with a Naﬁon (Nf) ﬁlm. The resulting modiﬁed CuONf/Cu electrode sensor was used for the electrochemical determination of COD in river, slaughterhouse and estuarine water samples in order to evaluate its performance for this particular task. It was compared with the CuO/Cu sensor with no Naﬁon. The main electrochemical characteristics of interest, resistance, sensitivity, accuracy and reproducibility, were assessed by means of Linear Sweep Voltammetry using glucose as a standard. Results of these essays indicate that the procedure used produced smooth and ﬁrmly attached Nf ﬁlms covering the whole copper surface. This sensor was shown to be resistant to interferences and effective in electro-oxidation of a wide range of organic compounds and therefore very useful for COD determination. Using the newly developed CuONf/Cu electrode an analytical linear range of 50 to 1000 mg·L−1 COD, with a detectionlimitof2.11mg·L−1 (n=6)CODwasachieved. The comparison shows that theCuONf/Cu sensor is more appropriate for COD determination than its counterpart with no Naﬁon.
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A new case of interoceanic movement of a humpback whale in the southern hemisphere: The El Niño Link
(2020) Félix Grijalva, Fernando; Félix Grijalva, Fernando
Extensive seasonal migrations by humpback whales (Megaptera novaeangliae) have been well documented for decades. Unlike other more oceanic whales with complex seasonal patterns, such as blue (Balaenoptera musculus), sei (B. borealis), and even Bryde's (B. edeni) whales the presence of humpback whales in destination areas in high and low latitudes are predominantly regular and predictable. Based on their breeding areas, the International Whaling Commission (IWC) recognizes seven different stocks of humpback whales in the Southern Hemisphere, assigned as Breeding Stocks A to G. Genetic studies largely support this separation, although a certain level of gene flow between the different stocks exists. Although long-term migratory fidelity between breeding and feeding sites is well known in humpback whales, some individuals deviate from this pattern. This has been related to large-scale ocean-atmospheric events, changes in prey distribution, and probably other lesser-known ecological processes driven by climate change. Here, a new case of the interoceanic movement of a humpback whale recorded during the breeding season in two different ocean basins is presented.
Open Access
A new cryptic species of Anolis lizard from northwestern South America (Iguanidae, Dactyloinae)
(2018-11) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin Omar
A new species of Anolis lizard from the Andean slopes of southwestern Colombia and northwestern Ecuador, from between 1187 and 2353 m in elevation, is described. The new species can be distinguished from other Anolis in squamation, cranial osteology, hemipenial morphology, and nuclear and mitochondrial DNA. The new species is sister to Anolis aequatorialis, and it is suggested that previous records of A. aequatorialis in Colombia correspond to the new species described herein.
Open Access
A new cryptic species of the Pristimantis lacrimosus group (Anura, Strabomantidae) from the eastern slopes of the Ecuadorian Andes
(2021-07-23) Carrión Olmedo, Julio Cësar; Ron Melo, Santiago Rafael; Carrión Olmedo, Julio César y Ron Melo, Santiago Rafael
With 566 species, the neotropical genus Pristimantis is the most speciose vertebrate genus. As a result of its striking diversity, taxonomic reviews remain a challenge. Herein, we present an updated phylogeny of the Pristimantis lacrimosus group and describe a new species from Llanganates and Sangay National Parks. We also report, for the first time, the phylogenetic position of Pristimantis degener, P. eugeniae, P. katoptroides, and P. petersi. Based on our phylogeny, we add two species to the Pristimantis lacrimosus group. Through the integration of molecular and bioacoustic evidence, we describe a new species which was hidden under “Pristimantis petersi”. Pristimantis petersioides sp. nov. is most closely related to Pristimantis petersi and an undescribed species from Peru. It can be distinguished from P. petersi by its advertisement call and large genetic differences (uncorrected p-genetic distances 7.9% to 8.4% for gene 16S). Moreover, the new species and P. petersi are not sister species. We suggest assigning the new species to the Endangered Red List category because it has a small distribution range with deforestation as result of agriculture and other anthropogenic influences.
Open Access
A new giant anole (Squamata: Iguanidae: Dactyloinae) from southwestern Ecuador
(2021) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin Omar
We describe a new species of Anolis lizard from the Pacific slopes of the Andes of southwestern Ecuador at elevations between 372–1,000 m. The new species belongs to the Dactyloa clade and may be distinguished from other Anolis by size, external anatomy, mitochondrial DNA divergence, and dewlap color. Based on phylogenetic analyses of mitochondrial and nuclear DNA sequence data, we found that the new species is sister to A. fraseri in a clade composed primarily of large Dactyloid species. The new species is known from a protected area in southern Ecuador, Buenaventura Reserve, which suggests that at least some its populations are well protected.
Open Access
A new morphological cell parameter based on optical phase for the evaluation of cell populations
(2018-08-18) Gonzalez-Laprea, Jesus Ernesto; Gonzalez-Laprea,Jesus Ernesto
In this work, we introduce an opto-geometric parameter for the morphologic characterization of cell populations during their early adhesion process. Using measurements for a cell population of the maximal optical phase for each cell and its substrate-contact-surface, we show, experimentally, that a relationship exists between these variables. This connection is primarily associated with morphological cell characteristics. It is also shown that using the relationship obtained above, we can derive a morphological parameter, which, for the cell populations studied, results in a monodisperse Gaussiansize distribution, which would allow for the use of regular statistical variables. This result is in total contrast with the polydisperse distribution obtained if only the contact surface area between cell and substrate is used. In addition, optical phase measurements where accomplished by phase shifted interferometry using a Mirau-type interference microscope. The cellular system studied consisted of Osteoblast-like cells, plated on 316VM medical-grade stainless steel polished surfaces. These cell populations were studied within the same culture conditions of cell type, plating time and substrate roughness conditions. The existence of a relationship between maximal optical phase and substrate contact area agrees entirely with the accepted spreading model for cell adhesion; in particular, considering the close link between the optical phase time change and cell thickness reduction.
Open Access
A new polytypic species of yellow-shouldered bats, genus Sturnira (Mammalia: Chiroptera: Phyllostomidae), from the Andean and coastal mountain systems of Venezuela and Colombia
(2017-03-17) Burneo Nuñez, Santiago Fernando; Camacho Monge, María Alejandra; Burneo Nuñez, Santiago Fernando y Camacho Monge, María Alejandra
Sturnira is the most speciose genus of New World leaf-nosed bats (Phyllostomidae). We name Sturnira adrianae, new species. This taxon is born polytypic, divided into a larger subspecies (S. a. adrianae) widespread in the mountains of northern and western Venezuela, and northern Colombia, and a smaller subspecies (S. a. caripana) endemic to the mountains of northeastern Venezuela. The new species inhabits evergreen, deciduous, and cloud forests at mainly medium (1000–2000 m) elevations. It has long been confused with S. ludovici, but it is more closely related to S. oporaphilum. It can be distinguished from other species of Sturnira by genetic data, and based on discrete and continuously varying characters. Within the genus, the new species belongs to a clade that also includes S. oporaphilum, S. ludovici, S. hondurensis, and S. burtonlimi. The larger new subspecies is the largest member of this clade. The two new subspecies are the most sexually dimorphic members of this clade. The smaller new subspecies is restricted to small mountain systems undergoing severe deforestation processes, therefore can be assigned to the Vulnerable (VU) conservation category of the International Union for Conservation of Nature (IUCN).
Open Access
A new species of cat-eyed snake (Serpentes: Dipsadinae: Leptodeirini) from the Andes of southern Ecuador
(2020) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin Omar
Leptodeira is one of the most widespread and taxonomically problematic snake taxa in the Americas. Here we describe a new species of Leptodeira from the Andes of southern Ecuador based on morphological and molecular data. The new species is geographically close and morphologically similar to L. ornata and L. larcorum, from which it can be distinguished by having smaller dorsal body blotches, a longer tail, and shorter spines on the hemipenial body. The shortest genetic distances between the new species and its congeners are 0.02 (16S), 0.05 (cytb), and 0.18 (ND4). The new species is restricted to the Jubones River Basin in southern Ecuador, an area of endemism for other reptile species. Our phylogenetic analysis based on mitochondrial and nuclear DNA sequence data also supports recognition of the names L. larcorum (restricted to Peru) for “L. septentrionalis larcorum”, and L. ornata for populations of “L. s. ornata” from central and eastern Panama, western Colombia, and western Ecuador. However, some samples of “L. s. ornata” from Panama and Costa Rica, as well as the new species described herein, are not included within or more closely related to L. ornata, which is sister to the clade (L. bakeri, L. ashmeadii).
Open Access
A new species of dactyloid anole (Iguanidae, Polychrotinae, Anolis) from the southeastern slopes of the Andes of Ecuador
(2010) Torres Carvajal, Lenin Omar; Ayala-Varela, Fernando
We describe a new species of Anolis from the southeastern slopes of the Andes of Ecuador, province of Zamora-Chinchipe, Parque Nacional Podocarpus. It belongs to (1) the aequatorialis species-group by be- ing of moderate to large size with narrow toe lamellae, and (2) the eulaemus sub-group by having a typical Anolis digit, in which the distal lamellae of phalanx II distinctly overlap the proximal scales of phalanx I. The new species is most similar morphologically to A. fitchi but differs from it mainly by having a dewlap with longitudinal rows of 2−5 granular, minute scales separated by naked skin (longitudinal rows of one or two keeled, large scales separated by naked skin in A. fitchi) and a vertically shorter dewlap (longer dewlap in A. fitchi).
Open Access
A new species of direct-developing frog of the genus Pristimantis (Anura: Terrarana: Craugastoridae) from Cordillera del Cóndor, Ecuador, with comments on threats to the anuran fauna of the region
(2017) Ron Melo, Santiago Rafael; Ron Melo, Santiago Rafael
A new frog in the genus Pristimantis is described from a cloud forest on the western flanks of the Cordillera del Cóndor and eastern Andean slopes in the province of Zamora Chinchipe, southeastern of Ecuador. We inferred its phylogenetic position using DNA sequences of mitochondrial and nuclear genes. The new species is strongly supported as part of a clade that includes P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. chalceus, P. minutulus, P. luteolateralis, P. parvillus, P. ockendeni, P. unistrigatus, and P. walkeri. It can be distinguished from all other species from Cordillera del Cóndor and congeneric species by the unique combination of the following characters: (1) iris light blue with black reticulations; (2) skin of dorsum finely shagreen with scattered pustular tubercles and absence of dorsal folds; (3) tympanic membrane and tympanic annulus visible; (4) snout rounded in dorsal and lateral view; (5) upper eyelid bearing two or three enlarged subconical tubercles; (6) cranial crest absent; (7) males lacking vocal sac and slits; and (8) venter uniformly bright red, light red, salmon or orange. The new species is most closely related to P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. ockendeni and P. unistrigatus. We consider the new species to be Endangered following IUCN criteria because it has been severely affected by large scale open-pit mining in some localities. Currently, the amphibian fauna of the Cordillera del Cóndor and nearby protected areas are threatened by large–scale copper and gold mining projects with devastating effects on ~20 species, including several undescribed ones.
Open Access
A new species of Drosophila (Diptera: Drosophilidae) from the Inflorescences of Xanthosoma sagittifolium (Araceae)
(2017-05) Rafael Hidalgo, Violeta Lily; Rafael Hidalgo, Violeta Lily
A new species of the genus Drosophila, Drosophila sagittifolii sp. nov. is described. Adult specimens of D. sagittifolii were aspirated from the inflorescences of Xanthosoma sagittifolium (L.) Schott (camacho), from which they also emerged, at the Río Guajalito Research Station, Santo Domingo de los Tsáchilas, Ecuador.

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