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1.
Evolution ; 77(12): 2576-2589, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-37738625

RESUMO

Sexual dimorphism describes phenotypic differences between the sexes; the most prominent of which is sexual size dimorphism (SSD). Rensch's rule (RR) is an allometric trend in which SSD increases in male-larger taxa and decreases in female-larger ones. Covariation between a trait and overall size within and across species can both be affected by sexual and natural selection. Thus, intraspecific allometric variation could influence the expression of RR. Here we used computer simulations to dissect how RR emerges under specific allometric patterns of intraspecific sexual differentiation in a trait. We found that sexual differentiation in static allometric slopes is the main determinant of RR. Based on our findings, RR and its converse can manifest in both body size and other traits. As a realistic showcase, we also examined RR and static allometry of different body parts in Mediterranean green lizards to establish whether intraspecific and evolutionary allometry are linked. Here, we identified RR and its converse for different traits, where the amount of sexual differentiation in static allometric slopes within species had a significant contribution to RR. Integrating the simulations and the empirical case we corroborate that sexual differentiation in static allometric slopes is a major parameter affecting evolutionary allometry.


Assuntos
Evolução Biológica , Caracteres Sexuais , Masculino , Feminino , Humanos , Tamanho Corporal , Fenótipo , Seleção Genética
3.
Zookeys ; 1180: 257-293, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38312322

RESUMO

The explosive diversity of rainfrogs (Pristimantis spp) reaches its highest levels in the mountains of the Tropical Andes, with remarkable cryptic species mainly in unexplored areas of Ecuador. Based on phylogenetics, morphometric traits, skull osteology and bioacoustics, we describe two new species of Pristimantis, previously confused with Pristimantisgladiator, that belong to the subgenus Trachyphrynus traditionally known as the Pristimantismyersi species group. The two new taxa are closely related, but have allopatric distributions. We discuss the importance of the Quijos and Pastaza River valleys in the diversification along Amazonian slopes of the Ecuadorian Andes.

4.
Biodivers Data J ; 11: e98119, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327364

RESUMO

Habitat disturbance leads to biodiversity decline and modifications in the landscape structure and composition, affecting both dispersal movements and ecological processes at different temporal and spatial scales. The Ecuadorian Tropical Andes harbour suitable habitats for the distribution of a wide variety of species; however, there is a lack of studies focused on mammal diversity and its association with the habitat attributes in the central-eastern slopes. Here, we reported the diversity of terrestrial mammals recorded between 2019 and 2021 in a camera-trap monitoring study in the Candelaria and Machay reserves in the upper basin of the Pastaza River, Ecuador. We performed site-occupancy probability analysis to assess the influence of spatial variables in the species' occurrence and also, based on natural marks, we reported preliminary findings in Andean bear individual identification. We detected 22 species of terrestrial mammals. Alpha diversity was similar between reserves with slightly higher species richness in Machay. Evenness indices showed unequal species distribution, with the Andean bear and domestic dogs exhibiting greater dominance. In addition, species composition was dissimilar between reserves, where the species turnover mostly explained the beta diversity. We observed that Andean bear and puma detections increased according to the natural vegetation cover. Conversely, domestic dogs were frequently detected in cells with an increasing proportion of pastures and crops. Additionally, we identified 26 Andean bears and six individuals recaptured during our study. Our results caution about the disturbance derived from human activities since we recorded unprecedented detections of domestic dogs in wild habitats. Nonetheless, it highlights the importance of private conservation areas (e.g. Candelaria, Machay and others) for supporting the occurrence and dispersal of terrestrial mammal species between larger areas in the upper basin of the Pastaza River.

5.
Zookeys ; 1081: 35-87, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35087295

RESUMO

We present the results of herpetological surveys in two adjacent mountains where the EcoMinga Foundation protects the cloud forest in the Upper Rio Pastaza watershed, in the Llanganates Sangay Ecological Corridor in Ecuador. A rapid assessment of the amphibian communities of the study sites reveals a diverse and heterogeneous composition, dominated by terrestrial frogs from the genus Pristimantis. We also identify a cryptic diversity with a significant number of candidate new species. We describe two new species of terrestrial frogs of the genus Pristimantis. Pristimantismaryanneae sp. nov. is characterised by not having tympanum externally visible and having 2-3 subconical tubercles in the upper eyelid; and Pristimantisburtoniorum sp. nov. is characterised by the presence of red colouration in hidden surfaces of the hind-limbs, tubercles on the upper eyelid, interorbital tubercle and a row of rounded tubercles along the snout to the tip and a pale red venter with dark brown mottled pattern. Our samples from the two Reserves do not share species between them, so the proportion of shared species seems to be relatively low. In addition, we highlight the importance of updating the knowledge of amphibians that are restricted to this important conservation region and comment about the threats and composition of the amphibian communities on the eastern slopes of the Upper Rio Pastaza watershed.

6.
Zookeys ; 1134: 73-100, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761112

RESUMO

The rainfrogs of the genus Pristimantis are one of the most diverse groups of vertebrates, with outstanding reproductive modes and strategies driving their success in colonizing new habitats. The rate of Pristimantis species discovered annually has increased continuously during the last 50 years, establishing the remarkable diversity found in this genus. In this paper the specifics of publications describing new species in the group are examined, including authorship, author gender, year, language, journal, scientific collections, and other details. Detailed information on the descriptions of 591 species of Pristimantis published to date (June 2022) were analyzed and extracted. John D. Lynch and William E. Duellman are the most prolific authors, yet Latin American researchers have scaled up and continued the description processes since the 1990s. The most common language used for descriptions is English, followed by Spanish. The great majority of authors have described only one species. The largest proportion of authors who have participated in the descriptions is of Ecuadorian nationality. Ecuador is the country with the highest description rate per year (3.9% growth rate). Only 20% of the contributions have included women and only 2% have featured women as principal authors. 36.8% of the species described are in the Not Evaluated or Data Deficient categories under the IUCN global red list. The importance of enhancing the descriptions in Spanish is emphasized and the inclusion based on equal access to opportunities for female researchers in Pristimantis taxonomy is encouraged. In general, if the current trends in Pristimantis descriptions continue, in ten years, a total of 770 or more species described could be expected.


ResumenLas ranas de la lluvia del género Pristimantis es uno de los grupos de vertebrados más diversos, con una variedad de modos reproductivos y estrategias que impulsan su éxito en la colonización de nuevos hábitats. La tasa de especies de Pristimantis descubiertas anualmente ha aumentado continuamente durante los últimos 50 años, estableciendo la notable diversidad encontrada en este género. En este artículo, examinamos los detalles de las publicaciones que describen nuevas especies en el grupo, incluida la autoría, el año, el idioma, la revista, el género, las colecciones científicas y otros detalles. Analizamos y extrajimos información detallada sobre las descripciones de 591 especies de Pristimantis publicadas hasta la fecha (junio 2022). John D. Lynch y William E. Duellman son los autores más prolíficos, pero los investigadores latinoamericanos han ampliado y continuado los procesos de descripción desde la década de 1990. El idioma más común utilizado para las descripciones es el inglés, seguido del español. La gran mayoría de los autores han descrito una sola especie. La mayor proporción de autores que han participado en las descripciones es de nacionalidad ecuatoriana. Ecuador es el país con la tasa de descripción más alta por año (tasa de crecimiento del 3,9%). Solo el 20% de las contribuciones han incluido a mujeres y solo el 2% las ha presentado como autoras principales. El 36,8% de las especies descritas se encuentran en las categorías No evaluadas o Datos insuficientes de la lista roja mundial de la UICN. Destacamos la importancia de potenciar las descripciones en español y fomentar la inclusión de mujeres investigadoras en la taxonomía de Pristimantis. En general, si continúan las tendencias actuales en las descripciones de Pristimantis, en 10 años se podría esperar un total de 770 o más especies descritas.

7.
Biodivers Data J ; 10: e90146, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761564

RESUMO

The black soldier fly, Hermetiaillucens (Linnaeus, 1758), is a saprophagous species used to decompose organic matter. This study proposes a distribution model of H.illucens to illustrate its current and future distribution. The methodology includes data collection from the Global Biodiversity Information Facility (GBIF), complemented with iNaturalist, manual expert curation of occurrence records, six species distribution models algorithms and one ensemble model. The average temperature of the driest annual quarter and the precipitation of the coldest annual quarter were the key variables influencing the potential distribution of H.illucens. The distribution range is estimated to decrease progressively and their suitable habitats could change dramatically in the future due to global warming. On the other hand, current optimal habitats would become uninhabitable for the species, mainly at low latitudes. Under this scenario, the species is projected to move to higher latitudes and elevations in the future. The results of this study provide data on the distribution of H.illucens, facilitating its location, management and sustainable use in current and future scenarios.

8.
PLoS One ; 16(5): e0251027, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33956885

RESUMO

Ecuador is one of the most biodiverse countries in the world, but faces severe pressures and threats to its natural ecosystems. Numerous species have declined and require to be objectively evaluated and quantified, as a step towards the development of conservation strategies. Herein, we present an updated National Red List Assessment for amphibian species of Ecuador, with one of the most detailed and complete coverages for any Ecuadorian taxonomic group to date. Based on standardized methodologies that integrate taxonomic work, spatial analyses, and ecological niche modeling, we assessed the extinction risk and identified the main threats for all Ecuadorian native amphibians (635 species), using the IUCN Red List Categories and Criteria. Our evaluation reveals that 57% (363 species) are categorized as Threatened, 12% (78 species) as Near Threatened, 4% (26 species) as Data Deficient, and 27% (168 species) as Least Concern. Our assessment almost doubles the number of threatened species in comparison with previous evaluations. In addition to habitat loss, the expansion of the agricultural/cattle raising frontier and other anthropogenic threats (roads, human settlements, and mining/oil activities) amplify the incidence of other pressures as relevant predictors of ecological integrity. Potential synergic effects with climate change and emergent diseases (apparently responsible for the sudden declines), had particular importance amongst the threats sustained by Ecuadorian amphibians. Most threatened species are distributed in montane forests and paramo habitats of the Andes, with nearly 10% of them occurring outside the National System of Protected Areas of the Ecuadorian government. Based on our results, we recommend the following actions: (i) An increase of the National System of Protected Areas to include threatened species. (ii) Supporting the ex/in-situ conservation programs to protect species considered like Critically Endangered and Endangered. (iii) Focalizing research efforts towards the description of new species, as well as species currently categorized as Data Deficient (DD) that may turn out to be threatened. The implementation of the described actions is challenging, but urgent, given the current conservation crisis faced by amphibians.


Assuntos
Anfíbios , Espécies em Perigo de Extinção , Animais , Anuros , Bufonidae , Conservação dos Recursos Naturais/métodos , Bases de Dados como Assunto , Ecossistema , Equador , Espécies em Perigo de Extinção/estatística & dados numéricos
9.
Zootaxa ; 5072(4): 351-372, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35390861

RESUMO

We describe a new species of Pristimantis from southern Ecuador, province of Zamora Chinchipe. The new species is closely related to an undescribed species of Pristimantis from Reserva Tapichalaca, Ecuador and with species of a clade historically assigned to the P. unistrigatus species group, such as P. parvillus, P. luteolateralis, P. walkeri, among others. The new species of Pristimantis is a miniaturized new frog (females 17.11.1 mm; males 13.20.9 mm), characterized by the presence of -shaped scapular folds, with two subconical tubercles on the medial and posterior regions of folds; tympanic membrane and tympanic annulus present but not externally visible; a prominent rostral papilla present; upper eyelid with one elongated conical tubercle; a conical tubercle on heels; groin with orange or yellow spots. The new species of Pristimantis is distributed in a restricted area in the Cordillera del Condor, a highly-diverse mountain range threatened by multiple anthropogenic activities. We recommend assigning the new species to the Endangered IUCN threatened category because it is only known from three nearby localities within mining concessions.


Assuntos
Anuros , Aves , Distribuição Animal , Animais , Equador , Feminino , Masculino , Filogenia
10.
PeerJ ; 8: e9934, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062424

RESUMO

We describe two new species of salamanders of the genus Oedipina, subgenus Oedopinola, from two localities on the northwestern foothills of Ecuador, at elevations between 921 and 1,067 m. These are the southernmost members of the genus. We examined different museum collections and we found just three specimens of Oedipina from Ecuador, obtained throughout the history of herpetological collections in the country. We identify two of the three specimens as new species, but refrain from assigning a specific identity to the third, pending further study. Oedipina villamizariorum sp. n. is a medium-sized member of the genus, with a narrow, relatively pointed head and blunt snout; dorsolaterally oriented eyes, moderate in size; and digits that are moderately long and having pointed tips. Oedipina ecuatoriana sp. n., somewhat larger, has a narrow head and broadly rounded snout; this new species differs from all known Oedipina by the distinctive presence of paired prefrontal bones and a reduced phalangeal formula: 0-0-1-0; 0-1-2-1-1. We provide detailed descriptions of the osteology of both new species. Finally, we present a phylogenetic hypothesis for the genus, including one of the two new species, based on partial sequences of mitochondrial DNA.

11.
PeerJ ; 7: e7405, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31423356

RESUMO

We describe a new species of terrestrial frog of the genus Noblella from the eastern versants of the Ecuadorian Andes in the upper Pastaza watershed. Noblella naturetrekii sp. n. differs from its Ecuadorian congeners by the presence of a differentiated tympanic membrane and a weakly defined tympanic annulus, and eyelids with rounded tubercles. In addition, the new species is characterized by its blackish-dark brown ventral coloration scattered with little white dots and the absence of papillae at the tip of the fingers and toes. We provide a detailed description of the call and osteology of the new species. Finally, we present the most complete phylogeny of the genus, which confirms that Noblella is a non-monophyletic group.

12.
Zookeys ; 832: 113-133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30930648

RESUMO

We describe a new species of Pristimantis from the montane forest of the Río Zuñag Ecological Reserve, upper basin of the Pastaza River, Ecuador. Pristimantismallii sp. n. is characterized by a snout-vent length of 11.6-21.3 mm in adult males (n = 12), 22.6-34.3 mm in adult females (n = 8), and is compared morphologically and genetically with Pristimantismiktos and with other relevant species of Pristimantis. The new species is characterized by having skin on dorsum and flanks shagreen, distinctive scapular folds, snout broadly rounded in dorsal view, upper eyelid bearing one or two subconical tubercles and some rounded tubercles, dorsum and flanks light brown to brown, with irregular dark brown marks bounded by dirty cream and groin with irregular yellowish marks.


ResumenDescribimos una nueva especie de Pristimantis del bosque montano de la Reserva Ecológica Río Zuñag, cuenca alta del río Pastaza, Ecuador. Pristimantismallii sp. n es caracterizada por una longitud rostro-cloacal de 11.6­21.3 mm en machos adultos (n = 12), 22.6­34.3 mm en hembras adultas (n = 8), y es comparada morfológica y genéticamente con Pristimantismiktos y con otras especies relevantes de Pristimantis. La especie nueva se caracteriza por tener la piel del dorso y flancos finamente granular, pliegues escapulares distintivos, hocico redondeado en vista dorsal, párpado superior con uno dos tubérculos subcónicos y algunos redondeados, dorso y flancos café claro a café, con marcas irregulares café oscuras bordeadas de crema sucio y marcas irregulares amarillentas en las ingles.

13.
Zookeys ; (794): 135-163, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30416343

RESUMO

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 Anolisaequatorialis, and it is suggested that previous records of A.aequatorialis in Colombia correspond to the new species described herein.


ResumenDescribimos una nueva especie de Anolis de las estribaciones de los Andes del suroccidente de Colombia y noroccidente de Ecuador, entre los 1187 y 2353 metros de elevación. La nueva especie puede ser distinguida de otros Anolis por caracteres de escamación, osteología craneal, morfología hemipenial, y ADN nuclear y mitocondrial. La nueva especie es hermana de A.aequatorialis, por lo que sugerimos que los registros previos de A.aequatorialis en Colombia corresponden a la nueva especie descrita en este artículo.

14.
Zookeys ; (661): 91-123, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769604

RESUMO

We present a molecular phylogeny of snake genus Atractus, with an improved taxon sampling that includes 30 of the 140 species currently recognized. The phylogenetic tree supports the existence of at least three new species in the Pacific lowlands and adjacent Andean slopes of the Ecuadorian Andes, which we describe here. A unique combination of molecular, meristic and color pattern characters support the validity of the new species. With the newly acquired data, we propose and define the Atractus iridescens species group, as well as redefine the Atractus roulei species group. The species Atractus iridescens is reported for the first time in Ecuador, whereas Atractus bocourti and Atractus medusa are removed from the herpetofauna of this country. We provide the first photographic vouchers of live specimens for Atractus multicinctus, Atractus paucidens and Atractus touzeti, along with photographs of 19 other Ecuadorian Atractus species. The current status of Atractus occidentalis and Atractus paucidens is maintained based on the discovery of new material referable to these species. With these changes, the species number reported in Ecuador increases to 27, a number that is likely to increase as material not examined in this work becomes available and included in systematic studies.

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