RESUMEN
In this paper, we have performed an in-depth study of the complete set of the satellite DNA (satDNA) families (i.e. the satellitomes) in the genome of two barley species of agronomic value in a breeding framework, H. chilense (H1 and H7 accessions) and H. vulgare (H106 accession), which can be useful tools for studying chromosome associations during meiosis. The study has led to the analysis of a total of 18 satDNA families in H. vulgare, 25 satDNA families in H. chilense (accession H1) and 27 satDNA families in H. chilense (accession H7) that constitute 46 different satDNA families forming 36 homology groups. Our study highlights different important contributions of evolutionary and applied interests. Thus, both barley species show very divergent satDNA profiles, which could be partly explained by the differential effects of domestication versus wildlife. Divergence derives from the differential amplification of different common ancestral satellites and the emergence of new satellites in H. chilense, usually from pre-existing ones but also random sequences. There are also differences between the two H. chilense accessions, which support genetically distinct groups. The fluorescence in situ hybridization (FISH) patterns of some satDNAs yield distinctive genetic markers for the identification of specific H. chilense or H. vulgare chromosomes. Some of the satellites have peculiar structures or are related to transposable elements which provide information about their origin and expansion. Among these, we discuss the existence of different (peri)centromeric satellites that supply this region with some plasticity important for centromere evolution. These peri(centromeric) satDNAs and the set of subtelomeric satDNAs (a total of 38 different families) are analyzed in the framework of breeding as the high diversity found in the subtelomeric regions might support their putative implication in chromosome recognition and pairing during meiosis, a key point in the production of addition/substitution lines and hybrids.
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Cromosomas de las Plantas , ADN Satélite , Hordeum , Hibridación Fluorescente in Situ , Hordeum/genética , ADN Satélite/genética , Cromosomas de las Plantas/genética , ADN de Plantas/genética , Genoma de Planta/genética , Filogenia , Variación Genética , Meiosis/genética , Evolución Molecular , Especificidad de la EspecieRESUMEN
Hemipenes are important structures for the systematics of Squamata, and may assist in the diagnosis of closely related taxa. Only one of the species of Glaucomastix (G. venetacauda) had its hemipenial morphology described in literature so far. Here we analyze and describe for the first time the hemipenes of seven specimens of G. abaetensis and 20 specimens of G. littoralis from the reptile collection of Museu Nacional, Universidade Federal do Rio de Janeiro. In both species the hemipenes are bilobed with a forked sulcus spermaticus in a centripetal orientation and present laminar ornamentations on the hemipenial body and paired awns on the apical region of the lobes. The two species differed from each other only in the modal number of proximal laminae. The main differences in hemipenial morphology between Glaucomastix and its sister genus Ameivula are the presence of laminae in the hemipenial body (absent in Ameivula) and the absence of digitiform papillae on the apical lobular region (present in Ameivula). We expect that our data can be used as an additional tool to diagnose species within the genus Glaucomastix/Ameivula.
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Lagartos , Animales , Lagartos/anatomía & histología , Lagartos/clasificación , Masculino , Femenino , Especificidad de la Especie , BrasilRESUMEN
Climaciella Enderlein is a genus of the family Mantispidae (Neuroptera) restricted to the New World with records ranging from southern Canada to northern Argentina. The genus is currently represented by 12 valid species, three of them with records from Brazil: C. amapaensis Penny, C. duckei Navás, and C. semihyalina (Le Peletier & Audinet-Serville). Besides the relatively low number of species from Brazil, it is known that Climaciella species present some historical taxonomic problems. In this sense, the main goal of this study was to taxonomically revise the Climaciella species from Brazil, providing detailed (re)descriptions and illustrations of all species, an updated distribution map, and an identification key to the whole genus. The study resulted in some new taxonomic acts: C. tincta (Navás) is revalidated and C. duckei is considered a new synonym of C. tincta; two new species are described: Climaciella hoffmani sp. nov. and Climaciella pennyi sp. nov.
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Distribución Animal , Brasil , Animales , Masculino , Femenino , Especificidad de la EspecieRESUMEN
BACKGROUND: Hybrids are expected to show greater phenotypic variation than their parental species, yet how hybrid phenotype expression varies with genetic distances in closely-related parental species remains surprisingly understudied. Here, we investigate pelage and morphometric trait variation in anthropogenic hybrids between four species of Brazilian Callithrix marmosets, a relatively recent primate radiation. Marmoset species are distinguishable by pelage phenotype and morphological specializations for eating tree exudates. In this work, we (1) describe qualitative phenotypic pelage differences between parental species and hybrids; (2) test whether significant quantitative differences exist between parental and hybrid morphometric phenotypes; and (3) determine which hybrid morphometic traits show heterosis, dysgenesis, trangression, or intermediacy relative to the parental trait. We investigated cranial and post-cranial morphometric traits, as most hybrid morphological studies focus on the former instead of the latter. Finally, we estimate mitogenomic distances between marmoset species from previously published data. RESULTS: Marmoset hybrid facial and overall body pelage variation reflected novel combinations of coloration and patterns present in parental species. In morphometric traits, C. jacchus and C. penicillata were the most similar, while C. aurita was the most distinct, and C. geoffroyi trait measures fell between these species. Only three traits in C. jacchus x C. penicillata hybrids showed heterosis. We observed heterosis and dysgenesis in several traits of C. penicillata x C. geoffroyi hybrids. Transgressive segregation was observed in hybrids of C. aurita and the other species. These hybrids were also C. aurita-like for a number of traits, including body length. Genetic distance was closest between C. jacchus and C. penicillata and farthest between C. aurita and the other species. CONCLUSION: We attributed significant morphometric differences between marmoset species to variable levels of morphological specialization for exudivory in these species. Our results suggest that intermediate or parental species-like hybrid traits relative to the parental trait values are more likely in crosses between species with relatively lesser genetic distance. More extreme phenotypic variation is more likely in parental species with greater genetic distance, with transgressive traits appearing in hybrids of the most genetically distant parental species. We further suggest that fewer developmental disturbances can be expected in hybrids of more recently diverged parental species, and that future studies of hybrid phenotypic variation should investigate selective pressures on Callithrix cranial and post-cranial morphological traits.
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Callithrix , Hibridación Genética , Fenotipo , Animales , Callithrix/anatomía & histología , Callithrix/genética , Masculino , Femenino , Brasil , Vigor Híbrido/genética , Especificidad de la EspecieRESUMEN
Predicting how plants respond to drought requires an understanding of how physiological mechanisms and drought response strategies occur, as these strategies underlie rates of gas exchange and productivity. We assessed the response of 11 plant traits to repeated experimental droughts in four co-occurring species of central Australia. The main goals of this study were to: (i) compare the response to drought between species; (ii) evaluate whether plants acclimated to repeated drought; and (iii) examine the degree of recovery in leaf gas exchange after cessation of drought. Our four species of study were two tree species and two shrub species, which field studies have shown to occupy different ecohydrological niches. The two tree species (Eucalyptus camaldulensis Dehnh. and Corymbia opaca (D.J.Carr & S.G.M.Carr) K.D.Hill & L.A.S.Johnson) had large reductions in stomatal conductance (gs) values, declining by 90% in the second drought. By contrast, the shrub species (Acacia aptaneura Maslin & J.E.Reid and Hakea macrocarpa A.Cunn. ex R.Br.) had smaller reductions gs in the second drought of 52 and 65%, respectively. Only A. aptaneura showed a physiological acclimatation to drought due to small declines in gs versus á´ªpd (0.08 slope) during repeated droughts, meaning they maintained higher rates of gs compared with plants that only experienced one final drought (0.19 slope). All species in all treatments rapidly recovered leaf gas exchange and leaf mass per area following drought, displaying physiological plasticity to drought exposure. This research refines our understanding of plant physiological responses to recurrent water stress, which has implications for modelling of vegetation, carbon assimilation and water use in semi-arid environments under drought.
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Sequías , Hojas de la Planta , Árboles , Hojas de la Planta/fisiología , Árboles/fisiología , Australia , Transpiración de Plantas/fisiología , Especificidad de la Especie , Aclimatación/fisiologíaRESUMEN
Spiders of Loxosceles genus, or Brown spiders produce a potent venom with minimal volume and protein content. Among its toxins, phospholipases D (PLDs) are notable for causing primary local and systemic manifestations observed following envenomation. They degrade cellular phospholipids, mainly sphingomyelin and lysophosphatidylcholine. We present a robust and detailed analysis of PLD transcripts from venom glands of three major clinically relevant South American species-L. intermedia, L. laeta, and L. gaucho-using next-generation sequencing. Results confirmed that PLDs are the most highly expressed toxins, accounting for 65.4 % of expression in L. intermedia, 71.8 % in L. gaucho, and 50.4 % in L. laeta. These findings further support the idea that these enzymes form a protein family both within and across species. Eighteen contigs for PLDs were found for L. gaucho, 24 for L. intermedia, and 21 for L. laeta. A detailed analysis revealed that, although all contigs display conserved amino acid residues directly involved in catalysis, magnesium coordination, and substrate affinity, they also possess distinct primary sequences with important substitutions. Such data reinforces the hypothesis that these toxins may act synergistically. Furthermore, new PLD sequences were identified within the contigs. For L. intermedia, 14 potential new isoforms were identified; 16 for L gaucho; and 16 novel sequences for L. laeta. This indicates that there is still a wealth of undisclosed information about these toxins. These data will help identify structural and functional differences among these proteins, support future functional studies, and to the comprehensive understanding of the mechanism of action of PLDs.
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Fosfolipasa D , Venenos de Araña , Fosfolipasa D/genética , Fosfolipasa D/metabolismo , Fosfolipasa D/química , Animales , Venenos de Araña/genética , Venenos de Araña/enzimología , Filogenia , Secuencia de Aminoácidos , Isoenzimas/genética , Isoenzimas/metabolismo , Arañas/genética , Arañas/enzimología , Especificidad de la Especie , Araña Reclusa Parda , Perfilación de la Expresión Génica , Transcriptoma , Isoformas de Proteínas/genética , Hidrolasas Diéster FosfóricasRESUMEN
The aim of this work was to develop a real-time PCR assay with a TaqMan® probe that detects a species-specific part of the 16S rDNA gene of Ehrlichia canis. Canine blood samples (n = 207), collected and tested by a conventional PCR assay within a study conducted by De Salvo et al., were simultaneously analyzed with the novel designed real-time PCR, and the results of both assays were compared. The agreement between the two methods was 97.6 % with a kappa value of 0.92186. Hereby, the standard error was 0.034416 and the 95 % confidence interval from 0.8544 to 0.98931. While the conventional PCR assay showed false negative results (2.42 %; 5/207), the real-time PCR assays showed a specificity of 100 %. The results of the current study showed that the developed assay presents sensitivity and specificity for the detection of E. canis in blood samples, adding a new tool for the diagnosis of this pathogen.
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Enfermedades de los Perros , Ehrlichia canis , Ehrlichiosis , Reacción en Cadena en Tiempo Real de la Polimerasa , Ehrlichia canis/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Especificidad de la Especie , ARN Ribosómico 16S/genética , Ehrlichiosis/diagnóstico , Ehrlichiosis/veterinaria , Sensibilidad y Especificidad , Animales , Perros , Garrapatas/microbiología , Enfermedades de los Perros/diagnósticoRESUMEN
Ergasilus lizae Krøyer, 1863 is a parasitic copepod known to infect mullets (Mugilidae) in different parts of the world. It was originally reported from the east coast of North America, but the original description lacks enough detail, making identification with this information difficult. In this study, we provide a redescription of E. lizae found on Mugil curema Valenciennes and M. cephalus Linnaeus, caught in two coastal lagoons of northwestern Mexico during two climatic seasons: warm/rainy and cold/dry. The prevalence of this parasite was higher in the warm season than in the cold season. To facilitate the species identification, new sequences of the barcoding gene (COI mtDNA) of E. lizae were generated and compared against unpublished sequences of E. lizae available in the Barcode of Life Database (BOLD). Our results suggest that the sequences of BOLD possibly belong to a species misidentified as E. lizae.
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Copépodos , Código de Barras del ADN Taxonómico , Estaciones del Año , Especificidad de la Especie , Animales , Copépodos/genética , Copépodos/anatomía & histología , Copépodos/clasificación , México , Smegmamorpha/parasitología , Filogenia , Complejo IV de Transporte de Electrones/genéticaRESUMEN
A taxonomic study of deep-sea polychaetes collected at a depth of 2,805 m off the northern coast of California revealed a scaleworm of the family Sigalionidae with an attached parasitic copepod. The copepod represents an undescribed genus of the family Herpyllobiidae, comprising mesoparasitic copepods chiefly recorded from polychaetes of the family Polynoidae. Blakerius gen. nov. diverges from the other herpyllobiid genera by its possession of 1) a chalice-shaped ectosoma with several protuberances along the posterior margin and a long cylindrical shaft with a hyaline coating and integumental sculpturing, a short stalk with a small, anteriorly placed sclerotized ring, 2) a relatively large, discoid-shaped endosoma with digitiform process, and 3) attached male copepodids with 3-segmented antennules, containing limbless sac-like males. The new genus is compared with other herpyllobiids. This discovery increases the number of known herpyllobiid genera to six and is the first record of a herpyllobiid parasitizing a sigalionid polychaete.urn: lsid: zoobank.org:pub:5E31FEED-D3EB-460E-AEA4-02A9D3A778D6.
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Copépodos , Poliquetos , Especificidad de la Especie , Animales , Copépodos/clasificación , Copépodos/anatomía & histología , Poliquetos/parasitología , Masculino , California , FemeninoRESUMEN
In 1937, Travassos described a new species of nematode in the genus Longistriata Schulz, 1926. He referred to it seven times as L. zetta in the main text, but also five times as L. zeta in the figure legends. This nominal species is currently assigned to the genus Guerrerostrongylus Sutton and Durette-Desset, 1991. The complete bibliography referring to this species from 1937 to date comprises only 22 works. Although the spelling 'zetta' has prevailed since 2011, the correct original spelling of its specific name remains unsettled. Acting as First Revisers under Articles 24.2.3 and 32.2.1 of the International Code of Zoological Nomenclature, we hereby choose 'zeta' as the correct original spelling of the specific name of this nematode, thus rendering 'zetta' an unavailable incorrect spelling. In making this choice, we have taken into account Travassos' obvious intention to name the species after the sixth letter of the Greek alphabet and the longer use of the spelling 'zeta' in the relevant literature, especially in those works in which 'zeta' (never 'zetta') was first combined with other generic names. We believe that standardizing the use of the spelling 'zeta' as the correct original spelling is the best way to stabilize this name.
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Terminología como Asunto , Animales , Roedores/parasitología , América del Sur , Especificidad de la Especie , Heligmosomatoidea/clasificación , Heligmosomatoidea/anatomía & histologíaRESUMEN
Centrolenidae is a Neotropical family widely distributed in Central and South America, with its species richness concentrated in the tropical Andes. Several taxonomic problems have been identified within this family, mostly related to species with broad geographic distributions. In this study, we assessed and redefined the species boundaries of the Centrolene buckleyi species complex, and formally described two new species from the Andes of Ecuador. These new taxa are recognized by a combination of morphometric, osteological, acoustic, and genetic data. Following IUCN criteria, we propose that the two new species should to be considered as Endangered (EN), mainly because of their small distributions and habitat loss. The C. buckleyi complex provides insights into the biogeography of closely related Andean species. As in other glassfrogs, speciation in Centrolene seems to be mediated by the linearity of the Andes, where gene flow can be restricted by topography and, also, local extinctions.
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Anuros , Animales , Anuros/genética , Anuros/anatomía & histología , Anuros/clasificación , Ecosistema , Ecuador , Especies en Peligro de Extinción , Filogenia , Especificidad de la EspecieRESUMEN
Coral reefs rely heavily on reef fish for their health, yet overfishing has resulted in their decline, leading to an increase in fast-growing algae and changes in reef ecosystems, a phenomenon described as the phase-shift. A clearer understanding of the intricate interplay between herbivorous, their food, and their gut microbiomes could enhance reef health. This study examines the gut microbiome and isotopic markers (δ13C and δ15N) of four key nominally herbivorous reef fish species (Acanthurus chirurgus, Kyphosus sp., Scarus trispinosus, and Sparisoma axillare) in the Southwestern Atlantic's Abrolhos Reef systems. Approximately 16.8 million 16S rRNA sequences were produced for the four fish species, with an average of 317,047 ± 57,007 per species. Bacteria such as Proteobacteria, Firmicutes, and Cyanobacteria were prevalent in their microbiomes. These fish show unique microbiomes that result from co-diversification, diet, and restricted movement. Coral-associated bacteria (Endozoicomonas, Rhizobia, and Ruegeria) were found in abundance in the gut contents of the parrotfish species Sc. trispinosus and Sp. axillare. These parrotfishes could aid coral health by disseminating such beneficial bacteria across the reef. Meanwhile, Kyphosus sp. predominantly had Pirellulaceae and Rhodobacteraceae. Four fish species had a diet composed of turf components (filamentous Cyanobacteria) and brown algae (Dictyopteris). They also had similar isotopic niches, suggesting they shared food sources. A significant difference was observed between the isotopic signature of fish muscular gut tissue and gut contents, pointing to the role that host genetics and gut microbes play in differentiating fish tissues.
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Bacterias , Arrecifes de Coral , Peces , Microbioma Gastrointestinal , ARN Ribosómico 16S , Animales , ARN Ribosómico 16S/genética , Peces/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Herbivoria , Especificidad de la Especie , Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisis , Perciformes/microbiología , Dieta/veterinariaRESUMEN
Background: Plants allocate resources to growth, defense, and stress resistance, and resource availability can affect the balance between these allocations. Allocation patterns are well-known to differ among species, but what controls possible intra-specific trade-offs and if variation in growth vs. defense potentially evolves in adaptation to resource availability. Methods: We measured growth and defense in a provenance trial of rubber trees (Hevea brasiliensis) with clones originating from the Amazon basin. To test hypotheses on the allocation to growth vs. defense, we relate biomass growth and latex production to wood and leaf traits, to climate and soil variables from the location of origin, and to the genetic relatedness of the Hevea clones. Results: Contrary to expectations, there was no trade-off between growth and defense, but latex yield and biomass growth were positively correlated, and both increased with tree size. The absence of a trade-off may be attributed to the high resource availability in a plantation, allowing trees to allocate resources to both growth and defense. Growth was weakly correlated with leaf traits, such as leaf mass per area, intrinsic water use efficiency, and leaf nitrogen content, but the relative investment in growth vs. defense was not associated with specific traits or environmental variables. Wood and leaf traits showed clinal correlations to the rainfall and soil variables of the places of origin. These traits exhibited strong phylogenetic signals, highlighting the role of genetic factors in trait variation and adaptation. The study provides insights into the interplay between resource allocation, environmental adaptations, and genetic factors in trees. However, the underlying drivers for the high variation of latex production in one of the commercially most important tree species remains unexplained.
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Hevea , Látex , Hojas de la Planta , Hevea/genética , Hevea/crecimiento & desarrollo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Látex/metabolismo , Biomasa , Madera/genética , Filogenia , Especificidad de la EspecieRESUMEN
Rodents have received substantial attention in the study of olfaction. However, the rhinarium, the naked part of the nose, which plays an important role in chemical, tactile, and thermal perception, has been relatively overlooked. This study presents a comprehensive analysis of the rhinarium morphology and spatially associated structures (i.e., upper lip, and philtrum) in sigmodontines, a diverse group within the Cricetidae rodents. The research covers 483 specimens representing 145 species, accounting for 74% of genera in the clade, including all 13 recognized tribes, three incertae sedis genera, and the murid representatives Mus musculus and Rattus norvegicus. The inconsistent use of terminology in describing rhinarium traits across the literature poses a challenge for comparative analyzes. To address this issue, a standardized terminology was proposed to characterize the rhinarium. A paired complex protuberance typically with epidermal ridges (i.e., rhinoglyphics), termed here the tubercle of Hill, was identified as a distinctive feature in muroid rhinaria. Comparative assessments among tribes revealed unique sets of features defining each major clade, encompassing variations in hairiness, dorsum nasi complexity, size and positioning of the tubercle of Hill, and other key attributes. Two primary rhinarium configurations were discerned: one shared by Oryzomyalia and Sigmodontini and another specific to Ichthyomyini. The former groups display a ventrally positioned rhinarium prominently featuring the tubercle of Hill and sculptured areola circularis. In contrast, Ichthyomyini exhibit a frontally directed rhinarium characterized by an enlarged dorsum nasi fused to the tubercle of Hill, resulting in a distinctive "cherry" appearance. Convergent rhinarium structures observed in fossorial species, characterized by well-developed plica alaris and hair fringes, are presumed to mitigate potential damage during digging. Conversely, semiaquatic carnivorous sigmodontines showcase an integrated apical structure in their rhinarium, facilitating enhanced somatosensory capabilities crucial for predation activities during diving expeditions.
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Nariz , Filogenia , Animales , Nariz/anatomía & histología , Labio/anatomía & histología , Sigmodontinae/anatomía & histología , Terminología como Asunto , Ratas/anatomía & histología , Especificidad de la EspecieRESUMEN
In cave environments, stable conditions devoid of light-dark cycles and temperature fluctuations sustain circadian clock mechanisms across various species. However, species adapted to these conditions may exhibit disruption of circadian rhythm in locomotor activity. This study examines potential rhythm loss due to convergent evolution in five semi-aquatic troglobitic isopod species (Crustacea: Styloniscidae), focusing on its impact on locomotor activity. The hypothesis posits that these species display aperiodic locomotor activity patterns. Isopods were subjected to three treatments: constant red light (DD), constant light (LL), and light-dark cycles (LD 12:12), totaling 1656 h. Circadian rhythm analysis employed the Sokolove and Bushell periodogram chi-square test, Hurst coefficient calculation, intermediate stability (IS), and activity differences for each species. Predominantly, all species exhibited an infradian rhythm under DD and LL. There was synchronization of the locomotor rhythm in LD, likely as a result of masking. Three species displayed diurnal activity, while two exhibited nocturnal activity. The Hurst coefficient indicated rhythmic persistence, with LD showing higher variability. LD conditions demonstrated higher IS values, suggesting synchronized rhythms across species. Significant individual variations were observed within species across the three conditions. Contrary to the hypothesis, all species exhibited synchronization under light-dark conditions. Analyzing circadian activity provides insights into organism adaptation to non-cyclical environments, emphasizing the importance of exploring underlying mechanisms.
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Cuevas , Ritmo Circadiano , Isópodos , Locomoción , Fotoperiodo , Animales , Ritmo Circadiano/fisiología , Isópodos/fisiología , Locomoción/fisiología , Especificidad de la Especie , Luz , Actividad Motora/fisiología , Conducta Animal/fisiologíaRESUMEN
We studied the relationship between shape, size, and developmental time in the embryonic ontogeny of 15 species of the frog genus Physalaemus. As in other anuran exotrophic embryos, shape changes are correlated with size increase and mainly concern tail elongation, decrease in body height, and increase in fin height. Size ranges and developmental times vary interspecifically. Embryos of the P. signifer Clade and the P. gracilis Group are among the largest, are slightly peramorphic, and develop fast regarding congeneric species. Embryos of P. cicada combine the smallest sizes with fast development and the most peramorphic shapes. The paedomorphic shapes of embryos of P. biligonigerus and P. henselii groups are correlated with fast vs. slow developmental times respectively. Trajectories in the P. cuvieri Group are diverse and in general differ in size and developmental time. The embryos of P. cristinae and from the Argentinean lineage of P. cuvieri stand out with the longest development. Sequences of developmental events are overall conserved in the genus, and main differences concern mouthpart ontogeny. This study constitutes the first attempt to evaluate morphological, allometric, and heterochronic parameters of the early ontogeny of anurans and how these can vary and contribute to diversification in taxonomic groups.
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Anuros , Animales , Anuros/anatomía & histología , Anuros/clasificación , Anuros/embriología , Anuros/crecimiento & desarrollo , Embrión no Mamífero/anatomía & histología , Especificidad de la Especie , Desarrollo Embrionario , Factores de TiempoRESUMEN
This study focuses on the acoustic classification of delphinid species at the southern continental slope of Brazil. Recordings were collected between 2013 and 2015 using towed arrays and were processed using a classifier to identify the species in the recordings. Using Raven Pro 1.6 software (Cornell Laboratory of Ornithology, Ithaca, NY), we analyzed whistles for species identification. The random forest algorithm in R facilitates classification analysis based on acoustic parameters, including low, high, delta, center, beginning, and ending frequencies, and duration. Evaluation metrics, such as correct and incorrect classification percentages, global accuracy, balanced accuracy, and p-values, were employed. Receiver operating characteristic curves and area-under-the-curve (AUC) values demonstrated well-fitting models (AUC ≥ 0.7) for species definition. Duration and delta frequency emerged as crucial parameters for classification, as indicated by the decrease in mean accuracy. Multivariate dispersion plots visualized the proximity between acoustic and visual match data and exclusively acoustic encounter (EAE) data. The EAE results classified as Delphinus delphis (n = 6), Stenella frontalis (n = 3), and Stenella longirostris (n = 2) provide valuable insights into the presence of these species between approximately 23° and 34° S in Brazil. This study demonstrates the effectiveness of acousting classification in discriminating delphinids through whistle parameters.
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Acústica , Delfines , Vocalización Animal , Animales , Vocalización Animal/clasificación , Océano Atlántico , Delfines/clasificación , Delfines/fisiología , Espectrografía del Sonido , Brasil , Especificidad de la Especie , Procesamiento de Señales Asistido por ComputadorRESUMEN
The genus Rhinella corresponds to a group of anurans characterized by numerous taxonomic and systemic challenges, leading to their organization into species complexes. Cytogenetic data for this genus thus far are limited to the diploid number and chromosome morphology, which remain highly conserved among the species. In this study, we analyse the karyotypes of three species of the genus Rhinella (Rhinella granulosa, Rhinella margaritifera, and Rhinella marina) using both classical (conventional staining and C-banding) and molecular (FISH-fluorescence in situ hybridization with 18S rDNA, telomeric sequences, and microsatellite probes) cytogenetic approaches. The aim of this study is to provide data that can reveal variations in the distribution of repetitive sequences that can contribute to understanding karyotypic diversification in these species. The results revealed a conserved karyotype across the species, with 2n = 22 and FN = 44, with metacentric and submetacentric chromosomes. C-banding revealed heterochromatic blocks in the pericentromeric region for all species, with a proximal block on the long arms of pairs 3 and 6 in R. marina and on the short arms of pairs 4 and 6 in R. margaritifera. Additionally, 18S rDNA probes hybridized to pair 5 in R. granulosa, to pair 7 in R. marina, and to pair 10 in R. margaritifera. Telomeric sequence probes displayed signals exclusively in the distal region of the chromosomes, while microsatellite DNA probes showed species-specific patterns. These findings indicate that despite a conserved karyotypical macrostructure, chromosomal differences exist among the species due to the accumulation of repetitive sequences. This variation may be attributed to chromosome rearrangements or differential accumulation of these sequences, highlighting the dynamic role of repetitive sequences in the chromosomal evolution of Rhinella species. Ultimately, this study emphasizes the importance of the role of repetitive DNAs in chromosomal rearrangements to elucidate the evolutionary mechanisms leading to independent diversification in the distinct phylogenetic groups of Rhinella.
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Análisis Citogenético , Hibridación Fluorescente in Situ , Cariotipo , Repeticiones de Microsatélite , Animales , Repeticiones de Microsatélite/genética , Bufonidae/genética , Bufonidae/clasificación , Femenino , ARN Ribosómico 18S/genética , Telómero/genética , Especificidad de la Especie , Bandeo Cromosómico , Cariotipificación , Masculino , ADN Ribosómico/genéticaRESUMEN
Here we present a taxonomic treatment for the Brazilian species of Syrbatus (Reitter, 1882), including the description of three new species (Syrbatus moustache Asenjo & Valois sp. nov., Syrbatus obsidian Asenjo & Valois sp. nov. and Syrbatus superciliata Asenjo & Valois sp. nov.) from the Quadrilátero Ferrífero (Minas Gerais, Brazil). In addition, we designated lectotypes for the Brazilian species of species-group 2, Syrbatus centralis (Raffray, 1898), Syrbatus hetschkoi (Reitter, 1888), Syrbatus hiatusus (Reitter, 1888), Syrbatus transversalis (Raffray, 1898), and Syrbatus trinodulus (Schaufuss, 1887), besides recognizing the holotype for Syrbatus brevispinus (Reitter, 1882), Syrbatus bubalus (Raffray, 1898), and Syrbatus grouvellei (Raffray, 1898). The mitochondrial genomes (mitogenomes) of the three new species are presented, for which we present the phylogenetic placement among Staphylinidae with previously published data.
Asunto(s)
Escarabajos , Genoma Mitocondrial , Filogenia , Animales , Escarabajos/genética , Escarabajos/clasificación , Genoma Mitocondrial/genética , Brasil , Masculino , Femenino , Especificidad de la EspecieRESUMEN
Parasmittina is the most representative cheilostome genus of the family Smittinidae, often reported in the fouling non-indigenous marine community. Here, we present a review of Parasmittina species reported in the Southwestern Atlantic including the characterization of one species from Argentina (P. dubitata) and ten from the Brazilian coast: P. abrolhosensis, P. alba, P. bimucronata, P. ligulata comb. nov., P. longirostrata, P. pinctatae, P. serrula, P. simpulata, P. winstonae and the new species Parasmittina falciformis sp. nov. The new species is characterized by a smooth distally primary orifice with 1-2 oral spines, large lyrula, serrated condyles with hooked tips, and two types of avicularia-small and subtriangular and large sublanceolate. This study does not recognize four species previous recorded in Brazil: reports of P. betamorphaea and P. trispinosa are now assigned to P. pinctatae; records of P. munita belong to P. falciformis sp. nov.; and reports of P. spathulata encompass at least two taxa, including P. abrolhosensis and P. simpulata. In this study, five species complexes (P. alba, P. longirostrata, P. serrula, P. simpulata and P. winstonae) were identified and require further investigations. While six species characterized here were first described based on specimens from the Southwestern Atlantic (P. abrolhosensis, P. alba, P. dubitata, P. ligulata comb. nov., P. simpulata and P. falciformis sp. nov.), the remaining species are mainly known from the Indo-Pacific. These taxa are here recognized as exotic (P. longirostrata) and cryptogenic (P. bimucronata, P. pinctatae, P. serrula and P. winstonae) in the studied area. Most of the non-native taxa are widespread along the Brazilian coast, growing on both artificial and natural surfaces, indicating that they are well-established in the area. As non-native bryozoans can negatively influence the environment, affecting human economic activities and beach usage, further studies on the fauna presented here are suggested to determine the origin of these taxa and help prevent bioinvasion events along the SW Atlantic.