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1.
Rev. biol. trop ; Rev. biol. trop;71abr. 2023.
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1514953

RESUMEN

Introduction: Species of Mesochorus are found worldwide and members of this genus are primarily hyperparasitoids of Ichneumonoidea and Tachinidae. Objectives: To describe species of Costa Rican Mesochorus reared from caterpillars and to a lesser extent Malaise-trapped. Methods: The species are diagnosed by COI mtDNA barcodes, morphological inspection, and host data. A suite of images and host data (plant, caterpillar, and primary parasitoid) are provided for each species. Results: A total of 158 new species of Mesochorus. Sharkey is the taxonomic authority for all. Conclusions: This demonstrates a practical application of DNA barcoding that can be applied to the masses of undescribed neotropical insect species in hyperdiverse groups.


Introducción: Las especies de Mesochorus se encuentran en todo el mundo y los miembros de este género son principalmente hiperparasitoides de las familias Ichneumonoidea y Tachinidae. Objetivos: Describir las especies de Mesochorus costarricenses obtenidas de orugas y en menor medida por trampas Malaise. Métodos: Las especies se diagnosticaron mediante el uso de código de barra molecular por COI del ADNmt, inspección morfológica y datos del huésped. Se proporciona un conjunto de imágenes y datos de los huéspedes (planta, oruga y parasitoide primario) para cada especie. Resultados: Se encontró un total de 158 nuevas especies de Mesochorus. Sharkey es la autoridad taxonómica para todas las especies. Conclusiones: Se demuestra una aplicación práctica del código de barras de ADN que se puede aplicar a grandes cantidades de especies de insectos neotropicales no descritas para grupos hiperdiversos.


Asunto(s)
Animales , Himenópteros/clasificación , Costa Rica , Código de Barras del ADN Taxonómico
2.
Ecohealth ; 16(1): 128-140, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30377876

RESUMEN

The fungus Batrachochytrium dendrobatidis (Bd) is a generalist amphibian pathogen responsible for chytridiomycosis. It was documented for the first time in Cuba in 2007, the apparent cause of the decline in one species of toad. In a recent survey, Bd was reported only for the highlands of Central Cuba. In the present study, we reexamined the geographic distribution and level of impact of Bd in Cuba by conducting an island-wide sampling in 10 localities and collecting skin swabs from 18 species and 28 environmental samples. We report detection of Bd in 60% of sampled sites and in 58% of sampled taxa. We show that Bd is associated with riparian, arboreal and terrestrial species, and it was estimated to occur in approximately 30% of the aquatic habitats we sampled. In addition, we confirmed that a dying individual of the species Eleutherodactylus casparii was severely infected with Bd. We also rise concern about the endanger toad Peltophryne longinasus and about three species of endemic riparian frogs that were not detected during our surveys. This study demonstrates that this pathogen is widespread throughout Cuba and provides relevant evidence to advance our understanding of its detection in amphibians and the aquatic environment in Cuba and about the occurrence of Bd in species with different ecologies. We provide valuable baseline information for Bd risk assessment and decision-making processes to mitigate its negative impact on Cuban amphibians.


Asunto(s)
Anfibios/microbiología , Quitridiomicetos/aislamiento & purificación , Micosis/veterinaria , Animales , Clima , Cuba/epidemiología , ADN de Hongos , Ecosistema , Ríos
3.
Proc Natl Acad Sci U S A ; 114(31): 8313-8318, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28716927

RESUMEN

DNA sequencing brings another dimension to exploration of biodiversity, and large-scale mitochondrial DNA cytochrome oxidase I barcoding has exposed many potential new cryptic species. Here, we add complete nuclear genome sequencing to DNA barcoding, ecological distribution, natural history, and subtleties of adult color pattern and size to show that a widespread neotropical skipper butterfly known as Udranomia kikkawai (Weeks) comprises three different species in Costa Rica. Full-length barcodes obtained from all three century-old Venezuelan syntypes of U. kikkawai show that it is a rainforest species occurring from Costa Rica to Brazil. The two new species are Udranomia sallydaleyae Burns, a dry forest denizen occurring from Costa Rica to Mexico, and Udranomia tomdaleyi Burns, which occupies the junction between the rainforest and dry forest and currently is known only from Costa Rica. Whereas the three species are cryptic, differing but slightly in appearance, their complete nuclear genomes totaling 15 million aligned positions reveal significant differences consistent with their 0.00065-Mbp (million base pair) mitochondrial barcodes and their ecological diversification. DNA barcoding of tropical insects reared by a massive inventory suggests that the presence of cryptic species is a widespread phenomenon and that further studies will substantially increase current estimates of insect species richness.


Asunto(s)
Mariposas Diurnas/clasificación , Mariposas Diurnas/genética , Código de Barras del ADN Taxonómico/métodos , ADN Mitocondrial/genética , Mariposas Nocturnas/clasificación , Mariposas Nocturnas/genética , Animales , Secuencia de Bases , Biodiversidad , Costa Rica , Complejo IV de Transporte de Electrones/genética , Filogenia , Análisis de Secuencia de ADN , Clima Tropical
4.
BMC Evol Biol ; 14: 153, 2014 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-25005355

RESUMEN

BACKGROUND: Skipper butterflies (Hesperiidae) are a relatively well-studied family of Lepidoptera. However, a combination of DNA barcodes, morphology, and natural history data has revealed several cryptic species complexes within them. Here, we investigate three DNA barcode lineages of what has been identified as Urbanus belli (Hesperiidae, Eudaminae) in Área de Conservación Guanacaste (ACG), northwestern Costa Rica. RESULTS: Although no morphological traits appear to distinguish among the three, congruent nuclear and mitochondrial lineage patterns show that "Urbanus belli" in ACG is a complex of three sympatric species. A single strain of Wolbachia present in two of the three cryptic species indicates that Urbanus segnestami Burns (formerly Urbanus belliDHJ01), Urbanus bernikerni Burns (formerly Urbanus belliDHJ02), and Urbanus ehakernae Burns (formerly Urbanus belliDHJ03) may be biologically separated by Wolbachia, as well as by their genetics. Use of parallel sequencing through 454-pyrosequencing improved the utility of ITS2 as a phylogenetic marker and permitted examination of the intra- and interlineage relationships of ITS2 variants within the species complex. Interlineage, intralineage and intragenomic compensatory base pair changes were discovered in the secondary structure of ITS2. CONCLUSION: These findings corroborate the existence of three cryptic species. Our confirmation of a novel cryptic species complex, initially suggested by DNA barcode lineages, argues for using a multi-marker approach coupled with next-generation sequencing for exploration of other suspected species complexes.


Asunto(s)
Mariposas Diurnas/clasificación , Mariposas Diurnas/genética , Animales , Mariposas Diurnas/microbiología , Núcleo Celular/genética , Costa Rica , ADN Espaciador Ribosómico/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Mitocondrias/genética , Filogenia , Wolbachia/genética
5.
Zookeys ; (383): 1-565, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24624021

RESUMEN

More than half a million specimens of wild-caught Lepidoptera caterpillars have been reared for their parasitoids, identified, and DNA barcoded over a period of 34 years (and ongoing) from Area de Conservación de Guanacaste (ACG), northwestern Costa Rica. This provides the world's best location-based dataset for studying the taxonomy and host relationships of caterpillar parasitoids. Among Hymenoptera, Microgastrinae (Braconidae) is the most diverse and commonly encountered parasitoid subfamily, with many hundreds of species delineated to date, almost all undescribed. Here, we reassess the limits of the genus Apanteles sensu stricto, describe 186 new species from 3,200+ parasitized caterpillars of hundreds of ACG Lepidoptera species, and provide keys to all 205 described Apanteles from Mesoamerica - including 19 previously described species in addition to the new species. The Mesoamerican Apanteles are assigned to 32 species-groups, all but two of which are newly defined. Taxonomic keys are presented in two formats: traditional dichotomous print versions and links to electronic interactive versions (software Lucid 3.5). Numerous illustrations, computer-generated descriptions, distributional information, wasp biology, and DNA barcodes (where available) are presented for every species. All morphological terms are detailed and linked to the Hymenoptera Anatomy Ontology website. DNA barcodes (a standard fragment of the cytochrome c oxidase I (COI) mitochondrial gene), information on wasp biology (host records, solitary/gregariousness of wasp larvae), ratios of morphological features, and wasp microecological distributions were used to help clarify boundaries between morphologically cryptic species within species-complexes. Because of the high accuracy of host identification for about 80% of the wasp species studied, it was possible to analyze host relationships at a regional level. The ACG species of Apanteles attack mainly species of Hesperiidae, Elachistidae and Crambidae (Lepidoptera). About 90% of the wasp species with known host records seem to be monophagous or oligophagous at some level, parasitizing just one host family and commonly, just one species of caterpillar. Only 15 species (9%) parasitize species in more than one family, and some of these cases are likely to be found to be species complexes. We have used several information sources and techniques (traditional taxonomy, molecular, software-based, biology, and geography) to accelerate the process of finding and describing these new species in a hyperdiverse group such as Apanteles. The following new taxonomic and nomenclatural acts are proposed. Four species previously considered to be Apanteles are transferred to other microgastrine genera: Dolichogenidea hedyleptae (Muesebeck, 1958), comb. n., Dolichogenidea politiventris (Muesebeck, 1958), comb. n., Rhygoplitis sanctivincenti (Ashmead, 1900), comb. n., and Illidops scutellaris (Muesebeck, 1921), comb. rev. One European species that is a secondary homonym to a Mesoamerican species is removed from Apanteles and transferred to another genus: Iconella albinervis (Tobias, 1964), stat. rev. The name Apanteles albinervican Shenefelt, 1972, is an invalid replacement name for Apanteles albinervis (Cameron, 1904), stat. rev., and thus the later name is reinstated as valid. The following 186 species, all in Apanteles and all authored by Fernández-Triana, are described as species nova: adelinamoralesae, adrianachavarriae, adrianaguilarae, adrianguadamuzi, aichagirardae, aidalopezae, albanjimenezi, alejandromasisi, alejandromorai, minorcarmonai, alvarougaldei, federicomatarritai, anabellecordobae, rostermoragai, anamarencoae, anamartinesae, anapiedrae, anariasae, andreacalvoae, angelsolisi, arielopezi, bernardoespinozai, bernyapui, bettymarchenae, bienvenidachavarriae, calixtomoragai, carloscastilloi, carlosguadamuzi, eliethcantillanoae, carlosrodriguezi, carlosviquezi, carloszunigai, carolinacanoae, christianzunigai, cinthiabarrantesae, ciriloumanai, cristianalemani, cynthiacorderoae, deifiliadavilae, dickyui, didiguadamuzi, diegoalpizari, diegotorresi, diniamartinezae, duniagarciae, duvalierbricenoi, edgarjimenezi, edithlopezae, eduardoramirezi, edwinapui, eldarayae, erickduartei, esthercentenoae, eugeniaphilipsae, eulogiosequeira, felipechavarriai, felixcarmonai, fernandochavarriai, flormoralesae, franciscopizarroi, franciscoramirezi, freddyquesadai, freddysalazari, gabrielagutierrezae, garygibsoni, gerardobandoi, gerardosandovali, gladysrojasae, glenriverai, gloriasihezarae, guadaluperodriguezae, guillermopereirai, juanmatai, harryramirezi, hectorsolisi, humbertolopezi, inesolisae, irenecarrilloae, isaacbermudezi, isidrochaconi, isidrovillegasi, ivonnetranae, jairomoyai, javiercontrerasi, javierobandoi, javiersihezari, jesusbrenesi, jesusugaldei, jimmychevezi, johanvargasi, jorgecortesi, jorgehernandezi, josecalvoi, josecortesi, josediazi, josejaramilloi, josemonteroi, joseperezi, joserasi, juanapui, juancarrilloi, juangazoi, juanhernandezi, juanlopezi, juanvictori, juliodiazi, juniorlopezi, keineraragoni, laurahuberae, laurenmoralesae, leninguadamuzi, leonelgarayi, lilliammenae, lisabearssae, luciariosae, luisbrizuelai, luiscanalesi, luiscantillanoi, luisgarciai, luisgaritai, luishernandezi, luislopezi, luisvargasi, manuelarayai, manuelpereirai, manuelriosi, manuelzumbadoi, marcobustosi, marcogonzalezi, marcovenicioi, mariachavarriae mariaguevarae, marialuisariasae, mariamendezae, marianopereirai, mariatorrentesae, sigifredomarini, marisolarroyoae, marisolnavarroae, marvinmendozai, mauriciogurdiani, milenagutierrezae, monicachavarriae, oscarchavesi, osvaldoespinozai, pablotranai, pabloumanai, pablovasquezi, paulaixcamparijae, luzmariaromeroae, petronariosae, randallgarciai, randallmartinezi, raulacevedoi, raulsolorsanoi, wadyobandoi, ricardocaleroi, robertmontanoi, robertoespinozai, robertovargasi, rodrigogamezi, rogerblancoi, rolandoramosi, rolandovegai, ronaldcastroi, ronaldgutierrezi, ronaldmurilloi, ronaldnavarroi, ronaldquirosi, ronaldzunigai, rosibelelizondoae, ruthfrancoae, sergiocascantei, sergioriosi, tiboshartae, vannesabrenesae, minornavarroi, victorbarrantesi, waldymedinai, wilbertharayai, williamcamposi, yeissonchavesi, yilbertalvaradoi, yolandarojasae, hazelcambroneroae, zeneidabolanosae.

6.
Neotrop. ichthyol ; 10(2): 349-360, 2012. ilus
Artículo en Inglés | VETINDEX | ID: vti-8753

RESUMEN

The structure and form of gill gland among inseminating and externally fertilizing species of the Cheirodontinae are described under light microscopy, scanning electron microscopy, and transmission electron microscopy, and compared to other members of the family Characidae. At least one species from thirteen cheirodontine genera were analyzed, totaling seventeen species. Gill glands were found in all analyzed mature males of Cheirodontinae and were always absent in females, being located on the anteriormost portion of the lower branch of the first gill arch, extending posteriorly through a variable number of gill filaments. Gill glands of all cheirodontines and of all characid species in which this organ has been described possess the same structure, being considered homologous and supporting a single origin of the structure in a common ancestor to Clade A and Clade B characids.(AU)


A estrutura e forma da glândula branquial de queirodontíneos inseminadores e de fecundação externa são descritas com base em análises de microscopia óptica, microscopia eletrônica de varredura e microscopia eletrônica de transmissão, e comparadas com outros membros da família Characidae. Pelo menos uma espécie de treze gêneros de Cheirodontinae foram analisadas, num total de dezessete espécies. Glândulas branquiais foram encontradas em todos os machos maduros analisados de Cheirodontinae, localizadas na parte mais anterior do ramo inferior do primeiro arco branquial, estendendo-se posteriormente por um número variável de filamentos branquiais, estando sempre ausentes nas fêmeas. As glândulas branquiais de todos os queirodontíneos analisados e de todas as espécies de Characidae em que este órgão foi descrito possuem a mesma estrutura, sendo consideradas homólogas e suportando uma origem única em um ancestral comum aos Clados A e B de Characidae.(AU)


Asunto(s)
Animales , Región Branquial/anatomía & histología , Fertilización/genética , Filogenia , Characiformes/anatomía & histología , Characiformes/crecimiento & desarrollo , Benchmarking/métodos
7.
Neotrop. ichthyol ; 10(2): 349-360, 2012. ilus
Artículo en Inglés | LILACS | ID: lil-640796

RESUMEN

The structure and form of gill gland among inseminating and externally fertilizing species of the Cheirodontinae are described under light microscopy, scanning electron microscopy, and transmission electron microscopy, and compared to other members of the family Characidae. At least one species from thirteen cheirodontine genera were analyzed, totaling seventeen species. Gill glands were found in all analyzed mature males of Cheirodontinae and were always absent in females, being located on the anteriormost portion of the lower branch of the first gill arch, extending posteriorly through a variable number of gill filaments. Gill glands of all cheirodontines and of all characid species in which this organ has been described possess the same structure, being considered homologous and supporting a single origin of the structure in a common ancestor to Clade A and Clade B characids.


A estrutura e forma da glândula branquial de queirodontíneos inseminadores e de fecundação externa são descritas com base em análises de microscopia óptica, microscopia eletrônica de varredura e microscopia eletrônica de transmissão, e comparadas com outros membros da família Characidae. Pelo menos uma espécie de treze gêneros de Cheirodontinae foram analisadas, num total de dezessete espécies. Glândulas branquiais foram encontradas em todos os machos maduros analisados de Cheirodontinae, localizadas na parte mais anterior do ramo inferior do primeiro arco branquial, estendendo-se posteriormente por um número variável de filamentos branquiais, estando sempre ausentes nas fêmeas. As glândulas branquiais de todos os queirodontíneos analisados e de todas as espécies de Characidae em que este órgão foi descrito possuem a mesma estrutura, sendo consideradas homólogas e suportando uma origem única em um ancestral comum aos Clados A e B de Characidae.


Asunto(s)
Animales , Characiformes/anatomía & histología , Fertilización/genética , Filogenia , Región Branquial/anatomía & histología , Benchmarking/métodos , Characiformes/crecimiento & desarrollo
8.
PLoS One ; 6(8): e19874, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21857895

RESUMEN

BACKGROUND: An intense, 30-year, ongoing biodiversity inventory of Lepidoptera, together with their food plants and parasitoids, is centered on the rearing of wild-caught caterpillars in the 120,000 terrestrial hectares of dry, rain, and cloud forest of Area de Conservacion Guanacaste (ACG) in northwestern Costa Rica. Since 2003, DNA barcoding of all species has aided their identification and discovery. We summarize the process and results for a large set of the species of two speciose subfamilies of ACG skipper butterflies (Hesperiidae) and emphasize the effectiveness of barcoding these species (which are often difficult and time-consuming to identify). METHODOLOGY/PRINCIPAL FINDINGS: Adults are DNA barcoded by the Biodiversity Institute of Ontario, Guelph, Canada; and they are identified by correlating the resulting COI barcode information with more traditional information such as food plant, facies, genitalia, microlocation within ACG, caterpillar traits, etc. This process has found about 303 morphologically defined species of eudamine and pyrgine Hesperiidae breeding in ACG (about 25% of the ACG butterfly fauna) and another 44 units indicated by distinct barcodes (n = 9,094), which may be additional species and therefore may represent as much as a 13% increase. All but the members of one complex can be identified by their DNA barcodes. CONCLUSIONS/SIGNIFICANCE: Addition of DNA barcoding to the methodology greatly improved the inventory, both through faster (hence cheaper) accurate identification of the species that are distinguishable without barcoding, as well as those that require it, and through the revelation of species "hidden" within what have long been viewed as single species. Barcoding increased the recognition of species-level specialization. It would be no more appropriate to ignore barcode data in a species inventory than it would be to ignore adult genitalia variation or caterpillar ecology.


Asunto(s)
Mariposas Diurnas/clasificación , Mariposas Diurnas/genética , Código de Barras del ADN Taxonómico/métodos , Filogenia , Alimentación Animal , Animales , Biodiversidad , Cruzamiento , Mariposas Diurnas/crecimiento & desarrollo , Costa Rica , Ecología , Complejo IV de Transporte de Electrones/genética , Femenino , Variación Genética , Geografía , Masculino , Desarrollo de la Planta , Plantas/parasitología , Especificidad de la Especie , Clima Tropical
9.
Neotrop. ichthyol ; 9(4): 881-888, 2011. ilus
Artículo en Inglés | VETINDEX | ID: vti-5640

RESUMEN

This study presents details of sperm ultrastructure for Gymnotus aff. carapo (Gymnotidae), Eigenmannia trilineata (Sternopygidae), and three Brachyhypopomus species (B. draco, B. bombilla, and B. gauderio - Hypopomidae) from southern Brazil. Differences were found among the representatives of the different families. For example, nuclear rotation was present in E. trilineata and in the Brachyhypopomus species, but absent in Gymnotus aff. carapo, and the presence of flagellar fins was only observed in E. trilineata. Some intraspecific variations could also be noticed among the Brachyhypopomus species analyzed. Most of the characters found in the spermatozoa of the species studied herein are shared with species of Gymnotiformes previously analyzed.(AU)


Este estudo apresenta detalhes sobre a ultraestrutura do espermatozoide de Gymnotus aff. carapo (Gymnotidae), Eigenmannia trilineata (Sternopygidae), e três espécies de Brachyhypopomus (B. draco, B. bombilla, e B. gauderio - Hypopomidae) do sul do Brasil. Diferenças foram encontradas entre os representantes das diferentes famílias, como por exemplo a presença de rotação nuclear em E. trilineata e nas espécies de Brachyhypopomus e a ausência em G. aff. carapo, e a presença de aletas laterais no flagelo observada somente em E. trilineata. Algumas variações intraespecíficas também puderam ser registradas entre as espécies de Brachyhypopomus analisadas. A maioria das características encontradas nos espermatozoides das espécies aqui analisadas são compartilhadas com as demais espécies de Gymnotifomes previamente analisadas.(AU)


Asunto(s)
Animales , Peces , Gymnotiformes/genética
10.
Neotrop. ichthyol ; 9(4): 881-888, 2011. ilus
Artículo en Inglés | LILACS | ID: lil-611029

RESUMEN

This study presents details of sperm ultrastructure for Gymnotus aff. carapo (Gymnotidae), Eigenmannia trilineata (Sternopygidae), and three Brachyhypopomus species (B. draco, B. bombilla, and B. gauderio - Hypopomidae) from southern Brazil. Differences were found among the representatives of the different families. For example, nuclear rotation was present in E. trilineata and in the Brachyhypopomus species, but absent in Gymnotus aff. carapo, and the presence of flagellar fins was only observed in E. trilineata. Some intraspecific variations could also be noticed among the Brachyhypopomus species analyzed. Most of the characters found in the spermatozoa of the species studied herein are shared with species of Gymnotiformes previously analyzed.


Este estudo apresenta detalhes sobre a ultraestrutura do espermatozoide de Gymnotus aff. carapo (Gymnotidae), Eigenmannia trilineata (Sternopygidae), e três espécies de Brachyhypopomus (B. draco, B. bombilla, e B. gauderio - Hypopomidae) do sul do Brasil. Diferenças foram encontradas entre os representantes das diferentes famílias, como por exemplo a presença de rotação nuclear em E. trilineata e nas espécies de Brachyhypopomus e a ausência em G. aff. carapo, e a presença de aletas laterais no flagelo observada somente em E. trilineata. Algumas variações intraespecíficas também puderam ser registradas entre as espécies de Brachyhypopomus analisadas. A maioria das características encontradas nos espermatozoides das espécies aqui analisadas são compartilhadas com as demais espécies de Gymnotifomes previamente analisadas.


Asunto(s)
Animales , Peces , Gymnotiformes/genética
11.
Proc Natl Acad Sci U S A ; 107(26): 11659-65, 2010 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-20547863

RESUMEN

We propose that the many different, but essentially similar, eye-like and face-like color patterns displayed by hundreds of species of tropical caterpillars and pupae-26 examples of which are displayed here from the dry, cloud, and rain forests of Area de Conservacion Guanacaste (ACG) in northwestern Costa Rica-constitute a huge and pervasive mimicry complex that is evolutionarily generated and sustained by the survival behavior of a large and multispecific array of potential predators: the insect-eating birds. We propose that these predators are variously and innately programmed to flee when abruptly confronted, at close range, with what appears to be an eye of one of their predators. Such a mimetic complex differs from various classical Batesian and Müllerian mimicry complexes of adult butterflies in that (i) the predators sustain it for the most part by innate traits rather than by avoidance behavior learned through disagreeable experiences, (ii) the more or less harmless, sessile, and largely edible mimics vastly outnumber the models, and (iii) there is no particular selection for the eye-like color pattern to closely mimic the eye or face of any particular predator of the insect-eating birds or that of any other member of this mimicry complex. Indeed, selection may not favor exact resemblance among these mimics at all. Such convergence through selection could create a superabundance of one particular false eyespot or face pattern, thereby increasing the likelihood of a bird species or guild learning to associate that pattern with harmless prey.


Asunto(s)
Lepidópteros/anatomía & histología , Lepidópteros/genética , Pigmentación/genética , Animales , Evolución Biológica , Aves/fisiología , Tipificación del Cuerpo , Costa Rica , Dieta , Ojo/anatomía & histología , Lepidópteros/crecimiento & desarrollo , Modelos Biológicos , Conducta Predatoria , Pupa/anatomía & histología , Selección Genética , Clima Tropical
12.
Neotrop. ichthyol ; 8(1): 87-96, Jan.-Mar. 2010. tab, ilus
Artículo en Inglés | VETINDEX | ID: vti-2749

RESUMEN

The reproductive biology and development of the gill gland are described for Macropsobrycon uruguayanae, an inseminating characid species of the tribe Compsurini, subfamily Cheirodontinae. Between April 2001 and March 2002, 117 males and 143 females of this species were collected in the rio Ibicuí, Uruguay basin in the State of Rio Grande do Sul, Brazil. Reproductively active individuals were present during most months sampled, indicating lack of a well-defined seasonal reproductive period. Several maturing females were found to be inseminated before completing full maturation. Histological analyses demonstrated spermatozoa within the ovaries of females in different stages of gonadal maturation collected during most months. No immature females had inseminated ovaries. Standard length at first gonadal maturation was estimated to be 24 mm for both males and females. Mean absolute fecundity was 191.08 (± 48.83 SD) oocytes per female, one of the lowest among characids. Relative fecundity was 0.539 (± 0.069 SD) oocytes per mg weight of the female, a value similar to that found for the majority of species of Cheirodontinae. The presence of two cohorts of oocytes within ovaries of M. uruguayanae indicates synchronous development, with total spawning. The mean diameter of mature oocytes was 0.6711 (± 0.1252 SD) mm, smaller than that found for the majority of species of Characidae. Gill glands occurred in all mature males, as well as in males undergoing advanced maturation. In the latter case, fewer gill filaments comprised the glands. Gill glands were not observed in immature males, males undergoing the initial stages of maturation, or in any female. A given gill gland may comprise as many as 24 filaments of the lateral hemibranch of the first gill arch. Secondary lamellae within most of the gill gland are greatly reduced, with columnar cells being present between them. These columnar cells contain abundant vesicles, suggesting secretory activity. ...(AU)


São descritos a biologia reprodutiva e o desenvolvimento da glândula branquial de Macropsobrycon uruguayanae, uma espécie de caracídeo inseminador da tribo Compsurini, subfamília Cheirodontinae. Foram capturados 117 machos e 143 fêmeas da espécie entre abril de 2001 e março de 2002 no rio Ibicuí, bacia do rio Uruguay no Estado do Rio Grande do Sul, Brasil. Indivíduos em reprodução foram observados na maioria dos meses amostrados, não havendo período reprodutivo sazonalmente definido. Fêmeas em maturação apresentavam-se inseminadas antes de completar a maturação plena. Análises histológicas mostraram espermatozoides nos ovários de fêmeas em diferentes estádios de maturação gonadal coletadas na maioria dos meses. Nenhuma fêmea imatura apresentou ovários inseminados. O tamanho de primeira maturação gonadal foi estimado em 24 mm de comprimento padrão para machos e fêmeas. A fecundidade absoluta média foi de 191,08 (± 48,83 SD) ovócitos por fêmea, uma das mais baixas entre caracídeos. A fecundidade relativa foi de 0,539 (± 0,069 SD) ovócitos por mg do peso da fêmea, valor semelhante ao encontrado para a maioria das espécies de Cheirodontinae. A espécie mostrou desenvolvimento ovocitário do tipo sincrônico em dois grupos, indicando desova total. O diâmetro médio dos ovócitos maduros foi de 0,6711 (± 0,1252 SD) mm, menor do que o encontrado para a maioria das espécies de Characidae. A glândula branquial ocorreu em todos os machos maduros analisados, sendo também observada em machos em maturação avançada, porém envolvendo um número menor de filamentos branquiais. A glândula branquial não foi observada em machos em maturação inicial ou imaturos e em fêmeas em qualquer fase de maturação. Esta glândula pode compreender até 24 filamentos da hemibrânquia externa do primeiro arco. As lamelas secundárias da glândula branquial são reduzidas e há proliferação de células secretoras colunares entre elas. Estas células são preenchidas por inúmeros vacúolos, ...(AU)


Asunto(s)
Animales , Peces , Desarrollo Sexual , Caracteres Sexuales , Fertilidad
13.
Neotrop. ichthyol ; 8(1): 87-96, Jan.-Mar. 2010. tab, ilus
Artículo en Inglés | LILACS | ID: lil-551171

RESUMEN

The reproductive biology and development of the gill gland are described for Macropsobrycon uruguayanae, an inseminating characid species of the tribe Compsurini, subfamily Cheirodontinae. Between April 2001 and March 2002, 117 males and 143 females of this species were collected in the rio Ibicuí, Uruguay basin in the State of Rio Grande do Sul, Brazil. Reproductively active individuals were present during most months sampled, indicating lack of a well-defined seasonal reproductive period. Several maturing females were found to be inseminated before completing full maturation. Histological analyses demonstrated spermatozoa within the ovaries of females in different stages of gonadal maturation collected during most months. No immature females had inseminated ovaries. Standard length at first gonadal maturation was estimated to be 24 mm for both males and females. Mean absolute fecundity was 191.08 (± 48.83 SD) oocytes per female, one of the lowest among characids. Relative fecundity was 0.539 (± 0.069 SD) oocytes per mg weight of the female, a value similar to that found for the majority of species of Cheirodontinae. The presence of two cohorts of oocytes within ovaries of M. uruguayanae indicates synchronous development, with total spawning. The mean diameter of mature oocytes was 0.6711 (± 0.1252 SD) mm, smaller than that found for the majority of species of Characidae. Gill glands occurred in all mature males, as well as in males undergoing advanced maturation. In the latter case, fewer gill filaments comprised the glands. Gill glands were not observed in immature males, males undergoing the initial stages of maturation, or in any female. A given gill gland may comprise as many as 24 filaments of the lateral hemibranch of the first gill arch. Secondary lamellae within most of the gill gland are greatly reduced, with columnar cells being present between them. These columnar cells contain abundant vesicles, suggesting secretory activity. ...


São descritos a biologia reprodutiva e o desenvolvimento da glândula branquial de Macropsobrycon uruguayanae, uma espécie de caracídeo inseminador da tribo Compsurini, subfamília Cheirodontinae. Foram capturados 117 machos e 143 fêmeas da espécie entre abril de 2001 e março de 2002 no rio Ibicuí, bacia do rio Uruguay no Estado do Rio Grande do Sul, Brasil. Indivíduos em reprodução foram observados na maioria dos meses amostrados, não havendo período reprodutivo sazonalmente definido. Fêmeas em maturação apresentavam-se inseminadas antes de completar a maturação plena. Análises histológicas mostraram espermatozoides nos ovários de fêmeas em diferentes estádios de maturação gonadal coletadas na maioria dos meses. Nenhuma fêmea imatura apresentou ovários inseminados. O tamanho de primeira maturação gonadal foi estimado em 24 mm de comprimento padrão para machos e fêmeas. A fecundidade absoluta média foi de 191,08 (± 48,83 SD) ovócitos por fêmea, uma das mais baixas entre caracídeos. A fecundidade relativa foi de 0,539 (± 0,069 SD) ovócitos por mg do peso da fêmea, valor semelhante ao encontrado para a maioria das espécies de Cheirodontinae. A espécie mostrou desenvolvimento ovocitário do tipo sincrônico em dois grupos, indicando desova total. O diâmetro médio dos ovócitos maduros foi de 0,6711 (± 0,1252 SD) mm, menor do que o encontrado para a maioria das espécies de Characidae. A glândula branquial ocorreu em todos os machos maduros analisados, sendo também observada em machos em maturação avançada, porém envolvendo um número menor de filamentos branquiais. A glândula branquial não foi observada em machos em maturação inicial ou imaturos e em fêmeas em qualquer fase de maturação. Esta glândula pode compreender até 24 filamentos da hemibrânquia externa do primeiro arco. As lamelas secundárias da glândula branquial são reduzidas e há proliferação de células secretoras colunares entre elas. Estas células são preenchidas por inúmeros vacúolos, ...


Asunto(s)
Animales , Peces , Caracteres Sexuales , Desarrollo Sexual , Fertilidad
14.
Clinics (Sao Paulo) ; 65(11): 1189-95, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21243295

RESUMEN

INTRODUCTION: Investigation of resuscitation fluids in our swine hemorrhage model revealed moderate to severe chronic pneumonia in five swine at necropsy. Our veterinary staff suggested that we perform a retrospective analysis of prospectively collected data from these animals. We compared the data to that of ten healthy swine to determine the physiologic consequences of the added stress on our hemorrhage/resuscitation model. METHODS: Anesthetized, immature female swine (40 ± 5 kg) were instrumented for determining arterial and venous pressures, cardiac output and urine production. A controlled hemorrhage of 20 ml/kg over 4 min 40 sec was followed at 30 min by a second hemorrhage of 8 ml/kg and resuscitation with 1.5 ml/kg/min of LR solutions to achieve and maintain systolic blood pressure at 80 ± 5 mmHg for 3.5 hrs. Chemistries and arterial and venous blood gasses were determined from periodic blood samples along with hemodynamic variables. RESULTS: There were significant decreases in survival, urine output, cardiac output and oxygen delivery at 60 min and O2 consumption at 120 min in the pneumonia group compared to the non-pneumonia group. There were no differences in other metabolic or hemodynamic data between the groups. CONCLUSION: Although pneumonia had little influence on pulmonary gas exchange, it influenced cardiac output, urine output and survival compared to healthy swine, suggesting a decrease in the physiologic reserve. These data may be relevant to patients with subclinical infection who are stressed by hemorrhage and may explain in part why some similarly injured patients require more resuscitation efforts than others.


Asunto(s)
Enfermedades Asintomáticas , Hemorragia/fisiopatología , Neumonía/fisiopatología , Resucitación/métodos , Animales , Presión Sanguínea/fisiología , Gasto Cardíaco/fisiología , Modelos Animales de Enfermedad , Femenino , Consumo de Oxígeno/fisiología , Estudios Retrospectivos , Tasa de Supervivencia , Porcinos , Factores de Tiempo , Orina
15.
Clinics ; Clinics;65(11): 1189-1195, 2010. graf, tab
Artículo en Inglés | LILACS | ID: lil-571444

RESUMEN

INTRODUCTION: Investigation of resuscitation fluids in our swine hemorrhage model revealed moderate to severe chronic pneumonia in five swine at necropsy. Our veterinary staff suggested that we perform a retrospective analysis of prospectively collected data from these animals. We compared the data to that of ten healthy swine to determine the physiologic consequences of the added stress on our hemorrhage/resuscitation model. METHODS: Anesthetized, immature female swine (40 ± 5 kg) were instrumented for determining arterial and venous pressures, cardiac output and urine production. A controlled hemorrhage of 20 ml/kg over 4 min 40 sec was followed at 30 min by a second hemorrhage of 8 ml/kg and resuscitation with 1.5 ml/kg/min of LR solutions to achieve and maintain systolic blood pressure at 80 ± 5 mmHg for 3.5 hrs. Chemistries and arterial and venous blood gasses were determined from periodic blood samples along with hemodynamic variables. RESULTS: There were significant decreases in survival, urine output, cardiac output and oxygen delivery at 60 min and O2 consumption at 120 min in the pneumonia group compared to the non-pneumonia group. There were no differences in other metabolic or hemodynamic data between the groups. CONCLUSION: Although pneumonia had little influence on pulmonary gas exchange, it influenced cardiac output, urine output and survival compared to healthy swine, suggesting a decrease in the physiologic reserve. These data may be relevant to patients with subclinical infection who are stressed by hemorrhage and may explain in part why some similarly injured patients require more resuscitation efforts than others.


Asunto(s)
Animales , Femenino , Enfermedades Asintomáticas , Hemorragia/fisiopatología , Neumonía/fisiopatología , Resucitación/métodos , Presión Sanguínea/fisiología , Gasto Cardíaco/fisiología , Modelos Animales de Enfermedad , Consumo de Oxígeno/fisiología , Estudios Retrospectivos , Tasa de Supervivencia , Porcinos , Factores de Tiempo , Orina
16.
Proc Natl Acad Sci U S A ; 105(17): 6350-5, 2008 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-18436645

RESUMEN

DNA barcodes can be used to identify cryptic species of skipper butterflies previously detected by classic taxonomic methods and to provide first clues to the existence of yet other cryptic species. A striking case is the common geographically and ecologically widespread neotropical skipper butterfly Perichares philetes (Lepidoptera, Hesperiidae), described in 1775, which barcoding splits into a complex of four species in Area de Conservación Guanacaste (ACG) in northwestern Costa Rica. Three of the species are new, and all four are described. Caterpillars, pupae, and foodplants offer better distinguishing characters than do adults, whose differences are mostly average, subtle, and blurred by intraspecific variation. The caterpillars of two species are generalist grass-eaters; of the other two, specialist palm-eaters, each of which feeds on different genera. But all of these cryptic species are more specialized in their diet than was the morphospecies that held them. The four ACG taxa discovered to date belong to a panneotropical complex of at least eight species. This complex likely includes still more species, whose exposure may require barcoding. Barcoding ACG hesperiid morphospecies has increased their number by nearly 10%, an unexpectedly high figure for such relatively well known insects.


Asunto(s)
Mariposas Diurnas/genética , ADN/metabolismo , Animales , Costa Rica , Femenino , Larva , Masculino , Filogenia , Pupa , Especificidad de la Especie
17.
J Morphol ; 269(6): 691-7, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18302242

RESUMEN

Macropsobrycon uruguayanae is a small, inseminating characid (tetra) of the tribe Compsurini. Although spermatozoa can be found within the ovarian cavity close to oocytes, the exact moment of fertilization has not yet been determined. Spermatozoa have moderately elongate nuclei with electron-dense chromatin. During spermiogenesis, nuclear rotation takes place. Elongate mitochondria with lamellar cristae are found posterior to the nucleus. Centrioles are parallel to one another with the proximal centriole slightly anterior to the longer distal one. The anterior tip of the proximal centriole is located within a shallow nuclear fossa. Electron-dense spurs are associated within the anterior and posterior ends of the distal centriole. Striated centriolar rootlets radiate both anteriorly and posteriorly from the distal centriole. Nine longitudinal accessory microtubules surround the axoneme in the proximal flagellum. The flagellum has a typical 9 + 2 axoneme with no intratubular differentiation. Atypical spermatozoa are also found in the testicular lumen. These cells resemble spermatozoa in most aspects, except that their nuclei are variable in shape, with the granular chromatin less electron-dense than that seen in spermatozoa. The origin and function of these cells could not be determined. The specializations seen in the spermatozoa are discussed as possible adaptations related to the habit of insemination.


Asunto(s)
Peces/anatomía & histología , Inseminación , Espermatozoides/ultraestructura , Animales , Femenino , Peces/fisiología , Masculino
18.
Neotrop. ichthyol ; 5(4): 457-470, Oct.-Dec. 2007. ilus
Artículo en Inglés | VETINDEX | ID: vti-1774

RESUMEN

Spermiogenesis and sperm ultrastructure were analyzed in two species of characids with different modes of fertilization: externally fertilizing Hemigrammus erythrozonus and inseminating Corynopoma riisei. Spermiogenesis in H. erythrozonus is characterized by lateral development of the flagellum, nuclear rotation, formation of a shallow nuclear fossa, condensation of the chromatin by elimination of the electron-lucent area from the peripheral region of the nucleus, and renewal of the nuclear membrane. Multilammelated membrane and multivesicular bodies were also observed during elimination of the excess cytoplasm. The spermatozoon exhibits characters typical of "aquasperm," i.e. a spherical head containing a spherical nucleus with highly condensed chromatin, several small mitochondria located at the base of the nucleus within a cytoplasmic collar that extends into a long cytoplasmic sleeve surrounding the anterior part of the single flagellum, which is contained within a cytoplasmic canal. The flagellum lacks fins. The proximal and distal centrioles are nearly parallel to one another, with the anterior tips of both located within shallow nuclear fossae. Spermiogenesis in C. riisei is characterized by nuclear elongation alongside the forming flagellum, formation of an elongate cytoplasmic canal, displacement and elongation of the mitochondria, and uniform condensation of chromatin throughout the nucleus through enlargement of the diameter of the chromatin granules. The spermatozoon has an elongate nucleus with two elongate mitochondria localized to one side. Mitochondria are also located posterior to the nucleus forming a mitochondrial region. The single flagellum, which lacks fins, is lateral to the nucleus and initially contained within the greatly elongate cytoplasmic canal before exiting the canal at its posterior terminus. The spermatozoon of C. riisei exhibits several characters typical of "introsperm," such as an elongate nucleus...(AU)


Foram analisadas a espermiogênese e ultraestrutura dos espermatozóides de dois caracídeos com modos de fertilização distintos: fertilização externa em Hemigrammus erythrozonus e inseminação em Corynopoma riisei. A espermiogênese em H. erythrozonus é caracterizada pelo desenvolvimento lateral do flagelo, rotação nuclear, formação de uma fossa nuclear rasa, condensação de cromatina por eliminação da área elétron-lúcida na região periférica do núcleo e renovação da membrana nuclear. Membrana multilamelada e corpos multivesiculares foram observados durante a eliminação do excesso de citoplasma. O espermatozóide exibe os caracteres típicos do "aquaespermatozóide," com uma cabeça esférica que contem um núcleo esférico com cromatina muito condensada, várias mitocôndrias pequenas localizadas na base do núcleo e dentro de um colar citoplasmático, extedendo-se em uma bainha citoplasmática longa que rodeia a parte anterior do único flagelo, que está contido dentro de um canal citoplasmático. O flagelo carece de aletas. Os centríolos proximais e distais são quase paralelos, com as partes anteriores dos dois localizadas dentro de fossas nucleares pouco profundas. A espermiogênese em C. riisei é caracterizada pelo alongamento nuclear ao longo do flagelo, a formação de um canal citoplasmático longo, deslocamento e alongamento das mitocôndrias e uma condensação uniforme da cromatina por todo o núcleo por meio do aumento do diâmetro dos grânulos de cromatina. O espermatozóide tem um núcleo alongado com duas mitocôndrias alongadas dispostas em um lado. Algumas mitocôndrias localizam-se posteriormente ao núcleo formando uma região mitocondrial. O único flagelo, que carece de aletas, é lateral ao núcleo, posicionado anteriormente dentro de um canal citoplasmático muito alongado. O espermatozóide de C. riisei exibe vários caracteres típicos de "introespermatozóides" tais como um núcleo alongado e parte média alongada (região mitocondrial). A cromatina nuclear...(AU)


Asunto(s)
Animales , Espermatogénesis/fisiología , Peces/genética , Espermatozoides/citología , Cromatina/fisiología , Fertilización/fisiología
19.
Neotrop. ichthyol ; 5(4): 457-470, Oct.-Dec. 2007. ilus
Artículo en Inglés | LILACS | ID: lil-471977

RESUMEN

Spermiogenesis and sperm ultrastructure were analyzed in two species of characids with different modes of fertilization: externally fertilizing Hemigrammus erythrozonus and inseminating Corynopoma riisei. Spermiogenesis in H. erythrozonus is characterized by lateral development of the flagellum, nuclear rotation, formation of a shallow nuclear fossa, condensation of the chromatin by elimination of the electron-lucent area from the peripheral region of the nucleus, and renewal of the nuclear membrane. Multilammelated membrane and multivesicular bodies were also observed during elimination of the excess cytoplasm. The spermatozoon exhibits characters typical of "aquasperm," i.e. a spherical head containing a spherical nucleus with highly condensed chromatin, several small mitochondria located at the base of the nucleus within a cytoplasmic collar that extends into a long cytoplasmic sleeve surrounding the anterior part of the single flagellum, which is contained within a cytoplasmic canal. The flagellum lacks fins. The proximal and distal centrioles are nearly parallel to one another, with the anterior tips of both located within shallow nuclear fossae. Spermiogenesis in C. riisei is characterized by nuclear elongation alongside the forming flagellum, formation of an elongate cytoplasmic canal, displacement and elongation of the mitochondria, and uniform condensation of chromatin throughout the nucleus through enlargement of the diameter of the chromatin granules. The spermatozoon has an elongate nucleus with two elongate mitochondria localized to one side. Mitochondria are also located posterior to the nucleus forming a mitochondrial region. The single flagellum, which lacks fins, is lateral to the nucleus and initially contained within the greatly elongate cytoplasmic canal before exiting the canal at its posterior terminus. The spermatozoon of C. riisei exhibits several characters typical of "introsperm," such as an elongate nucleus...


Foram analisadas a espermiogênese e ultraestrutura dos espermatozóides de dois caracídeos com modos de fertilização distintos: fertilização externa em Hemigrammus erythrozonus e inseminação em Corynopoma riisei. A espermiogênese em H. erythrozonus é caracterizada pelo desenvolvimento lateral do flagelo, rotação nuclear, formação de uma fossa nuclear rasa, condensação de cromatina por eliminação da área elétron-lúcida na região periférica do núcleo e renovação da membrana nuclear. Membrana multilamelada e corpos multivesiculares foram observados durante a eliminação do excesso de citoplasma. O espermatozóide exibe os caracteres típicos do "aquaespermatozóide," com uma cabeça esférica que contem um núcleo esférico com cromatina muito condensada, várias mitocôndrias pequenas localizadas na base do núcleo e dentro de um colar citoplasmático, extedendo-se em uma bainha citoplasmática longa que rodeia a parte anterior do único flagelo, que está contido dentro de um canal citoplasmático. O flagelo carece de aletas. Os centríolos proximais e distais são quase paralelos, com as partes anteriores dos dois localizadas dentro de fossas nucleares pouco profundas. A espermiogênese em C. riisei é caracterizada pelo alongamento nuclear ao longo do flagelo, a formação de um canal citoplasmático longo, deslocamento e alongamento das mitocôndrias e uma condensação uniforme da cromatina por todo o núcleo por meio do aumento do diâmetro dos grânulos de cromatina. O espermatozóide tem um núcleo alongado com duas mitocôndrias alongadas dispostas em um lado. Algumas mitocôndrias localizam-se posteriormente ao núcleo formando uma região mitocondrial. O único flagelo, que carece de aletas, é lateral ao núcleo, posicionado anteriormente dentro de um canal citoplasmático muito alongado. O espermatozóide de C. riisei exibe vários caracteres típicos de "introespermatozóides" tais como um núcleo alongado e parte média alongada (região mitocondrial). A cromatina nuclear...


Asunto(s)
Animales , Cromatina/fisiología , Espermatogénesis/fisiología , Espermatozoides/citología , Fertilización/fisiología , Peces/genética
20.
J Morphol ; 268(1): 23-32, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17146774

RESUMEN

Light and electron microscopy were used to investigate the morphology of reproductive characters in a characid fish, Brittanichthys axelrodi. Spermatozoa were found in ovaries of females, thereby confirming insemination in this species. Bony hooks can be found on the fourth unbranched ray and branched rays 1-4 of the anal fin and the unique sigmoidally-curved ray of the caudal fin in mature males. Testes have three distinct regions: an anterior spermatogenic region, an aspermatogenic middle region lined with a simple squamous epithelium and used for storage of mature spermatozoa, and a posterior region of coiled chambers lined with a high simple cuboidal epithelium. The most posterior region appears to be instrumental in the formation and storage of spermatozeugmata, unencapsulated sperm packets. Thus far, this tripartite testis morphology is unique among characids. The mature spermatozoon has an elongate nucleus ( approximately 5 microm in length). A striated rootlet originates at the anterior end of the distal centriole and continues to the anterior tip of the cell. The striated rootlet wraps around the entire ventral area of the anterior part of the nucleus and appears to continue around the anterior tip of the nucleus and down the dorsal side as electron-dense material. Several large, spherical mitochondria ( approximately 0.6 microm in diameter) with lamellar cristae overlap the posterior end of the nucleus and continue beyond together with the cytoplasmic collar that contains the flagellum which lacks axonemal fins. Each spermatozeugma is lanceolate in shape when sectioned mid-sagitally, with the core staining positively for mucopolysaccharides. In both sexes, the gonopore opens posterior to the anus, with the urinary pore having a separate opening posterior to the gonopore. Bands of skeletal muscle were found in the area of the male gonopore. These morphological features are likely linked to the reproductive mode of insemination, a trait that is so far as known, relatively rare among teleost fishes, but is proving increasingly frequent among certain groups of characid fishes.


Asunto(s)
Peces/anatomía & histología , Inseminación/fisiología , Ovario/ultraestructura , Reproducción/fisiología , Testículo/ultraestructura , Animales , Núcleo Celular/fisiología , Núcleo Celular/ultraestructura , Femenino , Peces/fisiología , Genitales Femeninos/fisiología , Genitales Femeninos/ultraestructura , Genitales Masculinos/fisiología , Genitales Masculinos/ultraestructura , Masculino , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Mitocondrias/fisiología , Mitocondrias/ultraestructura , Ovario/fisiología , Caracteres Sexuales , América del Sur , Espermatozoides/fisiología , Espermatozoides/ultraestructura , Testículo/fisiología
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