RESUMO: O gato-palheiro Leopardus colocolo (Molina, 1782) é uma espécie da família Felidae, com ampla distribuição na América do Sul. Está incluido no Appendix II da CITES e classificada como Próxima da Extinção na Lista Vermelha da IUCN, apresentando população em decrescimo. Com base nessas informações o objetivo deste estudo é caracterizar morfologicamente os testículos e ductos epididimários de L. colocolo. O animal, oriundo do Zoológico da Universidade Federal de Mato Grosso, Brasil, veio a óbito após procedimento anestésico e o sistema reprodutor masculino foi dissecado para coleta dos testículos. As amostras retiradas foram fragmentadas e histologicamente examinadas. A partir das análises microscópicas dos testículos foram identificados: a túnica vaginal e albugínea, formada por tecido conjuntivo denso modelado, com grande quantidade de fibras de colágeno. A túnica albugínea emite septos fibrosos para o interior do órgão. Os túbulos seminíferos são enovelados e revestidos internamente por epitélio estratificado constituído por células espermatogênicas e células somáticas de Sertoli, envolvidos por uma membrana basal com presença de células mioides. O tecido intersticial, entre os túbulos seminíferos, é constituído de tecido conjuntivo do tipo frouxo com vasos sanguíneos e linfáticos, e células de Leydig em formato poliédrico. Os ductos epididimários apresentaram epitélio cilíndrico pseudoestratificado com células secretoras dos quais projetam estereocílios, situados sobre uma membrana basal repleta por células mióides. Este epitélio apresenta células principais e basais, cujas células principais projetam estereocílios em direção ao lúmen do ducto epididimário.

ABSTRACT: The pampas cat Leopardus colocolo (Molina, 1782) is a species of the Felidae family, widely distributed in South America, included on CITES Appendix II and classified as Near Threatened on the IUCN Red List, with population trend decreasing. Based on this information, the objective of this study is to describe morphologically the testes and epididymal ducts of pampas cat. The animal, coming from the Federal University of Mato Grosso Zoo, Brazil, had died after anesthesia procedure and the male reproductive system was dissected to collect the testicles. The samples taken were fragmented and histologically examined. From the microscopic analysis of the testes were identified: vaginal and tunica albuginea, formed by dense connective tissue modeled with large amount of collagen fibers. The tunica albuginea fibrous septa emits into the body. The seminiferous tubules are coiled and coated internally by spermatogenic epithelium consisting of Sertoli cells, surrounded by a basement membrane in the presence of myoid cells. The interstitial tissue between the seminiferous tubules, is composed of loose connective tissue, blood and lymph vessels, and Leydig cells in polyhedral shape. The epididymal ducts showed pseudostratified columnar epithelium with secretory cells of which stereocilia design, situated on a basement membrane filled by myoid cells. This epithelium has principal and basal cells, the main cell design stereocilia toward the lumen of the epididymal duct.

A compreensão do ciclo reprodutivo possibilita entender quais são as mudanças morfológicas que se desenvolvem na gônada neste período. Assim, muitos estudos têm sido realizados no intuito de descrever e classificar as fases de desenvolvimento gonadal e dos estados reprodutivos dos peixes da região Neotropical. Com esse objetivo foram coletados espécimes de Melanorivulusaff. punctatus em um represamento permanente em Chapada dos Guimarães, Mato Grosso, Brasil. As gônadas foram preparadas para análise à microscopia de luz. A ovogênese e a espermatogênese foram descritas e caracterizados os estágios de desenvolvimento gonadal, juntamente com as avaliações de razão gonadossomática, contagem de células germinativas e verificação de variação de ovócitos maduros em fêmeas. Durante todo o ano as gônadas masculinas apresentaram-se como aptas a reprodução, caracterizadas pela presença de espermatogônias indiferenciadas e diferenciadas, espermatócitos organizados em cistos, espermátides em cistos com parede mais espessa e espermatozoides livres no lúmen e no ducto. Isso pode indicar um ciclo reprodutivo contínuo com espermiação parcelada. As fêmeas apresentaram gônadas em estágio de desenvolvimento de maio a setembro, com ovogônias indiferenciadas e diferenciadas e ovócitos iniciais sempre voltados para o lúmen, ovócitos pré-vitelogênicos e vitelogênicos abundantes e algumas atresias. Na fase de apto a desova, observada de outubro a março, os ovócitos maduros são abundantes, há muitos complexos pós ovulatórios e algumas atresias em estágio avançado. A fase de regressão, constatada em alguns indivíduos de fevereiro a abril, é caracterizada por ovários com muitas atresias e complexos pós-ovulatórios. Os mesmos resultados foram encontrados nas avaliações quantitativas realizadas. Logo, pode-se caracterizar o ciclo como descontínuo com desova parcelada. Assim, o ciclo reprodutivo desta espécie pode ser caracterizado como contínuo para machos e descontínuo para fêmeas, que apresentam uma fase mais intensa de reprodução de outubro a março. Porém, ambos possuem liberação de gametas parcelada.

The comprehension of the reproductive cycle allows to understand which are the morphological changes that develop in the gonad during this interval. Thus, many studies have been undertaken in order to describe and classify the stages of gonadal development and reproductive status of Neotropical fishes. For this purpose, specimens of Melanorivulusaff. punctatus were collected in a permanent dam in Chapada dos Guimarães, Mato Grosso, Brazil. The gonads were prepared for analysis by light microscopy. The oogenesis and spermatogenesis have been described, characterizing the stages of gonadal development, together with assessments of the gonadosomatic ratio, germ cell count and verification of variation of mature oocytes in females. Throughout the year the male gonads presented themselves as capable of reproducing, characterized by the presence of undifferentiated and differentiated spermatogonia, spermatocytes organized into cysts, spermatids in cysts whose wall was thicker and the spermatozoa was free in the lumen and the duct. This can indicate a continuous reproductive cycle with split spermiation. The females had gonads in the development stage from May to September with undifferentiated and differentiated oogonias and early oocytes always facing the lumen, abundant pre-vitellogenic and vitellogenic oocytes and some atresias. In the phase capable of spawning, observed from October to March, the mature oocytes are abundant, there are many post-ovulatory complexes and some atresia in advanced stage. The regression, observed in some individuals from February to April, is characterized by ovaries with many atresias and post-ovulatory complexes. The same results were found in the quantitative assessments. Therefore, it may be characterized as discontinuous cycle with split spawning. Thus, the reproductive cycle of this species can be characterized as continuous for males and discontinuous for females, which have a most intense phase of reproduction from October to March. However, both have fractional release of gametes.

The reproductive cycle in anurans may be either continuous or discontinuous. These differences may be connected to seasonal climate changes and/or to anthropic activity. Forty adult male individuals of the Dendropsophus minutus species were collected during one year, in the municipality of Chapada dos Guimarães (Mato Grosso, Brazil). The testicles were studied under light and transmission electron microscopy. No variations were observed when the diameter of the seminiferous tubules and the thickness of the interstitial tissue were studied. However, changes in spermatogenesis were conspicuous and indicated that the reproductive cycle of D. minutus in Chapada dos Guimarães is discontinuous and seems related to variations in air temperature and rainfall.

Reproductive strategy is the set of adaptations that promote the most efficient way that the species will survive under the particular conditions of a determined environment. Understanding these adaptations is important and can help pinpoint populations indicator of environmental changes. Spermatogenesis is a measurable biological process of these adaptations in spatial and temporal scales. We analyzed the morphology of the testes and oviducts of the lizard species that comprise the genus Tropidurus, taking into account the geographical distribution and sympatric relations. For the analysis and the testes were removed from the middle part of the oviducts from Tropidurus etheridge, T. oreadicus, T. itambere, T. spinulosus and T. Guarani species, collected in different places in the Mato Grosso state, Brazil. The reproductive period is synchronous for males and females and occurs in September, October and November. Reproductive males were characterized. In the testes are seminiferous tubules with germ cells at different stages of spermatogenesis, with a high epithelium, at present light, free spermatozoa in the lumen and reduction of interstitial tissue. For females, the reproduction peak occurs when the oviduct epithelium is high with secretions and basal nucleus. These months are characterized in the sampled areas over a period of heavy rain and high temperatures. The decline of reproductive period was observed in both sexes, between April and August. Low reproduction in males is characterized by ample light, absence of sperm, only germ cells in the early stages of spermatogenesis are observed (a few spermatogonia and spermatocytes) and interstitial tissue wide. In females, the period of reproductive decline is marked by the absence of unicellular glands in the oviduct epithelium, with higher affinity with the dye. This period corresponds to low rainfall periods and lower temperatures. We propose an analysis of zoological samples; this is a proposal to facilitate the work of many researchers through access to the species, especially rare species.

Estrategia reproductiva es el conjunto de adaptaciones que promueven la manera más eficiente para una población a sobrevivir en las condiciones específicas de un entorno particular. Comprender esta adaptación es importante y puede identificarse en algunas poblaciones como indicador de cambios ambientales. La espermatogénesis puede ser un proceso biológico medible de estas adaptaciones en escalas espaciales y temporales. Se analizó la morfología de los testículos y oviductos de las especies de lagartijas que componen el género Tropidurus, teniendo en cuenta la amplia distribución geográfica y las relaciones simpátricas. Para el análisis hemos eliminado los testículos de los machos y la parte media de los oviductos de hembras de las especiesTropidurus Etheridge, T. oreadicus, T. itambere, T. spinulosus y T. Guarani recolectadas en diferentes lugares en el estado de Mato Grosso, Brasil. El período reproductivo es sincrónico para machos y hembras, y se produce durante septiembre, octubre y noviembre. Se caracterizaron como machos reproductores por testículos con túbulos seminíferos con células germinales en distintas etapas de la espermatogénesis, un epitelio muy alto, un lumen reducido, numerosos espermatozoides libres en el lumen y tejido intersticial redicudo. En hembras el pico reproductivo se produce cuando los canales de conducción de gametos poseen un epitelio alto, secretor y con núcleos basales. Estos meses son caracterizados en las zonas muestreadas por fuertes lluvias y altas temperaturas. La disminución del período reproductivo se observó en ambos sexos, entre abril y agosto. La baja reproducción en machos se caracteriza por un lumen ancho, ausencia de espermatozoides, presencia de células germinales sólo en las primeras etapas de la espermatogénesis (espermatogonias y pocos espermatocitos) y tejido intersticial amplio. En las mujeres, el período de baja reproducción está marcado por la ausencia de glándulas unicelulares en el epitelio del oviducto, con mayor afinidad a la tinción. Este período corresponde al de baja precipitaciones y temperaturas más bajas. Proponemos un análisis de muestras de las colecciones zoológicas ya que esta es una propuesta para facilitar el trabajo de muchos investigadores a través del acceso a las especies, especialmente especies raras.

A morfologia bucal interna das larvas de Eupemphix nattereri, Physalaemus albonotatus, P. centralis, P. cuvieri, Leptodactylus furnarius, L. fuscus, L. petersii e L. podicipinus são descritas e comparadas utilizando microscopia eletrônica de varredura. A larva de E. nattereri apresenta muitas diferenças quando comparada à larvas de anuros do gênero Physalaemus. As larvas de P. albonotatus, P. centralis e P. cuvieri apresentam semelhanças em sua morfologia bucal interna, tais como o número de papilas infralabiais e papilas laterais à crista mediana. P. centralis difere na quantidade de papilas pós-nasais e papilas da arena do teto bucal. Entre as larvas de Leptodactylus é possível perceber um padrão na distribuição e quantidade das estruturas bucais internas (papilas infralabiais e linguais, papilas das arenas do assoalho e teto bucal, crista mediana, papilas laterais da crista e papilas pós-nasais) nos grupos de espécies. Os caracteres da morfologia bucal larvária podem ser úteis quando utilizados conjuntamente com outros dados auxiliando na compreensão das relações sistemáticas da ordem Anura.

The internal buccal morphology of the tadpoles of Eupemphix nattereri, Physalaemus albonotatus, P. centralis, P. cuvieri, Leptodactylus furnarius, L. fuscus, L. petersii and L. podicipinus are described and compared using scanning electron microscopy. The tadpole of E. nattereri has major differences when compared to other tadpoles of the Physalaemus genus. The tadpoles of P. albonotatus, P. centralis and P. cuvieri present similarities in internal buccal morphology, such as the number of the infralabial and lateral ridge papillae, but P. centralis differ in the number of the post-narial and buccal roof arena papillae. Among the tadpoles of the Leptodactylus species is possible to observe patterns, in distribution and quantity of the internal buccal structures (infralabial and lingual papillae, buccal floor and roof arena papillae, median ridge, lateral ridge papillae and postnarial papillae) in the species groups. The characteristics of the internal buccal morphology may be useful when used together with other data helping in comprehension of the systematic of the order Anura.

The spermatogenesis of Pseudis limellum, from the Southern Pantanal, Brazil, was studied from July 1995 to May 1996, through histological sections of the testis. The cells could be differentiated as: primary spermatogonia, large cells, generally with bilobed nucleus; secondary spermatogonia, smaller cells, with darker cytoplasm, chromatin of radial form; primary and secondary spermatocytes, differentiated according to the different stages of the nucleus during the successive cells divisions. Furthermore, we observed cells in process of morphologic differentiation: rounded spermatids much smaller, with nucleus containing chromatin in compacting process and cytoplasm reduction; elongated spermatids, generally parallel organized in well defined bundles, with the anterior region directed toward the periphery of the seminiferous tubule and the tail directed toward the lumen. Spermatozoa are free in the lumen of the seminiferous tubule. All the cells are organized as cysts, which are supported by a large amount of Sertoli cells. The spermatogenesis in P. limellum is very similar to that of other anurans, but peculiarities were observed regarding the organization of the germ cells, the great amount of free Sertoli cells in the lumen of testis collected in May, and the long cytoplasmatic extensions of the cells bearing pigments and involving the seminiferous tubule. The diameter of the seminiferous tubule (SD) exhibited an annual mean of 251.79 ± 37.57 μm. Spermatozoa number by seminiferous tubule (SN) exhibited an annual mean of 306.66 ± 39.83, also with higher and lower values at each month. Variations in SD and SN were not significantly correlated with climatic variables. In this species, reproduction occurs throughout the year in ponds and flooded areas, despite the seasonal climate of the Pantanal. Although males varied in their annual reproductive activity, they were considered potentially reproductive in all months throughout the year

A microanatomia do disco oral e da cavidade bucal da larva de Leptodactylus labyrinthicus é descrita e comparada com outras espécies do gênero pertencentes ao grupo de L. pentadactylus. Trinta e cinco girinos entre os estágios 25 e 46 foram dissecados e analisados em microscopia eletrônica de varredura. A descrição da morfologia oral foi feita utilizando larvas entre os estágios 36 e 39. A morfologia oral da larva de L. labyrinthicus é similar às descritas para outros girinos com adaptação a macrofagia, com forte queratinização das coberturas das mandíbulas, redução das estruturas bucais internas e presença de uma glote descoberta, propícias às dietas carnívoras. As larvas do grupo de L. pentadactylus compartilham essa tendência à redução das estruturas de seleção e captura de partículas, apresentando redução no número de papilas da arena do assoalho e do teto bucal, redução ou ausência das papilas anteriores às bolsas bucais, apenas duas papilas pós-nasais, pequenas papilas laterais à crista mediana e zonas glandulares restritas a estreitas faixas no bordo velar. Nos girinos do gênero Leptodactylus a morfologia larvária reflete os grupos atuais propostos para o gênero.

The microanatomy of the oral disc and the buccal cavity of the tadpole of Leptodactylus labyrinthicus is described and compared with other species included in the L. pentadactylus species group. Thirty-five tadpoles between stages 25 and 46 had been dissected and analyzed in scanning electron microscopy. The oral and internal buccal morphology was analyzed in tadpoles between stages 36 and 39. The buccal morphology of the tadpole of L. labyrinthicus is similar to other tadpoles with adaptation to macrophagy, such as the strong queratinization of the jaw, reduction of the internal buccal structures and presence of one glote uncovered, propitious to carnivorous diets. The tadpole of L. pentadactylus species group share this trend to the reduction of the structures of selection and capture of particle, including reduction in the number of the buccal roof and floor arena papillae, reduction or absence of anterior papillae on the buccal pocket, only two postnarial papillae, small lateral ridge papillae and glandular zones restricted in narrow bands on the edge of velum. In the tadpoles of genera Leptodactylus the larval morphology reflects the current groups considered for this genera.

Spermatogenesis, with emphasis on spermiogenesis, is described for the lizard, Tropidurus itambere, using light microscopy, phase contrast and epifluorescence, as well as scanning and transmission electron microscopy. Cellular differentiation involves events of chromatin condensation, nuclear elongation and the formation of structural complexes, such as the acrosomal and axonemal ones. Other new characteristics, exclusive for this species, include various aspects of the subacrosomal granule, the insertion of the pro-acrosomal vesicle and the development of these structures to participate in the acrosomal complex. Radial projections occur just above the nuclear shoulders, which have been recognized already from the beginning of cellular elongation. The development of the midpiece, the dense bodies, formation of the flagellum and elimination of residual cytoplasm result in the final characterization of the mature spermatozoon. Comparisons between Tropiduridae and other lizard families are made.