RESUMO

Sperm morphology is considered the best indicator of male fertility. In Neotropical bats, important aspects of sperm morphology have been scantly studied. The aim of the present study was to characterize and compare the sperm morphology and morphometry of Artibeus planirostris and Sturnira erythromos. A total of 11 specimens were analyzed from the Colección de Mamíferos Lillo: five A. planirostris and six S. erythromos. The fixed epididymis were extracted and macerated in Farmer's solution, followed by the routine cytological procedure with different stains. To carry out the description and morphometric analysis, microphotographs were taken under an optical, epifluorescence and scanning electron microscope. A total of 50 sperm from each individual were measured for morphometric analysis. The percentage of normal/abnormal spermatozoa was estimated and the sperm abnormalities were classified. Both species showed morphologically simple spermatozoa with a spatulate head, a short neck, a helical midpiece and a tail that tapers at the final end, similar to other species of Phyllostomidae. The differences observed were: apex of the head was conical in A. planirostris and was oval in S. erythromos; longer head and midpiece in S. erythomos and longer sperm in A. planirostris. Both species showed a high percentage of sperm with normal appearance: 65% for A. planirostris and 72% for S. erythromos. The main sperm abnormalities were: scattered tails and heads, coiled tails, folded midpieces and presence of cytoplasmic droplets. The present work will improve the understanding of their reproductive biology. RESEARCH HIGHLIGHTS: Morphological descriptions and morphometric analyses of the sperm of Artibeus planirostris and Sturnira erythromos were carried out with optical, epifluorescence and scanning electron microscopy.

RESUMO

Sperm morphology is considered a species-specific character and has been used as a tool in the classification of numerous mammalian taxa. Neotropical bats have been poorly studied, and important aspects on sperm morphology have not been elucidated. The aim of the present study was to describe and compare the sperm morphology and morphometry of Molossus molossus and Molossops temminckii. A total of 14 adults specimens were analyzed from the Colección Mamíferos Lillo, Universidad Nacional de Tucumán: five M. molossus and nine M. temminckii. The epididymis were extracted and macerated in Farmer's solution, followed by a coloration with different stains. To carry out the description and morphometric analysis, microphotographs were taken under an optical, epifluorescence, and scanning electron microscope (SEM). A total of 50 sperm from each individual were measured for morphometric analysis. The length and width of the head, midpiece and tail were taken as variables. Sperm from M. molossus and M. temminckii were practically identical, both morphologically and morphometrically. In both species, a distal bulge was observed at the end of the intermediate piece in a percentage greater than 85%. The main characteristics shared between the species were: presence of acrosomal blebs in the upper half of the head of the spermatozoa; cephalic equatorial segment with filiform ornamentations; intermembrane space of head apex wedge-shaped; helical middle piece and annulus at the end of middle piece. In the present study, SEM allowed us to visualize structures, such as acrosomal vesicles, that were not detected with other types of microscopy. RESEARCH HIGHLIGHTS: The similarities in the sperm morphology between M. molossus and M. temminckii were observed with three types of microscopy: optical, epifluorescence and scanning electron, and supported by morphometric and statistical analyses.

Assuntos

RESUMO

The reproductive accessory glands (RAG) are essential components in reproduction because their secretion products ensure survival, viability, and sperm motility. The objective of this study was to characterize and compare the morphological and histological structure of the RAG in three species of bats of the genus Sturnira (S. erythromos, S. lilium, and S. oporaphilum). The RAG complex comprise a compact gland (prostate), which surrounds the urethra, and a pair of Glands of Cowper at the base of penis. Anatomical and histologically, the prostate are differentiated in two regions, ventral and dorsal. The dorsal region has tubuloalveolar glands with secretions fine granular or accumulations of a gel-like substance with bubbles and the ventral region, has alveolar glands with secretory cells form a single-layer of small cells. The seminal vesicles are absent. The prostatic morphology of the three species is similar to that of other studied Stenodermatinae and Desmodontinae, but differs from other subfamilies of Phyllostomidae (Carollinae, Glossophaginae, and Phyllostominae) as that of Molossidae and Vespertilionidae. The RAG complex has no annual variation in relation to functionality or size, but it is variable depending on age (subadults and adults). This agrees with the annual reproductive pattern described for these species in these latitudes, where adult males are reproductively active throughout the year.

Assuntos

RESUMO

Seven new species of Myotis have been recently described from South America, elevating to 20 the total number of species of the genus recognized for the region. Myotis izecksohni and Myotis lavali were recently described from the States of Rio de Janeiro, Paraná and Pernambuco, Brazil. These are clearly different from all other known species of the genus in their external and cranial characters, which are exactly comparable with our specimens collected in Argentina. This allows to greatly expand the known geographic distributions for these two species. The addition to Argentina of Myotis lavali with specimens collected in the Yungas ecoregion of Salta Province, and Myotis izecksohni with specimens collected in the Fields and Weedlands ecoregion of Misiones Province, increases the known ecoregions to date for the distribution of the two species.

Siete nuevas especies de Myotis han sido recientemente descriptas en Sud América elevando a 20 el número de especies del género conocidas para la región. Myotis izecksohni y Myotis lavali han sido descriptas recientemente mediante ejemplares procedentes de los Estados de Río de Janeiro, Paraná y Pernambuco, Brasil. Estas especies son claramente diferentes de todas las otras conocidas del género, tanto en sus características externas como craneales, dichos caracteres coinciden exactamente con los de ejemplares encontrados en Argentina. Estos hallazgos permiten extender significativamente la extensión distribucional de las dos especies, e incluir a Myotis lavali en la eco-región de las Yungas en la provincia de Salta, y a Myotis izecksohni en la eco-región de los Campos y Malezales de la provincia de Misiones. Dichas eco-regiones no eran conocidas para la distribución de las nuevas especies.

Assuntos

RESUMO

Seven new species of Myotis have been recently described from South America, elevating to 20 the total number of species of the genus recognized for the region. Myotis izecksohni and Myotis lavali were recently described from the States of Rio de Janeiro, Paraná and Pernambuco, Brazil. These are clearly different from all other known species of the genus in their external and cranial characters, which are exactly comparable with our specimens collected in Argentina. This allows to greatly expand the known geographic distributions for these two species. The addition to Argentina of Myotis lavali with specimens collected in the Yungas ecoregion of Salta Province, and Myotis izecksohni with specimens collected in the Fields and Weedlands ecoregion of Misiones Province, increases the known ecoregions to date for the distribution of the two species.(AU)

Siete nuevas especies de Myotis han sido recientemente descriptas en Sud América elevando a 20 el número de especies del género conocidas para la región. Myotis izecksohni y Myotis lavali han sido descriptas recientemente mediante ejemplares procedentes de los Estados de Río de Janeiro, Paraná y Pernambuco, Brasil. Estas especies son claramente diferentes de todas las otras conocidas del género, tanto en sus características externas como craneales, dichos caracteres coinciden exactamente con los de ejemplares encontrados en Argentina. Estos hallazgos permiten extender significativamente la extensión distribucional de las dos especies, e incluir a Myotis lavali en la eco-región de las Yungas en la provincia de Salta, y a Myotis izecksohni en la eco-región de los Campos y Malezales de la provincia de Misiones. Dichas eco-regiones no eran conocidas para la distribución de las nuevas especies.(AU)

Assuntos