Mitochondrial genome of Pteronotus personatus (Chiroptera: Mormoopidae): comparison with selected bats and phylogenetic considerations.

We described the complete mitochondrial genome (mitogenome) of the Wagner's mustached bat, Pteronotus personatus, a species belonging to the family Mormoopidae, and compared it with other published mitogenomes of bats (Chiroptera). The mitogenome of P. personatus was 16,570 bp long and contained a typically conserved structure including 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and one control region (D-loop). Most of the genes were encoded on the H-strand, except for eight tRNA and the ND6 genes. The order of protein-coding and rRNA genes was highly conserved in all mitogenomes. All protein-coding genes started with an ATG codon, except for ND2, ND3, and ND5, which initiated with ATA, and terminated with the typical stop codon TAA/TAG or the codon AGA. Phylogenetic trees constructed using Maximum Parsimony, Maximum Likelihood, and Bayesian inference methods showed an identical topology and indicated the monophyly of different families of bats (Mormoopidae, Phyllostomidae, Vespertilionidae, Rhinolophidae, and Pteropopidae) and the existence of two major clades corresponding to the suborders Yangochiroptera and Yinpterochiroptera. The mitogenome sequence provided here will be useful for further phylogenetic analyses and population genetic studies in mormoopid bats.

Serotonin in testes of bat Myotis velifer during annual reproductive cycle: expression, localization, and content variations.

The mechanism of reproduction in mammals is very complex and in some cases is quite particular. For example in some bat species, the male presents a reproductive mechanism characterized by an annual testicular cycle that goes from recrudescence to regression (spermatogenesis to inactivity period, respectively). After recrudescence, the spermatozoa arrive at epididymis and wait to be expelled at the time of ejaculation during the mating period, which occurs some months later. Because serotonin (5-HT) has gained reproductive importance in the last years, the aim of the present study was to analyze the expression of this indolamine and both tryptophan hydroxylase and monoamine oxidase isoform A-enzymes involved in its metabolism-in Myotis velifer testes, a seasonal reproductive bat species that shows temporal asynchrony in its sexual cycle, across the principal periods of their reproductive cycle. By using both Falck-Hillarp histochemistry and immunofluorescence techniques, we found serotonin in vesicles of Leydig cells and probably Sertoli cells too; interestingly, both intracellular localization and concentration was variable across the different stages of the reproductive cycle, being lower during spermatogenesis phase and increasing during the mating phase. These results suggest that 5-HT is present in bat testes and it could play an important role in testicular function during their reproductive cycle.

[Population dynamics, roost selection and reproductive patterns of some cave bats from western of Mexico]. / Dinámica poblacional, selección de sitios de percha y patrones reproductivos de algunos murciélagos cavernícolas en el oeste de México.

Population dynamics, roost selection and reproductive patterns of some cave bats from Western of Mexico. Almost half of bat species that occur in Mexico use caves as permanent or temporal roosts. However, the ecological studies about cave bat communities are scarce. In this work we studied the population dynamics, roost selection and reproductive patterns of some bats present in El Salitre Cave, Colima, Mexico. We carried out monthly samplings between August 2003-March 2005 using a harp trap for bats capture, we took their biological data and marked some of them with plastic rings. We also explored the cave to locate bat colonies and register microclimatic conditions in each cave section. We captured a total of 16 409 bats of which 31% were Mormoops megalophylla, 24.5% Pteronotus personatus, 23% P. davyi, 8.2% P. parnellii, 5.8% Natalus mexicanus and 5.3% Glossophaga soricina. Macrotus waterhousii, G. morenoi, Desmodus rotundus, Balantiopteryx plicata, and Glyphonycteris sylvestris represented only 2.2% of the captures. Some bat species used the cave as a permanent day roost while others as a seasonal one, and their population size varied markedly along the year and between rainy and dry seasons. Most bat population peaks were linked with their reproductive periods. The Pteronotus species and N. mexicanus exhibited sexual segregation during the breeding season. The mormoopids and N. mexicanus occupied deeper parts of the cave with temperatures >25.8 degrees C and relative humidity >99%. The phyllostomids occupied intermediate sections where the ambient was less hot and humid, with temperatures of 23.2-28.3 degrees C and humidity of 74-89.9%. Some individuals of B. plicata and G. sylvestris were seen occasionally occupying one chamber near the entrance two, where temperature and humidity were of 23.2 degrees C and 84.2%, respectively. The mormoopids and N. mexicanus showed a pattern of seasonal monoestry, synchronized with rainy season. Glossophaga soricina had a pattern of bimodal seasonal poliestry, with one reproductive peak to early of dry season and another to last of this season. Macrotus waterhousii did not exhibit a seasonal pattern, with parturitions occurring throughout the year. Our results indicate a seasonal replacement between several species as well as seasonal movements to other caves. The data indicate that the carrying capacity of the cave is mainly determined by the availability of roosting sites. The selection of roosting sites is linked to the close relationship between microclimatic conditions and the species physiological characteristics. The reproduction of mormoopids and N. mexicanus was mostly influenced by rainfall which determinates food availability.

Dinámica poblacional, selección de sitios de percha y patrones reproductivos de algunos murciélagos cavernícolas en el oeste de México / Population dynamics, roost selection and reproductive patterns of some cave bats from Western of Mexico

Almost half of bat species that occur in Mexico use caves as permanent or temporal roosts. However, the ecological studies about cave bat communities are scarce. In this work we studied the population dynamics, roost selection and reproductive patterns of some bats present in El Salitre Cave, Colima, Mexico. We carried out monthly samplings between August 2003-March 2005 using a harp trap for bats capture, we took their bio- logical data and marked some of them with plastic rings. We also explored the cave to locate bat colonies and register microclimatic conditions in each cave section. We captured a total of 16 409 bats of which 31% were Mormoops megalophylla, 24.5% Pteronotus personatus, 23% P. davyi, 8.2% P. parnellii, 5.8% Natalus mexicanus and 5.3% Glossophaga soricina. Macrotus waterhousii, G. morenoi, Desmodus rotundus, Balantiopteryx plicata, and Glyphonycteris sylvestris represented only 2.2% of the captures. Some bat species used the cave as a permanent day roost while others as a seasonal one, and their population size varied markedly along the year and between rainy and dry seasons. Most bat population peaks were linked with their reproductive periods. The Pteronotus species and N. mexicanus exhibited sexual segregation during the breeding season. The mormoopids and N. mexicanus occupied deeper parts of the cave with temperatures >25.8°C and relative humidity >99%. The phyllostomids occupied intermediate sections where the ambient was less hot and humid, with temperatures of 23.2-28.3°C and humidity of 74-89.9%. Some individuals of B. plicata and G. sylvestris were seen occasionally occupying one chamber near the entrance two, where temperature and humidity were of 23.2°C and 84.2%, respectively. The mormoopids and N. mexicanus showed a pattern of seasonal monoestry, synchronized with rainy season. Glossophaga soricina had a pattern of bimodal seasonal poliestry, with one reproductive peak to early of dry season and another to last of this season. Macrotus waterhousii did not exhibit a seasonal pattern, with parturitions occurring throughout the year. Our results indicate a seasonal replacement between several species as well as seasonal movements to other caves. The data indicate that the carrying capacity of the cave is mainly determined by the availability of roosting sites. The selection of roosting sites is linked to the close relationship between microclimatic conditions and the species physiological characteristics. The reproduction of mormoopids and N. mexicanus was mostly influenced by rainfall which determinates food availability.

Estudiamos la ecología poblacional y reproducción de algunas especies de murciélagos presentes en una cueva del oeste de México. Entre agosto 2003-marzo 2005 capturamos 16 409 individuos de los cuales 86.7% pertenecieron a miembros de la familia Mormoopidae, 7.4% a Phyllostomidae, 5.8% a N. mexicanus y 0.1% a B. plicata. Los números poblacionales de las especies varían notablemente a lo largo del año y entre temporadas. Segregación sexual durante la época reproductiva sucede en Pteronotus y N. mexicanus. Los mormópidos y N. mexicanus ocuparon las partes más profundas de la cueva donde imperan temperaturas >25.8°C y humedad >99%. Los filostómidos ocuparon las secciones intermedias con temperaturas de 23.2-28.3°C y humedad de 74-89.9%; B. plicata y G. sylvestris ocuparon una cámara con temperatura de 23.2°C y humedad del 84.2%. Los mormópidos y N. mexicanus exhibieron un patrón monoéstrico estacional, G. soricina presentó un patrón poliéstrico bimodal estacional y M. waterhousii exhibió un patrón reproductivo continuo. Nuestros resultados indican un reemplazamiento estacional entre varias especies, así como movimientos estacionales hacia otras cuevas. La selección de los sitios de percha esta ligada a las condiciones microclimáticas del refugio y la fisiología de las especies. La reproducción de las especies insectívoras esta influida por la precipitación que determina la disponibilidad del alimento.

Spermatozoa epididymal maturation in the Mexican big-eared bat (Corynorhinus mexicanus).

Prolonged epididymal sperm storage in vespertilionid and rhinolophid bats, provides an interesting experimental model for the study of spermatozoa epididymal maturation. We examined the presence of the cytoplasmic droplet, and the sequential induction of capacitation and the acrosome reaction in spermatozoa obtained from different epididymal regions (caput, corpus, cauda) throughout the annual reproductive cycle of Corynorhinus mexicanus (C. mexicanus). This is a vespertilionid bat that stores spermatozoa in the epididymis for several months after testes regression. The number of sperm recovered from the different epididymal regions indicate that epididymal transit in C. mexicanus is rapid. The persistence of a high percentage of sperm cells with cytoplasmic droplet in cauda epididymis was observed in addition to a low index of capacitation and acrosome reaction in sperm cells obtained from the corpus epididymis. There was a significant increase in the percentage of capacitated and acrosome reacted spermatozoa during the storage of sperm cells in the cauda epididymis and the percentage of capacitated spermatozoa was consistently, and significantly, higher (p < 0.05) in cauda compared to the corpus epididymis at all studied dates. The process of epididymal maturation in C. mexicanus is completed in the caudal region of this organ encompassing a significant period. Our results also indicate that in C. mexicanus, and in other vespertilionid and rhinolophid bats that show the same temporal asynchrony in the function of male reproductive organs, the final phases of epididymal maturation and storage are, apparently, independent of testicular function.