Species Of Vespertilionid Bats Research Articles

Risk of infection of white-nose syndrome in North American vespertilionid bats in Mexico

Emerging diseases in wildlife pose challenges for conservation due to their usually rapid spread and high cause of mortality. The transmission of these diseases is a complex ecological process that involves interactions between groups of individuals, particularly in gregarious species. White-nose syndrome, caused by the fungus Pseudogymnoascus destructans, is increasingly infecting species of vespertilionid North American bats causing, in some cases, high population mortality. In this study, we modeled ecological niches projected as potential distributions for three strains of P. destructans (Asian, European and North American) and a group of species of verpertilionid bats in North America. Our model showed that the ecological niches of North American and Asian fungi strains are projected to expand into new geographic areas, with statistical significance between the two strains. In addition, our model identified the presence of all three strains of fungi in areas where the fungus has previously been documented as well as new suitable climatic areas for the establishment of P. destructans in North America: large regions of the central USA and highlands of Mexico in the Peninsula of Baja California, the Sierra Madre Occidental and Oriental, and Transvolcanic Mexican Belt. Our models identified 10 species of vespertilionid bats distributed similarly to P. destructans. Bats had a high risk of infection with WSN and a strong likelihood of dispersing the fungus.

Molecular characterization of Polychromophilus parasites of Scotophilus kuhlii bats in Thailand.

Parasites of the haemosporidian genus Polychromophilus have exclusively been described in bats. These parasites belong to the diverse group of malaria parasites, and Polychromophilus presents the only haemosporidian taxon that infects mammalian hosts in tropical as well as in temperate climate zones. This study provides the first information of Polychromophilus parasites in the lesser Asiatic yellow bat (Scotophilus kuhlii) in Thailand, a common vespertilionid bat species distributed in South and Southeast Asia. The gametocyte blood stages of the parasites could not be assigned to a described morphospecies and molecular analysis revealed that these parasites might represent a distinct Polychromophilus species. In contrast to Plasmodium species, Polychromophilus parasites do not multiply in red blood cells and, thus, do not cause the clinical symptoms of malaria. Parasitological and molecular investigation of haemosporidian parasites of wildlife, such as the neglected genus Polychromophilus, will contribute to a better understanding of the evolution of malaria parasites.

The effect of group size, reproductive condition and time period on sexual segregation patterns in three vespertilionid bat species

AbstractSexual segregation is widespread across the animal kingdom, yet there is limited consensus on the factors that shape this behavioural phenomenon. Many of the existing theories are based on study species with high levels of sexual size dimorphism. Insights from studies on species with minimal sexual size dimorphism, such as vespertilionid bats, provide an opportunity to study the factors associated with segregation irrespective of body size effects. Using long‐term data pooled from multiple bat box monitoring schemes across the U.K., we investigated segregation patterns in maternity roosts of three vespertilionid bat species, Bechstein’s bat, Myotis bechsteinii, Natterer’s bat, M. nattereri and brown long‐eared bat, Plecotus auritus. We used the Sexual Segregation and Aggregation Statistic (SSAS) to evaluate temporal trends of sexual segregation of roosts over the reproductive period (divided into pre‐parturition, lactation and post‐lactation periods). Additionally, we used generalized linear mixed models and beta regression models to investigate the effect of group size on segregation patterns. Our results showed that the size of the maternity group was an important covariate of inter‐ and intra‐sexual segregation, with males and non‐breeding females typically segregated from large maternity groups across all three periods. Additionally, we demonstrate that reproductive condition and period influence segregation patterns, with breeding females segregated from non‐breeding females and males during the lactation period. Although sexual segregation may be caused by multiple mechanisms, our results show that group size, female reproductive condition and time period are key factors associated with segregation within bat roosts. These findings make a valuable contribution to the understanding of inter‐ and intra‐sexual segregation in vespertilionid bats and complement existing research on segregation in other mammalian taxa, providing further evidence that sexual size dimorphism is not a prerequisite for sexual segregation.

Histomorphology of the glans penis in Vespertilionidae and Phyllostomidae species (Chiroptera, Mammalia).

The penises of bats are taxonomically distinctive in size and shape. In addition, they are variable in microscopic anatomy, indicating that histomorphological studies of copulatory organs of bats may help understanding their successful reproductive strategies. We studied adult males of 13 species of vespertilionid and phyllostomid bats. Both families exhibited the basic structure of the vascular penis of mammals: the hydrostatic elements of the corpora cavernosa and the corpus spongiosum surrounding the urethra, as well as accessory cavernous tissue. Variation in the position and amount of the tissues were observed in these families. Vespertilionid bats have a small glans penis with abundant accessory cavernous tissue on the prepuce and a highly variable baculum. The baculum varied in size and morphology, even among congeneric species, such as the three Lasiurus species and the two Myotis species. Phyllostomid species possess no bacula, but vascular structures are present to produce penile stiffening, particularly on the glans. Variation in the microscopic anatomy of the phyllostomid prepuce was observed, for example, Artibeus species had accessory cavernous tissue surrounded by a tunica albuginea, but Carollia perspicillata had two bundles of striated musculature and some adipose tissue; abundant pigments were present in the prepuce of most species.

A New Genus and Species of Vesper Bat from West Africa, with Notes on Hypsugo, Neoromicia, and Pipistrellus (Chiroptera: Vespertilionidae)

We describe a new species of vespertilionid bat from Guinea and Liberia, West Africa. In this context we evaluate previously described taxa from West Africa assigned to Pipistrellus, Neoromicia, and Hypsugo. Based on genetics, morphology and ecology we conclude that the taxon Pipistrellus eisentrauti bellieri should be elevated to species level, and that the taxa bellieri, crassulus, eisentrauti plus the new species form a monophyletic clade for which a new genus name is proposed. The new genus occurs in forested regions south of the Sahara from Senegal to Ethiopia and Somalia, from where further taxa remain to be described.

Wing morphology predicts geographic range size in vespertilionid bats

Why some species are widespread across continents while others are confined geographically remains an open question in ecology and biogeography. Previous research has attempted to explain interspecific variation in geographic range size based on differences in dispersal ability. However, the relationship between dispersal ability and geographic range size remains uncertain, particularly in mammals. The goal of this study is to test whether geographic range size can be predicted by dispersal capacity among vespertilionid bats within a phylogenetic comparative framework. We integrated a large dataset on range area, longitudinal extent, wing morphology (a proxy for dispersal ability), migratory habit, and biogeographic realm across 126 vespertilionid bat species. We used phylogenetic regressions to disentangle the associations between these predictor factors and species range size while controlling for the effects of migration and biogeographic realm. Our analyses revealed that bat species with higher wing loading exhibit larger distribution ranges than those with lower wing loading, and that the size of geographic ranges was associated with wing aspect ratio in bats. These results highlight the relationship between wing morphology and range size in flying mammals, and suggest a role of dispersal capacity in shaping species’ geographic distributions.

Spatiotemporal Characteristics of Quadrupedal Locomotion in Vespertilionid Bats

Abstract—Chiroptera is the order of the only mammals to have acquired flapping flight. Their musculoskeletal system is significantly reorganized. In addition, their four-legged locomotion is fundamentally different from that in typical mammals. The most up-to-date information on the terrestrial locomotion concerns the species expressing this type of movement as an integrated component of foraging behavior. Quadrupedal locomotion of other bats remains practically unstudied. This paper presents the results of experimental analysis of four-legged terrestrial locomotion in five species of vespertilionid bats. The study is based on a combination of two methods: two-angle high-speed video recording and animals’ trackways and traces analysis. The temporal, metric, and speed parameters for locomotion in different species are estimated. The dependence of the characteristics between each other is proven. This is the first time that such parameters have been studied in Chiroptera. A diagonal symmetry for the pattern of the sequential movement of limbs has been detected, while it involves a wide range of deviations atypical for quadrupedal vertebrates.

A new genus and species of vespertilionid bat from the Indomalayan Region.

Bats belonging to the subfamily Vespertilioninae are diverse and cosmopolitan, but their systematic arrangement remains a challenge. Previous molecular surveys suggested new and unexpected relationships of some members compared to more traditional, morphology-based classifications, and revealed the existence of taxonomically undefined lineages. We describe here a new genus and species corresponding to an enigmatic lineage that was previously identified within the genus Eptesicus in the Indomalayan Region. Phylogenetic reconstructions based on mitochondrial and nuclear genes relate the new taxon to Tylonycteris and Philetor, and show that specimens associated with this new genus represent 2 genetically distinct species. Although little is known about their ecology, locations of capture and wing morphology suggest that members of this new genus are tree-dwelling, open-space aerial insect predators. The new species has only been documented from Yok Don National Park in Vietnam, so its conservation status is uncertain until more surveying methods target the bat fauna of the dipterocarp forest in Southeast Asia.

First Record of the Collared Sprite, Thainycteris aureocollaris (Chiroptera, Vespertilionidae) from China

Abstract. Thainycteris aureocollaris is a rare vespertilionid bat species reported from remote forest habitats of Lao PDR, Vietnam, and Thailand. In 15 September 2015, one Vespertilionid bat with a well-defined ochraceous collar running from the base of ears across the throat was collected at Shuijia Village, Guizhou Province, China. Based on its morphological characteristics and phylogenetic inference using partial cytochrome c oxidase subunit I gene, it was identified as T. aureocollaris, representing the first record of the species in China. This northernmost occurrence largely extends the species' potential distribution area, and through Maxent modeling, its potentially suitable habitats are mapped herewith.

A Second Endemic Land Mammal for the Hawaiian Islands: A New Genus and Species of Fossil Bat (Chiroptera: Vespertilionidae)

ABSTRACT Located over 3800 km from the nearest continent, the Hawaiian Islands have previously been thought to support only one endemic land mammal, the extant Hawaiian hoary bat (Lasiurus cinereus semotus), a taxon that apparently initially dispersed from mainland North America between 10,000 and 7000 years ago. Some uncertainty exists regarding the status of this taxon (i.e., whether or not populations representing more recent invasions of L. cinereus from North America are exchanging genes with the older lineage, and whether or not semotus represents a distinct species), but all researchers agree that hoary bats are the only endemic land mammals extant in the islands today. However, fossil evidence indicates that the Hawaiian Islands once supported another quite different endemic bat species that is now extinct. Skeletal remains of a new genus and species of vespertilionid bat are herein described from various Late Pleistocene and Holocene/Recent deposits on the five largest Hawaiian Islands. The new t...

The complete mitochondrial genome of Kuhl’s pipistrelle, Pipistrellus kuhlii (Chiroptera: Vespertilionidae)

The Kuhl’s pipistrelle (Pipistrellus kuhlii) is a small, vespertilionid bat species, with a large range extending from the Iberian Peninsula into the Near East and the Arabian Peninsula. In this study, we determine for the first time the complete mitogenome of this species. The P. kuhlii mitogenome is 16,991 base pairs long with 37 genes and 1 control region, showing conserved gene content and order with other vertebrate mitogenomes. The length of the 22 tRNA genes ranges between 60 bp (tRNA-Ser) and 75 bp (tRNA-Leu). The D-loop region is 1553 bp long with low CG content (39.8%).

Ultrasonic and superfast: Design constraints on echolocation in bats

Recent work from our group demonstrates that two exceptional characteristics of bat biosonar—bats’ extremely high call emission rates and these calls’ ultrasonic frequencies—reflect biomechanical constraints of the vocal apparatus. We hypothesized that smaller bats, with their smaller mouths, emit higher frequencies to achieve sufficiently directional sonar beams, and that variable directionality is critical for bats. We found that six aerial hawking, vespertilionid bat species produced sonar beams of similar shape and volume, and we predict that many bats adjust their acoustic field of view to suit habitat and task. We speculate that sonar beam shape has been an evolutionary constraint on echolocation and explains the bat size-call frequency correlation. During the terminal phase of an aerial hawking attack on an insect, bats produce a “buzz,” increasing information update rates by producing >160 calls/second. We discovered that bats use specialized superfast muscles to power these rapid call rates. We a...

Impact of the Processes of Total Testicular Regression and Recrudescence on the Epididymal Physiology of the Bat Myotis nigricans (Chiroptera: Vespertilionidae).

Myotis nigricans is a species of vespertilionid bat, whose males show two periods of total testicular regression within the same annual reproductive cycle in the northwest São Paulo State, Brazil. Studies have demonstrated that its epididymis has an elongation of the caudal portion, which stores spermatozoa during the period of testicular regression in July, but that they had no sperm during the regression in November. Thus, the aim of this study was to analyze the impact of the total testicular regression in the epididymal morphophysiology and patterns of its hormonal regulation. The results demonstrate a continuous activity of the epididymis from the Active to the Regressing periods; a morphofunctional regression of the epididymis in the Regressed period; and a slow recrudescence process. Thus, we concluded that the processes of total testicular regression and posterior recrudescence suffered by M. nigricans also impact the physiology of the epididymis, but with a delay in epididymal response. Epididymal physiology is regulated by testosterone and estrogen, through the production and secretion of testosterone by the testes, its conduction to the epididymis (mainly through luminal fluid), conversion of testosterone to dihydrotestosterone by the 5α-reductase enzyme (mainly in epithelial cells) and to estrogen by aromatase; and through the activation/deactivation of the androgen receptor and estrogen receptor α in epithelial cells, which regulate the epithelial cell morphophysiology, prevents cell death and regulates their protein expression and secretion, which ensures the maturation and storage of the spermatozoa.

C-heterochromatin and NORs distribution in karyotypes of three vespertilionid bat species from Turkey

AbstractThe chromosomal banding analysis of the karyotypes of Turkish populations of Eptesicus serotinus, Nyctalus lasiopterus and Barbastellus barbastellus was performed with the use of C-banding and Ag-NOR staining. The results obtained in E. serotinus and N. lasiopterus were congruent with previous data reported from other regions. The karyotype of E. serotinus (2n = 50, NF = 52) contained a moderate amount of centromeric C-heterochromatin and a single NOR was localized in an acrocentric autosomal pairs. The karyotype of N. lasiopterus (2n = 42, NF = 54) contained a higher amount of centromeric C-heterochromatin and the NORs were localized in two autosomal pairs. The karyotype of B. barbastellus was standard in its general characteristics (2n = 32, NF = 54, low amount of C-heterochromatin) but the NOR was localized in only one acrocentric autosomal pair. In studies from other regions, the NORs were recognized in all five acrocentric autosomal pairs of the complement of B. barbastellus.

Impact of the processes of testicular regression and recrudescence in the prostatic complex of the bat Myotis nigricans (Chiroptera: Vespertilionidae).

Myotis nigricans is a species of vespertilionid bat, whose males show two periods of total testicular regression during the annual reproductive cycle in the northwest São Paulo State, Brazil. Thus, the aim of this study was to investigate the impact of total testicular regression on the prostatic morphophisyology and its regulation. The prostatic complex (PC) of animals from the four periods of the reproductive cycle (active, regressing, regressed, and recrudescence) was analyzed by different histological, morphometric, and immunohistochemical procedures to characterize its variations, analyze its hormonal regulation and evaluate whether the prostate is affected by the processes of testicular regression and recrudescence. The results indicated a decrease in the prostatic parameters from the active to regressed periods, which are related to decreases in the testicular production of testosterone and in the prostatic expression of androgen receptor (AR), estrogen receptor α (ERα) and aromatase. However, in regressed-recrudescence periods, the prostatic expression of AR, ERα and aromatase increased, indicating the reactivation of the PC. Despite this, the PC appears to have a slower reactivation and seems not to follow the testicular recrudescence in morphological and morphometric terms. With these data, we demonstrate that the prostatic physiology is directly affected by total testicular regression and conclude that it is regulated by testosterone and estrogen, via the production of testosterone by the testes, its conversion to dihydrotestosterone by 5α-redutase and to estrogen by aromatase, and the activation/deactivation of AR and ERα in epithelial cells, which regulate cell expression and proliferation.

Sex-Specific Seasonal Change in Body Mass in Two Species of Vespertilionid Bats

In most mammals, reproductive cost differs between males and females in timing and duration because of the different sex-specific energy allocation strategies to maximize fitness. The differences in reproductive strategy adopted by sexes may result in differences in seasonal variation of body mass. Here seasonal variations in body mass are discussed for two species of vespertilionid bats: Daubenton's bat (Myotis daubentonii) and Savi's pipistrelle (Hypsugo savii). Both species were observed to have a seasonal variability in body conditions, which was sex dependent. In late spring and for a given forearm length, females were heavier than males, but differences were small in late summer. Furthermore, female'’s body mass decreased during late spring and summer likely to support the energy requirement for lactation, while male's mass did not change (H. savii) or slightly increase (M. daubentonii) over the same period. On the contrary male M. daubentonii depleted body fat reserves during early autumn, likely because of the energy expenditure to increase mating opportunities. Our results suggest that seasonal changes in body condition in hibernating bats may reflect the differences in reproductive strategies between sexes.

Insectivorous Bats Digest Chitin in the Stomach Using Acidic Mammalian Chitinase

The gastrointestinal tract of animals is adapted to their primary source of food to optimize resource use and energy intake. Temperate bat species mainly feed on arthropods. These contain the energy-rich carbohydrate chitin, which is indigestible for the endogenous enzymes of a typical mammalian gastrointestinal tract. However, the gastrointestinal tract of bat species should be adapted to their diet and be able to digest chitin. We hypothesized that (i) European vespertilionid bat species have the digestive enzyme chitinase and that (ii) the chitinolytic activity is located in the intestine, as has been found for North American bat species. The gastrointestinal tracts of seven bat species (Pipistrellus pipistrellus, Plecotus auritus, Myotis bechsteinii, Myotis nattereri, Myotis daubentonii, Myotis myotis, and Nyctalus leisleri) were tested for chitinolytic activity by diffusion assay. Gastrointestinal tracts of P. pipistrellus, P. auritus, M. nattereri, M. myotis, and N. leisleri were examined for acidic mammalian chitinase by western blot analysis. Tissue sections of the gastrointestinal tract of P. pipistrellus were immunohistochemically analyzed to locate the acidic mammalian chitinase. Chitinolytic activity was detected in the stomachs of all bat species. Western blot analysis confirmed the acidic mammalian chitinase in stomach samples. Immunohistochemistry of the P. pipistrellus gastrointestinal tract indicated that acidic mammalian chitinase is located in the stomach chief cells at the base of the gastric glands. In conclusion, European vespertilionid bat species have acidic mammalian chitinase that is produced in the gastric glands of the stomach. Therefore, the gastrointestinal tracts of insectivorous bat species evolved an enzymatic adaptation to their diet.

Ultrastructural characteristics of the spermatogenesis during the four phases of the annual reproductive cycle of the black myotis bat, Myotis nigricans (Chiroptera: Vespertilionidae)

Myotis nigricans is an endemic species of vespertilionid bat, from the Neotropical region, that resembles temperate zone bats in their reproductive cycle; presenting an annual reproductive cycle with two periods of testicular regression, which are not linked to the apoptotic process and seems to be not directly linked to any seasonal abiotic variation. Thus, this study aimed to ultrastructurally evaluate their reproductive cycle. The process of testicular regression could be divided into four periods: active; regressing; regressed and recrudescence; with all presenting distinct characteristics. The active period was similar to that of other bats, presenting the complete occurrence of spermatogenesis, with three main types of spermatogonia (A(d), A(p), and B) and 12 steps in spermatid differentiation; however, it differed in having the outer dense fibers 1, 5, 6, and 9 larger than the others. These three types of spermatogonia undergo considerable morphologic changes from regressing to the regressed period, and in the recrudescence, they return to the basic morphology, which reactivates spermatogenesis. In conclusion, our study described the process of spermatogenesis, the ultrastructure of the spermatozoa and the distinct morphologic variations in the ultrastructure of the testicular cells of M. nigricans during the four different periods of its annual reproductive cycle.

Evidence for Two Karyotypic Variants of the Lesser Horseshoe Bat (Rhinolophus hipposideros, Chiroptera, Mammalia) in Central Europe

Three different diploid chromosome numbers (2n = 54, 56 and 58) have been reported in the lesser horseshoe bat, Rhinolophus hipposideros. Asia Minor and the Middle East are inhabited by R. hipposideros specimens with 58 chromosomes. In Europe, specimens with 56 chromosomes have been recorded from several localities in the Czech Republic, Slovakia, Italy and Greece. Up to now, specimens with 54 chromosomes have been reported only from Spain and possibly from Switzerland. With the record of 54 chromosomes in specimens from Germany presented here, the distributional area of this variant is expanded into Central Europe. According to the cytogenetic data presently available, we presume that the European R. hipposideros population is divided into a western form (from Spain to Germany) with a 2n = 54 karyotype and an eastern form (from the Czech Republic to Greece) with a 2n = 56 karyotype. This study presents banded karyotypes for the 2n = 54 and 2n = 56 variants for the first time. In addition, chromosomal arm homology to the vespertilionid bat species Myotis myotis revealed by chromosome painting is reported. Whether the variants could represent separate species is also discussed.

Fossils come in to land

Fossils found in rocks of the Ediacaran period in Australia have been previously characterized as early marine organisms. But a report suggests that these rocks are fossilized soils. So did some of these Ediacaran organisms in fact live on land, like lichens? A palaeontologist and a geologist weigh up the evidence. See Letter p.89 The smaller the bat, the higher the frequency of its echolocation calls. Until now this scaling has been attributed either to the bat's size or to the supposition that smaller bats seeking finer prey will need to use higher frequencies to pick out smaller objects. But that doesn't explain why small bats emit such high-pitched squeaks—up to 55 kHz, when 20 kHz would do the job, carry farther and take less effort to produce. Annemarie Surlykke and colleagues compare echolocation signals from six species of vespertilionid bat over a fivefold mass range. They show that the size–frequency relationship is governed by the need to maintain a focused, highly directional beam. As sound beams narrow with increasing emitter size and signal frequency, smaller mouths impose a constraint that forces smaller bats to use higher frequencies to achieve a sufficiently narrow beam. Exceptions prove the rule: phyllostomid bats show a much weaker correlation between size and frequency, but they emit sounds through specialized nasal structures, not through the mouth, and noseleaf dimensions do not scale with body size.