Cynopterus Sphinx Research Articles

Record of bats and their echolocation calls from southern Dolakha, central Nepal

Abstract With 52 species, bats make up almost a quarter of all the mammal species in Nepal, and yet remains the least understudied group of mammals. Owing to its diverse geography and climate, more species of bats potentially occur in the country, and acoustic surveys could improve the knowledge of their ecology. So, a study was conducted in Sailung and Melung Rural Municipalities of Dolakha district of Nepal, with the objectives of assessing bat species richness and preparing digital records of their echolocation calls. Using mist-netting and roost survey during three periods in 2018 (late March, late May to early June and mid-November), 10 species of bats were recorded: Cynopterus sphinx, Lyroderma lyra, Rhinolophus ferrumequinum, Rhinolophus luctus, Rhinolophus pearsonii, Rhinolophus sinicus, Hipposideros armiger, Myotis formosus, Myotis sp. and Nyctalus noctula. Ten roosts (mostly caves) were located. Echolocation calls of six of these species were documented, including signals of three species described for the first time in Nepal. This study also reports the fifth record of Myotis formosus in Nepal and new locality record of the species after two decades. The echolocation calls documented hereafter may serve as a reference for species identification for non-invasive studies of bats.

Multimodal cues facilitate ripe-fruit localization and extraction in free-ranging pteropodid bats

Sensory cues play an important role in any plant―animal interaction. Yet, we know very little about the cues used by wild mammals during fruit selection. Existing evidence mainly comes from captive studies and suggests that the pteropodid bats rely on olfaction to find fruits. In this study, we avoided captivity-generated stressors and provide insights from natural selective forces by performing manipulative experiments on free-ranging fruit bats (Cynopterus sphinx) in a wild setting, in a tree species that exhibits a bat-fruit syndrome (Madhuca longifolia var. latifolia). We find that visual cues are necessary and sufficient to locate ripe fruits. Fruit experiments exhibiting visual cues alone received more bat visits than those exhibiting other combinations of visual and olfactory cues. Ripe fruit extractions were higher by bats that evaluated fruits by perching than hovering, indicating an additional cue, i.e., haptic cue. Visual cues appear to be informative over short distances, whereas olfactory and haptic cues facilitate the fruit evaluation for those bats that used hovering and perching strategies, respectively. This study also shows that adult bats were more skillful in extracting ripe fruits than the young bats, and there was a positive correlation between the weight of selected fruits and bat weight. This study suggests that the integration of multimodal cues (visual, olfactory and haptic) facilitate ripe-fruit localization and extraction in free-ranging pteropodid bats.

Sex differences in postprandial blood glucose and body surface temperature are contingent on flight in the fruit bat, Cynopterus sphinx.

ABSTRACTThe postprandial blood glucose level is very high for the body size in frugivorous bats. Like other homeotherms, bats release heat during digestion of dietary macronutrients. Despite males and females of the same species exhibiting different foraging behaviour, empirical support for sex differences in blood glucose and body surface temperature in fruit bats is poor. Moreover, while flight affects postprandial metabolism, whether such effects are different in each sex of fruit bats is unclear. Here, we studied these questions in the fruit bat, Cynopterus sphinx. We first assessed whether there are sex differences in the postprandial level of blood glucose and body surface temperature over time in rested bats. We then assessed whether flight affects outcomes of sex differences in both traits. We found that the estimated marginal means of both traits were generally higher in females than males, in rested bats. Notably, the sex difference in both traits was only significant at specific sampling time of the assay. Further, the trait means significantly differed between the sexes only in the rested, but not active, bats, meaning that signals of sex difference in metabolic traits eroded when bats were active. Taken together, our findings suggest that in C. sphinx, the sex specificity in the expression of metabolic traits is significantly dependent on physical activity.

A review of the breeding biology of Chiroptera

Abstract Since 2000, no reviews or analyses have been carried out on scientific studies regarding bat reproductive biology. Such reviews might contribute towards identifying information gaps and global research focus and trends. The objective of this work was to review and analyse scientific studies on different aspects of bat reproduction published in the last two decades (2000–2019), in order to provide perspective for future research. Using 19 key words, we searched for literature on the reproduction of bats published as book chapters and articles in scientific research journals globally. We analysed 36 chapters in 14 books and 276 scientific articles, from 41 countries, identifying publishing trends throughout the years, preferred journals, countries in which studies have been carried out, and most‐studied species and topics. The number of studies increased over the last decade, resulting from the consolidation of research lines in countries such as Brazil, India, Mexico, and USA. The studies covered 125 species, of which Scotophilus heathi and Cynopterus sphinx were the most recurrent, each appearing in 23 studies (7.4%, n = 312). The most common subject was anatomy (61 studies, 20%, n = 312), and the rarest was assisted reproduction techniques (11 studies, 3.5%, n = 312). In the last decade, there has been a trend to increase the study of male anatomy. The application of new techniques for the study of reproduction contributed to more complex studies that favour the understanding of the reproductive process. There is an evident lack of reproductive studies for most species, and there is an information gap regarding research in prenatal development and assisted reproduction techniques. These two topics are greatly significant for future research, because of their direct usefulness for species conservation.

The first mitochondrial genome data of an old world fruit bat, Cynopterus sphinx from Malaysia

We assembled the complete mitogenome of Cynopterus sphinx (Vahl, 1797) of the family Pteropodidae originating from Malaysia. The total mitogenome size was 16,710bp which consists of 37 genes (13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and one control region). A phylogenetic and BLASTn result showed the mitogenome sequence in this study varies by nearly 7% (93.48% similarity) from the same species in Cambodia. The next closest match of BLASTn was at 92% similarity to the C. brachyotis. This suggests the species-complex in Cynopterus sp. has given rise to the genetic variability.

Light, flight and the night: effect of ambient light and moon phase on flight activity of pteropodid bats.

Fruit-feeding pteropodid bats roost under varying light conditions. Some roost in trees with high exposure to daylight (> 1000lx), while others roost in dark caves (< 0.1lx). To understand the effect of ambient light intensity and moon phase on flight activity, we examined flight times across five lunar cycles in three pteropodid species whose roosts differ in daylight exposure. We found significant interspecific differences in flight emergence and termination times. All species initiated flights after sunset but Rousettus leschenaultii, which typically roosts in caves, delayed emergence (40 ± 11min) more than the two tree-roosting species Pteropus giganteus (16 ± 6min) and Cynopterus sphinx (19 ± 7min). R. leschenaultii terminated flights earlier (30 ± 7min before sunrise) than P. giganteus (11 ± 11min) and C. sphinx (16 ± 10min). All individuals from P. giganteus and C. sphinx roosts emerged within less than an hour, while emergence times were more spread out in the R. leschenaultii colony. Peak emergence times differed across moon phases in the cave-roosting R. leschenaultii but not in the other species. Flight activity in R. leschenaultii is restricted to comparatively lower light levels than the tree-roosting species. The observed interspecific differences suggest that bat species, sharing same landscapes may respond differently to light pollution.

Morphometric and Phylogenetic Analysis of Short-Nosed Fruit Bat Cynopterus sphinx (Vahl, 1797) Captured from Fata Regions, Pakistan

Morphometric and Phylogenetic Analysis of Short-Nosed Fruit Bat Cynopterus sphinx (Vahl, 1797) Captured from Fata Regions, Pakistan

Rat‐ and bat‐pollination of Mucuna championii (Fabaceae) in Hong Kong

AbstractMucuna (Fabaceae) species possess gullet‐type flowers that open explosively and which are thought to be specifically adapted for bat‐ or bird‐pollination. However, recent studies have shown that non‐flying mammals are also important pollinators of this genus in Asia. Here we report on the pollination system of Mucuna championii (endemic in southeast China) in Hong Kong. As is typical for the genus, explosive opening is essential for fruit set, but flowers are unable to open in the absence of manipulation by an effective pollinator. Camera trap surveys of three individuals revealed both chestnut spiny rats (Niviventer fulvescens) and short‐nosed fruit bats (Cynopterus sphinx) to be capable of triggering explosive opening. The number of flowers opened by each species did not differ significantly, and both removed most pollen grains from the flowers they visited, but either species visited different individuals. Sucrose‐rich nectar was secreted by flowers throughout the day. Our results reveal that M. championii can be pollinated by both rats and bats, with this representing only the second report of rat‐pollination in tropical Asia. The sympatric M. birdwoodiana often occurs in close proximity to M. championii and has an overlapping flowering season, suggesting that pollinator segregation may have played a role in shaping the evolutionary ecology of these two species.

First distributional record of short-nosed fruit bat &lt;em&gt;Cynopterus sphinx&lt;/em&gt; (Vahl, 1797) (Chiroptera: Pteropodidae) from Dhubri district of Assam, Northeast India

First distributional record of short-nosed fruit bat &lt;em&gt;Cynopterus sphinx&lt;/em&gt; (Vahl, 1797) (Chiroptera: Pteropodidae) from Dhubri district of Assam, Northeast India

The role of pteropodid bats in pollination of durian (Durio zibethinus) in managed orchards in suburban habitat of Thailand

Pollination specialists are increasingly threatened worldwide, especially in intensively-managed durian orchards where loss of pollinators may lead to reduced fruit production. In tropical plant communities where plant species attract multiple species of pollinators, specialists may have advantages over generalists. The present study examined the pollination ecology of durian (Durio zibethinus) in intensively and non-intensively managed orchards in suburban habitats of Nakhon Nayok and Chanthaburi provinces, respectively, in Thailand. Manual-pollination yielded the greatest fruit set 60 d after pollination, followed by open pollination (mostly by pteropodid bats), and insect pollination, while non-pollinated flowers had no fruit set. Eonycteris spelaea was the major bat pollinator in both provinces. Bats found in suburban habitat of Nakhon Nayok were mostly Eonycteris spelaea (67%). Pollen of at least five plant species was found on Eonycteris spelaea fur, including Musa sp., Oroxylum indicum, Durio zibethinus, Bombax valetonii and an unknown species. Pollen of only two species, Oroxylum indicum and Musa sp., was observed on Cynopterus sphinx fur. The non-intensive orchards in Nakhon Nayok, where mixed-species gardens are maintained under more naturalistic conditions, might offer higher fruit set on average. Such conditions might maintain higher bats capture rate of natural pollinators and reduce the risk of pollination failure in comparison with intensively-managed durian orchards.

Role of putrescine in ovary and embryo development in fruit bat Cynopterus sphinx during embryonic diapause.

The aim of this study was to evaluate the effect of putrescine on ovarian activity and the rate of embryonic development in Cynopterus sphinx during delayed development. The result showed the presence of a rate-limiting enzyme, ornithine decarboxylase-1, in both ovary and utero-embryonic unit of C. sphinx suggests a synthesis of putrescine in these sites. The corpus luteum showed increased, whereas utero-embryonic unit showed decreased production of putrescine during delayed development as compared with the normal development. The bat treated in vivo with putrescine during delayed development showed increase in progesterone and estradiol synthesis, correlated with increased expression of luteinizing hormone receptor, steroidogenic acute receptor protein, and 3β-hydroxysteroid dehydrogenase through extracellular signal-regulated kinase (ERK1/2)-mediated pathway in the ovary; but showed increase in the weight and expression of progesterone receptor (PR), B-cell lymphoma 2, proliferating cell nucleus antigen, and vascular endothelial growth factor proteins in utero-embryonic unit. The in vitro treatment of putrescine showed stimulatory whereas treatment with an inhibitor of putrescine, 2-difluoromethylornithine caused an inhibitory effect on ovarian progesterone synthesis and cell proliferation, and cell survival in the utero-embryonic unit. In conclusion, the putrescine showed two separate roles during embryonic diapause, high concentration of putrescine in the ovary may support corpus luteum and basal synthesis of progesterone, whereas a low level of putrescine causes retarded embryonic development by inhibiting cell proliferation in the utero-embryonic unit. The bat treated with putrescine either directly promotes cell proliferation, cell survival, and angiogenic activities or acts indirectly increasing PR on utero-embryonic unit thereby activating development in delayed embryo in C. sphinx.

Identification of Diverse Bat Alphacoronaviruses and Betacoronaviruses in China Provides New Insights Into the Evolution and Origin of Coronavirus-Related Diseases.

Outbreaks of severe acute respiratory syndrome (SARS) in 2002, Middle East respiratory syndrome in 2012 and fatal swine acute diarrhea syndrome in 2017 caused serious infectious diseases in humans and in livestock, resulting in serious public health threats and huge economic losses. All such coronaviruses (CoVs) were confirmed to originate from bats. To continuously monitor the epidemic-related CoVs in bats, virome analysis was used to classify CoVs from 831 bats of 15 species in Yunnan, Guangxi, and Sichuan Provinces between August 2016 and May 2017. We identified 11 CoV strains from 22 individual samples of four bat species. Identification of four alpha-CoVs from Scotophilus kuhlii in Guangxi, which was closely related to a previously reported bat CoV and porcine epidemic diarrhea virus (PEDV), revealed a bat-swine lineage under the genus Alphacoronavirus. A recombinant CoV showed that the PEDV probably originated from the CoV of S. kuhlii. Another alpha-CoV, α-YN2018, from Rhinolophus sinicus in Yunnan, suggested that this alpha-CoV lineage had multiple host origins, and α-YN2018 had recombined with CoVs of other bat species over time. We identified five SARS-related CoVs (SARSr-CoVs) in Rhinolophus bats from Sichuan and Yunnan and confirmed that angiotensin-converting enzyme 2 usable SARSr-CoVs were continuously circulating in Rhinolophus spp. in Yunnan. The other beta-CoV, strain β-GX2018, found in Cynopterus sphinx of Guangxi, represented an independently evolved lineage different from known CoVs of Rousettus and Eonycteris bats. The identification of diverse CoVs here provides new genetic data for understanding the distribution and source of pathogenic CoVs in China.

Mitochondrial DNA identified bat species in northeast India: electrocution mortality and biodiversity loss

Northeast India with two biodiversity hotspots is recognized as a biodiversity-rich region. However, several extant animals including chiropterans are currently at jeopardy due to habitat loss, electrocution mortality, and other anthropogenic threats. This study examines the efficacy of mitochondrial Cytochrome b (mtCytb) sequences for species-level identification of five electrocuted bat specimens from Manipur state. The similarity search results in the global database, Kimura 2 parameter (K2P) genetic distances, and neighbor-joining (NJ) tree identified all bat specimens into two species, Cynopterus sphinx and Megaerops niphanae. The detection of M. niphanae is the first record of this mammal from the state. In comparison with other Pteropodidae species, the genetic distances clearly discriminate both C. sphinx (7.9–30.2%) and M. niphanae (12.2–25.7%). In addition, the combined tree analysis of present and earlier genetic information of C. sphinx suggested the presence of cryptic lineages and sympatric population in India. This similar approach with more sampling from a wide distribution area could assist the future genetics research on chiropterans and their precise conservation.

Report on three ectoparasites of the Greater Short-nosed Fruit Bat Cynopterus sphinx Vahl, 1797 (Mammalia: Chiroptera: Pteropodidae) in Cachar District of Assam, India

Ectoparasites of bats (Chiroptera: Pteropodidae), with a description of three species of of which two belong to order Mesostigmata (family: Ameroseiidae and Macronyssidae) and one belong to order Ixodida (family: Ixodidae), from northeastern India are discussed. The present study was carried out for six months (January–June 2014) to identify the various ectoparasites of the Short-nosed Fruit Bat Cynopterus sphinx in Cachar District of Assam, northeastern India. A total of 12 individuals of C. sphinx was captured using mist nets from eight different localities of the study area. During the study, a total of 125 parasites was collected from C. sphinx. The identified parasites were Dermacentor sp. Indet., Ameroseius sp. Indet., and Steatonyssus sp. Indet. and falls under the class Arachnida.

Responses of Short-Nosed Fruit Bat, &lt;i&gt;Cynopterus sphinx&lt;/i&gt; (Vahl 1797) Towards Distress Calls of their Conspecifics from Related and Unrelated Sites:Implications for Building a Social Relationship

Distress calls emitted by bats signal their conspecifics either to warn them or inform them about the situations. Conspecifics may also get attracted towards distress calls as a behaviour of cooperative mobbing or just selfishly assessing the potential source of danger. The exact functions of distress calls in bats therefore vary to a great degree and are very hard to pinpoint. We conducted playback experiments to test the response of short-nosed fruit bat, Cynopterus sphinx towards the distress calls of their conspecifics from related and unrelated sites. Bats were attracted to their conspecifics from both related and unrelated sites and in one occasion towards fruit bat ( Rousettus leschenaulti ) of another genus within the same family. The response towards the opposite sex was significant in most of the playback trials and the reasons remain unclear. This symmetric response towards conspecifics from related and unrelated sites suggests the possibility of fruit bats building social relationships among unrelated individuals and probably between species.

Comparative Population Structure in Species of Bats Differing in Ecology and Morphology in the Andaman Islands, India

Gene flow results from movement between populations, homogenising gene pools and impacting genetic variation and evolution. Growing evidence suggests that movement of individuals among populations may be more strongly determined by ecological traits. We compared genetic and morphometric differentiation in four species of bats — Eonycteris spelaea, Cynopterus sphinx, Rhinolophus affinis and Hipposideros pomona — which differ in their flight capability and roosting requirement to understand their effects in shaping genetic structure. Hypervariable region I of the mitochondrial control region was amplified from 40 E. spelaea, 28 C. sphinx, 44 R. affinis and 57 H. pomona sampled from locations spread across the Andaman archipelago. Populations of E. spelaea were nearly panmictic; R. affinis were differentiated into two clusters, and H. pomona were differentiated into three clusters. Consistent genetic and morphometric clusters were obtained for C. sphinx and the genetic break for C. sphinx occurs between Midd...

MiR-132 regulated olfactory bulb proteins linked to olfactory learning in greater short-nosed fruit bat Cynopterus sphinx

Earlier, we showed that micro RNA-132 (miR-132) regulate the immediate early genes (IEGs) in the olfactory bulb (OB) of fruit bat Cynopterus sphinx during olfactory learning. This study was designed to examine whether the miR-132 regulate other proteins in OB during olfactory learning. To test this, miR-132 anti-sense oligodeoxynucleotide (AS-ODN) was delivered to the OB and then trained to novel odor. The 2-dimensional gel electrophoresis analysis showed that inhibition of miR-132 altered olfactory training induced expression of 321 proteins. Further, liquid chromatography-mass spectrometry (LC-MS/MS) analysis reveals the identity of differently expressed proteins such as phosphoribosyl transferase domain containing protein (PRTFDC 1), Sorting nexin-8 (SNX8), Creatine kinase B-type (CKB) and Annexin A11 (ANX A11). Among them PRTFDC 1 showing 189 matching peptides with highest sequence coverage (67.0%) and protein-protein interaction analysis showed that PRTFDC 1 is a homolog of hypoxanthine phosphoribosyltransferase-1 (HPRT-1). Subsequent immunohistochemical analysis (IHC) showed that inhibition of miR-132 down-regulated HPRT expression in OB of C. sphinx. In addition, western blot analysis depicts that HPRT, serotonin transporter (SERT), N-methyl-d-asparate (NMDA) receptors (2A,B) were down-regulated, but not altered in OB of non-sense oligodeoxynucleotide (NS-ODN) infused groups. These analyses suggest that miR-132 regulates the process of olfactory learning and memory formation through SERT and NMDA receptors signalling, which is possibly associated with the PRTFDC1-HPRT interaction.

Seed dispersal of a tropical deciduous Mahua tree, Madhuca latifolia (Sapotaceae) exhibiting bat-fruit syndrome by pteropodid bats

Pollination and seed dispersal are two important phases of the reproductive cycle in plants and are usually performed by different groups of animal taxa in tropics. However, in Mahua tree, Madhuca latifolia (Sapotaceae) both pollination and seed dispersal are predominantly performed by pteropodid bats. We report the foraging and seed dispersal strategies of three sympatric pteropodid bats, Cynopterus sphinx, Rousettus leschenaultii and Pteropus giganteus, during two successive fruiting seasons of M. latifolia. These sympatric fruit bats exhibited spatio-temporal variation while foraging and consumed fleshy mesocarp of fruits and discarded the seeds. Fruit processing time corresponded to the size of the bat species (P. giganteus > R. leschenaultii > C. sphinx); the larger the bat, the more number of fruits they consumed. P. giganteus predominantly consumed the fruits in situ (87% of the times). However, during peak foraging hours, when intraspecific aggressive interactions were high, these bats flew away with fruits from the parent tree (13%), and transported seeds to longer distances (at a time, which they carried = 7.2 km). On the contrary, R. leschenaultii and C. sphinx plucked one fruit at a time and carried to their feeding roosts for consumption. The feeding roosts of medium-sized fruit bat R. leschenaultii were located farther than that of the small-sized C. sphinx, i.e., 52.81 m and 34.18 m, respectively. Comparison of seed germination rates showed no significant variation between bat-dispersed seeds (R. leschenaultii: 95% and C. sphinx: 90%) and control seeds (manually extracted: 90%). As intact fruits did not germinate, mesocarp removal and mobility of seeds away from the parent tree were the main advantages gained by M. latifolia from the foraging bats suggesting the existence of a resource−service mutualism between the fruit bats and bat fruits.

Coronaviruses in guano from Pteropus medius bats in Peradeniya, Sri Lanka.

SummaryBats are a unique group of mammals well suited to be hosts for emerging viruses. With current rates of deforestation and urbanization, redistribution of bat habitats to urban and suburban areas may bring bats into closer contact with livestock and humans. Common flying fox, Pteropus medius (previously known as Pteropus giganteus), forms large communal roosts on treetops, often in close proximity to human habitation in Sri Lanka. This report describes the detection of coronavirus RNA in P. medius bat guano collected in Peradeniya, Sri Lanka. These viruses had >97% nucleotide identity with coronaviruses detected in Cynopterus sphinx, Scotophilus heathii and S. kuhlii bats in Thailand. Pteropus medius is widespread in Asia and appears to excrete group D coronaviruses, which are hitherto confined to bats; however, these findings may have public health implications in the future.

Role of Melatonin in Modulation of Immune Status of Pregnant Female Indian Short Nosed Fruit Bat Cynopterus Sphinx

Pregnancy is associated with profound immunological changes that are characterized by a strong activation of certain components of the innate immune defense and a down-regulation of adaptive immune functions. This shift in balance of the immune system towards an innate dominance is thought to be important for the maintenance of pregnancy. Based on our observation in the short nosed fruit bat Cynopterus sphinx, a seasonal breeder, we show for the first time that melatonin injection to the pregnant females significantly increases lymphocyte proliferation of spleen and consequently the circulating level of lymphocytes and percent stimulation ratio of splenocytes, thereby improving immune status during pregnancy. We have reported earlier that during pregnancy melatonin level increases significantly which in turn might improve the maternal immunity. Towards establishing this inference we used a physiological dose of p-chlorophenylalanine (p-CPA), an indirect antagonist of melatonin, which reduced circulatory melatonin level and thereby reduced the immune status. It is conceived that specific immune adaptation is conveyed to the fetus through placental transfer of melatonin thereby controlling fetal immunity as well. This could be an adaptation during pregnancy to protect the mother from various external threats.