Hipposideros Caffer Research Articles

The neglected continuously emerging Marburg virus disease in Africa: A global public health threat.

Severe viral hemorrhagic fever (VHF) is caused by Marburg virus which is a member of the Filoviridae (filovirus) family. Many Marburg virus disease (MVD) outbreaks are reported in five decades. A major notable outbreak with substantial reported cases of infections and deaths was in 2022 in Uganda. The World Health Organisation (WHO) reported MVD outbreak in Ghana in July 2022 following the detection of two probable VHF patients there. Further, the virus was reported from two other African countries, the Equatorial Guinea (February 2023) and Tanzania (March 2023). There have been 35 deaths out of 40 reported cases in Equatorial Guinea, and six of the nine confirmed cases in Tanzania so far. Data particularly on the several MVD outbreaks as reported from the African countries were searched on various databases including the Pubmed, Scopus, and Web-of-science. Also, the primary data and reports from health agencies like the WHO and the Centers for Disease Control and Prevention CDC)were evaluated and the efficacy reviewed. Chiroptera in general and bat species likeRousettus aegyptiacus and Hipposideros caffer in particular are natural reservoirs of the Marburg virus. MVD-infected nonhuman primate African fruit-bat and the MVD-infected humans pose significant risk in human infections. Cross-border viral transmission and its potential further international ramification concerns raise the risk of its rapid spread and a potential outbreak. Occurrence of MVD is becoming more frequent in Africa with higher case fatality rates. Effective prophylactic and therapeutic interventions to counter this deadly virus are suggested. In the face of the lack of effective therapeutics and preventives against MVD, supportive care is the only available option which contributes to the growing concern and disease severity. In view of the preventive approaches involving effective surveillance and monitoring system following the "One Health"model is extremely beneficial to ensure a healthy world for all, this article aims at emphasizing several MVD outbreaks, epidemiology, zoonosis of the virus, current treatment strategies, risk assessments, and the mitigation strategies against MVD.

Inventaire préliminaire des Chiroptères réservoirs des infections en République de Guinée : Boké, Conakry, Faranah, Mamou, Kindia et N’zérékoré

The aim of this work is to make a preliminary inventory of chiropteran reservoirs of infection in the Republic of Guinea: Boké, Conakry, Faranah, Mamou, Kindia and N'zérékoré. The study was conducted from January 1, 2016 to December 31, 2019. One thousand chiropterans were captured with fishing nets, mist nets or by hand and divided into 18 species and 6 families. Identification was based on the reference collection of IRBAG, Rosevear DR, Hayman RW and Bergmans W.The most representatives were: Hipposideros caffer (15.5%), Mops condylurus (10.8%), Nycteris hispida (7.7%), Neoromicia guineensis (6.8%), Hipposideros jonesi (6.3%), Chaerephon nigeriae (4, 9%), Rhinolophus guineensis (4.2%), Chaerephon pumillus (3.3%), Eidolon helvum (2.6%), Epomophorus gambianus (1.9%), Hipposideros abae (1.3%). On the other hand, the least encountered are: Scotophilus diganii (0.8%), Lissonycteris angolensis (0.7%), Rhinolophus alcyone (0.5%), Rousettus aegyptiacus (0.4%), Scotophilus leucogaster (0.4%) and Neoromicia brunnea (0.2%). These species represent the bulk of the chiropterans fauna, which may play an epidemiological or predatory role for crops and harvests.

Surveillance, Isolation, and Genetic Characterization of Bat Herpesviruses in Zambia.

Bats are of significant interest as reservoirs for various zoonotic viruses with high diversity. During the past two decades, many herpesviruses have been identified in various bats worldwide by genetic approaches, whereas there have been few reports on the isolation of infectious herpesviruses. Herein, we report the prevalence of herpesvirus infection of bats captured in Zambia and genetic characterization of novel gammaherpesviruses isolated from striped leaf-nosed bats (Macronycteris vittatus). By our PCR screening, herpesvirus DNA polymerase (DPOL) genes were detected in 29.2% (7/24) of Egyptian fruit bats (Rousettus aegyptiacus), 78.1% (82/105) of Macronycteris vittatus, and one Sundevall's roundleaf bat (Hipposideros caffer) in Zambia. Phylogenetic analyses of the detected partial DPOL genes revealed that the Zambian bat herpesviruses were divided into seven betaherpesvirus groups and five gammaherpesvirus groups. Two infectious strains of a novel gammaherpesvirus, tentatively named Macronycteris gammaherpesvirus 1 (MaGHV1), were successfully isolated from Macronycteris vittatus bats, and their complete genomes were sequenced. The genome of MaGHV1 encoded 79 open reading frames, and phylogenic analyses of the DNA polymerase and glycoprotein B demonstrated that MaGHV1 formed an independent lineage sharing a common origin with other bat-derived gammaherpesviruses. Our findings provide new information regarding the genetic diversity of herpesviruses maintained in African bats.

MHC class II genes mediate susceptibility and resistance to coronavirus infections in bats.

Understanding the immunogenetic basis of coronavirus (CoV) susceptibility in major pathogen reservoirs, such as bats, is central to inferring their zoonotic potential. Members of the cryptic Hipposideros bat species complex differ in CoV susceptibility, but the underlying mechanisms remain unclear. The genes of the major histocompatibility complex (MHC) are the best understood genetic basis of pathogen resistance, and differences in MHC diversity are one possible reason for asymmetrical infection patterns among closely related species. Here, we aimed to link asymmetries in observed CoV (CoV-229E, CoV-2B and CoV-2Bbasal) susceptibility to immunogenetic differences amongst four Hipposideros bat species. From the 2072 bats assigned to their respective species using the mtDNA cytochrome b gene, members of the most numerous and ubiquitous species, Hipposideros caffer D, were most infected with CoV-229E and SARS-related CoV-2B. Using a subset of 569 bats, we determined that much of the existent allelic and functional (i.e. supertype) MHC DRB class II diversity originated from common ancestry. One MHC supertype shared amongst all species, ST12, was consistently linked to susceptibility with CoV-229E, which is closely related to the common cold agent HCoV-229E, and infected bats and those carrying ST12 had a lower body condition. The same MHC supertype was connected to resistance to CoV-2B, and bats with ST12 were less likely be co-infected with CoV-229E and CoV-2B. Our work suggests a role of immunogenetics in determining CoV susceptibility in bats. We advocate for the preservation of functional genetic and species diversity in reservoirs as a means of mitigating the risk of disease spillover.

Marburg Virus Disease – A Mini-Review

Marburg virus disease (MVD) is a highly fatal disease caused by the Marburg virus (MARV) which belongs to the family Filoviridae. The disease has been recently reported from Ghana, an African country, and nearly 15 outbreaks of MVD have been reported in the past five decades. Various species of bats viz., Rousettus aegyptiacus, Hipposideros caffer, and certain Chiroptera act as the natural source of infection. Pathophysiology of the disease reveals severe antiviral suppression due to changes in gene expression and interferon-stimulated gene (ISG) production in the hepatic cells. With the progression of the disease, there may be the development of pain in the abdomen, nausea, vomition, pharyngitis, and diarrhea along with the onset of hemorrhagic manifestations which may lead to the death of a patient. The advent of molecular detection techniques and kits viz., reverse transcription polymerase chain reaction (RT-PCR) kit has greatly aided in the diagnosis of MVD. Identification of the virus in the specimen with great accuracy can be done by whole viral genome sequencing. The use of a combination of MR-186-YTE (monoclonal antibody) and an antiviral drug named remdesivir in the NHP model is greatly effective for eliminating MARV. The protective effect of a Vesicular stomatitis virus (VSV) (recombinant) - based vaccine expressing the glycoprotein of MARV has been revealed through animal model studies, other vaccines are also being developed. Proper health education, personal hygiene and precautions by health care workers while handling patients, good laboratory facilities and service along with the establishment of enhanced surveillance systems are the need of the hour to tackle this highly fatal disease. This article presents an overview of different aspects and salient features of MARV / MVD, and prevention and control strategies to be adopted.

African bats in the collection of the National Museum, Prague (Chiroptera). I. Bats from Zambia

A list of 139 specimens of bats belonging to 32 species of eight families originating from Zambia, housed in the collection of the National Museum, Prague, Czech Republic, is presented in a systematical review. The species lists are complemented by comments on distribution and morphometry data. The specimens represent 73 new records (species vs. locality) of bats from Zambia. The collection contains two species new for the Zambian fauna, Afropipistrellus grandidieri and Neoromicia somalica. Two species, Rhinolophus sakejiensis and Chaerephon bivittatus are documented for the second time from Zambia, the former bat for the first time after the species description at all. The record localities of Epomophorus labiatus, Rhinolophus mossambicus, and Neoromicia somalica shift margins of the whole known distribution ranges of these bats. In Epomophorus dobsonii, Nyctinomus aegyptiacus, Glauconycteris variegata, Pipistrellus rusticus, Scotophilus leucogaster, and S. viridis, the collection specimens represent new peripheral records making their distribution range margins more precise. Molecular genetic analysis revealed new distribution extent of particular mitochondrial lineages of the otherwise common species in Zambia, Hipposideros caffer, Nycteris thebaica, and Miniopterus natalensis s.str.

Diversity and activity rate of a bat communities in a voluntary nature reserve in the Agneby-Tiassa region (South-East, Côte d’Ivoire)

In order to provide basic data on the specific diversity of bats in a private forest of fifty hectares, located in the Agnéby-Tiassa region (South-eastern Côte d'Ivoire), a study was carried out there from August 26 to October 15, 2018. This was conducted in three types of habitats represented by a forest, a wetland and an edge zone. Sixty-three individuals were captured using mist nets during 38 days, from 18h00 to midnight. Twelve species of bats belonging to nine genera and five families have been inventoried. This community is dominated by Epomops buettikoferi, Scotonycteris zenkeri, Nanonycteris veldkampi, Macronycteris gigas, Hipposideros caffer and Mops thersites. The activity study has shown that Microchiroptera are most active from 18h30 to 20h while bats' activity is most intense from 21h30 to 23h00. The forest, the wetland and the edge zone are respectively the most diversified in species of bats. Epomops buettikoferi, Nanonycteris veldkampi and Hipposideros caffer activities are positively correlated with forest and edge zone while Macronycteris gigas, Mops thersites, Scotophilus nux and Eidolon helvum have a greater affinity for the wetland.

Concordant patterns of genetic, acoustic, and morphological divergence in the West African Old World leaf‐nosed bats of the Hipposideros caffer complex

en

Next-Generation Sequencing on Insectivorous Bat Guano: An Accurate Tool to Identify Arthropod Viruses of Potential Agricultural Concern.

Viruses belonging to the Dicistroviridae family have attracted a great deal of attention from scientists owing to their negative impact on agricultural economics, as well as their recent identification as potential aetiological agents of febrile illness in human patients. On the other hand, some Dicistroviruses are also studied for their potential biopesticide properties. To date, Dicistrovirus characterized in African mainland remain scarce. By using High-Throughput Sequencing technology on insectivorous bat faeces (Hipposideros Caffer) sampled in a cave used by humans to collect bat guano (bat manure) as fertilizer in Zimbabwe, we characterized the full-length sequences of three Dicistrovirus belonging to the Cripavirus and Aparavirus genus: Big Sioux River Virus-Like (BSRV-Like), Acute Bee Paralysis Virus (ABPV), and Aphid Lethal Paralysis Virus (ALPV). Phylogenetic analyses of ORF-1 and ORF-2 genes showed a complex evolutionary history between BSRV and close viruses, as well as for the Aparavirus genus. Herewith, we provide the first evidence of the presence of Dicistrovirus in Zimbabwe and highlight the need to further document the impact of such viruses on crops, as well as in beekeeping activities in Zimbabwe which represent a crucial source of income for Zimbabwean people.

Bat species diversity and distribution in a disturbed regime at the Lake Bogoria National Reserve, Kenya

AbstractHuman population growth drives intrusion and progressive conversion of natural habitats for agriculture. We evaluated human impacts on bat species diversity and distribution among four vegetation types in and around Lake Bogoria National Reserve between November 2012 and July 2013. Plants were surveyed using the Braun–Blanquet cover/abundance method, whereas bats were sampled using standard mist nets erected on poles at ground level. Floristic similarity analysis revealed three broad vegetation assemblages, namely riverine vegetation, farmland and Acacia woodland/Acacia–Commiphora woodland. Two hundred and 33 bats representing eleven species in eleven genera and seven families were recorded. These were Epomophorus minimus, Rhinolophus landeri, Hipposideros caffer, Cardioderma cor, Lavia frons, Nycteris hispida, Chaerephon pumilus, Mops condylurus, Neoromicia capensis, Scotoecus hirundo and Scotophilus dinganii. Species richness estimators indicated that sampling for bats at ground level was exhaustive. Bat species richness and diversity were highest in the more structurally complex Acacia woodland compared to more homogenous farmlands where we recorded only common and generalist species that often occur in open habitats. The higher bat species richness and diversity in the Acacia woodland as compared to farmland underscore the importance of remnant natural savannah woodlands in the conservation of bats and other elements of biodiversity.

Bat flies (Diptera: Nycteribiidae and Streblidae) infesting cave-dwelling bats in Gabon: diversity, dynamics and potential role in Polychromophilus melanipherus transmission

BackgroundEvidence of haemosporidian infections in bats and bat flies has motivated a growing interest in characterizing their transmission cycles. In Gabon (Central Africa), many caves house massive colonies of bats that are known hosts of Polychromophilus Dionisi parasites, presumably transmitted by blood-sucking bat flies. However, the role of bat flies in bat malaria transmission remains under-documented.MethodsAn entomological survey was carried out in four caves in Gabon to investigate bat fly diversity, infestation rates and host preferences and to determine their role in Polychromophilus parasite transmission. Bat flies were sampled for 2–4 consecutive nights each month from February to April 2011 (Faucon and Zadie caves) and from May 2012 to April 2013 (Kessipoughou and Djibilong caves). Bat flies isolated from the fur of each captured bat were morphologically identified and screened for infection by haemosporidian parasites using primers targeting the mitochondrial cytochrome b gene.ResultsAmong the 1,154 bats captured and identified as Miniopterus inflatus Thomas (n = 354), Hipposideros caffer Sundevall complex (n = 285), Hipposideros gigas Wagner (n = 317), Rousettus aegyptiacus Geoffroy (n = 157, and Coleura afra Peters (n = 41), 439 (38.0 %) were infested by bat flies. The 1,063 bat flies recovered from bats belonged to five taxa: Nycteribia schmidlii scotti Falcoz, Eucampsipoda africana Theodor, Penicillidia fulvida Bigot, Brachytarsina allaudi Falcoz and Raymondia huberi Frauenfeld group. The mean infestation rate varied significantly according to the bat species (ANOVA, F(4,75) = 13.15, P < 0.001) and a strong association effect between bat fly species and host bat species was observed. Polychromophilus melanipherus Dionisi was mainly detected in N. s. scotti and P. fulvida and less frequently in E. africana, R. huberi group and B. allaudi bat flies. These results suggest that N. s. scotti and P. fulvida could potentially be involved in P. melanipherus transmission among cave-dwelling bats. Sequence analysis revealed eight haplotypes of P. melanipherus.ConclusionsThis work represents the first documented record of the cave-dwelling bat fly fauna in Gabon and significantly contributes to our understanding of bat fly host-feeding behavior and their respective roles in Polychromophilus transmission.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-016-1625-z) contains supplementary material, which is available to authorized users.

Isolation and characterization of 11 novel microsatellite loci in a West African leaf-nosed bat, Hipposideros aff. ruber.

BackgroundNoack’s leaf-nosed bat, Hipposideros ruber, is a cryptic species within the Hipposideros caffer species complex. Despite a widespread distribution in Africa and being host to potentially zoonotic viruses, the genetic structure and ecology of H. ruber is poorly known. Here we describe the development of 11 novel polymorphic microsatellite loci to facilitate the investigation of genetic structure.FindingsWe selected 20 microsatellite sequences identified from high throughput sequence reads and PCR amplified these for 38 individuals, yielding 11 consistently amplifying and scorable loci. The number of alleles per locus ranged from two to 12, and observed heterozygosities from 0.00 to 0.865. No evidence of linkage disequilibrium was observed, and nine of the markers showed no departure from Hardy-Weinberg equilibrium. We demonstrate successful amplification in two closely related species and two divergent lineages of the H. caffer species complex.ConclusionsThese new markers will provide a valuable tool to investigate genetic structure in the poorly understood Hipposideros caffer species complex.

Trypanosoma livingstonei: a new species from African bats supports the bat seeding hypothesis for the Trypanosoma cruzi clade

BackgroundBat trypanosomes have been implicated in the evolutionary history of the T. cruzi clade, which comprises species from a wide geographic and host range in South America, Africa and Europe, including bat-restricted species and the generalist agents of human American trypanosomosis T. cruzi and T. rangeli.MethodsTrypanosomes from bats (Rhinolophus landeri and Hipposideros caffer) captured in Mozambique, southeast Africa, were isolated by hemoculture. Barcoding was carried out through the V7V8 region of Small Subunit (SSU) rRNA and Fluorescent Fragment Length barcoding (FFLB). Phylogenetic inferences were based on SSU rRNA, glyceraldehyde phosphate dehydrogenase (gGAPDH) and Spliced Leader (SL) genes. Morphological characterization included light, scanning and transmission electron microscopy.ResultsNew trypanosomes from bats clustered together forming a clade basal to a larger assemblage called the T. cruzi clade. Barcoding, phylogenetic analyses and genetic distances based on SSU rRNA and gGAPDH supported these trypanosomes as a new species, which we named Trypanosoma livingstonei n. sp. The large and highly polymorphic SL gene repeats of this species showed a copy of the 5S ribosomal RNA into the intergenic region. Unique morphological (large and broad blood trypomastigotes compatible to species of the subgenus Megatrypanum and cultures showing highly pleomorphic epimastigotes and long and slender trypomastigotes) and ultrastructural (cytostome and reservosomes) features and growth behaviour (when co-cultivated with HeLa cells at 37°C differentiated into trypomastigotes resembling the blood forms and do not invaded the cells) complemented the description of this species.ConclusionPhylogenetic inferences supported the hypothesis that Trypanosoma livingstonei n. sp. diverged from a common ancestral bat trypanosome that evolved exclusively in Chiroptera or switched at independent opportunities to mammals of several orders forming the clade T. cruzi, hence, providing further support for the bat seeding hypothesis to explain the origin of T. cruzi and T. rangeli.

Hipposideros caffer (Chiroptera: Hipposideridae)

Hipposideros caffer (Sundevall, 1846) is a hipposiderid bat commonly called Sundevall's leaf-nosed or roundleaf bat. H. caffer is a medium-sized insectivorous bat with a horseshoe-shaped nose leaf and 2 color phases in adulthood. It is 1 of 67 species in the genus Hipposideros and is found in the southwestern Arabian Peninsula, in most of Africa south of the Sahara (excluding the central forested region), and in Morocco, Zanzibar, and Pemba. H. caffer is a savanna-dwelling species and inhabits a variety of roost types including caves, hollow trees, and abandoned buildings. It often roosts in groups of thousands of individuals, is very common, and is not of special conservation concern.

Variation of mitochondrial DNA in the Hipposideros caffer complex (Chiroptera: Hipposideridae) and its taxonomic implications

The Afrotropical leaf-nosed bat Hipposideros caffer has been traditionally regarded as a complex of populations, currently pertaining to two recognized cryptic species, H. caffer and H. ruber. Extent of distribution and morphological variation of these bats has raised concerns over whether the current perception of the complex reflects true phylogenetic relationships and taxonomic diversity. Our phylogenetic analysis of nucleotide sequences of the mitochondrial cytochrome b gene challenged the hypothesis of two cryptic species. Instead of the two reciprocally monophyletic lineages expected, corresponding to the two species, we recovered four distinct lineages with deep internal divergences. Two sister clades within a lineage of bats of H. caffer represent respectively the nominotypical form H. c. caffer, restricted to Southern Africa, and H. c. tephrus, inhabiting the Maghreb, West Africa and the Arabian Peninsula. Geographical isolation and deep genetic divergence suggest species status of both the forms. Another lineage comprises specimens of both morphotypes from West and East Africa. It probably represents a distinct species but its taxonomic assignation remains obscure. A Central African lineage of H. ruber comprises two sister clades, which become sympatric in Cameroon. Their status has to be clarified with additional evidence, since nuclear gene flow might be taking place. A further divergent lineage with H. ruber morphotype, most probably representing another distinct species, is restricted to West Africa. Although all three genetic forms of H. ruber may correspond to named taxa, their proper taxonomic assignation has to be assessed by comparison with type material.

Absent or Low Rate of Adult Neurogenesis in the Hippocampus of Bats (Chiroptera)

Bats are the only flying mammals and have well developed navigation abilities for 3D-space. Even bats with comparatively small home ranges cover much larger territories than rodents, and long-distance migration by some species is unique among small mammals. Adult proliferation of neurons, i.e., adult neurogenesis, in the dentate gyrus of rodents is thought to play an important role in spatial memory and learning, as indicated by lesion studies and recordings of neurons active during spatial behavior. Assuming a role of adult neurogenesis in hippocampal function, one might expect high levels of adult neurogenesis in bats, particularly among fruit- and nectar-eating bats in need of excellent spatial working memory. The dentate gyrus of 12 tropical bat species was examined immunohistochemically, using multiple antibodies against proteins specific for proliferating cells (Ki-67, MCM2), and migrating and differentiating neurons (Doublecortin, NeuroD). Our data show a complete lack of hippocampal neurogenesis in nine of the species (Glossophaga soricina, Carollia perspicillata, Phyllostomus discolor, Nycteris macrotis, Nycteris thebaica, Hipposideros cyclops, Neoromicia rendalli, Pipistrellus guineensis, and Scotophilus leucogaster), while it was present at low levels in three species (Chaerephon pumila, Mops condylurus and Hipposideros caffer). Although not all antigens were recognized in all species, proliferation activity in the subventricular zone and rostral migratory stream was found in all species, confirming the appropriateness of our methods for detecting neurogenesis. The small variation of adult hippocampal neurogenesis within our sample of bats showed no indication of a correlation with phylogenetic relationship, foraging strategy, type of hunting habitat or diet. Our data indicate that the widely accepted notion of adult neurogenesis supporting spatial abilities needs to be considered carefully. Given their astonishing longevity, certain bat species may be useful subjects to compare adult neurogenesis with other long-living species, such as monkeys and humans, showing low rates of adult hippocampal neurogenesis.

Bat species diversity and distribution in three vegetation communities of Meru National Park, Kenya

AbstractDiversity and distribution of bats was determined in four vegetation types in and around Meru National Park, Kenya between September 2000 and February 2001. Bat‐habitat studies were based on plant species dominance, cover and farming activities. Bats were captured using standard mist nets (18 m long × 2 m high) erected on poles averaging 3 m. Vegetation was broadly grouped as Acacia or Combretum wooded grassland, or Acacia–Commiphora bushland and studied using the Braun‐Blanquet method. Analysis of floristic similarity showed five vegetation species assemblages in the three broad categories. Four hundred and ninety‐five bats representing eleven genera in seven families were recorded. These were Epomophorus labiatus, E. wahlbergi, Cardioderma cor, Lavia frons, Myotis welwitschii, Scotoecus hirundo, S. leucogaster, Pipistrellus kuhlii, Mops condylurus, Chaerephon bemmeleni, Mormopterus sp., Hipposideros caffer, H. commersoni, Nycteris arge and Rhinolophus landeri. This was the first record of N. arge, M. welwitschii, C. bemmeleni and a Mormopterus species in eastern Kenya. The Combretum community was most equitable (E = 0.51) with nine bat species records, while farming areas had only four. The low species richness and increased dominance of a few generalist species on farms may be indicative of different levels of disturbance.

A long‐term ecological survey of bats (Mammalia, Chiroptera) in the Eastern Niger Delta (Nigeria)

The structure of bat assemblages was studied in relation to variation in forest landscapes in four localities of the eastern Niger Delta (southern Nigeria). The study areas were inhabited by thirteen species, seven Megachiroptera and six Microchiroptera, among which Eidolon helvum, Hypsignathus monstrosus, Rousettus egyptiacus, Saccolaimus peli, and Hipposideros caffer were recorded for the first time, whereas Epomophorus gambianus, Scotonycteris zenkeri, Megaloglossus woermanni, Scotophilus viridis, and Mops thersites were first cited only recently. The majority of captures occurred in secondary forest habitat (99 specimens belonging to 10 species), followed by primary forest (40 specimens, 5 species), and by the bush (13 specimens, 5 species). A multivariate set of analyses arranged the various species into six ‘ecological groups’: (i) Eidolon helvum, Mops thersites; (ii) Hipposideros caffer, (iii) Hypsignathus monstrosus; (iv) Rousettus egyptiacus, Epomops franqueti, Scotonycteris zenkeri, Nycteris arge, (v) Saccolaimus peli, Scotophilus viridis, Nycteris hispida; (vi) Epomophorus gambianus, Megaloglossus woermanni. The various groups are interpreted in the light of the available information on the ecology and distribution of Nigerian bats.

Resource use by two morphologically similar insectivorous bats (Nycteris thebaicaandHipposideros caffer)

Studies of morphologically dissimilar insectivorous bats have lead to the conclusion that morphology is the prime correlate of habitat use, and consequently of diet. This has lead to the prediction that morphologically similar bats should have similar diets. We examined the diet and morphology of two morphologically similar species, the slit-faced bat, Nycteris thebaica, and Sundevall's leaf-nosed bat, Hipposideros caffer, in the context of this prediction. Although both species foraged in the same habitat, they had distinctly different diets. The diet of N. thebaica consisted mainly of non-volant prey, primarily orthopterans and arachnids, and the diet of H. caffer, mainly of moths. Differences in wing design between the two taxa were small. The only significant difference was in aspect ratio. There were no differences in wing loading and wingtip shape ratio between the two species. The flying abilities reported for these two species are very similar, suggesting that these small differences in wing design do not translate into differences in flying ability, and cannot explain the dietary differences between these two species. On the other hand, there are marked differences in their prey detection systems which correspond to differences in their diets. H. caffer uses echolocation to detect the flapping wings of insect prey, whereas N. thebaica depends on prey-generated sounds (fluttering or scuffling) to locate its targets.

Predation upon Moths by Free-Foraging Hipposideros caffer

Predation upon insects by the bat Hipposideros caffer was studied at Skukuza in the Kruger National Park of South Africa. These bats, whose echolocation calls are inaudible to moths, fed overwhelmingly upon tympanate Lepidoptera, although insects of other orders frequently dominated the local light-responsive, flying, nocturnal insect community. The relative numbers of noctuid, pyralid, and arctiid moths taken by the bats were proportional to the representation of these families in the general population of moths, but they took disproportionately fewer moths of the family Geometridae. The bats also ate significantly fewer arctiid moths of those species capable of clicking than of those species that could not. Because the arctiids could not hear approaching H. caffer , these moths did not click before contact with an attacking bat, and their clicks could not protect them by interfering with echolocation by the predators. These results are consistent with the startle and acoustic-aposematism hypotheses for the bat-protective function of arctiid clicks.