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The average genome size (GS) of bats, which are the only mammals capable of powered flight, is approximately 18% smaller than that of closely related mammalian orders. The low nuclear DNA content of Chiroptera is comparable to that of birds, which are also characterized by a high metabolic rate. Only a few chiropteran taxa possess notable amounts of constitutive heterochromatin. Here, we studied the karyotypes of two non-related vesper bat species with unusually high amounts of constitutive heterochromatin: Hesperoptenus doriae and Philetor brachypterus. Conventional staining methods and whole-chromosome painting with probes derived from Myotis myotis (2n = 44), showing a karyotype close to that of the presumed ancestor of Vespertilionidae, revealed Robertsonian fusions as the main type of rearrangement leading to the exceptionally reduced diploid chromosome number of 2n = 26 in both species. Moreover, both karyotypes are characterized by large blocks of pericentromeric heterochromatin composed of CMA-positive and DA-DAPI-positive segments. In H. doriae, the heterochromatin accumulation has resulted in a genome size of 3.22 pg (1C), which is 40% greater than the mean genome size for the family. For P. brachypterus, a genome size of 2.94 pg was determined, representing an increase of about 28%. Most notably, in H. doriae, the presence of additional constitutive heterochromatin correlates with an extended mitotic cell cycle duration in vitro. A reduction in diploid chromosome number to 30 or lower is discussed as a possible cause of the accumulation of pericentromeric heterochromatin in Vespertilionidae. [ABSTRACT FROM AUTHOR]

East Africa is a hotspot of biodiversity of many orthopteran taxa, including bushcrickets. Gonatoxia Karsch, 1889 species are fully alate Phaneropterinae, which are perfectly adapted to the foliage of forests. We examined five species using combined cytogenetic and molecular data to determine the inter- and intraspecific genetic diversity. The variation in the diploid number of chromosomes in males ranged from 2n = 28 + X0 and 26 + X0 to 2n = 6 + X0. Fluorescence in situ hybridization showed from one to many 18S rDNA loci as well as interstitial sequences, especially in G. helleri. 18S rDNA loci coincided with active NOR and C-banding patterns. The isolation of populations of the species explains differences in the number of chromosomes (G. maculata), chromosomal polymorphism and chromosomal heterozygosity (G. helleri). Our molecular phylogeny based on the COI locus supported the monophyly of the genus Gonatoxia and separateness of the five examined species in accordance with their morphological features and chromosome numbers as well as the species' distribution. [ABSTRACT FROM AUTHOR]

East African mountains constitute a network of isolated habitat islands among dry savannah and are thus ideal for studying species diversification processes. This study elucidated the phylogenetic and phylogeographic relationships of all bushcricket species comprising the genus Aerotegmina. Our analysis indicated that large-scale climatic and topographic processes in Africa are likely to have driven speciation in this group, and revealed the cytogenetic traits of the species. Molecular phylogeny supported the monophyly of Aerotegmina and showed that the genus probably originated in the old Eastern Arc Mountains of Tanzania and Kenya. Two lineages were distinguished: small- and large-sized species with geographically distinct habitats. The underlying processes are thought to be eight dispersals, ten vicariance events, and one extinction event linked to repeated fragmentation of the African rainforest. Those processes, in conjunction with habitat change, probably also led to the spatial separation of the species into a northern clade with a diploid number of chromosomes 2n = 32 + X0 or 2n = 30 + neo-XY and a southern clade with a reduced number of chromosomes (2n = 28 + X0 or 24 + neo-X1X2Y). Karyotype analysis suggests that Aerotegmina is currently in the process of speciation. [ABSTRACT FROM AUTHOR]

Acoustic communication is an essential part of the mate-finding system of many insects, e.g., ensiferan Orthoptera. In this group, the signals consist typically of relatively simple repetitive sound patterns produced for long times and used by the females for a phonotactic approach to the singing males. However, the situation can be different in duetting species where the females respond acoustically to the male. Here, we present data of the songs of 14 East African species of the duetting genus Eurycorypha. These songs are extremely diverse differing in many parameters and containing up to three different syllable types grouped into various echemes. In the duets between males and females, studied in 7 species, the females respond with latency times between 100 and 400 ms and are in some species able to react to different trigger syllables or also to the end of a series of syllables. The males often modify their songs after having heard a female response. Some of these modifications are also produced spontaneously. Similar elements are even found as integral part of the calling song in some species. We interpret these modifications aimed to protect a duet against eavesdropping rivals and thus as part of intrasexual selection. The evolution of the complicated song patterns may thus be driven by the interaction between female choice s.l. and male-male competition. [ABSTRACT FROM AUTHOR]

In katydids (Orthoptera: Tettigonioidea) of the subfamily Phaneropterinae females ready to mate initiate a duet, announcing her position to the male singer, but also potentially to eavesdropping rivals. In many species the male seems to defend the communication by adding self-produced imitations of a female response. If these signals occur within the male sensory time-window after the female song, they can disturb the orientation of rivals. In two species of the genus Gonatoxia, males and females use short, relatively narrow-banded sounds (width 2-7 kHz 10 dB below peak). Male song and female response, however, differ considerably in peak frequency. In G. maculata, the peak frequency of the last part of the male song (13 kHz) is between that of the first part (15 kHz) and the female response (9 kHz), in G. helleri the last part (9 kHz; assumed imitation) and the female song are identical in peak frequency and by a factor two lower than the first part (19 kHz). The male stridulatory file of this species is correspondingly modified and differs from all other members of the genus. The imitation of spectral properties of the female response is not known from any other katydid. [ABSTRACT FROM AUTHOR]

The East African species of Parapyrrhicia Brunner von Wattenwyl, 1891, are reviewed. Beside the description of five new species from the West Usambara, Udzungwa, Uluguru Mountains, and coastal Tanzania and the male of P. zanzibarica Brunner von Wattenwyl, 1891, data on habitat, morphology, acoustics, and the chromosomes are provided. A key to the species of Parapyrrhicia is provided. Eulioptera zanzibarica Brunner von Wattenwyl, 1891, is synonymized with Parapyrrhicia zanzibarica Brunner. All species have stridulatory files with intertooth intervals decreasing from anal to basal and low duty cycle calling songs (four species recorded) consisting of very short, narrow-banded, resonant syllables. Parapyrrhicia species showed a plesiomorphic karyotype with a diploid chromosome number of 2 n = 31 and a X0 sex chromosome system in males. All species are restricted to closed wet forest areas and thus ideal organisms to be used for monitoring habitat quality of an area since they act as indicators for indigenous wet forest communities. Morphological sister pairs suggest recent speciation processes in coastal and lowland wet forests of East Africa. [ABSTRACT FROM AUTHOR]

The genus Tettigonia includes 26 species distributed in the Palaearctic region. Though the Green Bush-crickets are widespread in Europe and common in a variety of habitats throughout the Palaearctic ecozone, the genus is still in need of scientific attention due to the presence of a multitude of poorly explored taxa. In the present study, we sought to clarify the evolutionary relationships of Green Bush-crickets and the composition of taxa occurring in the Western Palaearctic. Based on populations from 24 disjunct localities, the phylogeny of the group was estimated using sequences of the cytochrome oxidase subunit I (COI) and the internal transcribed spacers 1 and 2 (ITS1 and ITS2). Morphological and acoustic variation documented for the examined populations and taxa was interpreted in the context of phylogenetic relationships inferred from our genetic analyses. The trees generated in the present study supported the existence of three main lineages: 'A'-composed of all sampled populations of Tettigonia viridissima and the Tettigonia vaucheriana complex, 'B'-comprising Tettigonia caudata, Tettigonia uvarovi, and the Tettigonia armeniaca complex, and 'C'-consisting of Tettigonia cantans. The present study provides the first phylogenetic foundation for reviewing the systematics of Tettigonia (currently classified mostly according to morphological characteristics), proposing seven new synonymies. [ABSTRACT FROM AUTHOR]

In most bushcricket species, the male transfers a nuptial gift to the female during mating, consisting of a gelatinous spermatophylax attached to the paired ampulla with the sperm. The spermatophylax acts as a sperm protection device; during its consumption, the sperm are transferred into the female's spermatheca. Males of the bushcricket Letana inflata (Brunner von Wattenwyl, 1878) show strongly extended copulation duration. When the pair finally separates, only an ampulla is visible at the females' genital opening, but no spermatophylax. To better understand copulation dynamics in the absence of a spermatophylax, we studied copula duration and sperm transfer pattern. Our results show that in Letana inflata the missing spermatophylax is replaced by extended copulation, securing the transfer of sperm into the spermatheca. [ABSTRACT FROM AUTHOR]

In the mate recognition system of bush-crickets (Tettigonioidea) two character complexes are most important: acoustic communication for long-distance attraction and genital fitting during the actual mating process. Here we describe these both components for Letana inflata, a species of the subfamily Phaneropterinae in which the females typically do not approach the singing males phonotactically but respond with their own acoustical signals to the male song. In this duet males and females use extremely short signals. As a calling song the males produce mainly one single loud impulse of less than one millisecond duration, which is answered by the female after about half a second again only with one or up to three short loud impulses. Male and female signals have similar carrier frequencies, although their stridulatory organs are not homologous and possess different forms. When mating, males and females engage in an unusually prolonged copulation which lasts more than three hours. Most phaneropterine species studied before mate for less than four minutes. The long duration may be related to the presence of a titillator (phallic sclerite), not present in most phaneropterines studied so far, and a very unusually shaped male subgenital plate which allows the male a stable hold of the female ovipositor. Already 30-60 min after beginning of the copulation the males were found to carry the sperm-containing ampulla inside their body with the tip of the ampulla being in contact with the female genital opening. The mating behavior is discussed especially in comparison with the other tettigonioid species with prolonged copulation. [ABSTRACT FROM AUTHOR]

The Plangia graminea complex is partly reviewed and two new species of Plangia are described, Plangia multimaculata n. sp. from savanna habitats and Plangia satiscaerulea n. sp. from the submontane zones in northern Tanzania. Plangia compressa (Walker 1869) is synonymized with P. graminea (Serville, 1838). Data on habitat, bioacoustics, and chromosomes are provided. Both analyzed Plangia species showed the same chromosomal number. Compared to other investigated African Phaneropterinae, Plangia had a reduced chromosome number and thus shows a derived condition in its genome. The sex chromosomes differed morphologically in both investigated species of Plangia suggesting different mechanisms leading to these differences. Niche specialization and the male calling song are discussed as drivers for speciation in fully alate and thus mobile taxa. [ABSTRACT FROM AUTHOR]

The flightless Agraeciini genus Afroanthracites, a genus restricted to East Africa, is reviewed and two new species are described. Exemplary for the genus Afroanthracites, the ecological niche of Afroanthracites montium from Mt Kilimanjaro is defined. A. montium occupies habitats in humid and perhumid conditions and thus shows a broad altitudinal range (1250-2700 m). Concerning the acoustic communication, it is remarkable that within the micropterous genus a trend to low carrier frequencies is observed combined with the evolution of larger stridulatory organs (mirror; resonating part of tegmen). This trend starts with species using the same ultrasonic frequencies as a brachypterous out-group and ends with species presenting clearly audible songs. Cytogenetic data are given for five Afroanthracites and one Afroagraecia species. Differences in chromosome numbers Afroanthracites 2 n = 29 and Afroagraecia 2 n = 27 as well as a number of major rDNA clusters (one and two, respectively) are probably useful markers to separate both genera. It is discussed whether the African species evolved from a species with a presumably derived karyotype (e.g. 27 or 29 chromosomes) or if the proposed reduction of chromosome number occurred independently in Africa, Asia and Australia. The data set suggests that the African Agraeciini is of monophyletic origin, with a common ancestor of Afroagraecia and Afroanthracites in Africa. The Afroanthracites species can be divided into three groups on base of their morphology and colour pattern. Species of adjacent areas are morphologically sister groups. The most derived forms as seen in their morphology and acoustics are found in the West Usambara Mountains, part of the geologically old Eastern Arc Mountains. [ABSTRACT FROM AUTHOR]

The genus Aerotegmina Hemp is common on East African mountains. Two species are known and a third, A. taitensis n. sp., is described in this paper. A. kilimandjarica Hemp is widespread while A. shengenae Hemp is endemic to the South Pare Mountains and A. taitensis n. sp. is known only from the Taita Hills. Morphologically, and from their song, A. shengenae and A. taitensis n. sp. are closely related. In chromosome number A. kilimandjarica (2 n = 33) differs clearly from A. shengenae (2 n = 27). Data presented on other flightless Orthoptera suggest that the South Pare Mountains and the Taita Hills, both belonging to the geologically old mountain chain of the Eastern Arc, show a faunistic similarity not shared by any other mountain range in the area. The mechanisms that led to this phylogeographic pattern in flightless Orthoptera in the Eastern Arc Mountains of northern Tanzania and southern Kenya and the inland volcanoes are discussed. A key to the three Aerotegmina species is presented, as well as bioacoustical data of all species compared to the phaneropterine species Euryastes jagoi. [ABSTRACT FROM AUTHOR]

Although Eurycorypha is the most species-rich Phaneropterinae genus in Africa, little is known about the distribution and the ecology of the species. In this study data on distribution, ecology, song and on chromosomes of some East African species are provided. The nymphs of some species are shown, famous for their ant-like appearance and behaviour. The male of E. punctipennis Chopard and three species of Eurycorypha are newly described. These are E. resonans n. sp. and E. combretoides n. sp. occurring in different habitats on Mount Kilimanjaro, and E. conclusa n. sp from forest habitats along the Tanzanian coast. Bioacoustically, the four recorded species are unusually divers, presenting non-resonant and resonant songs. As four Eurycorypha species occur syntopically on geological young Mount Kilimanjaro, the biogeographical pattern and possible speciation mechanisms in the genus Eurycorypha are discussed in context of the climatical history of eastern Africa. [ABSTRACT FROM AUTHOR]

A new genus is proposed for a new East African Phaneropterinae species, Lunidia viridis, occurring on Mt. Kilimanjaro, Tanzania. Based on 33 records, notes on distribution and habitat are given, as well as acoustical data provided. Climate and vegetation parameters obtained along several transects on Mt. Kilimanjaro were evaluated describing the ecological niche of the new species. This interdisciplinary approach allows not only a profound characterisation of the ecological demands of the new genus but also predictions of the potential distribution area, which is tested for the first time for an African bush cricket species. Lunidia viridis n. gen. n. sp. occurs within humid and perhumid forests and Chagga home gardens, avoiding subhumid conditions on the mountain. It is found from 1,330 m upwards on the southern slopes, whereas the same ecological conditions are expressed from 1,930 m upwards on the drier northern slopes. Lunidia viridis has an unusually complex and variable song, which is described from field and laboratory recordings. The FISH technique for characterizing chromosomes is applied for the first time for an African species; L. viridis exhibits a karyotype typical for most Tettigoniidae. [ABSTRACT FROM AUTHOR]

In the Constant Frequency portions of the orientation calls of various Rhinolophus and Hipposideros species, the frequency with the strongest amplitude was studied comparatively. (1) In the five European species of the genus Rhinolophus call frequencies are either species-specific ( R. ferrumequinum, R. blasii and R. euryale) or they overlap ( R. hipposideros and R. mehelyi). The call frequency distributions are approximately 5-9 kHz wide, thus their ranges spead less than ±5% from the mean (Fig. 1). Frequency distributions are considerably narrower within smaller geographic areas. (2) As in other bat groups, call frequencies of the Rhinolophoidea are negatively correlated with body size (Fig. 3). Regression lines for the genera Rhinolophus and Rhinolophus, species from dryer climates have on the average higher call frequencies than species from tropical rain forests. (4) The Krau Game Reserve, a still largely intact rain forest area in Malaysia, harbours at least 12 syntopic Rhinolophus and Hipposiderso species. Their call frequencies lie between 40 and 200 kHz (Fig. 2). Distribution over the available frequency range is significantly more even than could be expected from chance alone. Two different null hypotheses to test for random character distribution were derived from frequency-size-relations and by sampling species assemblages from a species pool (Monte Carlo method); both were rejected. In particular, call frequencies lying close together are avoided (Figs. 4, 5). Conversely, the distribution of size ratios complied with a corresponding null hypothesis. This even distribution may be a consequence of resource partitioning with respect to prey type. Alternatively, the importance of these calls as social signals (e.g. recognition of conspecifics) might have necessitated a communication channel partitioning. [ABSTRACT FROM AUTHOR]

Males of most bushcricket species produce acoustic advertisement signals to attract females for mating. These signals can also increase conspicuousness to predators. In the genus Poecilimon (Orthoptera: Phaneropterinae) males are attacked by the parasitoid fly Therobia leonidei (Diptera: Tachinidae: Ormiini) which locates males by their calls. In Greece T.leonidei parasitizes several Poecilimon species with different song structures: we examined whether host choice is related to song structure by comparing parasitism rates in two closely related Poecilimon species. One of these species produces monosyllabic songs, the songs of the other species being polysyllabic. The tachinid fly parasitized the polysyllabic species to a greater extent. We demonstrate in a field-experiment that this preference for the polysyllabic species does not depend on local adaptations of the fly. The most probable explanation for the preference of the fly for the polysyllabic singing species seems to be better detection of longer songs. This result is discussed in the context of male song evolution. [ABSTRACT FROM AUTHOR]