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The vespertilionid bat genus Hesperoptenus, comprising only five species and showing a distribution in the tropical regions from India to Sulawesi, was hitherto underrepresented in recent taxonomic studies. Here, modern cytogenetic techniques were applied to compare the karyotypes of two Hesperoptenus species, H. tomesi and H. blanfordi. Despite having the same chromosome number, 2n = 32, the karyotypes of H. tomesi and H. blanfordi were found to differ extensively. Instead, H. tomesi was found to share all nine derived Robertsonian fusion products with the previously published karyotype of H. doriae (2n = 26), which points to a closer relationship between both species. In line with our chromosomal data, mitochondrial DNA analyses also provided evidence for a closer relationship of H. tomesi with H. doriae and H. tickelli, for which no banded karyotype has been examined. Again, H. blanfordi was clearly separated from the remaining Hesperoptenus species. As a consequence, the subgenus Milithronycteris, comprising all species of Hesperoptenus except the type species H. doriae, is rendered paraphyletic. We therefore suggest to synonymize Milthronycteris with the subgenus Hesperoptenus. A chromosomal character, found in all three Hesperoptenus species examined but absent in other vespertilionid genera studied so far, namely a particular G-banding pattern on the homolog to Myotis chromosome MMY13, may serve as a synapomorphy for the genus Hesperoptenus. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships and species delimitation in African Vespertilionini have been a long-standing subject of debate and are still controversial, although recent molecular analyses have shed light onto some of these issues. In this study we employed a comparative cytogenetics approach for the delineation of chromosomal homology and for the detection of shared chromosomal characters, which were then used to support proposed phylogenetic relationships. Here, we present karyotype analyses of five African Vespertilionini, Laephotis kirinyaga (2n = 32), Neoromicia guineensis (2n = 26), Pseudoromicia brunnea (2n = 36), Nycticeinops happoldorum (2n = 24), and Nycticeinops schlieffenii (2n = 34), which were complemented by mitochondrial DNA sequence analysis for species classification of all our specimens. Our cytogenetic analyses revealed that three derived Robertsonian fusion chromosomes, 7/11, 8/9, and 10/12, characterize the karyotypes of four African Vespertilionini genera, i.e. Laephotis, Neoromicia, Afronycteris, and Pseudoromicia, for which we propose to constitute a new subtribe, Laephotina. A rare chromosomal rearrangement, an X-autosome translocation, was found in the studied N. guineensis female. The genus Nycticeinops is characterized by a high intrageneric karyotype diversity. In only two of all four analyzed species, i.e. N. happoldorum and N. crassulus, a common chromosomal feature, the fusion product 1/13 was detected. Further, for the recently described East African serotine, L. kirinyaga, we present the second record for West Africa. The cytochrome b sequence of our N. guineensis specimen from Ivory Coast showed 4% divergence to that of its closest relative, N. somalica from Kenya. [ABSTRACT FROM AUTHOR]

Detailed karyotype analysis including fluorescence in-situ hybridization with chromosome-specific and sub-regional probes revealed novel cytogenetic signatures for elucidating phylogenetic relationships in Vespertilionoidea. Two shared derived Robertsonian fusions characterize all members of this superfamily. Further, the majority of Molossidae species show karyotypes with 48 chromosomes, including six of seven species studied here, namely Ozimops petersi, Mormopterus jugularis, Tadarida teniotis, Mops mops, Molossus molossus and M. pretiosus. A shared derived feature of all molossid taxa studied is a variant homolog to Myotis myotis chromosome MMY22. Despite their overall similarity in karyotype composition with one large and three medium-sized bi-armed as well as 19 acrocentric to subtelocentric autosomal pairs, our detailed analysis revealed small differences which shed new light onto molossid phylogenetic relationships. Because of the retention of several ancestral chromosomal characters, O. petersi and M. jugularis represent early offshoots of the molossid tree. A unique derived paracentric inversion in the MMY6 homolog unites all other molossids studied so far. The next species to branch off is T. tadarida, followed by a group composed of M. mops and all studied New World taxa, united by a further derived inversion in the MMY5 homolog. In the light of our findings, we recommend to elevate the subspecies M. t. griseiventer to species rank, because the specimen from Venezuela with a 2n = 42 karyotype differed clearly from the nominate subspecies Molossops t. temminckii with 2n = 48. Further, karyotypes of Miniopterus and Natalus were studied. In the 2n = 46 chromosomal complement of the family Miniopteridae a large number of autapomorphic characters were found. Based on the observation of a common derived condition of the MMY22 homolog, we assume that long-winged bats (Miniopteridae) are closer related to vespertilionids than to molossids. Finally, karyotype comparison in Natalus revealed two autapomorphic characters in the 2n = 36 chromosomal complement. [ABSTRACT FROM AUTHOR]

Classical and molecular cytogenetic methods were applied to study the karyotypes of one species of Hipposideridae and three taxa of the Rhinolophidae subgenus Aquias from Malaysian Borneo. Except for four chromosomal pairs with autapomorphic arm combinations, the karyotype of Coelops robinsoni was found to be similar to the closely related Aselliscus stoliczkanus. From the three Rhinolophus taxa studied, only R. trifoliatus was found to share the karyotype with conspecifics from Peninsular Malaysia. In contrast, the karyotype of R. luctus foetidus from Sarawak, Borneo differed in the composition of the Y-autosomal translocation products from the closely related R. morio from Peninsular Malaysia, formerly also a subspecies of R. luctus. Therefore, elevation to specific rank is suggested for R. l. foetidus. Examination of the chromosomal set of male R. sedulus specimens from Borneo with 2n = 45 and a Neo-X1X2Y sex chromosome system revealed extreme differences to the karyotype of specimens from Peninsular Malaysia with 2n = 28, to date also classified as R. sedulus. Therefore, with Sarawak, Borneo, as the type locality for R. sedulus, the taxon from Peninsular Malaysia is here described as a new species. [ABSTRACT FROM AUTHOR]

The only representatives of Emballonuridae in the Neotropics are Diclidurini from the subfamily Emballonurinae. In this tribe, karyotype comparison based on G-banding patterns has revealed extensive chromosomal divergence. Here, we present for the first time a detailed karyotype analysis of a Diclidurini species, Saccopteryx bilineata (SBI), by G-banding and cross-species fluorescence in-situ hybridization (FISH) with Myotis myotis (Vespertilionidae) painting probes. The 25 evolutionarily conserved units (ECUs) ancestral to all Chiroptera were found as 37 segments on the 2n = 26 SBI karyotype. Comparison with the karyotype of another Emballonuridae (Emballonura monticola) from South-East Asia revealed a single common derived segment combination, MMY3+MMY22i, pointing to a fast karyotype evolution in Emballonurinae. [ABSTRACT FROM AUTHOR]

Two species of the monogeneric family Nycteridae were studied for the first time with chromosome banding techniques and chromosome painting. The diploid chromosome number of Nycteris macrotis and N. tragata is 40 and 38, respectively. Both karyotypes differ by a translocation, a telomeric fusion and a pericentric inversion. The genus Nycteris shows a highly derived karyotype where the 25 chiropteran evolutionarily conserved units (ECUs) are represented in 37 segments. Chromosome painting with Myotis probes revealed three common features of Nycteris and Emballonura, which are not present in Taphozous. From a cytogenetic point of view, Nycteris is therefore closer related to Emballonura than to Taphozous. Further, an additional synapomorphy for Vespertilioniformes is described, i.e. the synteny of a segment homologous to human chromosome 13 and ECU12a-22a in elements homologous to Myotis chromosome MMY6. [ABSTRACT FROM AUTHOR]

We present a comparative molecular cytogenetic investigation of six emballonurid species using chromosome banding and cross-species chromosome painting with probes from Myotis myotis, supplemented by selected probes from human, tree shrew, and lemur. The main differences between the 2n = 42 Taphozous karyotype and the 2n = 44 chromosomal complement of Saccolaimus can be explained by one Robertsonian fusion, one type-b, and one type-c whole arm reciprocal translocation. The 2n = 24 karyotype of Emballonura is highly derived by splitting of 11 of the 25 chiropteran evolutionarily conserved units resulting in a total number of 36 segments. In contrast to the presence of several autapomorphies in the karyotypes of studied species from both subfamilies, no cytogenetic synapomorphy uniting Taphozoinae and Emballonurinae was found. [ABSTRACT FROM AUTHOR]

For the majority of Rhinolophus species a karyotype consisting of either 58 or 62 chromosomes was reported. The members of the R. trifoliatus clade are therefore distinguished from other rhinolophids by low diploid chromosome numbers (2 n) and a high rate of chromosomal changes. Recently, based on cytogenetic characters, a cryptic species, R. luctoides, was described and a subspecies, R. luctusmorio, was elevated to species rank. In the present work, the karyotypes of a male bat from Vietnam and a female one from China, both classified as R. luctus by morphological characters, were studied by G-banding and fluorescence in situ hybridization with whole chromosome painting probes derived from Aselliscus stoliczkanus. In the male specimen from Vietnam, the composition of the 15 autosomal bi-armed pairs (2 n = 32, FN = 60) is identical to that of R. luctoides from Malaysia. For reason of differences in body size and baculum length as well as in skull morphology, this specimen is provisionally treated as R. cf. luctoides. The karyotype of the female specimen from Sichuan province, China, differs from R. luctoides by a whole arm reciprocal translocation resulting in an altered arm composition of pairs 3 and 4. For this reason, the elevation of the Chinese subspecies of R. luctus, i.e. R. lanosus, to species rank is suggested. The karyotype of the endemic Taiwanese species R. formosae with a diploid number of 2 n = 52 is mainly composed of acrocentric autosomal pairs. Of the five bi-armed pairs, only the two smallest show the same arm composition as found in the 2 n = 32 karyotypes of other members of the R. trifoliatus clade. The composition of the remaining three bi-armed pairs is unique and represents an apomorphic feature for R. formosae. [ABSTRACT FROM AUTHOR]

The article presents a study on genetic diversity in Rhinolophus luctus (Chiroptera: Rhinolophidae) from Peninsular Malaysia. Topics include the description of the new species Rhinolophus luctus morio based on genetic and morphological characters and morphological examination showing differences in size of the baculum and length of the lower toothrow.

Objectives: In most cases, XX or XY gonadal dysgenesis remains genetically unexplained. In this pilot study we searched for sex-chromosomal mosaicism in gonads of patients with XX or XY gonadal dysgenesis of undetermined origin. Study Design: Gonadal tissues were analyzed by cytogenetic and interphase fluorescence in-situ hybridization (FISH) analyses in four patients with gonadal dysgenesis and normal female (46,XX) or male (46,XY) karyotypes in lymphocytes. ResuLts: Cytogenetic and FISH analyses of the gonads demonstrated in three patients a sex-chromosomal mosaicism. Cytogenetic analysis of gonadal tissue of the fourth patient confirmed the result of the lymphocytes with 46,XX, but FISH analysis revealed in 17% of nuclei only one X-chromosome. Conclusion: Our data indicate that sex-chromosomal mosaicism in gonads may be a frequent cause of gonadal dysgenesis despite of normal karyotypes in lymphocytes. Therefore, cytogenetic and FISH analyses of gonadal tissue can provide important information in unexplained cases of gonadal dysgenesis. [ABSTRACT FROM AUTHOR]

The article presents an obituary for German biologist Otto Freiherr von Helversen-Helversheim.