1,721,145 research outputs found
NATURAL HISTORY AND LARVAL MORPHOLOGY OF BOOPHIS OCCIDENTALIS (ANURA: RANIDAE: RHACOPHORINAE) PROVIDE NEW INSIGHTS INTO THE PHYLOGENY AND ADAPTIVE RADIATION OF ENDEMIC MALAGASY FROGS
No full textFIGURE 2 in Pretty in pink: A new treefrog species of the genus Boophis from North-Eastern Madagascar
No full textFIGURE 2. Life colouration of B. ulftunni. The photos show specimens from I, Masoala, II, Tsararano, IIIa, Marojejy (ZSM 80/2005; IIIb, ventral view), and IVa, Anjanaharibe-Sud (IVb, ventral view).Published as part of Wollenberg, K. C., Andreone, F., Glaw, F. & Vences, M., 2008, Pretty in pink: A new treefrog species of the genus Boophis from North-Eastern Madagascar, pp. 58-68 in Zootaxa 1684 (1) on page 63, DOI: 10.11646/zootaxa.1684.1.3, http://zenodo.org/record/510694
FIGURE 4 in Pretty in pink: A new treefrog species of the genus Boophis from North-Eastern Madagascar
No full textFIGURE 4. Maximum-likelihood tree of 13 Boophis species including B. ulftunni sp. n. Numbers on nodes indicate bootstrap values higher than 50% in MP (first numbers) and ML tree searches (second numbers).Published as part of Wollenberg, K. C., Andreone, F., Glaw, F. & Vences, M., 2008, Pretty in pink: A new treefrog species of the genus Boophis from North-Eastern Madagascar, pp. 58-68 in Zootaxa 1684 (1) on page 66, DOI: 10.11646/zootaxa.1684.1.3, http://zenodo.org/record/510694
FIGURE 1 in Pretty in pink: A new treefrog species of the genus Boophis from North-Eastern Madagascar
No full textFIGURE 1. Specimens of Boophis ulftunni sp. n. I. male holotype from Masoala (MRSN A4287); II. male paratype from Masoala (MRSN A2562); III. male specimen from Marojejy (ZSM 80/2005); IV. female specimen from Anjanaharibe-Sud (MRSN A4449). Scale represents 10 mm.Published as part of Wollenberg, K. C., Andreone, F., Glaw, F. & Vences, M., 2008, Pretty in pink: A new treefrog species of the genus Boophis from North-Eastern Madagascar, pp. 58-68 in Zootaxa 1684 (1) on page 62, DOI: 10.11646/zootaxa.1684.1.3, http://zenodo.org/record/510694
Chromosome aneupolyploidy in an endemic Malagasy gecko (Gekkonidae: Geckolepis)
No full textPolyploidy is exceptional in mammals and rare in reptiles. Unscheduled polyploidy often leads to cell disorders and cancer through genomic rearrangements that can be difficult to trace and is particularly poorly studied in non-model vertebrates. In the present paper, using a combination of banding and Fluorescence In Situ Hybridization (FISH) techniques, we reconstruct and characterize the origin and significance of aneupolyploid karyotypes found in the bone marrow of an individual of the Malagasy gecko Geckolepis typica. Our results demonstrate that these anomalous karyotypes correspond to a proliferative cell disorder characterized by a succession of distinct structural events, from a preliminary duplication of the whole genome to the instability of loci of NORs and subsequent chromosome rearrangements that will produce aneuploid cells. Our comparison between the newly described normal, i.e., diploid, karyotype of the species (2n = 40) and aneutetraploid plates (4n = 77–80) revealed that translocations of NOR-bearing chromosomes are involved in generating aneuploidy. Furthermore, simultaneous and multiple translocations of the NOR-bearing chromosomes occurred with relatively high frequency (27% and 19%, respectively) on distinct chromosome pairs. In addition, in about 9% of 90 scored metaphase plates, structural instability of the NOR regions also produced detachments of rDNA arrays and generated an accessory, fully heterochromatic B-chromosome. Our data suggest that the duplication of the whole genome can be considered a preliminary stage in proliferative cell disorders, inducing chromosomal instability and structural rearrangements. © 2018 Deutsche Gesellschaft für Herpetologie und Terrarienkunde e.V. (DGHT), Mannheim, Germany
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Changes in heterochromatin content and ancient chromosome fusion in the endemic malagasy boid snakes sanzinia and acrantophis (Squamata: Serpentes)
No full textKaryological evolution and systematics of Malagasy microhylid frogs
No full textMicrohylid frogs are a group of largely unresolved phylogeny, and diverse data sets are needed to improve the evolutionary understanding of these amphibians. We here report karyological data for 22 species of this family, belonging to the Malagasy genera Anodonthyla, Cophyla, Platypelis, Plethodontohyla, Rhombophryne, and Stumpffia (Cophylinae); Scaphiophryne and Paradoxophyla (Scaphiophryninae); and Dyscophus (Dyscophinae); and the Asian genera Calluella and Ramanella (Microhylinae). All species studied have 2n = 26 chromosomes, most of which are metacentric or submetacentric. Chromosome morphology, banding pattern, and position of the nucleolar organizer regions (NORs) provide relevant characters for the understanding of the phylogeny and systematics of these frogs. The species of the Cophylinae are characterized by a subtelocentric or telocentric fourth chromosome pair (submetacentric only in Anodonthyla), which can be seen as a synapomorphy for this subfamily. Shifts in NOR position within the Cophylinae are frequent and agree with recent mitochondrial DNA data, corroborating the non-monophyly of the genus Plethodontohyla. Changes of NOR position and chromosome morphology (i.e., occurrence of subtelocentric and telocentric elements) were also common in this subfamily, possibly being related to their faster mitochondrial substitution rate and high species diversity. The ninth chromosome pair of the examined specimens of Dyscophus guineti, all juveniles, is heteromorphic. In this pair, one of the two chromosomes is longer due to the addition of two heterochromatic segments, raising the possibility that one chromosome of this pair may be a sex chromosome. (C) 2007 Elsevier GmbH. All rights reserved
The discovery of a candidate new species in Eastern Madagascar helps clarify some aspects of Cophylinae (Anura: Microhylidae) taxonomy
No full textBetampona Strict Nature Reserve, located on the east coast of Madagascar, incorporates a small fragment of the once continuous lowland rainforest. Here, a recent herpetological survey revealed an astonishing amphibian diversity, confirming the occurrence of at least 76 taxa, 36 of which were classified as candidate new species. Several of these candidates belong to the endemic subfamily Cophylinae Cope, 1889. The cophylines have a complex history of taxonomic revision and recent molecular findings have identified a large taxonomic gap in this group. Among these candidate new species, one taxon was tentatively named Plethodontohyla sp. aff. brevipes [Ca FJ559294] (or P. sp. Ca03). After a closer examination of the recently collected specimens and a careful comparison with museum vouchers we found that this taxon is conspecific with Phrynocara laeve Boettger, 1913. Ph. laeve was described based on one
specimen collected at Sakana (Eastern Madagascar) in September 1904 by A. Voeltzkow, later synonymized with Dyscophus alluaudi Mocquard, 1901 (currently considered a member of the genus Rhombophryne) by Blommers-Schlösser and Blanc, 1991. This finding shows that Phrynocara laeve is not synonymous with R. alluaudi, being instead a valid species of the genus Plethodontohyla
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