Publications by authors named "Bjoern Stelbrink"

Article Synopsis
  • The study focuses on the diverse species flocks in ancient lakes, particularly highlighting freshwater gastropods from Sulawesi, which are known for their unique evolutionary adaptations.
  • Utilizing next-generation sequencing, researchers gathered a comprehensive dataset of mitochondrial genomes from 78 individuals, including most morphospecies of Tylomelania in the Malili lake system.
  • The findings suggest that, while mitochondrial genomes provide more data, they often behave like a single locus, limiting their effectiveness in resolving complex species relationships, especially in cases of rapid diversification and mitochondrial introgression.
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Article Synopsis
  • Extinction rates are rising, but conservation resources are limited, prompting a focus on prioritizing unique species for protection based on their evolutionary and ecological significance.* -
  • Researchers analyzed historical DNA from an old specimen of the rare snail species Helicostoa sinensis, revealing its unique evolutionary traits and confirming its classification as an ultra-rare taxon within the Bithyniidae family.* -
  • The study emphasizes the urgent need for conservation efforts that recognize and preserve the originality of invertebrate species, particularly in unique and extreme environments like river rapids.*
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Background: Ancient Lake Ohrid, located on the Albania-Macedonia border, is the most biodiverse freshwater lake in Europe. However, the processes that gave rise to its extraordinary endemic biodiversity, particularly in the species-rich gastropods, are still poorly understood. A suitable model taxon to study speciation processes in Lake Ohrid is the pulmonate snail genus Acroloxus, which comprises two morphologically distinct and ecologically (vertically) separated endemic species.

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Lake Baikal is the deepest, oldest and most speciose ancient lake in the world. The lake is characterized by high levels of molluscan species richness and endemicity, including the limpet family Acroloxidae with 25 endemic species. Members of this group generally inhabit the littoral zone, but have been recently found in the abyssal zone at hydrothermal vents and oil-seeps.

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Background: The Malili Lakes system in central Sulawesi (Indonesia) is a hotspot of freshwater biodiversity in the Wallacea, characterized by endemic species flocks like the sailfin silversides (Teleostei: Atherinomorpha: Telmatherinidae) radiation. Phylogenetic reconstructions of these freshwater fishes have previously revealed two Lake Matano Telmatherina lineages (sharpfins and roundfins) forming an ancient monophyletic group, which is however masked by introgressive hybridization of sharpfins with riverine populations. The present study uses mitochondrial data, newly included taxa, and different external calibration points, to estimate the age of speciation and hybridization processes, and to test for phylogeographic relationships between Kalyptatherina from ancient islands off New Guinea, Marosatherina from SW Sulawesi, and the Malili Lakes flock.

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Sulawesi, the largest island in the Indonesian biodiversity hotspot region Wallacea, hosts a diverse endemic fauna whose origin has been debated for more than 150 years. We use a comparative approach based on dated phylogenies and geological constraints to test the role of vicariance versus dispersal in the origin of Sulawesi taxa. Most divergence time estimates for the split of Sulawesi lineages from their sister groups postdate relevant tectonic vicariant events, suggesting that the island was predominantly colonized by dispersal.

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Angel sharks of the genus Squatina represent a group comprising 22 extant benthic species inhabiting continental shelves and upper slopes. In the present study, a comprehensive phylogenetic reconstruction of 17 Squatina species based on two mitochondrial markers (COI and 16S rRNA) is provided. The phylogenetic reconstructions are used to test biogeographic patterns.

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