Mind the gap! First records of the harvestman Leiobunum religiosum Simon, 1879 from Belgium (Opiliones: Sclerosomatidae)

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  Mind the gap! First records of the harvestman Leiobunum religiosum Simon, 1879 from Belgium (Opiliones: Sclerosomatidae) Abstract  The harvestman Leiobunum religiosum Simon, 1879 is reported for the first time in Belgium. This large and long-legged species is easy to identify by its contrasting dorsal colour pattern and conspicuous black bands on the leg coxae. Originally an endemic species of the southwestern Alps, it has also been recorded in recent decades from Germany, the Grand Duchy of Luxembourg and the Netherlands. The first confirmed Belgian records date from 2025 in Tellin (Wallonia, province of Luxembourg). It later turned out that a subadult female had already been photographed at the same location in 2017, but only identified later. The species was found on vertical rock surfaces in an old quarry. Based on this finding, an extra search was performed on citizen science platforms, adding eight additional localities for the species in the southeast of the country. ...

Molecular Phylogenetic Relationships Based on Mitogenomes of Spider: Insights Into Evolution and Adaptation to Extreme Environments

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Molecular Phylogenetic Relationships Based on Mitogenomes of Spider: Insights Into Evolution and Adaptation to Extreme Environments

ABSTRACT

In this study, we performed a comparative analysis based on a total of 255 spider mitogenomes and four outgroups, of which the mitogenomes of 39 species were assembled de novo, to explore the phylogenetic relationships and the adaptive evolution of mitogenomes. Results showed that Argyroneta aquatica had the longest mitochondrial length and the most pronounced codon preference to be UUA, followed by CCU. Codon usage frequencies were similar between families and codon usage in the mitogenome of spiders was mainly influenced by natural selection pressures rather than G/C mutation bias. Our phylogenetic topology clearly explained the evolutionary relationships among the spiders, and divergence time estimates indicated that the spiders originated in the early Devonian, and that the two clades of Mesothelae and Opisthothelae separated in the late Carboniferous. Ancestral range and trait reconstruction results supported the ancestral origin of spiders to the Devonian Nearctic realm, with the trapdoor being the original trait. Selection analysis detected positive selection signals in the ATP8 gene in Desis jiaxiangi. The ND5 gene is a convergent evolutionary gene between D. jiaxiangi and A. aquatica. Positive selection signals in the ATP8 gene and convergent selection sites in the ND5 gene may facilitate metabolic adaptation to the aquatic environment in two aquatic spiders. In conclusion, our analysis contributes to a better understanding of the taxonomic status, species diversity, mitochondrial characteristics, and environmental adaptations of these spiders.

Zhang, R., Xiang, N., Gao, X., Zhang, G., Lu, T., & Yuan, T. (2025). Molecular Phylogenetic Relationships Based on Mitogenomes of Spider: Insights Into Evolution and Adaptation to Extreme Environments. Ecology and Evolution, 15(1), e70774. https://doi.org/10.1002/ece3.70774