Integrative taxonomy of the genus Nesticus in central Japan, with the description of a new species and redescriptions of N. echigonus and N. gondai (Araneae, Nesticidae)

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  Integrative taxonomy of the genus Nesticus in central Japan, with the description of a new species and redescriptions of N. echigonus and N. gondai (Araneae, Nesticidae) Abstract Species of the genus Nesticus ( Araneae , Nesticidae ) in central Japan are revised based on morphological and molecular analyses of specimens collected from Niigata and Gunma Prefectures. Among them, a putative undescribed species was discovered having clearly distinguishable morphological characters from other known species in the same area. A phylogenetic analysis based on the mitochondrial COI gene was carried out using a maximum-likelihood method to confirm its distinctiveness. The new species, Nesticus yamabushi sp. nov ., is described based on specimens of both sexes. Furthermore, we provide detailed redescriptions of two other closely related species, N. echigonus and N. gondai , to address the lack of information in their original descriptions and facilitate future identifications. This s...

Biogeography of the widespread Aotearoa New Zealand mite harvester genus Rakaia (Arachnida, Opiliones, Cyphophthalmi) based on UCE-derived subgenomic data

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Biogeography of the widespread Aotearoa New Zealand mite harvester genus Rakaia (Arachnida, Opiliones, Cyphophthalmi) based on UCE-derived subgenomic data

Abstract

Aotearoa New Zealand is home to a remarkable number of endemic taxa, some of which have existed on the archipelago since before the breakup of Gondwana. The mite harvesters (suborder Cyphophthalmi), tiny non-spider arachnids that dwell in forest leaf litter and caves, are one such group. The mite harvester family Pettalidae Shear exhibits a classic Gondwanan distribution with notable diversity in Aotearoa, which is home to three pettalid genera. Our research focuses on the evolution of the most widespread and speciose Aotearoa pettalid genus, Rakaia Hirst, 1926. Through phylogenetic analysis, we provide a window into patterns of ancient diversification and infer historical biogeographic trends. We generated subgenomic data through target enrichment of ultraconserved elements (UCEs) using an Arachnida-specific probe set; the 50% and 75% taxon-occupancy matrix retrieved 848 and 585 loci, respectively. In addition to generating the first fully resolved phylogeny of Rakaia, we performed a molecular clock analysis and tested for shifts in diversification rates in order to explore the effect of geological events such as the Oligocene Drowning, the uplift of Kā Tiritiri o te Moana, and forest habitat contraction and fragmentation during the Last Glacial Maximum.

Alafranji, Z. R., Morisawa, R., Aspholm, P. L., Fu, P. A., W. Moyes, N. H., A. Heine, H. L., Hejmadi, S. R., Derkarabetian, S., & Boyer, S. L. (2026). Biogeography of the widespread Aotearoa New Zealand mite harvester genus Rakaia (Arachnida, Opiliones, Cyphophthalmi) based on UCE-derived subgenomic data. Systematic Entomology, 51(1), e70021. https://doi.org/10.1111/syen.70021