A Case for Below-Ground Dispersal? Insights into the Biology, Ecology and Conservation of Blind Cave Spiders in the Genus Troglodiplura (Mygalomorphae: Anamidae).

Previously described from only fragments of exoskeleton and juvenile specimens, the cave spider genus Troglodiplura (Araneae: Anamidae), endemic to the Nullarbor Plain, is the only troglomorphic member of the infraorder Mygalomorphae recorded from Australia. We investigated the distribution of Troglodiplura in South Australia, collecting and observing the first (intact) mature specimens, widening the number of caves it has been recorded in, and documenting threats to conservation. Phylogenetic analyses support the placement of Troglodiplura as an independent lineage within the subfamily Anaminae (the 'Troglodiplura group') and provide unequivocal evidence that populations from apparently isolated cave systems are conspecifics of T. beirutpakbarai Harvey & Rix, 2020, with extremely low or negligible inter-population mitochondrial divergences. This is intriguing evidence for recent or contemporary subterranean dispersal of these large, troglomorphic spiders. Observations of adults and juvenile spiders taken in the natural cave environment, and supported by observations in captivity, revealed the use of crevices within caves as shelters, but no evidence of silk use for burrow construction, contrasting with the typical burrowing behaviours seen in other Anamidae. We identify a range of threats posed to the species and to the fragile cave ecosystem, and provide recommendations for further research to better define the distribution of vulnerable taxa within caves and identify actions needed to protect them.

A taxonomic revision of the tube-web spiders of the genus Ariadna (Araneae: Segestriidae) in Tasmania.

The genus Ariadna Audouin, 1826 is revised for Tasmania to include 13 species, ten of which are described as new: Ariadna abbreviata sp. nov., A. alta sp. nov., A. amabilia sp. nov., A. crypticola sp. nov., A. ferrogrisea sp. nov., A. fragilis sp. nov., A. gonzo sp. nov., A. muscosa Hickman, 1929, A. segmentata Simon, 1893, A. subnubilum sp. nov., A. thylacinus sp. nov. and A. tigrina sp. nov.. The species described in this manuscript exhibit high levels of sympatry.

A ghost in the salt: A new species of halotolerant tube-web spider in the genus emAriadna/em (Araneae: Segestriidae).

A new species of halotolerant Ariadna Audouin, 1826 is described from Western Australia, based on morphological features of both the male and female, and elevating the total number of described species of Ariadna in Australia to 14. This is the first record of the tube-web spider family Segestriidae Simon, 1893 inhabiting salt lakes, where they construct burrows in to the lake surface. The species is likely to be of conservation importance, due to its specialised habitat requirements and the many threats posed to the salt lake ecosystem. We provide recommendation for Ariadna phantasma sp. nov. to be considered for inclusion in the IUCN Red List.