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

Abstract

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.

An update on the knowledge about scutacarid mites as phoronts and inquilines

“…Until now, only two species of Scutacarus had been reported in association with (nemesiid) spiders, and both had been encountered in South America (Baumann 2018). There has now been an interesting new finding of a scutacarid species phoretic on spiders: a member of Imparipes, most probably a new species, attached between coxae III and IV of the Australian cave-inhabiting anamid spider Troglodiplura beirutpakbarai (Marsh et al 2023). (Baumann and Ferragut 2019).…”

“…Imparipes sp.; Australia; p;Marsh et al (2023) Bombus terrestris Imparipes (I.) rafalskii Dastych, 1978; Ukraine; p;Sobhi et al (2017a), citing an article in Russian byZaloznaya & Khaustov (2007) Scutacarus sp.; USA; p; Uppstrom (2010) Tapinoma tauridis* Imparipes (I.)…”