Alien spiders in a palm house with the first report of parthenogenetic Triaeris stenaspis (Araneae: Oonopidae) infected by Wolbachia from new supergroup X.

Palm houses in Europe serve as urban biodiversity hot spots for alien spiders. As a result of several years of research in the Poznań Palm House, we documented the occurrence of 14 spider species, 9 of which were alien to Europe: Coleosoma floridanum, Hasarius adansoni, Howaia mogera, Ostearius melanopygius, Parasteatoda tabulata, Parasteatoda tepidariorum, Scytodes fusca, Spermophora kerinci and Triaeris stenaspis. The most abundant species was C. floridanum (39.9%). Three spider species were recorded for the first time in Poland: C. floridanum, S. fusca and S. kerinci. We studied the occurrence of endosymbiotic Wolbachia and Cardinium in parthenogenetic T. stenaspis and recorded for the first time the occurrence of Wolbachia in this spider. The endosymbiont was characterized based on the sequences of six bacterial housekeeping genes: 16S rRNA, coxA, fbpA, ftsZ, gatB and hcpA. Our phylogenetic reconstruction of Wolbachia supergroups revealed that the bacteria recovered from the spider formed distinct lineages in relation to all known supergroups. We assigned it to a novel supergroup X with unique sequences within the 16S rRNA and ftsZ genes. We discussed faunistic results in terms of long-term survival rates and the risk of invasion of alien species of spiders.