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Hickmania troglodytes is an emblematic cave spider representing a monotypic cribellate spider genus. This is the only Australian lineage of Austrochilidae while the other members of the family are found in southern South America. In addition to being the largest spider in Tasmania, Hickmania is an oddity in Austrochilidae because this is the only lineage in the family bearing posterior book lungs, tarsal spines and an embolar process on male pedipalps. Six-gene Sanger sequences and genome scale data such as ultraconserved elements (UCEs) and transcriptomes have suggested that Hickmania troglodytes is not nested with the family of current classification, Austrochilidae. We studied the phylogenetic placement of Hickmania troglodytes using an increased taxon sample by combining publicly available UCE and UCEs recovered from transcriptomic data in a parsimony and maximum likelihood framework. Based on our phylogenetic results we formally transfer Hickmania troglodytes from Austrochilidae to the family Gradungulidae. The cladistic placement of Hickmania in the family Gradungulidae fits the geographic distribution of both gradungulids (restricted to Australia and New Zealand) and austrochilids (restricted to southern South America) more appropriately.
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Congruence between ultraconserved element‐based matrices and phylotranscriptomic datasets in the scorpion Tree of Life
Abstract Scorpions are ancient and historically renowned for their potent venom. Traditionally, the systematics of this group of arthropods was supported by morphological characters, until recent phylogenomic analyses (using RNAseq data) revealed most of the higher‐level taxa to be non‐monophyletic. While these phylogenomic hypotheses are stable for almost all lineages, some nodes have been hard to resolve due to minimal taxonomic sampling (e.g. family Chactidae). In the same line, it has been shown that some nodes in the Arachnid Tree of Life show disagreement between hypotheses generated using transcritptomes and other genomic sources such as the ultraconserved elements (UCEs). Here, we compared the phylogenetic signal of transcriptomes vs. UCEs by retrieving UCEs from new and previously published scorpion transcriptomes and genomes, and reconstructed phylogenies using both datasets independently. We reexamined the monophyly and phylogenetic placement of Chactidae, sampling an additional chactid species using both datasets. Our results showed that both sets of genome‐scale datasets recovered highly similar topologies, with Chactidae rendered paraphyletic owing to the placement ofNullibrotheas allenii. As a first step toward redressing the systematics of Chactidae, we establish the family Anuroctonidae (new family) to accommodate the genusAnuroctonus.
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- Award ID(s):
- 2016141
- PAR ID:
- 10429001
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Cladistics
- Volume:
- 39
- Issue:
- 6
- ISSN:
- 0748-3007
- Format(s):
- Medium: X Size: p. 533-547
- Size(s):
- p. 533-547
- Sponsoring Org:
- National Science Foundation
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