Hidden in the woods: A new species of Hexura (Araneae, Mygalomorphae, Antrodiaetidae) from a highly restricted range in Idaho

  Hidden in the woods: A new species of Hexura (Araneae, Mygalomorphae, Antrodiaetidae) from a highly restricted range in Idaho Abstract A new species of Hexura Simon, 1885 is described from a very restricted geographic range in the Rocky Mountains of Idaho, 500 km east of the previously known distribution of the genus in the Coastal Ranges and western Cascade Mountains of Oregon and Washington. This work provides the first taxonomic information for this group in almost 50 years, including a phylogenomic framework for the genus within the mygalomorph superfamily Atypoidea , based on Ultraconserved elements ( UCEs ). Hexura vandal sp. nov . can be distinguished from the other two described species by a combination of morphological, molecular, and geographic characteristics. Lastly, we discuss the need for conservation actions to secure the survival of the species. Calatayud-Mascarell A, Briggs EJ, Hamilton CA (2026) Hidden in the woods: A new species of Hexura (Araneae, Mygalomo...

Integrative systematics of the tarantulas Euathlus Ausserer, 1875 from Argentina: cladistics, molecular phylogeny and new species (Araneae: Theraphosidae)

 



Integrative systematics of the tarantulas Euathlus Ausserer, 1875 from Argentina: cladistics, molecular phylogeny and new species (Araneae: Theraphosidae)

Abstract

The present study contributes to the understanding of the diversity within the tarantula genus Euathlus Ausserer, 1875. Through a combination of cladistic, molecular, and morphological analyses, three new species are described: Euathlus basalticus sp. nov. from Neuquén, Euathlus kupal sp. nov. from Mendoza, and Euathlus susanae sp. nov. from the La Pampa-Mendoza provinces. Additionally, the female of Euathlus tenebrarum Ferretti, 2015 is described for the first time, revealing that the previously attributed female of this species belongs to E. basalticus sp. nov. Phylogenetic trees from both morphological and molecular datasets are presented. Preliminary molecular analyses reveal the identity and support the proposal of the species treated here. Morphological analyses found considerable diversity within Euathlus, particularly in genitalic structures, challenging the general assumption of morphological homogeneity among mygalomorph spiders. Cladistic analyses recovered the genus Phrixotrichus within Euathlus, though this hypothesis could not be tested with molecular data due to the lack of available sequences for Phrixotrichus. These results suggest that future taxonomic revisions may be complemented once molecular data become available. Altogether, our results provide new insights into the systematics and diversity of Euathlus and highlight the importance of integrative approaches for unraveling evolutionary relationships within this group.

Allegue M, Peralta-Seen N, Ferretti N (2025) Integrative systematics of the tarantulas Euathlus Ausserer, 1875 from Argentina: cladistics, molecular phylogeny and new species (Araneae: Theraphosidae). Arthropod Systematics & Phylogeny 83: 713-736. https://doi.org/10.3897/asp.83.e171040