Filistatinella spiders are found in semiarid areas of North America, and represent an ancient branch of the spider tree of life. After investigating specimens deposited in scientific collections, seven new species were discovered, and their morphology suggests Filistatinella are relatives of Pholcoides from Asia. This study suggests that many Filistatidae species remain to be discovered, and adds yet another piece to the puzzle of early spider evolution.

Neotropical insects are so poorly known that we keep discovering new taxa there, often of a puzzling nature. With the aid of morphology-based phylogenetic analysis, we describe such a rove beetle, a new genus and species placed in the south temperate subtribe Amblyopinina. This is a step towards elucidating Neotropical biodiversity and appreciation of the biogeographic complexity of its core, the tropical Andes.

We describe a novel genus and species of soft coral from North Carolina. This species was not previously reported in the South Atlantic Bight, suggesting it may not be native to the region. The discovery of this species underscores the value of taxonomic work and highlights the need to investigate and document understudied taxa, including soft corals.

All the species belonging to the hydrozoan family Sphaerocorynidae live in association with sponges and often show a confusing taxonomic history. According to both morphological and molecular analyses, we herein describe the new genus and species Astrocoryne cabela from the Red Sea and Maldives. The present study suggests that a comprehensive revision of the family is needed to clarify the diversity and evolution of this taxon.

We reassess the taxonomic status of several Calisto Hübner taxa included in the archebates and hysius species groups. By using COI barcodes and morphological evidence, we recognise Calisto clydoniata Schwartz & Gali and C. chrysaoros Bates as valid species and propose C. clenchi, syn. nov., C. galii galli, syn. nov. and C. galii choneupsilon, syn. nov. as synonyms of C. chrysaoros. Further work must be focused on other species group members to reassess their affinity.

The distinctive ant genus Leptomyrmex Mayr, 1862 had been thought to be endemic to Australasia for over 150 years, but enigmatic Neotropical fossils have challenged this view for decades. Our results highlight the importance of securing sufficient taxon sampling for extant lineages when incorporating fossils and underscore the utility of diverse character sources in accurate placement of fossil terminals. Specifically, we find that fossil placement in this group is influenced by the inclusion of male-based characters and the newly discovered Neotropical ‘Lazarus taxon’.

Velvet worms are a primitive invertebrate group, restricted to forested environments and characterised by limited dispersal. In the present study, the population genetic structure of two velvet worm species was examined. Results demonstrated marked species diversity and genetic structure among forest patches, indicating that forest patches need higher conservation prioritisation.

The taxonomic status and identity of Monomia argentata was confused for long time; previously published studies indicated a presence of its species complex, without resolving the original form. The aim of this study was to examine the type specimen of M. argentata by traditional and modern diagnostic methods, and to clarify its taxonomic position. The type specimen was examined by X-ray and CT-technology, compared with fresh material, and redescribed.