We elucidate the evolutionary history of carabid beetle Cnemalobus species restricted to isolated northern Patagonian Steppe volcanoes. This system exhibits high endemism, but diversification and biogeographical patterns remain poorly understood. Our analyses suggest monophyly of the new species and that past climatic conditions could have shaped the allopatry related to high elevation–low latitude. Our findings significantly enrich the evolutionary knowledge of the extra-Andean Patagonian mountain endemic biota, emphasising the crucial role of these systems in speciation. (Photograph by Sergio Roig-Juñent.)

Syllis prolifera is a putative cosmopolitan species with historically synonymised reports worldwide and variability among different populations. We conducted an integrative phylogenetic assessment of this species using morphological, ecological and molecular (16S rRNA and COI) data from five western Mediterranean populations. Our analysis identified five well-supported lineages suggesting that pseudocryptic speciation may be pervasive for this species and the true diversity within Syllidae is understimated. (Image credit: Irene del Olmo.)

We studied the phylogeny, biogeography and larval biology of sister genera Gatzara and Nepsalus (Myrmeleontidae: Dendroleontinae). We discovered new specimens and previously unknown larvae of rare species G. jubilaea Navás, 1915, N. insolitus (Walker, 1860) and N. decorosus (Yang, 1988). Nepsalus maclachlani Badano, Zheng & Liu, sp. nov. from Sri Lanka is described based on historical collections. (Image credit: Yuchen Zheng.)

Freshwater mussel species diagnosis is challenging due to intraspecific variation and limited morphological traits. The taxonomic status of Scabies longata and Scabies chinensis in China has long been debated, primarily owing to the absence of molecular data. Our molecular and species distribution data supported Scabies longata and Scabies chinensis as synonymous with Nodularia douglasiae and Nodularia nuxpersicae respectively. Phylogenetic analyses based on complete mitochondrial genomes elucidated relationships within Nodularia, highlighting the significance of an integrated taxonomic approach. (Image credit: Yu-Ting Dai and Shu-Ming Ma.)

Subfamily Doryctinae constitutes mainly parasitoid and some phytophagous braconid wasps. Molecular studies recovered a non-monophyletic Doryctinae. We characterised several mitogenomes and conducted phylogenetic analyses to assess the monophyly and higher-level classification. We identified rearrangements of mitochondrial transfer RNAs that support a non-monophyletic Doryctinae constituting two separate unrelated clades, also supported by phylogenetic analyses of mitogenome and nuclear data. Utility of the mitogenome rearrangements was highlighted as a potential source of phylogenetic information at different evolutionary timescales. (Image credit: Rubén Castañeda-Osorio.)

The taxonomic status of the freshwater razor clam Novaculina siamensis Morlet, 1889 is determined using molecular and morphological analyses. Phylogenetic analyses placed the species separately from other currently recognised Novaculina species. Additionally, N. siamensis also possesses distinct morphological characteristics including fused, fringed siphons instead of separated, smooth siphons, as found in the type species of Novaculina s.s. Therefore Cenonovaculina gen. nov. is proposed to accommodate ‘N. siamensis’. (Image credit: Kongkit Macharoenboon.)

The shrimps of Palaemonella and related genera (family Palaemonidae) were revised based on multigene phylogenetic analysis. The genus was revealed to be a diverse paraphyletic group. The shrimps of Eupontonia and Vir were therefore synonymised with Palaemonella. The Atlantic Cuapetes americanus was also transferred into Palaemonella, as well as Periclimenes rhizophorae (which had long been a synonym of C. americanus). The number of known representatives of Palaemonella has increased from 27 to 38 species. (Photographs by: left, A. Anker; right, I. Horká.)

The family Deltocyathidae was recently erected to accommodate Deltocyathus species previously ascribed to Caryophylliidae but Deltocyathus magnificus was phylogenetically recovered within the family Turbinoliidae. Mitochondrial and nuclear sequence data, used for phylogenetic reconstructions, were obtained for 10 Deltocyathidae and Turbinoliidae species. Deltocyathus magnificus is moved to Turbinoliidae and ascribed to the new genus Dennantotrochus. A new mitochondrial gene order is described for Deltocyathus species. Macromorphological features indicate skeletal convergence and microstructural analyses demonstrate possibly conserved biomineralisation mechanisms. (Image credit: C. F. Vaga.)

Northern estuarine populations of Gammarus have given southern siblings the cold shoulder. Cryptic species have been discovered across a variety of organisms, from parasites to giraffes, with wide implications from human to ecosystem health. Our study supports the existence of a cryptic complex within the amphipod species Gammarus tigrinus and G. daiberi due to formation of the Labrador Current (c. 3 Ma). Gammarus tigrinus is highly invasive in Europe, highlighting the need to assess the potential for cryptic diversity of invading populations. (Image credit: Andrew G. Cannizzaro.)

Transfer of key species in the tapeworm order Rhinebothriidea to Semiorbiseptum and its assignment to the family Escherbothriidae greatly affects our understanding of how tapeworms evolved. Some species that parasitise skates have been assigned to a variety of rhinebothriidean genera without prior confirmation using phylogenetic analyses, thus obscuring patterns of host associations. We present evidence that skate-hosted rhinebothriidean taxa are restricted to the families Echeneibothriidae and Escherbothriidae. We believe our findings provide a robust foundation for future research into the diversification of tapeworms within the Rhinebothriidea and beyond. (Image credit: Veronica M. Bueno.)

House centipedes are conspicuous yet often ignored myriapods for which little work has been conducted in southern South America. After examining recent and museum collections from Chile and Argentina, a new genus of scutigerid centipede, Edgethreua, is described with two new species from Central Chile and Argentinian Patagonia. A phylogenetic analysis of the new species using five molecular markers shows that the new genus does not cluster with any other described genus of scutigeromorph represented in molecular phylogenies. This new genus is likely sister group to a clade including the genera Lassophora, Ballonema and the subfamily Thereuoneminae, although another analysis suggests a position as sister group to Scutigerinae. (Image credits: picture, A. Porta; tree, G. Giribet.)

The debatable identity and delimitation of spider species of Mastigusa have confused the taxonomic status and distribution. Broad sampling, and morphological and molecular techniques were used to revise the species’ statuses. Three Mastigusa species were recircumscribed and redescribed, and the distributions updated. Based on a reexamination of type material, Mastigusa diversa O. Pichard-Cambridge, 1893 is revalidated. Mastigusa shows strong ecological plasticity, and understanding the species delimitations and distributions will unravel drivers of extreme lifestyles such as myrmecophily and cave-dwelling. (Image credit: F. Castellucci.)