How many stars are…in the sea? An accurate knowledge of biodiversity is the only way to preserve it. Diversity in cryptic cushion stars was evidenced through morphological and molecular features, describing two new species for Science. Changing our perception of diversity within Asterina should necessarily derive in designing urgent conservation measures for these species that inhabit restricted and fragile areas.

Clitellate worms are common in all seas, but their diversity in the South Atlantic Ocean is less well-known than in other parts of the world. We investigated the genetic diversity of a sample of South Atlantic clitellates using COI barcoding, confirming that this approach is an efficient method for formulating Primary Species Hypotheses (PSH) of such marine worms. The study is a contribution to the knowledge of the biodiversity of marine clitellates and demonstrates a fast and cost-effective way to include clitellate species diversity in ecological studies of the marine benthos.

Two or more species are considered cryptic species if they are morphologically indistinguishable, being classified as a single nominal species. Herein we study a group of four striped flatworms from the genus Pasipha, which constitute cryptic species, describing three of them as new species. The study represents the first integrative taxonomic approach for species of this genus, enhancing knowledge on its geographic and genetic divergence.

The advent of molecular barcoding and shape analysis with geometric morphometrics could make the tedious task of taxonomic training unnecessary. We demonstrate this on a problematic species-complex of marine crustaceans from East Asia. Almost all of the twenty randomly chosen characters show statistically significant interspecific differences in shape and size. This could open a new avenue for taxonomy.

The regions with rocks of high economic interest in Brazil have great richness of cave-dwelling invertebrates, including groups poorly known as palpigrades. In this study, three new troglobitic species of Eukoenenia from caves located at Iron Quadrangle (Minas Gerais, Brazil) are described. Since this area is severely threatened by mining activities, the description of these species is of utmost importance for the conservation of the caves where they occur.

Spirobranchus are colorful marine worms living in tropical and subtropical reefs, but so far, little is known of the species inhabiting the Red Sea. This researches aim was to clear some of the ambiguities in the identification of the species found in the Gulf of Eilat, and discovered a previously unknown species in the process. This is yet another demonstration of the need for further investigation of invertebrate species worldwide.

The article describes a new flatworm species and genus, which represents the first marine planarian occurring in freshwater within a cave. These flatworms are blind and without body pigmentation, representing an obligate cave-dwelling population that lives in a harsh, semiarid Neotropical environment. The restricted distribution of the new species and recent environmental conditions detected in this area raise major concern for its conservation.

The so-called ‘controversy’ of taxonomy based only on morphology is an issue affecting many groups, including springtails, the most ancient hexapod group. Thanks to the application of integrative taxonomy, combining morphological and molecular data, we have clarified the phylogenetic relationships of the five European species-groups recognised within the genus Lepidocyrtus.

Reconciling traditional morphology-based taxonomy and evolutionary relationships inferred from DNA is an important aim for modern zoologists, but has rarely been done in earthworms. In this work all available information sources were integrated to revise the systematics of the Mediterranean family Hormogastridae, obtaining a new system of genera (with morphological and ecological diagnoses) which reflects their phylogeny. The new perspective on their diversity highlights the importance of species description and conservation for these and other earthworm families.

Limits among species and speciation process are two main areas of interest in evolutionary studies. Here we assessed the possible causes of speciation in a complex of three incipient species of blister beetles. Phenotypic divergence in colour, and not species niches, can be an enhancing factor of cohesion for the species involved.

Although external shell characteristics are commonly used to describe and identify freshwater mussel species, phenotypic plasticity and morphological convergence are common within Pleurobemini. Using phylogenetic and species delineation approaches, we assessed species boundaries among species and found multiple conspecifics and currently unrecognized taxa. Because many species within Pleurobemini are imperiled, the information is important to develop effective conservation strategies.

Australia is home to thousands of undescribed species, the so-called taxonomic impediment, which we address in this work. We set out to document and understand the phylogenetic position of a group of long-headed bugs that have been recently collected. We formally describe five new genera and ten new species, as well as document their host plant associations.