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The tanaid Pagurapseudes dentatus was described from a male collected from the intertidal zone at False Bay, South Africa. The description was poorly illustrated, incomplete, did not describe the female or juvenile stages, and gave no information on its habitat. The species was rediscovered and found to be locally abundant at locations in South Africa, where it inhabits vacant gastropod shells. We redescribe P. dentatus by fully illustrating and describing its morphological characters, including the copulatory female and manca II stages. Pagurapseudes dentatus differs from similar species by a long seta on the basis of the characteristically elongated pereopod-1, as well as its singular distal pectinate setae on the propodus and adjacent to the dactylus of pereopod 6. Nano-CT scanning was used to illustrate and document the unusual mode of occupation of empty gastropod shells by the species. It was found (N = 139) occupying shells of 19 gastropod species from 10 different genera, occurring most abundantly in shells of Tricolia Risso, 1826, Burnupena Iredale, 1918, Assiminea Fleming, 1828, and Gibbula Risso, 1826. It forms dense populations under intertidal boulders, where it co-occurs with, and may compete for empty shells, with at least two common species of hermit crabs. [ABSTRACT FROM AUTHOR]

The herbivorous amphipod Sunamphitoe roberta n. sp. is described from the canopy of kelp beds in False Bay, South Africa. The new species has unusual habits, small family groups burrowing directly into the margins of the swollen primary fronds of the kelp Ecklonia maxima (Osbeck) Papenfuss, 1940. Morphologically, the new species is best distinguished from other species of Sunamphitoe by strong rows of dorsal spines on the outer rami of uropods 1 and 2. These spine rows appear to be employed as 'drill-bits' to excavate kelp tissue and create the burrows. Damage to hosts does not appear to be fatal, but requires further investigation. [ABSTRACT FROM AUTHOR]

Background: Along with the conventional deposition of physical types at natural history museums, the deposition of 3-dimensional (3D) image data has been proposed for rare and valuable museum specimens, such as irreplaceable type material. Findings: Micro computed tomography (µCT) scan data of 5 hermit crab species from South Africa, including rare specimens and type material, depicted main identification characteristics of calcified body parts. However, low-image contrasts, especially in larger (>50 mm total length) specimens, did not allow sufficient 3D reconstructions of weakly calcified and fine characteristics, such as soft tissue of the pleon, mouthparts, gills, and setation. Reconstructions of soft tissue were sometimes possible, depending on individual sample and scanning characteristics. The raw data of seven scans are publicly available for download from the GigaDB repository. Conclusions: Calcified body parts visualized from µCT data can aid taxonomic validation and provide additional, virtual deposition of rare specimens. The use of a nondestructive, nonstaining µCT approach for taxonomy, reconstructions of soft tissue structures, microscopic spines, and setae depend on species characteristics. Constrained to these limitations, the presented dataset can be used for future morphological studies. However, our virtual specimens will be most valuable to taxonomists who can download a digital avatar for 3D examination. Simultaneously, in the event of physical damage to or loss of the original physical specimen, this dataset serves as a vital insurance policy. [ABSTRACT FROM AUTHOR]

Surveys of species diversity in sublittoral waters along the coasts of the Cape Peninsula on the Atlantic coast of South Africa yielded three species of Mysidopsis G.O. Sars, 1864. A new species, M. abbreviata   n. sp. is described, a supplementary description is given for M. similis (Zimmer, 1912), and the female of M. zsilaveczi   Wittmann & Griffiths, 2014 is described for the first time. The new species is characterized, among other characters, by a transversely shortened rostrum. Field observations of M. zsilaveczi and M. abbreviata   n. sp. showed the greatest intraspecific diversity of colour patterns ever documented for mysids. Stomach contents, together with differences in the armature of perioral mouthparts and in the foregut, suggest that all three species are specialized predators, mainly of crustaceans. An updated key to the species of Mysidopsis in southern Africa is given. [ABSTRACT FROM AUTHOR]

Background: Brooding brittle stars have a special mode of reproduction whereby they retain their eggs and juveniles inside respiratory body sacs called bursae. In the past, studying this phenomenon required disturbance of the sample by dissecting the adult. This caused irreversible damage and made the sample unsuitable for future studies. Micro X-ray computed tomography (µCT) is a promising technique, not only to visualise juveniles inside the bursae, but also to keep the sample intact and make the dataset of the scan available for future reference. Findings: Seven µCT scans of five freshly fixed (70 % ethanol) individuals, representing three differently sized brittle star species, provided adequate image quality to determine the numbers, sizes and postures of internally brooded young, as well as anatomy and morphology of adults. No staining agents were necessary to achieve high-resolution, high-contrast images, which permitted visualisations of both calcified and soft tissue. The raw data (projection and reconstruction images) are publicly available for download from GigaDB. Conclusions: Brittle stars of all sizes are suitable candidates for µCT imaging. This explicitly adds a new technique to the suite of tools available for studying the development of internally brooded young. The purpose of applying the technique was to visualise juveniles inside the adult, but because of the universally good quality of the dataset, the images can also be used for anatomical or comparative morphology-related studies of adult structures. [ABSTRACT FROM AUTHOR]