MicroCT imaging applied to description of a new species of Pagurus Fabricius, 1775 (Crustacea: Decapoda: Anomura: Paguridae), with selection of three-dimensional type data

New records and species of deep-sea squat lobsters (Galatheoidea, Munidopsidae) from the Hawaiian Archipelago: an integrative approach using micro-CT and barcodes

The Hawaiian Archipelago remains extensively under-sampled for many marine invertebrate taxa, including squat lobsters. During the last few years, several deep-sea expeditions carried out in the Pacific Ocean have conducted opportunistic collections of specimens and image data from the vicinity of Hawai'i. Here we describe a new species: Munidopsis hawaii sp. nov. and provide new records for Munidopsidae in the Archipelago and its associations. We illustrate and describe the new species using an integrative approach including micro-CT 3D imaging. Phylogenetic analyses of the species collected from seamounts from Hawai'i indicate that the new species represents a divergent lineage compared to morphologically similar species such as M. dispar and M. papanui. We also study the genetic distances for the species recorded in Hawai'i and other populations of the same species in the adjacent West Pacific. Three species are now known in the Hawaiian region. We also compiled identifications from images captured with ROVs in the area. These observations suggest that munidopsid species are common in the deep sea of Hawaiian waters below 1,000 m.

An earliest Triassic age for Tasmaniolimulus and comments on synchrotron tomography of Gondwanan horseshoe crabs

Constraining the timing of morphological innovations within xiphosurid evolution is central for understanding when and how such a long-lived group exploited vacant ecological niches over the majority of the Phanerozoic. To expand the knowledge on the evolution of select xiphosurid forms, we reconsider the four Australian taxa: Austrolimulus fletcheri, Dubbolimulus peetae, Tasmaniolimulus patersoni, and Victalimulus mcqueeni. In revisiting these taxa, we determine that, contrary to previous suggestion, T. patersoni arose after the Permian and the origin of over-developed genal spine structures within Austrolimulidae is exclusive to the Triassic. To increase the availability of morphological data pertaining to these unique forms, we also examined the holotypes of the four xiphosurids using synchrotron radiation X-ray tomography (SRXT). Such non-destructive, in situ imaging of palaeontological specimens can aid in the identification of novel morphological data by obviating the need for potentially extensive preparation of fossils from the surrounding rock matrix. This is particularly important for rare and/or delicate holotypes. Here, SRXT was used to emphasize A. fletcheri and T. patersoni cardiac lobe morphologies and illustrate aspects of the V. mcqueeni thoracetronic doublure, appendage impressions, and moveable spine notches. Unfortunately, the strongly compacted D. peetae precluded the identification of any internal structures, but appendage impressions were observed. The application of computational fluid dynamics to high-resolution 3D reconstructions are proposed to understand the hydrodynamic properties of divergent genal spine morphologies of austrolimulid xiphosurids.

Extended depth of focus ultraviolet imaging compared with laser scanning confocal microscopy for the study of micro-Arthropoda surface texture, with the description of a new species of Brachypodopsis (Acari: Hydrachnidia)

Visualization and representation are two processes at the core of basic biodiversity studies. Visualization involves the examination, sorting, and evaluation of similarities and differences among specimens by specialists who then assign them to the same or different species. It is a cognitive process. Representing involves transmitting the knowledge obtained in the first step to others, usually specialists of the group under study, generally through written descriptions aided by representative drawings and/or images. In this work, I describe a new species of water mite, Brachypodopsis guillermoi n. sp. (Acari, Hydrachnidia), from the island of Coiba off the Pacific coast of Panama, using both laser scanning confocal microscopy and extended depth of focus microscopy with visible (wavelength: 400-700 nm) and ultraviolet (wavelength: 365 nm) light. A comparison of the surface texture representation obtained from these imaging methods suggests that extended depth of focus ultraviolet microscopy can be a cost-effective alternative to laser scanning confocal microscopy for the description of exoskeletal features of micro-arthropods.

Radionuclide, magnetic resonance and computed tomography imaging in European round back slugs (Arionidae) and leopard slugs (Limacidae)

Other than in animal models of human disease, little functional imaging has been performed in most of the animal world. The aim of this study was to explore the functional anatomy of the European round back slug (Arionidae) and leopard slug (Limacidae) and to establish an imaging protocol for comparative species study. Radionuclide images with single photon emission computed tomography (SPECT) and positron emission tomography (PET) were obtained after injections of standard clinical radiopharmaceuticals ^99mtechnetium dicarboxypropane diphosphonate (bone scintigraphy), ^99mtechnetium mercaptoacetyltriglycine (kidney function), ^99mtechnetium diethylenetriaminepentaacetic acid (kidney function), ^99mtechnetium pertechnetate (mediated by the sodium-iodide symporter), ^99mtechnetium sestamibi (cardiac scintigraphy) or ¹⁸F-fluoro-deoxyglucose (glucose metabolism) in combination with magnetic resonance imaging (MRI) and computed tomography (CT) for uptake anatomic definition. Images were compared with anatomic drawings for the Arionidae species. Additionally, organ uptake data was determined for a description of slug functional anatomy in comparison to human tracer biodistribution patterns identifying the heart, the open circulatory anatomy, calcified shell remnant, renal structure (nephridium), liver (digestive gland) and intestine. The results show the detailed functional anatomy of Arionidae and Limacidae, and describe an in vivo whole-body imaging procedure for invertebrate species.