An unusual natural product (dotofide, 1), in which the terpenoid skeleton is interrupted by a guanidine moiety was obtained from the marine slug Doto pinnatifida. The absolute configuration of compound 1 was deduced by ozonolysis and subsequent CD spectroscopy. D. pinnatifida subsists on the hydrozoan Nemertesia antennina (Cnidaria), which however does not contain dotofide, suggesting that the snail is able to perform the biosynthesis of the metabolite by itself. D. pinnatifida is grouped into the chemically hardly investigated taxon Cladobranchia (Opisthobranchia, Gastropoda). All members of this taxon completely lack a shell and are thought to employ toxic secondary metabolites or alternatively cnidocysts sequestered from their cnidarian prey organism as defence strategy.

SUMMARY: Knowledge on taxonomy and ecology of leptostracan crustaceans is still scarce in many parts of the world. Sampling in subtidal sediments in the Ria of Ferrol (NW Spain) between 2006 and 2007 yielded several leptostracan specimens belonging to six species. This is, so far, the largest number of leptostracan species reported from a single area. Some specimens belong to an undescribed species of Nebalia Leach, 1814, which is described herein as N. reboredae n. sp. The new species has a rostrum about 2.2 times as long as wide, the antennular scale is slightly more than twice as long as wide, the fourth article of the antennule has one short thick distal spine, the first article of the endopod of the second maxilla is 1.3 times as long as the second one, the exopod of the second maxilla is longer than the first article of the endopod, the posterior dorsal borders of pleonites 5-7 are provided with distally rounded to truncated denticles, and the uropods are as long as pleonite 7 and the anal somite combined. All the species collected are reported, including the number of specimens, sexual condition and substrate type. A key to all known neritic species of the Iberian Peninsula is provided.Keywords: Crustacea, Leptostraca, Nebalia, Sarsinebalia, subtidal, sediment, Ría de Ferrol, Atlantic.RESUMEN: Leptostráceos (Crustacea: Phyllocarida) de la Ría de Ferrol (Galicia, NO península Ibérica) con la descripción de una nueva especie de Nebalia Leach, 1814. -El conocimiento sobre la taxonomía y ecología del orden Leptostraca en muchas partes del mundo es todavía fragmentario. El examen de muestras infralitorales recolectadas en la Ría de Ferrol (NO península Ibérica) entre 2006 y 2007 ha revelado la presencia de seis especies de leptostráceos. Hasta la fecha, este es el mayor número de especies encontradas en una única área. Varios de los ejemplares encontrados pertenecen a una especie no descrita del género Nebalia Leach, 1814, que es descrita en el presente trabajo como N. reboredae n. sp. La nueva especie se caracteriza por presentar un rostro 2.2 veces más largo que ancho, una escama antenular algo más de dos veces más larga que ancha, el cuarto segmento de la anténula porta una única espina corta gruesa distal, el primer segmento del endopodio de la segunda maxila es 1.4 veces más largo que el segundo segmento, el exopodio de la segunda maxila es más largo que el primer segmento del endopodio, los dentículos del borde posterior dorsal de los pleonitos 5-7 son distalmente de redondeados a truncados, y los urópodos son tan largos como el pleonito 7 y el somita anal combinados. Se indica para todas las especies encontradas tanto el número de ejemplares como estado sexual y tipo de sustrato. Se incluye una clave para todas las especies de leptostráceos neríticos encontrados en la península Ibérica hasta la fecha.

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During RV MS Merian expedition MSM75, an international, multidisciplinary team explored the Reykjanes Ridge from June to August 2018. The first area of study, Steinahóll (150–350 m depth), was chosen based on previous seismic data indicating hydrothermal activity. The sampling strategy included ship- and AUV-mounted multibeam surveys, Remotely Operated Vehicle (ROV), Epibenthic Sledge (EBS), and van Veen grab (vV) deployments. Upon returning to Steinahóll during the final days of MSM75, hydrothermal vent sites were discovered using the ROV Phoca (Kiel, GEOMAR). Here we describe and name three new, distinct hydrothermal vent site vulnerable marine ecosystems (VMEs); Hafgufa, Stökkull, Lyngbakr. The hydrothermal vent sites consisted of multiple anhydrite chimneys with large quantities of bacterial mats visible. The largest of the three sites (Hafgufa) was mapped, and reconstructed in 3D. In total 23,310 individual biological specimens were sampled comprising 41 higher taxa. Unique fauna located in the hydrothermally venting areas included two putative new species of harpacticoid copepod (Tisbe sp. nov. and Amphiascus sp. nov.), as well as the sponge Lycopodina cupressiformis (Carter, 1874). Capitellidae Grube, 1862 and Dorvilleidae Chamberlin, 1919 families dominated hydrothermally influenced samples for polychaetes. Around the hydrothermally influenced sites we observed a notable lack of megafauna, with only a few species being present. While we observed hydrothermal associations, the overall species composition is very similar to that seen at other shallow water vent sites in the north of Iceland, such as the Mohns Ridge vent fields, particularly with peracarid crustaceans. We therefore conclude the community overall reflects the usual “background” fauna of Iceland rather than consisting of “vent endemic” communities as is observed in deeper vent systems, with a few opportunistic species capable of utilizing this specialist environment.

Solenogastres are vermiform marine molluscs characterised by an aculiferous mantle, a longitudinal ventral pedal groove and a terminal or subterminal pallial cavity. Their classification is based in part on the type of mantle sclerites, but identification to even the family level generally requires the study of internal anatomical characters. Taxonomically important internal characters include those related to radular structure, the type of ventrolateral glandular organs of the pharynx and the reproductive system, among others. In order to study their internal anatomical organisation, according to the classical reconstruction method, serial histological sections of specimens are made, from which the 2D internal anatomy of the specimen can be reconstructed manually. However, this is a time-consuming technique that results in destruction of the specimen. Computed microtomography or micro-CT is a non-destructive technique based on the measurement of the attenuation of X-rays as they pass through a specimen. Micro-CT is faster than histology for studying internal anatomy and it is non-destructive, meaning that specimens may be used for e.g., DNA extraction or retained as intact vouchers. In this paper, the utility of micro-CT for studying taxonomically important internal anatomical structures was assessed. Results of the 3D anatomical study of the soft parts of four specimens of three species using micro-CT are presented: Proneomenia sluiteriHubrecht, 1880, Dorymenia menchuescribanaeGarcía-Álvarez et al., 2000 and Anamenia gorgonophilaKowalevsky, 1880. Micro-CT enabled detailed study of most taxonomically important anatomical characters, precise measurements of structures, and observation of the relative position of organs from a variety of angles. However, it was not possible to observe the radula and some details of the ventral foregut organs could not be discerned. Despite these limitations, results of this study highlight micro-CT as a valuable tool to compliment histology in the study of solenogaster anatomy and in non-destructively identifying animals to the family and even genus-level.