Syllis Savigny in Lamarck, 1818, the type genus of Syllidae, is the largest and most diverse within the family. This genus presents many taxonomic, biogeographic, and phylogenetic problems due mainly to the lack of molecular data and morphological synapomorphies for many of the species, but also due to poor or inadequate descriptions. In order to improve our understanding of the genus, we have undertaken a morphological revision of Australian species, based on type material and material collected over years by the Australian Museum. This is the fourth paper dealing with this genus. Nine species are herein described, of which five are new records for Australia: Syllis ergeni Çinar, 2005; S. patersoni Soto, San Martín & Lucas, 2020; S. valida Grube, 1857; S. violacea Grube, 1870; and S. ypsiloides Aguado, San Martín & ten Hove, 2008. Three species already known from Australia are redescribed: S. heronislandensis (Hartmann-Schröder, 1991) n. comb.; S. parturiens Haswell, 1920; and S. cf. schmardiana Haswell, 1886. Syllis gantheaumensis (Hartmann-Schröder, 1979) n. comb. is raised to species level, since it was originally described as a subspecies of Typosyllis filidentata Hartmann-Schröder, 1962. We include an addendum with a list of species already treated in the previous papers on this genus, as well as some new synonymies after revision of types: Typosyllis (Typosyllis) gerhardi Hartmann-Schröder, 1980 and T. (T.) guildertonensis Hartmann-Schröder, 1979, as synonymous of Syllis busseltonensis (Hartmann-Schröder, 1982); T. (T.) raygeorgei Hartmann-Schröder, 1979 as synonymous of S. hyalina Grube, 1863; T. (T.) rockinghamensis Hartmann-Schröder, 1983 and T. (T.) pseudopapillata Hartmann-Schröder, 1991 as synonymous of S. pharobroomensis (Hartmann-Schröder, 1979). We also include a discussion of the genus and a key to Australian species.

Syllis Savigny in Lamarck, 1818, the type genus of Syllidae, is the largest and most diverse within the family. This genus presents many taxonomic, biogeographic, and phylogenetic problems due mainly to the lack of molecular data and morphological synapomorphies for many of the species, but also due to poor or inadequate descriptions. In order to improve the knowledge of the genus, we have undertaken a morphological revision of Australian species, based on type material and material collected over years by the Australian Museum. This is the third paper dealing with this family. Eighteen species are herein described, of which five are new and twelve are redescriptions of already known species, with four new combinations: Syllis imajimai, n. sp.; S. narranuk, n. sp.; S. noolinga, n. sp.; S. similisunzima, n. sp.; S. thylacine, n. sp.; S. busseltonensis (Hartmann-Schröder, 1982) n. comb.; S. patriciae (Hartmann-Schröder, 1981) n. comb.; S. pharobroomensis (Hartmann-Schröder, 1979) n. comb., S. pharynxcircunfusata (Hartmann-Schröder, 1979) n. comb, S. armillaris (O. F. Müller, 1771); S. augeneri Haswell, 1920; S. benelihauae (Campoy & Alquézar, 1982); S. hyalina Grube, 1863; S. cf. nigrescens Grube, 1878; S. profunda Cognetti, 1955; S. truncata Haswell, 1920; and S. variegata Grube, 1860.

Based on collections of interstitial Syllidae (Annelida) from several areas of the Indo-Pacific Ocean (Madagascar, Andaman Islands, South China, Hong-Kong, the Philippines, and New Zealand), we report a total of 49 species belonging to 19 genera. Most of these species are already known in the Indo-Pacific area, but these reports extend their distributional ranges. Nine species are described as new: Parexogone javieri (from New Zealand), Parexogone viejoi (from the Philippines), Prosphaerosyllis fittoni, Sphaerosyllis dieteri, Syllis kai, Perkinsyllis tsilo (from Madagascar), and Megasyllis chiki, Syllis dominguezi, and Syllis escribanoi (from China). Two species, previously described as Streptosyllis Webster & Benedict, 1884 are transferred to the genus Streptospinigera Kudenov, 1983: S. baolingi (Ding & Westheide, 1994), new combination, and S. hainanensis (Ding & Westheide, 1994), new combination, both from China. One species is transferred to Syllis [Typosyllis botosaneanui (Hartmann-Schroder, 1973)], new combination.

Three new species of the genus Syllis Savigny in Lamarck, 1818, from the Chilean Patagonia are described, figured and discussed. The specimens were collected in boulders, sediment bottoms, Macrocystis pyrifera holdfasts, and inside tubes of Chaetopterus cf. variopedatus. Syllis patagonica n. sp., is characterized by its color pattern, short, fusiform dorsal cirri, plenty of hyaline inclusions, acuminate posterior acicula, and compound chaetae with slightly bidentate falcigers. Syllis terraeignium n. sp., has similar compound chaetae, but dorsal cirri are longer than those of the above mentioned species, a long proventricle, and the posterior acicula are straight, pointed. Finally, Syllis patersoni n. sp., has a slender, elongated body, with moderately long dorsal cirri, plenty of hyaline inclusions, acuminate posterior acicula, and compound chaetae composed by falcigers and short spiniger-like.

Resumen La realidad extendida combina entornos reales y virtuales mediante interacciones generadas por ordenador, permitiendo extender y ampliar las experiencias sensoriales del usuario. Actualmente, las experiencias de realidad extendida más conocidas son la realidad aumentada (RA) y la realidad virtual (RV) que se están incorporando de manera incremental en áreas que abarcan desde el marketing, a la sanidad. A pesar de que la aplicación de estas tecnologías a la educación es aún reciente, muestran un enorme potencial ya que fomentan de manera significativa la motivación y aprendizaje de los estudiantes, se adaptan a distintos estilos de aprendizaje, reducen en cierta medida desigualdades sociales, y facilitan la inclusividad y atención a la diversidad en el aula. En este trabajo, presentamos un proyecto que incorpora elementos de RA y RV a la docencia universitaria, con el objetivo de proporcionar una experiencia de aprendizaje que favorezca la inmersión en el tema/asignatura y que complemente las prácticas de campo de asignaturas relacionadas con la biología marina. Proporcionamos información detallada sobre el proceso diseño y creación del material para promover y facilitar el uso de estas herramientas a cualquier docente interesado. Abstract Extended reality technologies combine real and virtual environments through computer generated interactions, allowing to extend and amplify the sensory experiences of the user. Currently, the most widely known extended reality experiences are augmented reality (AR) and virtual reality (VR) which are being increasingly incorporated in a wide variety of areas that range from marketing to health care. Despite the relatively recent application of these technologies in education they have already shown an enormous potential, as they significantly improve student motivation and learning, adapt to different learning styles, reduce social inequalities to some extent, and facilitate inclusiveness and diversity practices in the classroom. In this work, we present a project that incorporates AR and VR to university teaching, with the aim of offering an immersive learning experience that complements field work practices in courses related to marine biology and zoology. Using 360º images and the open source software Roundme, we have developed a virtual itinerary through a rocky shore in O Grove (Galicia, Spain), in which students can observe and study the biodiversity associated to the distinct intertidal zones. We have also created an underwater VR 360º video that allows students to experience a virtual SCUBA dive in the Marine Reserve of Parque Natural de Cabo de Gata-Níjar (Almería, Spain). During this virtual dive, students can observe and identify the rich biodiversity associated to Posidonia oceanica meadows as well as other characteristic species and communities of this marine protected area, even if they can’t swim or if they are hundreds of kilometers away from the coast. Lastly, we have also designed an AR app that allows the visualization of representative marine invertebrate 3D models and internal anatomy videos through a smartphone. The 3D models were created with the app Qlone and integrated with QR codes using the software Creator to develop the app VitrinasXR, which can be accessed with the open source app Scope. AR and VR are among the tools with the most potential to revolutionize education, significantly promoting motivation and learning in the classroom. The technological advances and popularity of these tools has made them easy to use for both the teachers and the students, allowing their effective use in education. Specifically, the application of these technologies to develop virtual itineraries and field trips has added benefits, allowing access to students from all socio-economic backgrounds, providing flexibility to adapt to different learning styles, and promoting inclusivity and diversity practices in the classroom. Here, we provide detailed information regarding the design and creation of our marine biology AR and VR teaching materials, in order to facilitate and encourage their use in higher education by any interested party.

During a study on the Syllidae (Annelida) inhabiting artificial panels in the Red Sea, five species have appeared as the first colonizers in the first sampling carried out after three months: Syllis crassicirrata (Treadwell, 1925); Syllis gerlachi (Hartmann-Schroder, 1960); Syllis picta (Kinberg, 1866); Syllis schulzi (Hartmann-Schroder, 1960); and Syllis warrnamboolensis (Hartmann-Schroder, 1987). Syllis gerlachi and S. schulzi, already known from the Red Sea, are re-described on the basis of the collected material and type-specimens. The other three species, S. picta, S. warrnamboolensis and S. crassicirrata, recently re-described from Australia, are new for the Red Sea. The most abundant species, S. crassicirrata, shows an interesting variation of colour pattern, which may indicate the presence of a complex of pseudo-cryptic species. A molecular phylogeny was also performed in order to investigate the evolutionary relationships of the Red-Sea species within the genus Syllis.

A collection of more than 1500 specimens of Syllidae (Annelida, Polychaeta) from sub-Arctic and Boreal regions along the coast of Norway has been studied. We report 32 species, two of them new to science, belonging to the generaSphaerosyllisClaparède, 1863 andSyllisSavigny in Lamarck, 1818, and 16 new to Norway.Sphaerosyllis tarqueisp. nov. is characterized by having long blades on its compound chaetae and the presence of glands inside the dorsal cirri.Syllis kassp. nov. was reported, figured and described by Uschakov (1955) asSyllis oerstedi(Malmgren, 1867); however, revision of the types ofChaetosyllis oerstedireveals that they are sexual stolons ofSyllis cornutaRathke, 1843; this species is characterized by the shape of the spiniger-like chaetae, which are relatively short, distally blunt, with a thin distal spine, and unidentate falcigers some of which have similar spines. We also include descriptions and figures ofParexogone longicirris(Webster & Benedict, 1887) andSyllides longocirrataØrsted, 1845. Finally we include a key of all reported species in the area.

Based on material collected during the DIVA-Artabria I project (2002 cruise) from deep areas (629-1132m) of the shelf and upper slope off the Artabro gulf (Galicia, NW Spain), two new species of Syllidae (Annelida: Polychaeta) are described. Eurysyllis mercuryi sp. nov. is characterized by having compound chaetae with elongated blades, provided with long spines, and Syllis mercedesae sp. nov. is diagnosed by the possession of a unique combination of straight aciculae, protruding from parapodial lobes in posterior-most chaetigers, and moderately long spiniger-like chaetae in midbody provided with indistinct subdistal tooth, appearing almost unidentate. Eurysyllis mercuryi sp. nov. is the fifth species of the genus described worldwide and the second reported species in European waters after E. tuberculata Ehlers, 1864.

In this paper a description of Acritagasyllis longichaetosus, an enigmatic genus and species of Syllidae (Polychaeta), is given The new genus is characterized by a lack of palps, eyes, and median antenna, having a single pair of tentacular (peristomial) cirri, distinct ventral cirri fused all along their length to parapodial lobes, a slender, coiled pharynx without trepan but with a pharyngeal tooth, compound chaetae with long shafts, distally enlarged and spinose, and long, filiform blades, quite similar to those belonging to members of the family Phyllodocidae These characters are very unusual and unique among syllids Some characters, like the presence of nuchal lappets, bayonet-shaped simple chaetae, and perhaps also the fusion of ventral cirri to parapodial lobes, bear some resemblance to those of species of Autolytinae However, this new polychaete does not fit into this subfamily as it possesses ventral cirri, the chaetae are very different, and it lacks a trepan in the pharynx, nor can it be placed into any other subfamily, being an "incertae sedis" among the genera of Syllidae