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Trabajo presentado en el 5th International Palaeontological Congress, celebrado en París (Francia) del 9 al 13 de julio de 2018, The Fezouata Shale has yielded remarkably diverse assemblages of non-biomineralizing and biomineralizing organisms of Early Ordovician age. Overall, some 160 genera have been documented, about a quarter of which are essentially soft-bodied. Exceptional preservation in the Fezouata Shale occurs in two main separated intervals, of late Tremadocian and mid-Floian age respectively. These intervals are best regarded as distinct Konservat-lagerstätten, since they contain different faunas and are separated in time by c. 9 Ma. Both assemblages are dominated by arthropods, including a diverse trilobite fauna (c. 25 genera). Here we report the discovery of fossilized appendages and guts in 31 trilobite specimens from the lower Fezouata Konservat-lagerstätte belonging to the genera Anacheirurus, Bavarilla, and Prionocheilus (Order Phacopida). The preservation of appendages is generally poor, especially for their proximal parts covered by the dorsal exoskeleton. However, when appendages project from below the dorsal carapace, they exhibit delicate structures, such as annuli boundaries and lateral spines of antennae, or podomere boundaries, clustered endites and terminal claws of endopods. Lamellate exopods are rarely preserved, and when they are, their morphologies are largely obscured by the dorsal carapace. Appendages are typically preserved as thin, yellowish films of iron oxides, interpreted as oxidized pyrite. Among preserved gut structures, Anacheirurus displays a parallel-sided, sediment-filled digestive tract, running under the entire trunk axis while the tract of Bavarilla (wide and sediment-filled) is associated with 10 pairs of digestive glands, which are atypically preserved as a sediment infill. The new examples of fossilized ‘soft’-parts of trilobites from the lower Fezouata Lagerstätte complement previous observations in Megistaspis and Symphysurus, two taxa also belonging to the pilekiid-bavarillid biofacies typical of lower shoreface settings. Despite notable differences in size and affinities, the preservational styles are essentially the same in all specimens, suggesting that only a limited number of taphonomic pathways is responsible for the preservation of trilobite labile parts in these horizons. In addition to the work on the preserved soft parts, the morphological variability of preserved hard parts is currently also under study; in time, this will result in detailed systematic (re)descriptions of the taxa at hand.

The Arouca Geopark, located in the Aveiro district (northern Portugal), originated in 2005 and was formally established in late 2007, under the auspices of Arouca's Municipal Chamber. This ongoing project will soon be submitted to the European and Global Geoparks Networks, making it the second Portuguese geopark inside these networks. During the last three years, an international multidisciplinary team has been working on the rich geodiversity of the area, promoting the inventory and characterization of 36 geological sites, together with the identification of biological and cultural heritage (archaeology, history, ethnography, gastronomy) which are necessary to fulfil the geopark requirements. The link with educational and tourist activities is also progressing, aiming the sustainable development of the region. Among the 36 geological sites subject to preliminary studies and already accessible, two of them are of special international relevance: the Canelas Slate Quarry and its on-site Museum, and the Castanheira Nodular Granite, with a place popularly known as pedras parideiras (= "the stones that give birth", or rather "rocks delivering stones"). The first is an outstanding fossil locality of Darriwilian (Middle Ordovician) age, where giant trilobites (up to 70 cm in size) and trilobite clusters (from several to thousands of specimens) occur in large slabs of shale, recovered during roofing slate quarrying. The Valerio & Figueiredo private company encourages scientific access to its quarry and has built an on-site museum to preserve and disseminate knowledge about trilobites and the Ordovician world. The Geological Interpretation Centre of Canelas, located near the quarry and open since 2006, is one of the main tourist attractions of the Arouca Geopark, having received more than 10,000 visitors in 2007. The Castanheira Granite is a small and very peculiar granite outcrop that contains a remarkable abundance of discoidal biotite nodules ranging from 1−12 cm in diameter, now protected by the Arouca municipality and visited by 15,000 persons during the last year. A popular legend attributes magical properties to these nodules in terms of female fertility, since these dark mineral lumps pop out spontaneously from a creamy-coloured matrix due to differential dilatation during the hot summers. A new interpretation centre will be established in 2008, using an old house close to the outcrop: the "House of Rocks Delivering Stones". The present work is being performed under the project "Identification, Characterization and Conservation of Geological Heritage: a Geoconservation strategy for Portugal" sponsored by the Portuguese Foundation of Science and Technology (PTDC/CTEGEX/64966/2006, years 2007-2009), and is also part of the PATRIORSI project of the Spanish Ministry of Education and Science (CGL2006- 07628/BTE, years 2006-2009).