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- Running crabs, walking crinoids, grazing gastropods: behavioral diversity and evolutionary implications in the Cabeço da Ladeira lagerstätte (Middle Jurassic, Portugal)Publication . Carvalho, Carlos Neto de; Pereira, Bruno Claro; Klompmaker, Adiel; Baucon, Andrea; Moita, José António; Pereira, Pedro; Machado, Susana; Belo, João; Carvalho, Jorge M. F.; Mergulhão, LiaIchnology is a powerful tool for understanding the evolutionary paths of animal clades, through the paleobiology of behavior preserved in Lagerstätten such as the Cabeço da Ladeira (Portugal) site. Here, the peritidal carbonates of the Chão das Pias Formation (Middle Jurassic, upper Bajocian) record the development of microbial mats in a tidal flat. Episodically, the flat was expanded during periods of equinoctial spring tides that may have been responsible for the in situ killing of several members of echinoderm clades, and the fine preservation of their endoskeleton, in addition to the behavior of an arthropod-dominated endo- and epifauna. Mat-preserved shallow tiers with a moderate ichnodiversity attributed to the Cruziana ichnofacies include trackways of crabs (Laterigradus lusitanica igen. nov., isp. nov.) and shrimps ( Diplopodichnus isp.); trails of fishes (?Undichna), gastropods (Archaeonassa fossulata), isocrinid crinoids (Krinodromos bentou igen. nov., isp. nov.) and insects (Haplotichnus indianensis); and burrows of shrimps or lobsters (Thalassinoides suevicus) and other arthropods (Asterosoma ludwigae, Gyrochorte comosa), or polychaetes (Rhizocorallium commune ). This is implied already above (igen. nov., etc.) and seems not needed. The crab trackways and gastropod bulldozing trails, extending up to 12.3 m, are among the longest invertebrate cursorial traces ever found in the fossil record. The mortichnial crawling trail of a crinoid is the first evidence of locomotion for this group in the fossil record, and a rare unambiguous example of this ethology. Extensive continuous trackways attributed to amphibious crabs record, with great detail, typical gaits of underwater punting and walking sideways on dry land. The earliest evidences of sidewalking behavior may also be evidence for the development of the crab form during their rise in the Jurassic.
- Geoconservation in the Cabeço da Ladeira Paleontological Site (Serras de Aire e Candeeiros Nature Park, Portugal): exquisite preservation of animals and their behavioral activities in a Middle Jurassic carbonate tidal flatPublication . Machado, Susana; Mergulhão, Lia; Pereira, Bruno Claro; Pereira, Pedro; Carvalho, Jorge M. F.; Anacleto, José António; Carvalho, Carlos Neto de; Belo, João; Paredes, Ricardo; Baucon, AndreaThe Cabeço da Ladeira paleontological site in central Portugal became known as the “Jurassic Beach”. Formerly an active quarry, the site was protected in order to preserve the large exposures of a Middle Jurassic (early? Bajocian) carbonate tidal flat with an outstanding fossil record. This multidisciplinary paleontological work involving experts from several national and international research and geoconservation institutions was carried out under the umbrella of the Institute for Nature Conservation (ICNF), since this geosite is located within the Serras de Aire e Candeeiros nature park. Cabeço da Ladeira has provided exquisitely preserved body fossils, especially echinoderms, together with the exceptional preservation of their, and other, animal’s behaviors. It is also a hotspot to understand the diversity of bivalves in the Middle Jurassic. Due to the large area of the geosite, the international relevance of the findings, and the risk of weathering and destruction of the fossils, a geoconservation plan has been developed by ICNF with the support of local authorities. After several years of being open to visitors without proper control, the Cabeço da Ladeira paleontological site is now conditioned to organized groups of researchers, schools, and tourists. Some body fossils were collected for studies and included in the national collections of the Geological Museum (Lisbon). Moreover, casts have been made to protect holotypes of trace fossils, also providing ways to replicate this fossil record in temporary exhibitions. A long-term experimental study to conserve the limestone bedding plane exposures and their fossil contents was started in order to develop the best geoconservation strategy with an aim to reduce the damage produced by the increasing tourist demand on natural sites. Cabeço da Ladeira and other geosites in protected areas are key to communicating an evolutionary approach to environmental education, and their geoconservation must be a priority to improve their long-term use as (geo)tourism attractions.
- Equinodermes do Cabeço da Ladeira : um caso de preservação do património geológicoPublication . Pereira, Bruno Claro; Machado, Susana; Carvalho, Jorge M. F.; Mergulhão, Lia; Pereira, Pedro; Duarte, Manuel; Anacleto, JoséO presente trabalho pretende descrever o processo de intervenção no geossítio Equinodermes do Cabeço da Ladeira, concelho de Porto de Mós. Este local foi assim classificado por conter fósseis de equinodermes detentores de importância científica significativa, merecendo especial atenção e medidas de preservação. Expõem-se os passos tomados desde a sua identificação ate às ações mais recentes, que envolveram a inventariação dos exemplares fósseis. O futuro do local é também abordado, pretendendo-se que passe pela requalificação do local como espaço de visitação musealizado.