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All the amber outcrops of the Iberian Peninsula are Lower Cretaceous in age and, in the case of Spain, some of them have provided important arthropod specimens preserved as bioinclusions. These Spanish localities are rich in fossil taxa of phylogenetic relevance and evidence of both paleoecological interactions and paleobehaviors are also abundant. Despite their high heritage interest, the actions conducted to their protection and management have been very unequal. In some cases, only the generic laws of national or autonomous scopes protect this heritage. In this paper, the state of the art of the Iberian Peninsula amber outcrops and a review of the major Cretaceous amber outcrops worldwide for comparison are presented. That comparison shows, in general, that the best protection, both legal and physical, occurs in Spain and that the case of Portugal is very different. In addition, some actions aimed at a more effective protection and management of the amber outcrops in Spain and Portugal are proposed, for example the proposal to consider the San Just outcrop, located in the Aragonese Community, under a protection designation as is the so called Bien de Interés Cultural. [ABSTRACT FROM AUTHOR]

The cortices of pieces of Cretaceous amber around the world commonly are constituted by networks of filamentous structures. Based on their morphological characteristics, such structures have previously been classified in different microorganismal groups. Their correct interpretation, however, is of great importance to establish the conditions of the resin's burial in the forest litter, and can provide important clues regarding the ecology and environmental conditions of Cretaceous resinous forests. Because these networks of filamentous structures present typical fungal morphological features we conducted a study in order to resolve their origin. The cortices of several pieces of Cretaceous amber from Spain were examined using light and scanning electron microscopy, energy dispersive X-ray spectroscopy and confocal laser scanning microscopy. This is the first time that Calcofluor white and Wheat germ agglutinin conjugated with fluorescein isothiocyanate have been employed as fungal markers in amber, and their use enabled us to detect preserved polysaccharides in the filamentous structures using confocal laser scanning microscopy. These results provide the first and oldest record of β-1,3 and β-1,4-linked polysaccharides, and specifically N-acetylglucosamine residues from chitin in a fossil fungus preserved in amber and to demonstrate that the networks of filamentous structures are mycelia composed of profuse hyphae of a resinicolous fungus. This type of mycelium constitutes one of the largest fungal fossil records known. Using taphonomic data it is demonstrated that the cortices originated during the Cretaceous due to fungal growth within non-solidified resin. The fossil diagenetic degradation sequence of the fungal hyphae and the surrounding amber is described. This degradation changed the microscopic appearance of the hyphae; thus, some of the previously indicated taxonomic features of this microorganism may actually be fossil diagenetic artifacts. The paleoecological implications with regard to fungal trophic requirements and forest environmental conditions are discussed. [ABSTRACT FROM AUTHOR]

FossilApisspecies from the Oligocene, Miocene and Plio-Pleistocene of Eurasia are described and their relationships with Recent species are discussed. Several new populations of fossil bees are reported from the Oligocene and Miocene of France and Spain, includingApis aquisextusensissp. nov. The present state of knowledge of fossil bee systematics is poor because of the general lack of preserved characters. Some of the problems, and items requiring further investigation, are identified. [ABSTRACT FROM AUTHOR]