No abstract

The occurrence of amber in Sierra de Cantabria (álava, Basque Country) has been known for more than two decades but biological inclusions have only recently been found. The existence of crustaceans (amphipods and isopods), chelicerates (acari and arachnids), 12 orders of insects, and several bird feathers are reported in this preliminary study. In addition, there are leaf remains, molluscs, and a fair number of inorganic inclusions.Pollen analysis of the clastic series indicates an age between upper Aptian—middle Albian, which allows an assignment of this stratigraphic unit to the Nograro Formation. Chemical analysis indicates that the amber has high maturity, which reflects its Cretaceous age. Chemical composition analysis also indicates an araucariacean origin, which is corroborated by pollen found within the amber deposit.This new fossil site provides information for the reconstruction of paleocommunities of arthropods and sedimentary environments in the extreme south of the Basque-Cantabrian Basin during the Lower Cretaceous, characterized by coniferous forests with an understory of vascular cryptograms. Some of the identified arthropods add to the fossil record for various groups that are poorly known or unknown for this time period. This Lagerstätte constitutes one of the most important deposits of Mesozoic amber in the world.

Ticks are currently among the most prevalent blood-feeding ectoparasites, but their feeding habits and hosts in deep time have long remained speculative. Here, we report direct and indirect evidence in 99 million-year-old Cretaceous amber showing that hard ticks and ticks of the extinct new family Deinocrotonidae fed on blood from feathered dinosaurs, non-avialan or avialan excluding crown-group birds. A †Cornupalpatum burmanicum hard tick is entangled in a pennaceous feather. Two deinocrotonids described as †Deinocroton draculi gen. et sp. nov. have specialised setae from dermestid beetle larvae (hastisetae) attached to their bodies, likely indicating cohabitation in a feathered dinosaur nest. A third conspecific specimen is blood-engorged, its anatomical features suggesting that deinocrotonids fed rapidly to engorgement and had multiple gonotrophic cycles. These findings provide insight into early tick evolution and ecology, and shed light on poorly known arthropod–vertebrate interactions and potential disease transmission during the Mesozoic.

Amber is an organic multicompound derivative from the polymerization of resin of diverse higher plants. Compared with other modes of fossil preservation, amber records the anatomy of and ecological interactions between ancient soft-bodied organisms with exceptional fidelity. However, it is currently suggested that ambers do not accurately record the composition of arthropod forest paleocommunities, due to crucial taphonomic biases. We evaluated the effects of taphonomic processes on arthropod entrapment by resin from the plant , one of the most important resin-producing trees and a producer of tropical Cenozoic ambers and Anthropocene (or subfossil) resins. We statistically compared natural entrapment by tree resin with the ensemble of arthropods trapped by standardized entomological traps around the same tree species. Our results demonstrate that assemblages in resin are more similar to those from sticky traps than from malaise traps, providing an accurate representation of the arthropod fauna living in or near the resiniferous tree, but not of entire arthropod forest communities. Particularly, arthropod groups such as Lepidoptera, Collembola, and some Diptera are underrepresented in resins. However, resin assemblages differed slightly from sticky traps, perhaps because chemical compounds in the resins attract or repel specific insect groups. Ground-dwelling or flying arthropods that use the tree-trunk habitat for feeding or reproduction are also well represented in the resin assemblages, implying that fossil inclusions in amber can reveal fundamental information about biology of the past. These biases have implications for the paleoecological interpretation of the fossil record, principally of Cenozoic amber with angiosperm origin.

The great evolutionary success of angiosperms has traditionally been explained, in part, by the partnership of these plants with insect pollinators. The main approach to understanding the origins of this pervasive relationship has been study of the pollinators of living cycads, gnetaleans, and basal angiosperms. Among the most morphologically specialized living pollinators are diverse, long-proboscid flies. Early such flies include the brachyceran family Zhangsolvidae, previously known only as compression fossils from the Early Cretaceous of China and Brazil. It belongs to the infraorder Stratiomyomorpha, a group that includes the flower-visiting families Xylomyidae and Stratiomyidae. New zhangsolvid specimens in amber from Spain (ca. 105 mega-annum [Ma]) and Myanmar (100 Ma) reveal a detailed proboscis structure adapted to nectivory. Pollen clumped on a specimen from Spain is Exesipollenites, attributed to a Mesozoic gymnosperm, most likely the Bennettitales. Late Mesozoic scorpionflies with a long proboscis have been proposed as specialized pollinators of various extinct gymnosperms, but pollen has never been observed on or in their bodies. The new discovery is a very rare co-occurrence of pollen with its insect vector and provides substantiating evidence that other long-proboscid Mesozoic insects were gymnosperm pollinators. Evidence is thus now gathering that visitors and probable pollinators of early anthophytes, or seed plants, involved some insects with highly specialized morphological adaptations, which has consequences for interpreting the reproductive modes of Mesozoic gymnosperms and the significance of insect pollination in angiosperm success.

Thirteen species of basal Brachycera (11 described as new) are reported, belonging to nine families and three infraorders. They are preserved in amber from the Early Cretaceous (Neocomian) of Lebanon, Albian of northern Spain, upper Albian to lower Cenomanian of northern Myanmar, and Late Cretaceous of New Jersey USA (Turonian) and Alberta, Canada (Campanian). Taxa are as follows, with significance as noted: In Stratiomyomorpha: Stratiomyidae (Cretaceogaster pygmaeus Teskey [2 new specimens in Canadian amber], Lysistrata emerita Grimaldi & Arillo, gen. et sp. n. [stem-group species of the family in Spanish amber]), and Xylomyidae (Cretoxyla azari Grimaldi & Cumming, gen. et sp. n. [in Lebanese amber], and an undescribed species from Spain). In Tabanomorpha: Tabanidae (Cratotabanus newjerseyensis Grimaldi, sp. n., in New Jersey amber). In Muscomorpha: Acroceridae (Schlingeromyia minuta Grimaldi & Hauser, gen. et sp. n. and Burmacyrtus rusmithi Grimaldi & Hauser gen. et sp. n., in Burmese amber, the only definitive species of the family from the Cretaceous); Mythicomyiidae (Microburmyia analvena Grimaldi & Cumming gen. et sp. n. and Microburmyia veanalvena Grimaldi & Cumming, sp. n., stem-group species of the family, both in Burmese amber); Apsilocephalidae or near (therevoid family-group) (Kumaromyia burmitica Grimaldi & Hauser, gen. et sp. n. [in Burmese amber]); Apystomyiidae (Hilarimorphites burmanica Grimaldi & Cumming, sp. n. [in Burmese amber], whose closest relatives are from the Late Jurassic of Kazachstan, the Late Cretaceous of New Jersey, and Recent of California). Lastly, two species belonging to families incertae sedis, both in Burmese amber: Tethepomyiidae (Tethepomyia zigrasi Grimaldi & Arillo sp. n., the aculeate oviscapt of which indicates this family was probably parasitoidal and related to Eremochaetidae); and unplaced to family is Myanmyia asteiformia Grimaldi, gen. et sp. n., a minute fly with highly reduced venation. These new taxa significantly expand the Mesozoic fossil record of rare and phylogenetically significant taxa of lower Brachycera.

ABSTRACT. Fossil Apis species 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, including Apis aquisextusensis sp. 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. MAA (1953) divided Recent Apis into three genera, Megapis Ashmead, 1904, Apis Linnaeus, 1758 and Micrapis Ashmead, 1904, which Michener (1944 had earlier regarded as subgenera of Apis. To these three, Zeuner and Manning (1976) added the fossil subgenus Synapis Cockerell, 1907 from the Upper Oligocene of France and Germany. We follow the subgeneric classification of Michener (1944) rather than the generic classification of Maa (1953) because there is no good reason to consider Synapis as a separate genus. It is not well-characterized and is almost a 'melting-pot' for the bees of the Oligo-Miocene with plesiomorphic characters in their wing venation. The use of the subgenus Synapis is still convenient for naming some Oligo-Miocene bees but is of little significance in a phylogenetic classification. Since Zeuner and Manning's (1976) work on fossil Apis, which omitted a species described by Riha (1973) from Bohemia, some new species have been discovered in China and Japan. In addition, we have recently found numerous specimens of fossil bees in the Oligocene of Provence, southern France and the Miocene of central France and Cerdanya in Lleida, Spain. We have also restudied the holotype of Synapis cuenoti Théobald, 1937. Our friend Mr P. Brisac has discovered well preserved fossil Apis in the Miocene of Ardèche, France and one of us has recovered two bees in the Miocene of Rubielos de Mora, Teruel, Spain. Localities which have yielded fossil Apis are shown on Text-figure 1.We follow an amended venational nomenclature after Michener (1944), Eickwort (1969, Wootton (1979) and Alexander (1991), but not Maa (1953, p. 538). For the names of points of intersections of veins, we follow the nomenclature of Louis (1963Louis ( , 1966Louis ( , 1971) (see Text- fig. 2A and Table 5). The first article of the hind tarsus is here called the basitarsus (sensu Snodgrass 1956) (¼ metatarsus sensu Ruttner 1988).Although phylogenetic studies of Recent Apis have been undertaken by Alexander (1991), Garnery et al. (1991), andWillis et al. (1992), summarized in Engel and Schultz (1997), it is nearly impossible to integrate fossil bees with these because of the lack of preserved characters. For example, following Alexander's (1991) study, we attempted to make a list of characters that could be examined in nearly all fossil material. We discovered only seven, as follows: (1), compound eyes hairy: present/absent; (2), angle (OSX) of forewing: >45Њ/<45Њ; (3), angle (SVY) of forewing: >45Њ/<45Њ; (4), distal abscissa of hindwing vein M: present/ab...

Abstract. The monophyletic family Zhangsolvidae comprises stout-bodied brachyceran flies with a long proboscis and occurring only in the Cretaceous, originally known in shale from the Early Cretaceous Laiyang Formation (Fm.) in China (Zhangsolva Nagatomi & Yang), subsequently from limestones of the Early Cretaceous Crato Fm. of Brazil. Cratomyoides Wilkommen is synonymized with Cratomyia Mazzarolo & Amorim, both from the Crato Fm.; Cratomyiidae is synonymized with Zhangsolvidae.