Enrique Peñalver

Taphonomy of insects in carbonates and amber

Abstract The major taphonomic processes that control insect preservation in carbonate rocks (limestones, travertines and nodules) are biological: insect size and wingspan, degree of decomposition, presence of microbial mats, predation and scavenging; environmental: water surface tension, water temperature, density and salinity, current activity; and diagenetic: authigenic mineralisation, flattening, deformation, carbonisation. The major taphonomic processes that control the preservation of insects in fossil resins (amber and copal) are different, but can be considered under the same headings – biological: presence of resin producers, size and behaviour of insects; environmental: latitude, climate, seasonality, resin viscosity, effects of storms and fires, soil composition; and diagenetic: resin composition, insect dehydration, pressure, carbonisation, thermal maturation, reworking, oxidation. These taphonomic processes are geographically and temporally restricted, and generate biases in the fossil record. Nevertheless, where insects occur they may be abundant and very diverse. Taphonomic processes may impact on phylogenetic and palaeobiogeographic studies, in determining the timing of the origin and extinction of insect groups, and in identifying radiations and major extinctions. Taphonomic studies are an essential prerequisite to the reconstruction of fossil insect assemblages, to interpreting the sedimentary and environmental conditions where insects lived and died, and to the investigation of interactions between insects and other organisms.

A NEW FOSSIL RESIN WITH BIOLOGICAL INCLUSIONS IN LOWER CRETACEOUS DEPOSITS FROM ÁLAVA (NORTHERN SPAIN, BASQUE-CANTABRIAN BASIN)

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.

Thrips pollination of Mesozoic gymnosperms

Within modern gymnosperms, conifers and Ginkgo are exclusively wind pollinated whereas many gnetaleans and cycads are insect pollinated. For cycads, thrips are specialized pollinators. We report such a specialized pollination mode from Early Cretaceous amber of Spain, wherein four female thrips representing a genus and two species in the family Melanthripidae were covered by abundant Cycadopites pollen grains. These females bear unique ring setae interpreted as specialized structures for pollen grain collection, functionally equivalent to the hook-tipped sensilla and plumose setae on the bodies of bees. The most parsimonious explanation for this structure is parental food provisioning for larvae, indicating subsociality. This association provides direct evidence of specialized collection and transportation of pollen grains and likely gymnosperm pollination by 110–105 million years ago, possibly considerably earlier.

Une faune très diversifiée du Pléistocène inférieur de la Sierra de Quibas (province de Murcia, Espagne)

The Quaternary karstic site of Sierra de Quibas (Abanilla, province of Murcia, Spain) has provided a wide faunal list with more than 60 species. The assemblage of the taxa Arvicola deucalion, Castillomys rivas rivas, Eliomys intermedius, Equus altidens, Capra sp. aff. C. alba and cf. Praeovibos allows the correlation with other Spanish Lower Pleistocene sites in the Betic Cordillera, as Plines 1, Orce 3 and Venta Micena. Therefore Quibas can be located between 1.3 and 1.0 Ma. The palaeoenvironmental features of the area around the karstic cavity and the palaeoclimatic regime are inferred.

Long-Proboscid Flies as Pollinators of Cretaceous Gymnosperms

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.

A rich and diverse tanaidomorphan (Crustacea: Tanaidacea) assemblage associated with Early Cretaceous resin-producing forests in North Iberia: palaeobiological implications

The extinct tanaidomorphan diversity from Early Cretaceous Spanish amber, currently comprising 26 specimens, is reassessed. The fossil family Alavatanaidae Vonk & Schram, 2007, described from Spanish amber, is revised on account of new preparation of type specimens and the discovery of new material. The described tanaidomorphan taxa are classified within the superfamily Paratanaoidea. An emended diagnosis for Alavatanaidae is provided, as well as for the genera Alavatanais Vonk & Schram, 2007 and Proleptochelia Vonk & Schram, 2007, and their respective species Alavatanais carabe Vonk & Schram, 2007 and Proleptochelia tenuissima Vonk & Schram, 2007. Three new species, two of them classified in a new genus each, are described: Alavatanais margulisae Sánchez-García, Peñalver & Delclòs sp. nov., Eurotanais terminator Sánchez-García, Peñalver & Delclòs gen. et sp. nov. and Electrotanais monolithus Sánchez-García, Peñalver & Delclòs gen. et sp. nov. Proleptochelia euskadiensis Vonk & Schram, 2007 is considered a junior synonym of A. carabe, and the genus Proleptochelia, together with its type and only species P. tenuissima, is left without familial placement within Paratanaoidea. Within this superfamily, Alavatanaidae is closely related to Leptocheliidae. Also, morphological variability due to sexual dimorphism in the studied paratanaoids has been determined. Multiple lines of taphonomic and palaeobiological evidence indicate that the Spanish amber tanaids were most likely inhabitants of wet or moist forest floors. http://zoobank.org/urn:lsid:zoobank.org:pub:DC943B18-A01C-412C-8378-C644FEFDA716

Early evolution and ecology of camouflage in insects

Taxa within diverse lineages select and transport exogenous materials for the purposes of camouflage. This adaptive behavior also occurs in insects, most famously in green lacewing larvae who nestle the trash among setigerous cuticular processes, known as trash-carrying, rendering them nearly undetectable to predators and prey, as well as forming a defensive shield. We report an exceptional discovery of a green lacewing larva in Early Cretaceous amber from Spain with specialized cuticular processes forming a dorsal basket that carry a dense trash packet. The trash packet is composed of trichomes of gleicheniacean ferns, which highlight the presence of wildfires in this early forest ecosystem. This discovery provides direct evidence of an early acquisition of a sophisticated behavioral suite in stasis for over 110 million years and an ancient plant–insect interaction.

Two Wasp Families Rare in the Fossil Record (Hymenoptera): Perilampidae and Megaspilidae from the Miocene of Spain

Abstract Three new species of parasitoid wasp are described and figured from Early Miocene (Early Burdigalian) compression fossils from Rubielos de Mora Basin, Spain. These wasps are significant as they are representative of two families exceedingly rare in the fossil record. The first is a species of the family Perilampidae (Chalcidoidea) and, aside from an old and unconfirmed record of an undescribed Perilampus in Baltic amber, is the only documented fossil of this lineage. Perilampus renzii, new species, is described from a single female. The remaining two species are both of the family Megaspilidae (Ceraphronoidea), which is otherwise known in the fossil record solely from a paucity of species preserved in fossil resins. Conostigmus lazaros, new species, and C. chthonios, new species, are distinguished from each other as well as modern congeners.

New Data on Miocene Butterflies in Dominican Amber (Lepidoptera: Riodinidae and Nymphalidae) with the Description of a New Nymphalid

Abstract A new, virtually complete and well-preserved female specimen of Voltinia dramba Hall, Robbins, and Harvey, 2004 (Lepidoptera: Riodinidae) provides new data on this fossil species, and a new fossil species of the Recent genus of Nymphalidae Dynamine Hübner, 1819 (Lepidoptera: Nymphalidae) is described as Dynamine alexae n.sp., on the basis of a male specimen. The two species are preserved in Miocene amber from the Dominican Republic. Dynamine alexae n.sp. represents the first adult nymphalid butterfly found as a fossil in amber. The four taxa of butterflies found up to the present in Dominican amber indicate post-Miocene extinctions in Hispaniola, probably caused by insularization. The butterflies found in Dominican amber do not support a hypothesis of a Gondwanan origin for many butterfly tribes and subfamilies as previously proposed; we conclude that this hypothesis is implausible based on the age of the butterflies as inferred from the fossil record. Some palaeoecologic and taphonomic questions are discussed.

A Review of the Eurasian fossil species of the bee Apis

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.