El Soplao Research Articles

The oldest known riffle beetle (Coleoptera: Elmidae) from Early Cretaceous Spanish amber

Elmadulescens rugosus Peris, Maier et Sánchez-García n. gen. n. sp. is described based on a single specimen from Spanish amber (El Soplao outcrop, Early Albian, Early Cretaceous). The discovery of this specimen in amber is very interesting, since aquatic beetles are not common in fossil tree resin. This fossil pushes back the oldest known specimen of Elmidae from the Eocene (∼40Ma) to at least the Early Cretaceous (∼110Ma).

An evolutionary history embedded in amber: reflection of the Mesozoic shift in weevil-dominated (Coleoptera: Curculionoidea) faunas

Three new weevil (Coleoptera: Curculionoidea) species from Cretaceous amber of Spain (early Albian) and France (late Albian – early Cenomanian) are described. Nemonychidae are represented by two Spanish specimens from the El Soplao and San Just deposits and described as Arra legalovi gen. et sp. nov., Caridae are described from one specimen in the Spanish deposit of El Soplao and named as Albicar contriti gen. et sp. nov., and Curculionidae are documented from one specimen embedded in opaque amber from the French deposit of Archingeay and described as Antiquis opaque gen. et sp. nov. These three new species provide valuable information because they appear to reflect, together with the previously described weevils in Cretaceous ambers, the gradual shift in the dominance of particular curculionoid families across the Cretaceous. Propagation phase-contrast X-ray synchrotron microtomography was utilized to obtain high quality 3D images for some fossils and, at the same time, permit a concise description of them. © 2014 The Linnean Society of London

An evolutionary history embedded in amber: reflection of the Mesozoic shift in weevil-dominated (Coleoptera: Curculionoidea) faunas

Three new weevil (Coleoptera: Curculionoidea) species from Cretaceous amber of Spain (early Albian) and France (late Albian – early Cenomanian) are described. Nemonychidae are represented by two Spanish specimens from the El Soplao and San Just deposits and described as Arra legalovi gen. et sp. nov., Caridae are described from one specimen in the Spanish deposit of El Soplao and named as Albicar contriti gen. et sp. nov., and Curculionidae are documented from one specimen embedded in opaque amber from the French deposit of Archingeay and described as Antiquis opaque gen. et sp. nov. These three new species provide valuable information because they appear to reflect, together with the previously described weevils in Cretaceous ambers, the gradual shift in the dominance of particular curculionoid families across the Cretaceous. Propagation phase-contrast X-ray synchrotron microtomography was utilized to obtain high quality 3D images for some fossils and, at the same time, permit a concise description of them. © 2014 The Linnean Society of London

Two-level systems and boson peak remain stable in 110-million-year-old amber glass.

The two most prominent and ubiquitous features of glasses at low temperatures, namely the presence of tunneling two-level systems and the so-called boson peak in the reduced vibrational density of states, are shown to persist essentially unchanged in highly stabilized glasses, contrary to what was usually envisaged. Specifically, we have measured the specific heat of 110 million-year-old amber samples from El Soplao (Spain), both at very low temperatures and around the glass transition Tg. In particular, the amount of two-level systems, assessed at the lowest temperatures, was surprisingly found to be exactly the same for the pristine hyperaged amber as for the, subsequently, partially and fully rejuvenated samples.

Paleoflood events recorded by speleothems in caves

ABSTRACTSpeleothems are usually composed of thin layers of calcite (or aragonite). However, cemented detrital materials interlayered between laminae of speleothemic carbonate have been also observed in many caves. Flowstones comprising discontinuous carbonate layers form due to flowing water films, while flood events introduce fluviokarstic sediments in caves that, on occasion, are recorded as clayey layers inside flowstones and stalagmites. This record provides a potential means of understanding the frequency of palaeofloods using cave records. In this work, we investigate the origin of this type of detrital deposit in El Soplao Cave (Northern Spain). The age of the lowest aragonite layer of a flowstone reveals that the earliest flood period occurred before 500 ka, though most of the flowstone formed between 422 +69/‐43 ka and 400 +66/‐42 ka. This suggests that the cave was periodically affected by palaeoflood events that introduced detrital sediments from the surface as a result of occasional extreme rainfall events, especially at around 400 ka. The mineralogical data enable an evolutionary model for this flowstone to be generated based on the alternation of flood events with laminar flows and carbonate layers precipitation that can be extrapolated to other caves in which detrital sediments inside speleothems have been found. Copyright © 2014 John Wiley & Sons, Ltd.

Diversity of rove beetles (Coleoptera: Staphylinidae) in Early Cretaceous Spanish amber

Twenty specimens of Staphylinidae (Coleoptera: Polyphaga) were found in the Early Cretaceous Spanish amber. Two new genera and four new species are reported in these samples: Cretasonoma corinformibus in the supertribe Faronitae, and Penarhytus tenebris in the supertribe Pselaphitae, both in the subfamily Pselaphinae; Prosolierius parvus in the subfamily Solieriinae; and Kachinus magnificus in the subfamily Scydmaeninae. Both Prosolierius and Kachinus exemplify the similarity between Cretaceous Spanish amber and Cretaceous Lebanese and Burmese amber, despite their different ages. Pselaphinae is the most common rove beetle subfamily in amber inclusions worldwide, their small size and cryptic litter-dwelling perhaps make them susceptible to being trapped by resin and conserved. Kachinus magnificus, reported in six of the Scydmaeninae specimens from Spanish amber, is the oldest species formally described for the subfamily. Penarhytus tenebris and Prosolierus parvus come from the Peñacerrada I amber deposit, Kachinus magnificus from the El Soplao amber deposit, and Cretasonoma corinformibus is found at both locations, in the Basque-Cantabrian Basin, on the northern Iberian Plate (today the Iberian Peninsula).

New lagonomegopid spiders (Araneae: †Lagonomegopidae) from Early Cretaceous Spanish amber

Four new species belonging to the enigmatic fossil spider family Lagonomegopidae Eskov & Wunderlich, 1995 are described from Albian Spanish amber. Two new genera are created: Spinomegops gen. nov., based on two specimens described as S. arcanus sp. nov. from Álava amber (Peñacerrada I outcrop, Burgos), and S. aragonensis sp. nov. from San Just amber (Teruel); and Soplaogonomegops gen. nov., represented by the type species S. unzuei sp. nov. from El Soplao amber (Cantabria). A single specimen from Álava amber is tentatively assigned to Lagonomegops Eskov & Wunderlich, 1995 and described as L.? cor sp. nov. We confirm the existence of previously contentious numerous tarsal and metatarsal trichobothria on Burlagonomegops alavensis Penney, 2005, and reinterpret the mouthpart morphology of Grandoculus chemahawinensis Penney, 2004. In light of our new data, the family diagnosis for Lagonomegopidae is emended and the family Grandoculidae Penney, 2011 is synonymized with Lagonomegopidae. http://www.zoobank.org/urn:lsid:zoobank.org:pub:67DF253C-4DD8-46B5-8FD4-540D53F6E90B

Description of the male of Megalava truncata Perrichot (Hymenoptera: Megalyridae) in Early Cretaceous amber from El Soplao (Spain)

Description of the male of Megalava truncata Perrichot (Hymenoptera: Megalyridae) in Early Cretaceous amber from El Soplao (Spain)

A new species of the diverse Cretaceous genus Cretevania Rasnitsyn, 1975 (Hymenoptera: Evaniidae) from Spanish amber

Cretevania soplaensis nov. sp. is described from the Early Cretaceous (Albian) amber from El Soplao (Rábago, Cantabria, northern Spain). Although the studied specimen is incomplete, its preserved parts permit us to distinguish it from the previously described species. A discussion about probable sexual dimorphism in Cretevania and possible consequences for the identification of new species based on specimens of unknown or uncertain sex is included.

Snakefly diversity in Early Cretaceous amber from Spain (Neuropterida, Raphidioptera)

The Albian amber from Spain presently harbors the greatest number and diversity of amber adult fossil snakeflies (Raphidioptera). Within Baissopteridae, Baissoptera? cretaceoelectra sp. n., from the Peñacerrada I outcrop (Moraza, Burgos), is the first amber inclusion belonging to the family and described from western Eurasia, thus substantially expanding the paleogeographical range of the family formerly known from the Cretaceous of Brazil and eastern Asia. Within the family Mesoraphidiidae, Necroraphidia arcuata gen. et sp. n. and Amarantoraphidia ventolina gen. et sp. n. are described from the El Soplao outcrop (Rábago, Cantabria), whereas Styporaphidia? hispanica sp. n. and Alavaraphidia imperterrita gen. et sp. n. are describedfrom Peñacerrada I. In addition, three morphospecies are recognized from fragmentary remains. The following combinations are restored: Yanoraphidia gaoi Ren, 1995, stat. rest., Mesoraphidia durlstonensis Jepson, Coram and Jarzembowski, 2009, stat. rest., and Mesoraphidia heteroneura Ren, 1997, stat. rest. The singularity of this rich paleodiversity could be due to the paleogeographic isolation of the Iberian territory and also the prevalence of wildfires during the Cretaceous.

Description of the male of Megalava truncata Perrichot (Hymenoptera: Megalyridae) in Early Cretaceous amber from El Soplao (Spain)

A new fossil of megalyrid wasp recently discovered in Early Cretaceous (Albian) amber from El Soplao (Cantabria, Spain) isdescribed as the male of Megalava truncata Perrichot, 2009, originally described from Peñacerrada I (= Moraza) amber (Bur-gos, Spain). The new specimen permits a more thorough description of the genus Megalava, which was established originallyfrom a single, fragmentary specimen lacking the metasoma, and also permits a discussion on the characters of phylogenetic value for the clade [Megazar + Megalava].

Zaccagnaite-3R, a new Zn-Al hydrotalcite polytype from El Soplao cave (Cantabria, Spain)

We have recently discovered significant amounts of zaccagnaite, a natural Zn-Al-CO3 hydrotalcite in the El Soplao cave (north Spain). The El Soplao zaccagnaite is speleothemic, i.e., formed in the cave, and therefore it represents a new cave mineral. The origin of El Soplao zaccagnaite is related to the diagenesis of Zn- and Al-rich ferromanganese speleo-stromatolites, where it occurs as a porefilling cement that likely precipitated at low temperature (≤ ~11 °C). In some stromatolite layers, the abundance of zaccagnaite crystals is large enough to enable their physical separation. This has allowed us to obtain its X-ray powder-diffraction pattern, infrared spectrum, and differential thermal/ thermogravimetric profiles.

Exceptional preservation of Mn-oxidizing microbes in cave stromatolites (El Soplao, Spain)

Many ferromanganese stromatolites of El Soplao Cave (N Spain) are characterized for the exceptional preservation and high diversity of microbial fossils, probably representing the best example of microbial preservation described in ferromanganese deposits so far.The El Soplao stromatolites are mainly formed by polymetallic Mn-rich oxides with subordinate and variable amounts of detrital material, and consist of both dendritic and laminar microfacies. In both microfacies, microbial forms are abundant in the relatively pure Mn-oxide rich material, whereas they are scarce in areas with significant detrital material. Microbial forms are observed either in cross section, completely embedded in the Mn-oxide-rich matrix, or in three dimensions lining the walls of pores. Based on their morphology, we have separated the most abundant microbial forms into six main morphotypes and six additional submorphotypes, most of which can be assigned to bacteria. Most morphotypes consist of coccoid, coccobacilus, or filamentous forms. Therefore they are not diagnostic of any particular bacterial group. However, the ovoid cells of morphotype B show cylindrical polar protuberances typical of prosthecate alpha-Proteobacteria. On the basis of characteristic morphological features, three submorphotypes of morphotype B can be assigned to three alpha-Proteobacteria genera: Hyphomicrobium, Pedomicrobium, and Caulobacter. This ascription is supported by the well known Mn-oxidizing behavior of both Pedomicrobium and Caulobacter, and by the common presence of Hyphomicrobium in ferromanganese deposits elsewhere.The excellent microbial preservation is partly related to the origin of the ferromanganese oxides, i.e. extracellular precipitation induced by microbial metabolism. Other factors contributing to the good microbial preservation are the relatively low degree of diagenetic alteration, and the relatively high accretion rates of stromatolites compared to other ferromanganese deposits. The generally low degree of diagenesis is likely because the stromatolites have remained relatively stable and at a rather low temperature since they were formed at least 1Ma ago. Still, some stromatolites have suffered diagenetic alteration (partial dissolution and replacement by calcium carbonates and Fe-rich oxides), obscuring or even obliterating their bioforms. The El Soplao case represents an example of how easily biogenic Mn oxides can be altered, and their bioforms blurred, in a relatively short geological time span in spite of being in a relatively stable, alkaline, and low-temperature setting. A geological implication is that the absence of bioforms in other ferromanganese deposits, including rock varnish and Precambrian iron formations, does not disprove their possible biogenic origin, since the high chemical reactivity of biogenic manganese oxides makes them highly vulnerable to diagenesis.

Organic matter of fossil origin in the amberine speleothems from El Soplao Cave (Cantabria, Northern Spain)

Organic matter of fossil origin in the amberine speleothems from El Soplao Cave (Cantabria, Northern Spain)

Black Mn-Fe Crusts as Markers of Abrupt Palaeoenvironmental Changes in El Soplao Cave (Cantabria, Spain)

Black Mn-Fe Crusts as Markers of Abrupt Palaeoenvironmental Changes in El Soplao Cave (Cantabria, Spain)

Biting midges (Diptera: Ceratopogonidae) from the Early Cretaceous El Soplao amber (N Spain)

Three new species, Lebanoculicoides excantabris, Archiaustroconops borkenti, and Atriculicoides szadziewskii are described from the Early Cretaceous (early Albian) El Soplao amber deposit (Rábago, Cantabria, northern Spain). Protoculicoides skalskii Szadziewski and Arillo, found in the other Albian Spanish ambers from Peñacerrada I (in Burgos) and San Just (in Teruel), and Austroconops sp., are identified from this new outcrop. The find of a new species of Lebanoculicoides Szadziewski is especially significant since this genus is considered the basalmost known among ceratopogonids. To date, the new species of Atriculicoides Remm is the oldest occurrence for this genus. A general review of the taxonomy and phylogeny of the family Ceratopogonidae, and the palaeoecological significance and palaeogeographic distribution of its basalmost lineages are given. The new data extend knowledge about biting midges during the Early Cretaceous, a key period for understanding the phylogenetic relationships of the ancient members of the family.

False fairy wasps in Early Cretaceous amber from Spain (Hymenoptera: Mymarommatoidea)

Abstract: The fauna of false fairy wasps (Proctotrupomorpha: Bipetiolarida: Mymarommatoidea) occurring in Early Cretaceous (Albian) amber from north and north‐eastern Spain (Moraza, San Just, and El Soplao outcrops) is described. In total, 12 specimens have been recovered and four species recognized, all new: Alavaromma orchamum gen. nov. and sp. nov. (Alavarommatidae fam. nov.), Archaeromma hispanicum sp. nov. (Mymarommatidae), Galloromma alavaensis sp. nov., and G. turolensis sp. nov. (Gallorommatidae). The study indicates the necessity of revision and maybe fusion of both superfamilies, Mymarommatoidea and Serphitoidea, as the boundaries between them are less and less defined. However, major classificatory rearrangements must await the completion of the cladistic studies presently underway.

A new fossil genus and species of snakefly (Raphidioptera: Mesoraphidiidae) from Lower Cretaceous Lebanese amber, with a discussion of snakefly phylogeny and fossil history

AbstractLebanoraphidia nana gen. et sp.n. is described from the Lower Cretaceous amber of Lebanon and represents the smallest known Raphidioptera. The new taxon is quite similar in its minute size, large compound eyes and wing venation to Nanoraphidia electroburmica (Mesoraphidiidae) from the Lower Cretaceous amber of Myanmar, as well as to 'Mesoraphidia' luzzii from the Upper Cretaceous amber of New Jersey, and Cantabroraphidia marcanoi from the Lower Cretaceous El Soplao amber of Spain. For the species 'Mesoraphidia' luzzii a new genus, Grimaldiraphidia, is erected, because it would otherwise render the genus Mesoraphidia paraphyletic. 'Mesoraphidia' durlstonenesis, 'M.' gaoi, 'M.' heteroneura, 'M.' mitchelli, 'M.' parvula and 'M.' purbeckensis are also transferred to this new genus Grimaldiraphidia. Four Cretaceous amber genera comprise minute specimens and represent a distinct clade within Mesoraphidiidae, for which a new tribe, Nanoraphidiini, is proposed. The phylogeny and fossil record of Raphidioptera is discussed and the suborders Priscaenigmatomorpha and Raphidiomorpha are supported. A revised definition and composition of Mesoraphidiidae (including Cretinocellia) is suggested. 'Siboptera' medialis is transferred to the genus Mesoraphidia. The synonymy of Alloraphidiidae with Mesoraphidiidae is rejected and Alloraphidiinae is restored as separate subfamily that probably represents the sister group of Mesoraphidiinae. The genera Caloraphidia, Styporaphidia and Ororaphidia are transferred to a new subfamily Ororaphidiinae within Mesoraphidiidae. The genus Metaraphidia is excluded from Mesoraphidiidae and attributed to a new monotypic family Metaraphidiidae, which is considered as sister group of Neoraphidioptera (Raphidiidae+Inocelliidae) within the new taxon Euraphidioptera, which is the sister group to Mesoraphidiidae within the new taxon Raphidiformia. Arariperaphidia rochai is transferred to "Baissopteridae" that might rather be a paraphyletic grade of basal stem group representatives.

Manganese stromatolites in caves: El Soplao (Cantabria, Spain)

In the dark regions of caves, the formation of stromatolites is virtually unknown. Although Mn oxide crusts presumably induced by bacteria have been described in some caves, they lack stromatolite features, and the evidence of microbial origin is normally inconclusive. Here we describe for the first time the occurrence of extensive Mn oxide stromatolites formed in the deep interior of a cave. The stromatolites are of decimeter thickness and kilometer extent and show features extremely similar to typical CaCO 3 stromatolites. However, unlike most stromatolites, their biogenicity is supported by the exceptional abundance of fossil microbes. Our data support that the stromatolites were mainly induced by chemolithotrophic Mn-oxidizing microbes, and were formed in a low-gradient water-table stream passage at least ∼1 m.y. ago. The El Soplao stromatolites (Cantabria, Spain) may contribute to increasing our understanding of microbial life in extreme environments, as well as the role of bacteria in the genesis of modern and ancient Mn deposits.

Serphitid wasps in Early Cretaceous amber from Spain (Hymenoptera: Serphitidae)

The diversity of serphitid wasps (Proctotrupomorpha: Serphitoidea) in Early Cretaceous (Albian) amber from Spain is described. Four new species have been found representing the genera Serphites Brues 1937, Aposerphites Kozlov and Rasnitsyn 1979, and Microserphites Kozlov and Rasnitsyn 1979. From the Peñacerrada I (Moraza) outcrop two species are described as Aposerphites angustus Ortega-Blanco, Delclòs, Peñalver and Engel, new species and Serphites lamiak, new species. A single species was found at the San Just (Teruel) outcrop and is described as S. silban, new species. Another single specimen was found in El Soplao (Cantabria) outcrop, described as Microserphites soplaensis, new species. This last specimen is especially interesting in sharing typical serphitid and mymarommatoid characters, giving additional support to the apparent close relationship of both groups.