1) by Andrew Ross (The Natural History Museum, London) 
Email: ajr@nhm.ac.uk 
 

The History, Geology, Age and Fauna (Mainly Insects) of Burmese Amber, Myanmar 
Bulletin of the British Museum (Natural History), Geology Series. 
 

Zherikhin, V.V. & Ross, A.J. .- A review of the history, geology and age of Burmese amber (Burmite). 

Ross, A.J. & York, P.V. .- A list of type and figured specimens of insects and other inclusions in Burmese amber.  

Rasnitsyn, A.P. & Ross, A.J. .- A preliminary list of arthropod families present in the Burmese amber collection at The Natural History Museum, London. 

Sinitshenkova, N.D. .- The first fossil prosopistomatid mayfly from Burmese amber (Ephemeroptera; Prosopistomatidae). 

Shcherbakov. D.E. .- The most primitive whiteflies (Hemiptera: Aleyrodidae; Bernaeinae subfam. nov.) from the Mesozoic of Asia and Burmese amber, with an overview of Burmese amber hemipterans. 

Zherikhin, V.V. .- A new genus and species of Lophioneuridae from Burmese amber (Thysanoptera (=Thripida): Lophioneurina). 

Gaimari, S.M. & Mostovski, M.B. .- Burmapsilocephala cockerelli, a new genus and species of Asiloidea (Diptera) from Burmese amber. 

Lukashevich, E.D. .- Phantom midges (Diptera: Chaoboridae) from Burmese amber. 

Basibuyuk, H.H.; Rasnitsyn, A.P.; Fitton, M.G. & Quicke, D.L.J. .- An archaic new genus of Evaniidae (Insecta: Hymenoptera) and implications for the biology of ancestral evanioids. 

Antropov, A.V. .- Digger wasps (Hymenoptera, Specidae) in Burmese amber. 

Judson, M.L.I. .- Electrobisium acutum Cockerell, a cheiridiid pseudoscorpion from Burmese amber, with remarks on the validity of the Cheiridioidea (Arachnida, Chelonethi). 
 
 

2) by X. Martínez-Delclòs (University of Barcelona) 
Email: delclos@natura.geo.ub.es 
 

Fossil Insects 
Acta Geologica Hispanica  
 

Ansorge, J. & Rasnitsyn, A.P. .- Identity of Prosepididontus calopteryx Handlirsch 1920 (Insecta.- Grylloblattida.- Geinitziidae). 

Azar, D.; Nel, A. & Solignac, M. .- A new Coniopterygidae from the Lebanese amber. 

Engel, M.S. & Grimaldi, D.A. .- A Winged Zorotypus in Miocene Amber from the Dominican Republic (Zoraptera.- Zorotypidae), with Discussion on Relationships of and within the Order. 

Fleck, G.; Nel, A.; De Plöeg, G. & Masselot, G. .- New fossil dragonflies from the Lowermost Eocene amber of France (Insecta, Odonata, Anisoptera). 

Golub, V.B. & Popov, Y.A. .- New cantacaderid bugs from Dominican amber (Heteroptera.- Tingidae, Cantacaderinae). 

Gratshev, V.G. & Zherikhin, V.V. .- New Early Cretaceous weevil taxa from Spain (Coleoptera, Curculionoidea). 

Herczek, A.; Popov, Y.A. & Peñalver, E. .- The first fossil record of cylapinous plant bugs from the Lower Miocene of Spain.- Aragoncylapusmiocaenicus n. gen. and n. sp. (Heteroptera.- Miridae.- Cylapinae). 

Lukashevich, E.D..- Five new Eoptychopteridae (Diptera) from the Mesozoic of Asia. 

Martins-Neto, R.G. .- Remarks on the Neuropterofauna (Insecta, Neuroptera) from the Brazilian Cretaceous with keys for the identification of the known taxons. 

Ortuño, V.M. & Arillo, A. .- Presencia del género Dicerca (Coleoptera, Buprestidae) en el Mioceno Superior de la depresión ceretana (Lleida, NE de España). 

Papier, F.; Nel, A. & Grauvogel-Stamm, L. .- Nouveaux orthopteres (Hagloidea, Insecta) du Trias des Vosges (France). 

Petrulevicius, J. & Martins-Neto, R.J. .- Checklist of South American Cenozoic Insects. 

Poinar, G.O. & Mastalerz, M. .- Taphonomy of fossilized resins.- determining the biostratinomy of amber. 

Poinar, G.O.; Zavortink, T.J.; Pike, T. & Johnston, P.A. .- Paleoculicisminutus (Diptera.- Culicidae) n. gen., n. sp. from Cretaceous Canadian amber, with a summary of fossil mosquitoes. 

Ponomarenko, A. & Martínez-Delclòs, X. .- New Lower Cretaceous Coleoptera from Spain. 

Pulawski, W.J. & Rasnitsyn, A.P..- Cretobestiola, a replacement name for Bestiola Pulawski and Rasnitsyn, 1999 (Hymenoptera.- Sphecidae). 

Rasnitsyn, A.P. .- New genus and two new species of the Lower Cretaceous Digger Wasps from Spain (Hymenoptera.- Sphecidae.- Angarosphecidae). 

Rasnitsyn, A. P. & Ansorge, J. .- Two new Lower Cretaceous hymenopterous insects (Insecta.- Hymenoptera) from Sierra del Montsec (Spain). 

Rasnitsyn, A. P. & Martínez-Delclòs, X. .- Wasps (Insecta.- Vespida= Hymenoptera) from the Early Cretaceous of Spain. 
 

EPHEMERA. 
A new review about, obviously, ephemeropterans (mayflies). It includes systematics, phylogeny, biology, ecology, biomonitoring and palaeontology. The first issue was published in autumn, 1999. The contents of this first volume were:  
 

Editorial: Jean Rapilly; articles: A. Nilsson and Manuel C. Molles. 
 

Thomas, A. & Gaino, E. .- Complementary description of Habrophlebia vaillantorum Thomas, 1986 in comparison with H. fusca (Curtis, 1834)[Ephemeroptera, Leptophlebiidae]. 

Thomas, A. .- Corrections à la Faune des Ephémères d'Europe occidentale: 1.Baetis gemellus Eaton, 1885, sensu Müller-Liebenau, 1969 = B. gadeai n.sp.[Ephemeroptera, Baetidae]. 

Brulin, M.; Thomas, A.; Nel, A. & Nel, J. .- Additions à la Faune des Ephémèresde France (4): Ecdyonurus zelleri (Eaton, 1885) [Ephemeroptera, Heptageniidae]. 

Fontan, B.; Brulin, M. & Masselot, G. .- Redécouverte de Neoephemera maxima (Joly) pour la France [Ephemeroptera, Neoephemeridae]. 

Papazian, M., Brulin, M. & Masselot, G. .- Redécouverte de Isonychia ignota (Walker, 1853) pour la France [Ephemeroptera, Isonychiidae]. 

Haybach, A. .- First records of mayflies from Bas-Rhin (France) [Ephemeroptera]. 

Brulin, M.; Masselot, G.; Stochitch, J.J.; Thomas, A. & Ferlin, P. .- Les Ephémères de Normandie (France) 1. Premiers résultats faunistiques [Ephemeroptera]. 

Masselot, G. & Nel, A. .- Pseudokageronia thomasi gen. nov., sp. nov. from the Upper Miocene of Murat (France) [Ephemeroptera, Heptageniidae]. 
 

More information and subscription: 
http://www.invfmr.org/sub.htm or in the e-mail: mb@invfmr.org 
 
 

1.-Ice-Proximal Paleoclimates at the Wisconsin -Holocene Transition- Paleoentomology. 

http://www.best.com/~workline/c/40/190c.htm 

A project at: U of Colorado Boulder. 

Insect fossils are reliable, sensitive indicators of Quaternary environments, and are especially valuable for delineating intervals of rapid climate change. In North America, many studies have focused on the Wisconsin-Holocene transition at ice-proximal sites. The aim of this research is to synthesize and quantify fossil beetle paleoclimate reconstructions for North America, using the Mutual Climate Range (MCR) method. This is a quantitative method of analyzing the insect fossil data by establishing the modern climate range for each species in a fossil assemblage. MCR analyses will be applied to all published ice-proximal late Wisconsin insect records in North America, and will be used to calibrate the existing data to provide temperature isobar maps for major regions. The MCR results will be compared with those established for European faunas and with North American reconstructions based on palynology. 
 

2.- Mutual Climatic Range Reconstructions of Late Quaternary Climates in Beringia. 

http://www.workpage.com/g/41/126g.htm 

A project at: U of Colorado Boulder. 
Research by: Several P. Investigators, under an NSF award of 25+ months. 

ELIAS, SCOTT ANDERSON, University of Colorado Boulder 

The aim of this grant is to synthesize and quantify paleoclimate reconstructions on the basis of fossil insect data from Eastern Beringia (Alaska, the Yukon Territory) and the Bering Land Bridge using the Mutual Climate Range (MCR) method. The Quaternary insect fossil record is a source of proxy data that provides sensitive, accurate paleoclimatic reconstructions for terrestrial ecosystems. As with any single source of proxy data, fossil insect interpretations cannot provide the complete paleoenvironmental picture. This investigation will promote interdisciplinary cooperation by generating calibrated, quantitative paleotemperature data for fossil beetle assemblages that will be more readily comparable to the reconstructions based on the interpretation of other proxy data, such as pollen response surfaces and transfer functions. 

A principal objective of this investigation will be to establish the nature, timing and intensity of the major climatic transitions of the late Pleistocene. Secondly, this method will be applied in Eastern Beringia to calibrate existing data and provide seasonal temperature reconstructions. 
 

3.- Paleogenetics of Quaternary Coleoptera. 

http://www.workpage.com/g/16/104g.htm 

A project at: NM Institute of Mining & Tech. 
Research by: One P. Investigator. 

REISS. 

A central issue in biogeographic research is the response of organisms to climatic changes. This research project addresses the question of the molecular genetic response of organisms to climate change. It is proposed that paleogenetics, the combination of paleontological and genetical techniques, will detect genetic changes over time and will facilitate the measurement of the force of climate change as an agent of natural selection. 

The late Quaternary is a epoch that exhibits climatic warming and has a good fossil record. Especially well represented are species of Coleoptera, many of which are present in extant populations (Elias 1994). DNA sequence analysis on extant populations and fossil assemblages from this period of climate change will allow an assessment of the effect of climate change on the genetic constitution of natural populations. This research will contribute to predictions regarding future global warning. This project will continue molecular biogeographic work on alpine-arctic beetle species begun as a postdoctoral research project (Reiss, unpublished data). Dr. A. Ashworth and Dr. D. Schwert (Quaternary Entomology Lab, Fargo, ND) will continue to collaborate and provide both extant and fossil specimens. Preliminary efforts at amplifying DNA from fossil chitin collected from bogs in the Midwestern United States. 
 
 

by M. Mostovski (Paleontological Inst., Moscow, Russia) 
Email: contrakt@mail.sitek. ru 

Summer is indeed a good time for travelling for it is hardly possible to stay and work in the concrete jungle when temperature rises up to 35 degrees in the shade. Moreover, the great expedition to Baissa and some other remote fossil sites seems to have failed this year. So we decided to spend a couple of weeks in the field collecting insects, both fossil and Recent. We is Lena Lukashevich with her son Sergei, Tania Oudatchina, Natalia Zavialova, Natalia Gordenko, and I.  

There are several nice places not far from Moscow which are of particular interest from the palaeontological point of view. The locality of Nedubrovo is one of them. It was discovered by the geologist V.R. Lozovsky about thirty years ago, but only four insect fossils were subsequently found by geologists and paleobotanists. The outcrop on the left bank of the Kichmenga River very near Nedubrovo Village, Vologda Region, is represented predominantly by grey and red members. Insects are mainly found in the lower member and occur at several levels. The most diverse assemblage is recorded in the marl lens at the junction between the grey and red beds.  A very few insect fragments have also been discovered in carbonate concretions at the base of the red member. The age of the formation is most probably earliest Triassic, but the latest Permian can not be ruled out.  In total, 43 specimens have been collected in course of intensive fieldwork, viz. Blattodea (3), Coleoptera (1), Homoptera (9), Grylloblattidae (8), Mecoptera (5), Insecta incertae sedis (17). Besides insects, rare conchostracans, ostracods, plant fragments, and pollen are found. Tetrapod bones are recorded in the overlying conglomerates. The fossils await detailed study, and everyone is looking forward to visit this and other fossil sites next year. 
 
 

VII International Symposium on Mesozoic Terrestrial Ecosystems, Buenos Aires (Argentina) 
September 26 - October 1, 1999. 

by: Xavier Martínez-Delclòs (1), Enrique Peñalver-Mollá (2) & Alexander Rasnitsyn (3) 
1) Email: delclos@natura.geo.ub.es2) Email: penalver@uv.es 3) Email:rasna@glasnet.ru 

Since 1996, the Lower Cretaceous (Aptian) amber of Álava (Spain) has contributed approximately one thousand five hundred fossil arthropods, mainly insects, the majority very little in size.  In terms of the number of specimens and diversity, the largest group is Diptera (> 55 %), and the second largest group is Hymenoptera with approximately two hundred fifty individuals (24 %). In general, the insect fossil assemblage found in the Álava amber is similar, both in present groupings and relative abundance, compared to the rest of the Cretaceous ambers. 

Two groups of Hymenoptera have been discovered, Symphyta and Apocrita. Symphyta is represented by a single specimen of Anaxyelidae, the first record of Symphyta in the Cretaceous ambers. The Apocrita is divided into two groups Parasitica and Aculeata, on the basis of their eating habits and behaviour, but this distinction is not always possible. Parasitica make up 95 % of the total Hymenoptera specimens found in this amber and belong to 9 families: Orussidae, Trigonalidae, Evaniidae, Megaspilidae, Stigmaphronidae, Scelionidae, Serphitidae, Mymarommatidae and Braconidae. Scelionidae dominate with 48 % of specimens collected, and Stigmaphronidae are the next largest family with 8 % . Aculeata make up 4 %  and belong to three or four families: Sphecidae, Chrysididae, Bethylidae and possibly a new family of  Chrysidoidea. 

The records of Orussidae, Evanidae and Mymarommatidae are the oldest for these families which were not previously known before the Upper Cretaceous, or Evanidae the Eocene. In contrast, the record of Anaxyelidae is the latest one for this family, except for a sole living species which survived in SW North America. Serphitidae and Stigmaphronidae are extinct groups known exclusively from the Cretaceous. 
 

XV Jornadas de Paleontología, Madrid (Spain) 
28 - 30 October 1999. 

Amber from the Lower Cretaceous of Peñacerrada (Alava, Spain)*

by: Xavier Martínez-Delclòs (1), Antonio Arillo(2), Vicente Ortuño (3)  y Enrique Peñalver (4) 

1) Email: delclos@natura.geo.ub.es 2) Email: aarillo@teleline.es 3) Email: penalver@uv.es 
4) Email: ildotre@retemail.es 

Amber is fossilized resin produced as part of metabolic or protective processes by some trees, mainly conifers and Leguminosae. Once the resin is exuded to the atmosphere it hardens and through aging it polymerizes. Preservation of small organisms trapped in the amber is excellent; some characteristics are so well preserved that comparison with extant flora and fauna is usually possible. 

In this paper we use the term "amber" to refer to the Spanish resin although a lot of different names have been proposed depending on the botanical origin, age, chemical and physical characteristics, etc. of fossil resins (Vavra, 1993). 

Although amber was known a long time ago from the Sierra de Cantabria mountains only very recently have organic inclusions been found. This amber has become, in a short time, one of the most important ambers in the world, due mainly to the huge number of inclusions and its diversity. 
Lower Cretaceous fossiliferous ambers are rare; apart from the Spanish amber, only four more localities are known: Jezzine and Baabda (Lebanon), Wadi Zarka (Jordan), Isle of Wight and Hastings (U.K.) and Golling (Austria) (Alonso et al. 2000). 

In Spain, fossil insects from Lower Cretaceous sedimentary rocks were previously known as compressions, but the amber insect fauna is quite different, usually with smaller specimens which are difficult to find in sedimentary rocks. This feature makes it possible to have a broader view of insect diversity during the Lower Cretaceous, a very interesting period due to the radiation of the angiosperms and the extinction of several groups. 
 

Geology 

Amber outcrops in Alava are located in the central region of the northern slope of the Sierra de Cantabria mountains, approximately 30 kms south of the city of Vitoria, near the village of Peñacerrada (there are two known outcrops, Peñacerrada I and Peñacerrada II). The amber beds comprise black clays and medium-grained feldspathic sandstones together with organic matter and sulphur. These sediments were deposited on a delta plain where some small paralic basins developed during the Lower Albian producing seams of coal. Alpine compression caused folding and faulting of the material, so correlation of even very closely located outcrops is difficult. All the amber was found in sediments belonging to the Nograro Formation which is located between the Montoria Formation (Valanginian-Barremian) and the Arenas de Utrillas Formation (Upper Albian in this region). However, in some places, the latest levels of the Nograro Formation make a lateral transition to the Arenas de Utrillas Formation. The amber-bearing sediments were possibly formed by avulsion (channel rupture) during flooding which caused the deposition of clays, sandstones and amber (amber density is between 1.01 and 1.07) or perhaps the sediments represent deposits in marginal bays. Contact with marine waters is highly probable due to the presence of dinoflagellate cysts in the sediments. 
 

Origin of the amber 

Dr. Grimalt (in Alonso et al. 2000) studied the chemical composition of the amber and suggested the genus Agathis (Araucariaceae) as its botanical origin due to the presence of compounds like kaurenes. Podocarpaceae, Burseraceae, Cupressaceae, Dipterocarpaceae and the genus Hymenea are excluded from its possible origin due to the absence of some specific molecules. The analysis of the amber shows a strong affinity with Baltic amber (which shows an araucarian origin also); however, there is a basic difference between both ambers perhaps due to their different ages. 
Palynological analysis also suggests an araucarian origin of this amber (Dr. Barrón in Alonso et al. 2000) due to the presence of inaperturate pollen grains. This study revealed the presence of a high number of spores belonging to Bryophyta and Pteridophyta together with inaperturate, bisaccate, circumsulcate, monosulcate and polysulcate non-tectate and tectate tricolpate pollen grains. These have been assigned to Coniferophyta, Cycadoideophyta, Gnetophyta and Spermatophyta. The palynological association may indicate an age no younger than Middle Albian. 
 

Inclusions 

The Peñacerrada outcrops have yielded, in a short period, a lot of organic inclusions (ca. 2000), normally very small arthropods and mainly Hexapoda. There are also present both Crustacea and Chelicerata.  Crustacea are represented by amphipods and isopods (Oniscoidea) and among Chelicerata we have found mites belonging to the order Actinotrichida (several Actinedida and one oribatid that will be described as a new species, genus and family). There are also several spiders, some of them belonging to new families (Wunderlich, pers.com.). 

We usually find quantities of organic matter as inclusions that could represent arthropod pellets or eggs. Non-arthropod inclusions are cryptogram plant remains, undetermined leaves, and we have also found several downy feathers and one contour feather belonging to birds or avian dinosaurs.  

Among the Hexapoda, the best represented orders are Diptera and Hymenoptera, but there are also eleven other orders present:  Collembola, Thysanura, Orthoptera, Blattodea, Psocoptera, Thysanoptera, Hemiptera, Neuroptera, Trichoptera, Lepidoptera and Coleoptera. Most of them belong to Ectognatha (Insecta s.str.); among Entognatha, only Collembola are present. Only two specimens of Thysanura (s.lato) have been found perhaps due to their lack of wings as flying insect orders occur more frequently in amber. Orthopteroid insects are only represented by some fragmentary remains and Blattodea are present with several juvenile stages and isolated wings and legs. The order Psocoptera is very well represented (both nymphs and adults). Among Psocatropetae we have found a new species, genus and family ; specimens are so well preserved that a very detailed study of the mouth, genitalia, espermatheca and wing microsetation was possible. The newly described family is close to Prionoglaridae and Psyllipsocidae of which extant members are cave dwellers. This reinforces the hypotheses that hypogean fauna had a remote origin from Mesozoic tropical forests which disappeared during the early Tertiary. Other Psocoptera are also present belonging to the fossil subfamily Empherinae (Atropetae), probably representing a new genus and species (two specimens) and a new species of a  still undetermined genus (two specimens).  Hemipteroid insects are also present belonging to the orders Hemiptera (both Homoptera and Heteroptera, Geocorisae) and Thysanoptera. Only two small but very well preserved specimens belong to the order Neuroptera (s.lato).  

Beetles (Coleoptera) are frequent, but normally are difficult to study due to the presence of  emulsion around the body of the inclusions. The suborder Polyphaga has been recorded with representatives of the superfamilies Staphylinoidea and Elateroidea. 

The order Diptera is the best preserved in the Peñacerrada amber (around 50% of all inclusions); both Nematocera and Brachycera are frequent. Tipulomorpha are represented by several big fly inclusions, possibly belonging to the family Limoniidae (at least three different forms). Other Nematocrea comprise the families Mycetophilidae, Keroplatidae (two specimens belonging to two different species), Cecidomyiidae (two new genera), Psychodidae (one specimen), a lot of Phlebotomidae (with perhaps two different forms), Chironomidae, Scatopsidae  and Anisopodidae. The family Ceratopogonidae is currently being studied, Szadziewski & Arillo (1998) having described  two new species, Protoculicoides skalskii (a genus known from Lebanese amber) with a long proboscis (it could represent a dinosaur blood-sucking species) and Archiaustroconops alavensis (a genus previously known from Canadian and Lebanese ambers). Among the Brachycera there is also high diversity. There are two specimens belonging to Tabanomorpha (possibly to the family Rhagionidae). Another big specimen (unfortunately without the head preserved) could perhaps be related to the family Therevidae. The most frequently preserved group of Brachycera is Empidoidea. Waters & Arillo (1999) described a new genus and species (Alavesia subiasi) and a very numerous group of inclusions which may be related to the fossil genus Microphorites Hennig, 1971, known from Lebanese amber. A third group of Empidoidea (at least four specimens) could be related to the Lebanese amber fossil genus Chimeromyia Grimaldi & Cumming, 1999. The family Lonchopteridae is also frequent but the specimens are still undescribed. Finally, Arillo & Mostovski (1999) described Euliphora grimaldii, a new genus and species of a fly belonging to the fossil subfamily Prioriphorinae (Phoridae). 

The order Hymenoptera is the second most numerous group of insects in the Alava amber with around 200 specimens (the greater part of them being parasitic forms). Only one specimen belongs to the Symphyta (family Anaxyelidae) being the first symphytan ever described from Cretaceous amber. The rest of the specimens belong to the Apocrita. Among the Parasitica, 9 families are recorded: Trigonalidae, Braconidae, Evaniidae, Orussidae, Serphitidae, Megaspilidae, Scelionidae, Stigmaphronidae, and "Mymarommatidae".  There are three families recorded belonging to the Aculeata: Sphecidae, Bethylidae and Chrysididae (the most frequent - seven specimens). The commonest family Scelionidae (Diaprioidea) is present with at least five different forms (more than 2/3rds of all the Hymenoptera found). They  are minute organisms (not exceeding 1.5 mm in length), with heavily sculptured thoraces and antennae with 13 or 14 flagellomeres. Their wing venation is highly variable. This family is common to nearly all insect associations found in Cretaceous ambers. Among the Parasitica there are two families that only appear in the Cretaceous: Serphitidae and Stigmaphronidae. There are only three known genera of Serphitidae and two of them appear at Peñacerrada: Serphites and Aposerphites. Many of the Hymenoptera families are very interesting from a phylogenetic point of view as their age coincides with the diversification of their groups (all families found appear for the first time in the Lower Cretaceous). For example, Megaspilidae have primitive wing venation patterns compared with extant species as veins C and R are not fused as a solid bar which is a feature not seen before in any representative of this family. Another example is the only specimen of "Mymarommatidae": apart from different autapomorphies, its characteristics are common to Mymaridae and Mymarommatidae, so this specimen could belong to the sister group of Mymaridae + Mymarommatidae (both families appear for the first time in the Upper Cretaceous). Specimens belonging to the families Orussidae and Evaniidae are the oldest known. The previously oldest known Orussidae are from the Upper Cretaceous, and the oldest known Evaniidae from Eocene Baltic amber. 

Amber sometimes preserves "frozen" relationships between species (something very rare in compression fossils). Our amber has different examples of it. Two pieces contain parasitic mites (possibly Erythraeisae) attached to their hosts (one Chironomidae and one Microphoridae). In another piece, one keroplatid is being parasitized by a wasp (Stigmaphronidae). The above mentioned "mymarommatid" is also interesting because its post-mortem ejaculation is preserved (the oldest known in the fossil record)! 

References 

Alonso,J., Arillo,A., Barrón,E., Corral,J.C., Grimalt, J., López, J.F., López del Valle, R., Martínez-Delclòs, X., Ortuño, V., Peñalver, E. & Trincao,P.R.  (2000).- A new fossil resin with biological inclusions in Aptian deposits from the Sierra de Cantabria (Alava, Northern Spain, Basque-Cantabrian Basin). Journal of Paleontology, 74(1):158-178.  

Arillo,A. & Mostovski, M. (1999, in press).- A new genus of Prioriphorinae (Diptera, Phoridae) from the Lower Cretaceous amber of Alava (Spain). Studia Dipterologica, 6(2):  

Szadziewski,R. & Arillo,A. (1998).- Biting midges (Diptera: Ceratopogonidae) from the Lower Cretaceous amber from Alava, Spain. Polskie Pismo Entomologiczne, 67(3/4): 291-298. 

Vavra, N. (1993).- Chemical characterization of fossil resins ("amber")- A critical review of methods, problems and possibilities: determination of mineral species, botanical sources and geographical attribution. Abhandlung der (Österrichischen) Geologischen Bundesanstalt, A. 49: 147-157. 

Waters,S.B. & Arillo,A. (1999).- A new Hybotidae (Diptera, Empidoidea) from Lower Cretaceous amber of Alava (Spain). Studia Dipterologica, 6(1): 59-66.