Spermatozoa from the supertribes Lasiopteridi and Stomatosematidi (Insecta, Diptera, Cecidomyiidae): ultrastructure data and phylogeny of the subfamily Cecidomyiinae

Spermatozoa from seven gall-midge species, representing the supertribes Lasiopteridi and Stomatosematidi, have been examined by electron microscopy and compared to the spermatozoa of 30 previously examined gall-midge species of the subfamily Cecidomyiinae. Derived characteristics of all examined representatives of this subfamily are the lack of acrosome and the absence of accessory tubules in their axoneme. The sperm axoneme of Didactylomyia has a unique '9 + 5 pattern', i.e. with 9 outer doublets and 5 inner singlet microtubules. Unlike other members of Cecidomyiinae, Didactylomyia has retained some plesiomorphic traits, namely crystal containing mitochondria and a homogeneously condensed nucleus. Stomatosema has a 10 + 0 axoneme and an irregular nuclear condensation. Thus, Didactylomyia may serve as an useful outgroup for phylogenetic analysis within the subfamily Cecidomyiinae. The supertribe Stomatosematidi is a paraphyletic assemblage. Nearly all members of Lasiopteridi, Ozirhincus, Arnoldiola, Brachineura and Ledomyia , have a synapomorphic character in the great number of microtubules in parallel to the axoneme. A notable exception is Rhizomyia , which shares certain apomorphic traits with several genera that have previously been classified within the Cecidomyiidi, i.e. Contarinia, Allocontarinia, Lestodiplosis and Myricomyia. Moreover, these genera have a flat sperm tail and microtubular doublets located close to the cell membrane, both characteristics that differ markedly from the very peculiar sperm tail found in other members of Cecidomyiidi.
Cladistic analysis of sperm characters suggests that the supertribe Cecidomyiidi is a polyphyletic taxon and supports the existence of a sister-group relationship between the supertribe Lasiopteridi and the genera Rhizomyia, Contarinia, Allocontarinia, Lestodiplosis and Myricomyia.     

Beiträge zur kenntnis fossiler trauermücken aus Sächsischem Bernstein. teil II. Drei neue sciariden aus tertiär-Harzen des bitterfelder braunkohlereviers (insecta,diptera, sciaridae)

Examination of 278 pieces of fossil resins from the lower Miocene Saxonian amber (opencast mining Goitsche/Bitterfeld/Germany) yielded to a total of 60 Sciarids in 29 pieces of amber. They belong to 9 species from 3 genera. The speciesEpidapus Primarius, Trichosia (Palaeotrichosia) voelsgeni andTrichosia (Palaeotrichosia) kedingi are new. The other species are known also from Baltic amber.     

Fossil water striders from the Middle Eocene fossil sites of Eckfeld and Messel,Germany (Hemiptera,Gerromorpha)

Water striders (Hemiptera, Gerromorpha) are a very distinct ecological group specially adapted for life on the water surface. The present paper reports on four species of Gerromorpha from the Middle Eocene fossil sites of Eckfeld and Messel describingLutetiabates eckfeldensis n. gen. et n. sp.,Cylindrobates messelensis n. gen. et n. sp. (both Gerridae), and two nymphs most probably of the genusGerris. The record of two new members of Gerridae from the Paleogene as well as the hitherto known Gerromorpha from fossiliferous resins document a distinctly higher diversity of water striders within die European Paleogene than today. Lastly, comments are made on the fossil history as well as on the palaeobiological and palaeobiogeographical significance of the faunas.     

Protist-like inclusions in amber, as evidenced by Charentes amber

The mid-Cretaceous amber of France contains thousands of protist-like inclusions similar in shape to some ciliates, flagellates and amoebae. The sheer abundance of these inclusions and their size variation within a single amber piece are not concordant with true fossil protists. French amber is coniferous in origin, which generally does not preserve well protists without cell walls. Thus, it would be surprising if French Cretaceous amber had preserved millions of protists. Here, we present a survey of the protist-like inclusions from French amber and attempt to elucidate their origins.Diverse Cretaceous ambers (from Spain, Germany and Lebanon), also derived from conifer resins, contain thousands of protist-like inclusions. In contrast, Tertiary ambers and modern resins are poor in protist-like fossils. This suggests these inclusions originated from early Cretaceous plant resins, probably secreted with the resin by trees that did not survive after the Cretaceous (such as the Cheirolepidiaceae). A review of the recent literature on amber microfossils indicates several protist-like inclusions that are unlikely to have a biological origin have already been described as real fossil protists. This is problematic in that it will bias our understanding of protist evolution.     

Fossil water‐penny beetles (Coleoptera: Psephenidae: Eubrianacinae) from the Eocene of Europe,with remarks on their phylogenetic position and biogeography

Abstract: A species of water‐penny beetles is recorded from larval instars from the Middle Eocene Messel pit fossil site in Germany. This species clearly belongs to the psephenid subfamily Eubrianacinae, but its precise systematic affinities remain unclear. It is the second fossil species of this taxon recorded from Europe. The holotype of the first fossil species, Eubrianax vandeli Bertrand and Laurentiaux, 1963, is lost. The high number of fossil specimens from Messel allowed discussion of stratigraphic and spatial occurrence of the eubrianacine species in the Messel pit, but its larval ontogeny could not be unravelled. Because of the high number of fossils and their wide occurrence, it is inferred that the species from Messel gen. sp. 1 was an autochthonous faunal element of the Eocene Lake Messel, which might indicate that some parts of the former Lake Messel had a shore area with stones. The analysis of the phylogenetic position of both Eocene eubrianacine species showed that their phylogenetic placement cannot be resolved because preservational influences limit the evaluation of characters. The historical biogeography of Psephenidae and Eubrianacinae is analysed and discussed. The fossil record shows that psephenid beetles have fossil members occurring outside their current distribution range, so interpretations of their biogeography based only on extant members can be misleading.     

Review of the Late Eocene Encyrtidae (Hymenoptera,Chalcidoidea) with a description of the first fossil genus with filum spinosum

Glaesus gibsoni gen. et sp. nov. and Eocencnemus gedanicus sp. nov. are described from materials stored in the amber collection of the University of Gdańsk. Eocencyrtus zerovae Simutnik, 2001 is for the first time recorded in the Baltic amber. The encyrtids recorded in Eocene ambers are reviewed, and a key to the known genera is given. The fossil Encyrtidae cannot be placed with confidence in any of the established subfamilies. Their comparative morphology is analyzed. One of the diagnostic characters of the subfamily Encyrtinae, the presence of the filum spinosum, is recorded for the first time for fossil encyrtids (in G. gibsoni).     

Paleobotanical remains from the Paleocene–lower Eocene Vagadkhol Formation, western India and their paleoclimatic and phytogeographic implications

A small assemblage of macro- and micro floral remains comprising fossil leaf impressions, silicified wood, spores, and pollen grains is reported from the Paleocene–lower Eocene Vagadkhol Formation (=Olpad Formation) exposed around Vagadkhol village in the Bharuch District of Gujarat, western India. The fossil leaves are represented by five genera and six species, namely, Polyalthia palaeosimiarum (Annonaceae), Acronychia siwalica (Rutaceae), Terminalia palaeocatapa and T. panandhroensis (Combretaceae), Lagerstroemia patelii (Lythraceae), and a new species, Gardenia vagadkholia (Rubiaceae). The lone fossil wood has been attributed to a new species, Schleicheroxylon bharuchense (Sapindaceae). The palynological assemblage, consisting of pollen grains and spores, comprises eleven taxa with more or less equal representation of pteridophytes, gymnosperms, and angiosperms. Angiospermous pollen grains include a new species Palmidites magnus. Spores are mostly pteridophytic but some fungal spores were also recovered. All the fossil species have been identified in the extant genera. The present day distribution of modern taxa comparable to the fossil assemblage recorded from the Vagadkhol area mostly indicate terrestrial lowland environment. Low frequency of pollen of two highland temperate taxa (Pinaceae) in the assemblage suggests that they may have been transported from a distant source. The wood and leaf taxa in the fossil assemblage are suggestive of tropical moist or wet forest with some deciduousness during the Paleocene–early Eocene. The presence of many fungal taxa further suggests the prevalence of enough humidity at the time of sedimentation.     

Serpulids and other calcareous tube-dwelling encrusting polychaetes from the Early Cretaceous Agrio Formation (Neuquén Basin,Argentina)

Serpulids and other related tube-dwelling polychaetes are often ignored when found as fossil remains. They are, however, a widespread and important group today, and abundant literature has been published on them. Knowledge of fossil serpulids is centered on European material, and little has already been done on South American fossil calcareous tubes. In this paper, seven serpulid and sabellid morphotypes are described from the Early Cretaceous marine Agrio Formation of Argentina, revealing a diversity of worms recorded as encrusters on bivalves, ammonites and corals. Sabellids are represented by Glomerula cf. serpentina. Serpulids are represented by two subfamilies: “Serpulinae” includes Mucroserpula mucroserpula, Parsimonia antiquata, Placostegus cf. conchophilus, Propomatoceros semicostatus and P. sulcicarinatus; Spirorbinae is represented by heavily worn tiny coiled tubes assigned to ?Neomicrorbis. Serpulids and sabellids are one of the main components of the mollusk-encrusting fauna recorded in the Agrio Formation, along with small oysters but much more diverse. They are most commonly found as post-mortem encrusters, but some cases of unquestionable living interaction are also found, such as serpulid tubes embedded on coral branches. They are often overgrown by bryozoans, and sometimes by oysters; they frequently occur aggregated.     

Pollination of Kadsura longipedunculata (Schisandraceae), a monoecious basal angiosperm, by female, pollen-eating Megommata sp. (Cecidomyiidae: Diptera) in China

The plants of Kadsura longipedunculata (Schisandraceae) are monoecious and possess either red or yellow male flowers (the androecium), with yellow tepals, and yellow female flowers. All flower types simultaneously produce heat and floral odours (dominated by methyl butyrate) throughout a 4–5-h nocturnal period. The flowers are pollinated only by female, pollen-eating Megommata sp. (Cecidomyiidae). Pollen is the only reward, and female flowers use the same attractants as male flowers but offer no food (pollination by deceit). Open pollinated flowers in nature varied in fruit set from 8 to 92%. Megommata (subfamily Cecidomyiinae, supertribe Cecidomyiidi), consists of six described species, which feed on Coccoidea (scale insects) and are distributed worldwide.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 523–536.     

Terpenoids as chemosystematic markers in selected fossil and extant species of pine (Pinus, Pinaceae)

The compositions of terpenoids from the seed cones and resins of selected fossil and modern species of pine ( Pinus , Pinaceae) were analysed using gas chromatography-mass spectrometry (GC-MS) to study the preservation of chemosystematic markers (biomarkers) in fossil conifers. Diterpenoids of the abietane, pimarane, isopimarane, and labdane types are the major components in the solvent extracts of all fossil and extant pines. Mono- and sesquiterpenoids of the bornane and cadalane classes and two phytosterols were also identified. The terpenoid patterns of the fossil species largely match the terpenoids observed in modern pines. The characteristic features of the fossil and extant Pinus species are abietane-, pimarane-, and isopimarane-type diterpenoids with a high abundance of abietic acids. Several biomolecules were preserved unaltered in the Eocene and Oligocene pine cones. In addition to the biomolecules, the fossil pines contain a series of degradation products (geomolecules) that were generated from their biological precursors before and after burial. The generation of the geomolecules is governed by various oxidative and reductive processes, such as microbial degradation and clay catalysis. In conclusion, the comparative analysis of solvent-extractable biomarkers in fossil and related extant species is a valuable tool for (palaeo)chemosystematic studies of conifers.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 129–140.     

Diverse fossil amoebae in German Mesozoic amber

Fossil amoebae are very rare, although their evolutionary history extends back into the Proterozoic. The Cenomanian amber of Schliersee (southern Germany) is very rich in micro-organisms and contains the highest diversity of fossil freshwater rhizopods (Gymnamoebia and Testacealobosia) yet discovered. Altogether seven testate amoebae and one gymnamoebian species are recorded from this Mesozoic amber. The four newly discovered taxa described in this paper can be assigned to the extant species Centropyxis delicatula , Centropyxis hirsuta , Phryganella acropodia and Phryganella paradoxa . Over 200 individuals of Phryganella paradoxa are preserved. Together with their syninclusions, the amoebae are species of limnetic or limnetic–terrestrial microcoenoses. The presence of 100-myr-old fossils with extant representatives suggests evolutionary stasis of these freshwater amoebae. However, not all modern testacean families have been recorded from Mesozoic limnetic habitats. Our experimental studies verify that naked and testate amoebae can be embedded in resins.     

A large Percrocutid Carnivore from the Late Miocene (ca. 10–9 Ma) of Nakali, Kenya

The presence of a large hyaenoid (Hiperhyaena sic leakeyi) from the Late Miocene (Vallesian equivalent) deposits at Nakali, Kenya, was first recorded in 1974, but the fossil on which the announcement was based was not described or figured, nor was a type specimen or type species nominated. The generic and specific names are thus nomina nuda. Howell and Petter (1985) described Hyperhyaena leakeyi, and credited the generic and specific names alternatively to Aguirre and Leakey (1974) and Aguirre and Crusafont in 1974 (the latter paper was never published). Howell and Petter are in fact the authors of both the generic and the specific names. Later in the same paper, Howell and Petter (1985) rejected the name Hyperhyaena and classified the species leakeyi in Allohyaena (Dinocrocuta). The purpose of this paper is to provide more information about the fossil and to discuss its relationships to other percrocutids. It is concluded that it belongs to the genus Percrocuta Kretzoi, 1938, being morphologically similar to the type species Percrocuta carnifex (Pilgrim, 1913) from the Siwaliks of Pakistan.     

Discovery of fossil Ayu (<Emphasis Type="Italic">Plecoglossus altivelis</Emphasis>) from the Upper Miocene of Shimane Prefecture,Japan

The Ayu, Plecoglossus altivelis, comprising three subspecies, is the only species in the genus Plecoglossus in the family Osmeridae. Here, we describe for the first time the discovery of fossil specimens of P. altivelis from the Upper Miocene sediment of Matsue, Shimane Prefecture, Japan. The fossil individuals are subadult and have comb teeth in the second and third generations. These fossil specimens are clearly similar to the recent P. altivelis, the former’s meristic characters being included in the three recent subspecies. In terms of numbers of pectoral fin rays and vertebrae, the fossil specimens are more similar to the subspecies Plecoglossus altivelis ryukyuensis than the other subspecies, but they also show different dorsal fin shapes and anal fin ray counts. This discovery of fossil P. altivelis indicates the persistence of the species for at least 10 million years, from the Late Miocene to the present.     

Gall midges of the supertribe stomatosematidi (Diptera,Cecidomyiidae) in the Palaearctic region,with descriptions of new taxa from the late Eocene Rovno Amber. 2. The genera <Emphasis Type="Italic">Didactylomyia</Emphasis> and <Emphasis Type="Italic">Rovnodidactylomyia</Emphasis> gen. n.

One new genus (Rovnodidactylomyia Fedotova et Perkovsky, gen. n.) and four new species (Didactylomyia dlusskyi sp. n., Rovnodidactylomyia zosimovichi gen. n. et sp. n., R. sidorenkoi sp. n., and R. iconica sp. n.) are described from an amber sample of the late Eocene Period (Rovno District, Ukraine). Two species from a Baltic amber sample of the late Eocene Period, described earlier in the genus Bryocrypta, are attributed to the genus Rovnodidactylomyia (R. girafa (Meunier, 1904) comb. n. and R. capitosa (Meunier, 1904)). The first fossil species of the genus Didactylomyia is described for the first time; two contemporary Palaearctic species are recorded. Keys to the species of the genus Didactylomyia are given.     

Dammar resin from the Eocene lignite of Bengal Basin,eastern India: Terpenoid composition and botanical origin

The chemical composition of fossil resins from Middle to Late Eocene lignite samples of the western margin of Bengal Basin, India, has been chemically analyzed to infer their botanical affinity. The terpenoid content of the resins has been characterized using gas chromatography–mass spectrometry (GC–MS). Sesquiterpenoid and triterpenoid components show close affinity with those in extant dammer (Dipterocarpaceae) resin (class II) and indicate the common occurrence of dipterocarps in the forest growing under warm tropical climate in the area at that time. Rich palynofloral assemblages dominated by Dipterocarpaceae pollen grains recovered from the lignite samples corroborate the chemical data.     

Biodiversity dynamics and their driving factors during the Cretaceous diversification of Spatangoida (Echinoidea, Echinodermata)

Variations in recorded diversity over time present a scrambled signal that is modulated by a large number of variables: the potential of particular life forms to generate evolutionary innovations, external constraints induced by the environment in its broad sense, the heterogeneity of the fossil record and the analytical artefacts due to sampling bias. A key question is how to characterise and quantify the separate input of any given factor in the overall diversity signal. This paper explores the structure of diversity data for spatangoid heart urchins and the sensitivity of recorded diversity to different factors of analytical bias (length of geological periods, proportion of palaeogeographical realms explored, accessible area of outcrops and historical determinism). Unexpectedly, recorded diversity of spatangoids is not proportional to the duration of stages. Bias implied by time scale is negligible compared to bias of sampling or historical determinism. Diversity at any given time is dependent on its recent history (autocorrelation). For spatangoids, a high correlation between diversity at time t_i and t_i−1 suggests that recorded diversity has an evolutionary significance. A nearly constant rate of diversification is hypothesised for the Cretaceous. A relative poor fossil record during the Turonian and the Coniacian interrupts the main trend of diversification. The number of species counted for a single time interval depends on the number of palaeogeographical realms considered. In conjunction with ecological and phylogenetic data, this relation suggests an evolutionary signal in which western Tethys acted as a centre of origination. Diversity at a single location is constrained ecologically and diversification is controlled by migration into new realms. Recorded diversity and available area of outcrop seem to be correlated, but alternative interpretations can be drawn, including large-scale bias in the fossil record or operation of similar causes (e.g., effect of sea-level fluctuation). Comparing recorded diversity with separate factors independently leads to conflicting results. A multivariate approach suggests that the main trend in recorded diversity might be partially related to evolutionary signal or biases connected with the heterogeneity of the fossil record. Results from other approaches (phylogeny, morphological disparity) are consistent with and emphasise the evolutionary significance of the recorded diversity of spatangoids.     

Decapod Crustacea from the Agrio Formation (Lower Cretaceous) of the Neuquén Basin,Argentina

Abstract: Two species of decapod crustacean are recorded from the Agua de la Mula Member of the Agrio Formation (Upper Hauterivian – Lower Barremian) of the Neuquén Basin of west‐central Argentina, namely Astacodes falcifer Bell and a new species of Palaeohomarus, P. pacificus. The preservation of the specimens is exceptional, some showing delicate compound eyes and a stridulatory apparatus, features rarely found in fossil forms. Many specimens are preserved articulated inside calcareous nodules, within dark‐grey shales. The lobster‐bearing sediments accumulated in a low‐energy marine environment and diagenetic mineralization occurred very rapidly, prior to significant decay, thus allowing exceptional preservation of specimens. Palaeohomarus was a rare genus in the Cretaceous with a palaeogeographic distribution restricted to the Mediterranean Tethys, the eastern USA and Madagascar, while Astacodes falcifer has been recorded only from Speeton (eastern England) and Neuquén.     

Correct author citation of the Late Devonian plant <Emphasis Type="Italic">Archaeopteris</Emphasis> (Progymnospermopsida)

Archaeopteris as a representative fossil plant genus in the class Progymnospermopsida has been extensively recorded in the Late Devonian of the world. Although its phylogenetic, paleoecological, and biostratigraphic significances are well known, the author citation of the generic name Archaeopteris remains problematic. Here, it is shown that Dionys Stur was the first to treat Archaeopteris as an independent genus.Therefore, the generic name should be cited as Archaeopteris (Dawson) Stur, while Archaeopteris Dawson and Archaeopteris (Dawson) Lesquereux are incorrect.     

Fossilization processes of graptolites: insights from the experimental decay of Rhabdopleura sp. (Pterobranchia)

Laboratory experiments documenting the decomposition pattern of extant organisms are used to reconstruct the anatomy and taphonomy of fossil taxa. The subclass Graptolithina (Hemichordata: Pterobranchia) is a significant fossil taxon of the Palaeozoic era, represented by just one modern genus, Rhabdopleura. The rich graptolite fossil record is characterized by an almost total absence of fossil zooids. Here we investigated the temporal decay pattern of Rhabdopleura sp. tubes, stolons and single zooids removed from the tubarium. Tubes showed decay after four days, when fuselli began to separate from the tube walls. This rapid loss may explain the absence of fuselli from some graptolite fossils. The black stolon did not show decay until day 155. One day after their removal, zooids quickly decomposed in the following temporal sequence: (1) tentacles; (2) ectoderm; (3) arms; (4) gut; (5) cephalic shield, leading to complete disappearance of recognizable body parts in the majority of experimental zooids within 64–104 h. The most resistant zooid features to decay (61 days) were black‐pigmented granules. These results indicate that tubes and the black stolon would persist for weeks across death, transport and burial, whereas a complete decay of zooid features occurs in few days, providing an explanation for the overall poor record of fossil graptolite zooids and suggesting that recorded silhouettes of fossil zooids may be attributed to fossil decay‐resistant pigments.