Volker Wilde

Phylogeny of Nymphaea (Nymphaeaceae): Evidence from Substitutions and Microstructural Changes in the Chloroplast trnT‐trnF Region

Nymphaea is the most speciose, phenotypically diverse, and geographically widespread (nearly global) genus of Nymphaeales. Phylogenetic relationships among 35 of an estimated 45–50 species of Nymphaea are presented based on an analysis of the chloroplast trnT‐trnF region. Because this is the first phylogenetic analysis of Nymphaea, monophyly of the genus had to be tested, and its status in Nymphaeales had to be inferred. Rooting was therefore extended to more distant outgroups (Amborella, Austrobaileyales). Monophyly of Nymphaea received weak support, with a Euryale‐Victoria clade appearing as sister. The three major lineages within Nymphaea are constituted by the northern temperate subg. Nymphaea that is sister to all remaining species, a subgg. Hydrocallis‐Lotos clade, and a subgg. Anecphya‐Brachyceras clade. The Australian genus Ondinea was nested at species level within Nymphaea subg. Anecphya. The pantropical subg. Brachyceras as currently circumscribed does not appear natural, with Nymphaea petersiana belonging to subg. Lotos. Microstructural changes are frequent and highly informative, exhibiting lower levels of homoplasy than substitutions. Reconstructing the evolution of microstructural changes shows a strong insertion bias in simple sequence repeats. Complex indels are often explained by mutational events that occurred independently in different parts of the tree rather than being the result of stepwise events at subsequent nodes. AT‐rich, satellite‐like sequence parts have evolved independently in the P8 stem loop of the trnL group I intron in Nuphar and in major lineages of Nymphaea. They seem to be conserved in sequence within species but are highly variable among species. Moreover, the trnT‐trnF region provides a signal that allows recognition (bar coding) of most species analyzed so far.

Terpenoid composition of three fossil resins from Cretaceous and Tertiary conifers

The terpenoid composition of three fossil resins from macrofossils of Cretaceous and Tertiary conifers has been analyzed by gas chromatography–mass spectrometry (GC–MS). The mono-, sesqui- and diterpenoids which have been identified in the resin extracts are derived from precursors produced by the respective source plants and may be used as chemosystematic markers when compared with terpenoids in extant conifers. Sesquiterpenoids (cedrene, cuparene, cadinanes) and phenolic diterpenoids (ferruginol and derivatives) are the major components in Cupressospermum saxonicum Mai (Miocene). The terpenoid characteristics strongly support a relationship to the Cupressaceae s. str. The resin of Doliostrobus taxiformis (Sternberg) Kvacek (Eocene) consists of abietane and pimarane type resin acids accompanied by minor amounts of phenolic diterpenoids (ferruginol, hinokiol). According to morphological and anatomical characteristics, D. taxiformis was previously compared to both, extant Araucariaceae and Cupressaceae s.l., but the terpenoid pattern of the resin now supports a relationship to the Cupressaceae s.l. rather than to Araucariaceae. Degraded diterpenoids of the abietane type are the major compounds in the extract of Tritaenia linkii (Roemer) Magdefrau et Rudolf (Lower Cretaceous) indicating considerable oxidative alteration of the resin. Since the terpenoids in the resin of T. linkii are highly degraded or belong to the common abietane class, the leaves cannot be assigned or compared to any modern family based on their terpenoid composition. The presence of ferruginol probably excludes pinaceous affinities. Terpenoids proved to be valuable chemosystematic markers for fossil conifers once they are adequately preserved. The analysis of resin extracts by GC–MS is a suitable tool for the investigation of soluble compounds in fossil plants.

Paleoenvironment of an Early Devonian Land–Sea Transition: a Case Study from the Southern Margin of the Old Red Continent (Mosel Valley, Germany)

Abstract An interdisciplinary approach was used to investigate the facies and paleogeography of the Lower Devonian sedimentary sequence of the Alken quarry, Mosel Valley, Germany. This 87-m-thick sequence consists of stratified sandstones and sandy shales of the Nellenköpfchen Formation (uppermost Lower Emsian). Previous interpretations of the depositional environment include terrestrial, deltaic, and shallow-marine settings. Two distinct fossiliferous units contain abundant terrestrial plant remains and a diverse mixed terrestrial to marine fauna. Physical sedimentary structures are common throughout, whereas bioturbation is restricted mostly to the fossiliferous intervals. Erosional surfaces frequently separate the beds. Aside from ripple cross-stratification and parallel bedding, longitudinal inclined stratification is most common. Channel-fill structures are less frequent. Scour-and-fill structures exhibit marked disconformities of irregular shape on a smaller scale (dm). Mud-pebble lags at the base of laterally prograding cross-bedded layers, scour-and-fill structures, and drainage rills characterize the upper part of the section. Desiccation cracks, wind-induced striation, and water-level marks occur more sporadically in the exposure. The sedimentary structures and the paleontological information indicate a marine to brackish depositional environment that frequently was emergent. The presence of conspicuous channel-related structures reflects intertidal conditions along the coastal region of a presumed Hunsrück Island/Archipelago. Lagoons and estuaries were bordered by extended tidal flats, in which migrating channels frequently occurred. Terrestrial plant remains, however, indicate a position at the land/sea interface, which was characterized by a complex configuration of different environments. The accumulation of concentrated plant material may have been related to distinct meteorological events such as hurricanes.

Fossil Leaves of the Araceae from the European Eocene and Notes on Other Aroid Fossils

A comparative study of leaf morphology and venation patterns of extant Araceae has been undertaken in order to define groups matching aroid fossil leaves from the Eocene of Central Europe. As a result, four morphogenera have been recognized: Araceophyllum Kräusel emend. Wilde, Z. Kvaček & Bogner (subfamily Pothoideae); Araciphyllites Wilde, Z. Kvaček & Bogner, gen. nov. (subfamilies Monsteroideae and Aroideae); Caladiosoma Berry (tribes Colocasieae and Caladieae); and Nitophyllites Iljinskaja emend. Fedotov (tribes Peltandreae and Arophyteae). The leaf fossils studied from the Eocene sites at Messel and Eckfeld (Germany) and Kučlín (Czech Republic) have been included in four species: Araciphyllites tertiarius (Engelhardt) Wilde, Z. Kvaček & Bogner, comb. nov. (common at Messel, rare at Eckfeld); Araciphyllites schaarschmidtii Wilde, Z. Kvaček & Bogner, sp. nov. (a single specimen at Messel); Caladiosoma messelense Wilde, Z. Kvaček & Bogner, sp. nov. (rare at Messel); and Nitophyllites bohemicus Wilde, Z. Kvaček & Bogner, sp. nov. (a single fragment at Kučlín). Outside Europe, other Tertiary aroid foliage species that we have revised nomenclaturally include Araciphyllites tobleri (Kräusel) Wilde, Z. Kvaček & Bogner, comb. nov. (Neogene of Sumatra), and Nitophyllites limnestis (Dilcher & Daghlian) Wilde, Z. Kvaček & Bogner, comb. nov. (Eocene of the Claiborne Formation, Tennessee). Critical notes are also provided concerning other Cenozoic records of Araceae and their affinities, like Nitophyllites zaisanicus Iljinskaja emend. Fedotov (late Paleocene‐Eocene of Kazakhstan and the Russian Far East) and Peltandra primaeva Hickey (Eocene of the Golden Valley Formation, North Dakota). The mentioned four species of aroid foliage add considerably to the reliable fossil record of the family that now contains ca. 10 species based on leaves. Their nearest living relatives suggest a (para)tropical to subtropical climate that is well in accordance with the paleogeographic position and the accompanying floras of the respective localities. Except for the two species of Araciphyllites from Messel, they all obviously represent helophytes of aquatic/hemiaquatic or muddy/swampy sites. Except for Caladiosoma miocenicum, which is suggested to be of Neogene age, all of the fossil leaves of Araceae are mostly of Eocene age, suggesting a considerable diversity of Araceae as early as in the early Paleogene. We caution against taking for granted all fossil records whose names imply affinities with the Araceae. Many of them are excluded from the family or are at least doubtful. Others, mainly based on reproductive structures or whole plants, contribute important information for understanding of the fossil history of aroids.

Testing for the effects and consequences of mid paleogene climate change on insect herbivory.

Background The Eocene, a time of fluctuating environmental change and biome evolution, was generally driven by exceptionally warm temperatures. The Messel (47.8 Ma) and Eckfeld (44.3 Ma) deposits offer a rare opportunity to take a census of two, deep-time ecosystems occurring during a greenhouse system. An understanding of the long-term consequences of extreme warming and cooling events during this interval, particularly on angiosperms and insects that dominate terrestrial biodiversity, can provide insights into the biotic consequences of current global climatic warming. Methodology/Principal Findings We compare insect-feeding damage within two middle Eocene fossil floras, Messel and Eckfeld, in Germany. From these small lake deposits, we studied 16,082 angiosperm leaves and scored each specimen for the presence or absence of 89 distinctive and diagnosable insect damage types (DTs), each of which was allocated to a major functional feeding group, including four varieties of external foliage feeding, piercing- and-sucking, leaf mining, galling, seed predation, and oviposition. Methods used for treatment of presence–absence data included general linear models and standard univariate, bivariate and multivariate statistical techniques. Conclusions/Significance Our results show an unexpectedly high diversity and level of insect feeding than comparable, penecontemporaneous floras from North and South America. In addition, we found a higher level of herbivory on evergreen, rather than deciduous taxa at Messel. This pattern is explained by a ca. 2.5-fold increase in atmospheric CO2 that overwhelmed evergreen antiherbivore defenses, subsequently lessened during the more ameliorated levels of Eckfeld times. These patterns reveal important, previously undocumented features of plant-host and insect-herbivore diversification during the European mid Eocene.

A 600 k.y. record of El Niño–Southern Oscillation (ENSO): Evidence for persisting teleconnections during the Middle Eocene greenhouse climate of Central Europe

The El Nino–Southern Oscillation (ENSO) is a globally important factor in today’s climate dynamics. Annually laminated oil shales from the maar lake of Messel (Germany) provide high-resolution sedimentological and paleoenvironmental data of a time interval of ~600 k.y. during the Eocene greenhouse phase. Individual laminae consist of a light spring and summer algal layer (Tetraedron minimum layer) and a dark winter layer composed of terrigenous background sediment. Four sections were selected from the core of the Messel 2001 well in order to count varves and to measure total varve thickness and the thickness of light and dark laminae. Spectral analyses were done in order to detect possible cyclic fl uctuations in varve thickness. Fluctuations are signifi cant in the quasi-biennial (2.1–2.5 yr) and low-frequency band (2.8–3.5 yr, 4.9–5.6 yr), thus showing that algal growth as well as the background sedimentation were controlled by ENSO effects at least over a time interval of 600 k.y. This confirms the existence of a previously postulated robust Eocene ENSO. Significant peaks within a quasi-decadal (10–11 yr), interdecadal (17–26 yr), and multidecadal band (~52 yr, ~82 yr) show either the enduring influence of more or less cyclic instabilities or the influence of solar cycles.

Novel phenolic biomarker triterpenoids of fossil laticifers in Eocene brown coal from Geiseltal, Germany

Abstract Novel phenolic triterpenoids were tentatively identified with known mono-, tri- and tetraaromatic oleanane, ursane, and lupane hydrocarbons and natural product precursors (α-amyrone, α-amyrin) in the extract of Eocene fossil laticifers called “Affenhaar” from the Geiseltal lignites, Germany. The novel phenolic terpenoids are mono- and triaromatic hydroxytriterpenoids (OH at position 1, 2 or 3) of the oleanane, ursane, and lupane classes: hydroxy-24,25-dinoroleana-1,3,5(10),12-tetraene, hydroxy-24,25-dinorlupa-1,3,5(10)-triene, hydroxy-24,25-dinorlupa-1,3,5(10),19(22)-tetraene, hydroxy-24,25,26,27-tetranorursa-1,3,5,7,9,11,13-heptaene, hydroxy-24,25,26,27-tetranoroleana-1,3,5,7,9,11,13-heptaene, and hydroxy-24,25,26,27-tetranorlupa-1,3,5,7,9,11,13-heptaene. The structures of the novel compounds were proposed based on the interpretation of the gas chromatography–mass spectrometry data of the underivatized and silylated total extract.

Fossil Cashew Nuts from the Eocene of Europe: Biogeographic Links between Africa and South America

Cashew nuts have been identified among compression fossils from the early Middle Eocene lake sediments of Messel, Germany. These fossil fruits confirm that the cashew genus, Anacardium, was formerly distributed in Europe, remote from the modern native distribution in Central and South America. Anacardium germanicum sp. n. shows that the characteristic inflated pedicel, or “cashew apple,” which facilitates biotic dispersal of cashew nuts, evolved at least 47 million yr ago. It was previously proposed that Anacardium and its African sister genus, Fegimanra, diverged from their common ancestor when the landmasses of Africa and South America separated. However, the paleobotanical data indicate a connection via the Northern Hemisphere with Europe as an important footstep in the spread of this clade between Africa and the New World. The former North Atlantic landbridge connecting North America and Europe via Greenland is implicated in the phytogeographic spread of Anacardium during the Early and Middle Eocene.

Eocene fossil is earliest evidence of flower-visiting by birds

Birds are important pollinators, but the evolutionary history of ornithophily (bird pollination) is poorly known. Here, we report a skeleton of the avian taxon Pumiliornis from the middle Eocene of Messel in Germany with preserved stomach contents containing numerous pollen grains of an eudicotyledonous angiosperm. The skeletal morphology of Pumiliornis is in agreement with this bird having been a, presumably nectarivorous, flower-visitor. It represents the earliest and first direct fossil evidence of flower-visiting by birds and indicates a minimum age of 47 million years for the origin of bird–flower interactions. As Pumiliornis does not belong to any of the modern groups of flower-visiting birds, the origin of ornithophily in some angiosperm lineages may have predated that of their extant avian pollinators.

The value of X-ray approaches in the study of the Messel fruit and seed flora

X-ray tomographic methods have been evaluated for their suitability to visualise morphology and anatomy of fossil fruits and seeds preserved in the oil shale of the Middle Eocene Messel Formation (former Lake Messel, near Darmstadt, Germany). Micro-computed tomography (microCT) is suitable for evaluation of gross morphology and tissue preservation. Synchrotron radiation X-ray tomographic microscopy (SRXTM) enables visualisation of gross morphology, tissues, and their detailed cellular structure. Of 30 taxa studied, only 4 exhibit good cellular detail. The reason for lack of detail in other taxa is unclear but may be related to subtle variations in chemical composition or physical structure of their tissues. X-ray tomographic data also permit structures, such as locule casts, to be visualised, giving additional features for comparison with other extinct and extant taxa. X-ray tomography has revealed important features of Messel specimens, which have (1) provided key taxonomic characters and supported recognition of new taxa, some of which are the earliest fossil representatives of modern genera (Pleiogynium, Anacardiaceae; Berchemia, Rhamnaceae), (2) demonstrated the absence of modifications for epizoochory in this flora, and (3) revealed aspects of exceptional preservation relevant to mammal and bird diet (e.g. soft tissue in fruits of Vitaceae).