Triuridaceae fossil flowers from the Upper Cretaceous of New Jersey

We report here on a series of fossil flowers exhibiting a mosaic of characters present in the extant monocot family Triuridaceae. Phylogenetic analyses of morphological data from a broad sample of extant monocots confirm the affinities of the fossils with modern Triuridaceae. The fossil flowers were collected from outcrops of the Raritan Formation (Upper Cretaceous, ～90 million years before present), New Jersey, USA. These are the oldest known unequivocal monocot flowers. Because other reports of earliest monocots are all based on equivocal character suites and/or ambiguously preserved fossil material, the Triuridaceae fossils reported here should also be considered as the oldest unequivocal fossil monocots. Flowers are minute and unisexual (only male flowers are known); the perianth is composed of six tepals, lacking stomata. The unicyclic androecium is of three stamens with dithecal, monosporangiate, extrorse anthers that open by longitudinal slits. The endothecium has U-shaped type thickenings. Pollen grains are monosulcate. The triurid fossil flowers can be separated into three distinctive species. On the basis of phylogenetic analyses of morphological characters, the fossil taxa nest within the completely saprophytic achlorophyllous Triuridaceae supporting the interpretation that the extinct plants were also achlorophyllous and saprophytic. If so, this represents the earliest known fossil occurrence of the saprophytic/mycotrophic habit in angiosperms.     

Two new fossil flowers of magnoliid affinity from the Late Cretaceous of New Jersey

Two taxa of cupulate magnoliid fossil flowers, Cronquistiflora and Detrusandra, are described from the Late Cretaceous (Turonian, ∼90 million years before present [MYBP]) Raritan (or lower Magothy) Formation of New Jersey. The fossil taxa are represented by flowers at various stages of development, associated fragments of cup-shaped floral receptacles with attached anthers, and isolated anthers. Both taxa have laminar stamens with adaxial thecae and valvate dehiscence. Pollen is boat-shaped and foveolate in anthers associated with Cronquistiflora and spherical with reticulate ornamentation in Detrusandra. Cup-shaped receptacles are externally bracteose in both taxa. The receptacle of Cronquistiflora is broader than the campanulate one of Detrusandra. Cronquistiflora also has more carpels (∼50 in a spiral vs. ∼5 in a whorl or tight spiral). In Detrusandra the carpels are surrounded by dorsiventrally flattened structures (pistillodes?) that are remote from the attachment of the stamens near the distal rim of the receptacular cupule. Detrusandra stigmas are rounded and bilobed, while those of Cronquistiflora, although bilateral in symmetry, are somewhat peltate. The fossil taxa share prominent characters with extant cupulate magnoliids (e.g., Eupomatia, Calycanthus), but also share characters with other magnoliids including Winteraceae. These fossils represent taxa that are character mosaics relative to currently recognized families. Inclusion of these fossils in existing data matrices and ensuing phylogenetic analyses effect changes in tree topologies consistent with their mosaicism relative to modern taxa. But such analyses do not definitively demonstrate the affinities of the fossils other than illustrating that these fossils are generalized magnoliids. Additional analysis of modern and fossil magnoliids is necessary to fully appreciate the phylogenetic significance and positions of these fossil taxa. However, the results of the phylogenetic analyses do introduce the possibility that extinct taxa of Magnoliales with cupulate floral receptacles were transitional between basal angiosperms and those with tricolpate pollen. The fossils provide insights into the timing of evolution of character complexes now associated with coleopteran pollination.     

Diversity in obscurity: fossil flowers and the early history of angiosperms

In the second half of the nineteenth century, pioneering discoveries of rich assemblages of fossil plants from the Cretaceous resulted in considerable interest in the first appearance of angiosperms in the geological record. Darwin''s famous comment, which labelled the ‘rapid development’ of angiosperms an ‘abominable mystery’, dates from this time. Darwin and his contemporaries were puzzled by the relatively late, seemingly sudden and geographically widespread appearance of modern-looking angiosperms in Late Cretaceous floras. Today, the early diversification of angiosperms seems much less ‘rapid’. Angiosperms were clearly present in the Early Cretaceous, 20–30 Myr before they attained the level of ecological dominance reflected in some mid-Cretaceous floras, and angiosperm leaves and pollen show a distinct pattern of steadily increasing diversity and complexity through this interval. Early angiosperm fossil flowers show a similar orderly diversification and also provide detailed insights into the changing reproductive biology and phylogenetic diversity of angiosperms from the Early Cretaceous. In addition, newly discovered fossil flowers indicate considerable, previously unrecognized, cryptic diversity among the earliest angiosperms known from the fossil record. Lineages that today have an herbaceous or shrubby habit were well represented. Monocotyledons, which have previously been difficult to recognize among assemblages of early fossil angiosperms, were also diverse and prominent in many Early Cretaceous ecosystems.     

Mid-Cretaceous charred fossil flowers reveal direct observation of arthropod feeding strategies

Although plant-arthropod relationships underpin the dramatic rise in diversity and ecological dominance of flowering plants and their associated arthropods, direct observations of such interactions in the fossil record are rare, as these ephemeral moments are difficult to preserve. Three-dimensionally preserved charred remains of Chloranthistemon flowers from the Late Albian to Early Cenomanian of Germany preserve scales of mosquitoes and an oribatid mite with mouthparts inserted into the pollen sac. Mosquitoes, which today are frequent nectar feeders, and the mite were feeding on pollen at the time wildfire consumed the flowers. These findings document directly arthropod feeding strategies and their role in decomposition.     

Carbon isotope composition of fossil charcoal reveals aridity changes in the NW Mediterranean Basin

Although several proxies for the inference of precipitation have been proposed, evidence of changes in aridity during the Holocene is scarce, and most is only qualitative. Moreover, precipitation regimes show relatively poor spatial correlations and can exhibit contrasting responses to global climate trends in different areas. Thus, there is a need to concentrate efforts at the local scale in order to increase the spatial resolution of palaeoclimate records, especially regarding water availability in semiarid zones. We propose the analysis of carbon isotope composition (δ¹³C) in fossil charcoal (routinely recovered from archaeological sites) to quantify changes in water availability in the past. We applied this approach to reconstruct variations in aridity during the last four millennia in the Ebro Depression (NE Iberian Peninsula). First, we studied the effect of carbonization over a range of temperatures (300–500°C) on the δ¹³C of Aleppo pine (Pinus halepensis Mill.) wood cores, collected from nine locations in NE Iberian Peninsula with distinct water availability. Despite significant changes in δ¹³C caused by carbonization, the original climatic signal of wood δ¹³C was well preserved. Moreover, δ¹³C shifts induced by this process were successfully corrected by accounting for variation in charcoal carbon concentration (%C). After removing the effect of carbonization, we estimated annual precipitation (P) and the ratio between annual precipitation and evapotranspiration (P/E) from the δ¹³C of fossil charcoal. In general, estimated water availability in the past was higher than present values, indicating that latter‐day (semiarid) conditions are mostly due to recent climate changes. The good agreement between our findings and other evidence indicates that the analysis of δ¹³C in charcoal may be useful to expand current palaeoclimate records as it provides a complementary (and quantitative) source of information to assess climate dynamics.     

Functional reconstruction of the supralaryngeal vocal tract of fossil human

The purpose of the study was to reconstruct the supralaryngeal vocal tract of the archaic human from Petralona in Greece and to assess its vocal abilities. The reconstruction of the position of the hyoid bone of the Palaeolithic hominid from Petralona has been done by using the relation between the flexion of the basicranium and the inclination of the processus styloideus. The results indicate the lower position of the larynx in the fossil hominid. This conclusion was confirmed by an assessment of the position of the hyoid bones by extrapolating from a sample of 45 x-rays scans of recent adult human males.     

Two early eudicot fossil flowers from the Kamikitaba assemblage (Coniacian,Late Cretaceous) in northeastern Japan

Two new fossil taxa referable to the basal eudicot grade are described from the Kamikitaba locality (ca. 89 MYBP, early Coniacian: Late Cretaceous) of the Futaba Group in Japan. These charcoalified mesofossils exhibit well-preserved three-dimensional structure and were analyzed using synchrotron-radiation X-ray microtomography to document their composition and internal structure. Cathiaria japonica sp. nov. is represented by infructescence segments that consist of an axis bearing three to four fruits. The capsular fruits are sessile and dehiscent and consist of a gynoecium subtended by a bract. No perianth parts are present. The gynoecium is monocarpellate containing two pendulous seeds. The carpel is ascidiate in the lower half and conduplicate in the upper part, and the style is deflected abaxially with a large, obliquely decurrent stigma. Pollen grains are tricolpate with a reticulate exine. The morphological features of Cathiaria are consistent with an assignment to the Buxaceae s. l. (including Didymelaceae). Archaestella verticillatus gen. et sp. nov. is represented by flowers that are small, actinomorphic, pedicellate, bisexual, semi-inferior, and multicarpellate. The floral receptacle is cup shaped with a perigynous perianth consisting of several tepals inserted around the rim. The gynoecium consists of a whorl of ten conduplicate, laterally connate but distally distinct carpels with a conspicuous dorsal bulge, including a central cavity. The styles are short, becoming recurved with a ventrally decurrent stigma. Seeds are ca. 10 per carpel, marginal, pendulous from the broad, oblique summit of the locule. Pollen grains are tricolpate with a reticulate exine pattern, suggesting a relationship to eudicots. The morphological features of Archaestella indicate a possible relationship to Trochodendraceae in the basal grade of eudicots. The fossil currently provides the earliest record of the family and documents the presence of Trochodendraceae in eastern Eurasia during the middle part of the Late Cretaceous.     

The representation of rainfall and fire intensity in fossil pollen and charcoal records from a South African savanna

Savanna ecosystems of southern Africa are strongly influenced by water availability and fire intensity, and this study aimed to show whether these two specific environmental variables are reflected in fossil pollen and charcoal records. Palaeoecological records of charcoal concentration from three short sedimentary sequences were used to reconstruct fire intensity (the rate of energy released along a fire front) over 50 yrs in the Kruger National Park (KNP), South Africa. Fossil pollen percentages from surface and core-sediment samples taken from water bodies were compared with the reconstructed fire intensity over space and time. Higher fire intensity led to increased herbaceous cover and decreased woody plant growth. Fossil pollen percentages and charcoal concentrations were also compared with rainfall records. Increased macroscopic charcoal abundances and percentages of Cyperaceae pollen corresponded to periods of increased rainfall. The results of this study have shown that fossil pollen and charcoal records from savanna environments can be used to reconstruct past fire intensity and its impact on terrestrial vegetation, as well as changes in rainfall.     

三维技术在古昆虫复原图制作中的应用

本文简单介绍了Autodesk Maya等软件以及利用三维技术制作古昆虫复原图所涉及到的三大方面知识,包括:三维昆虫制作、场景设计和艺术气氛。较为详细的介绍了利用三维软件制作昆虫的主要步骤。总结了在制作复原图时,将生物学、计算机技术、美术学三方面知识相结合的经验和技巧。为三维技术在古昆虫学研究工作中的推广和使用提供了更多思路。     

Observations and comments on the reliability of muscle reconstruction in fossil vertebrates

In Canis and Ursus the largest proportion of attachments of muscles of the shoulder and brachium on the scapula and humerus is direct; fewer attachments are aponeurotic or tendinous. In both genera most attachments can be associated with superficial osteological features (scars or delimitable surfaces); attachments that lack such features are direct. Most aponeurotic attachments are associated with rugose scarring whereas tendinous attachments are often associated with smooth surfaces. Although most attachments can be associated with osteological features the areal extent of attachment is often not inferrable from the bone. The inference of muscle size or functional significance from osteological features is problematic. The amount of myological information that can be deciphered from the osteology in Canis and Ursus is greater than that reported for particular members of other vertebrate groups which suggests that there may be differences in the degree to which muscles can be reconstructed from superficial osteology alone. Nonetheless, even in mammals such as the Carnivora, detailed muscular reconstructions in extinct taxa cannot be achieved without reference to the musculature of extant relatives. Such reconstructions rely on assumptions, that often have not been adequately tested, regarding the similarity of musculature in closely related taxa. This testing and well corroborated hypotheses of phylogenetic relationship are essential for the evaluation of the accuracy of reconstructions of the musculature in fossil vertebrates.     

Triacylated cyanidin 3-(3X-glucosylsambubioside)-5-glucosides from the flowers of Malcolmia maritima

Three acylated cyanidin 3-(3(X)-glucosylsambubioside)-5-glucosides (1-3) and one non-acylated cyanidin 3-(3(X)-glucosylsambubioside)-5-glucoside (4) were isolated from the purple-violet or violet flowers and purple stems of Malcolmia maritima (L.) R. Br (the Cruciferae), and their structures were determined by chemical and spectroscopic methods. In the flowers of this plant, pigment 1 was determined to be cyanidin 3-O-[2-O-(2-O-(trans-sinapoyl)-3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-6-O-(trans-p-coumaroyl)-beta-D-glucopyranoside]-5-O-[6-O-(malonyl)-(beta-D-glucopyranoside) as a major pigment, and a minor pigment 2 was determined to be the cis-p-coumaroyl isomer of pigment 1. In the stems, pigment 3 was determined to be cyanidin 3-O-[2-O-(2-O-(trans-sinapoyl)-3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-6-O-(trans-p-coumaroyl)-beta-d-glucopyranoside]-5-O-(beta-D-glucopyranoside) as a major anthocyanin, and also a non-acylated anthocyanin, cyanidin 3-O-[2-O-(3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside) was determined to be a minor pigment (pigment 4). In this study, it was established that the acylation-enzymes of malonic acid has important roles for the acylation of 5-glucose residues of these anthocyanins in the flower-tissues of M. maritima; however, the similar enzymatic reactions seemed to be inhibited or lacking in the stem-tissues.     

Ecdysteroids from the flowers of Aerva javanica

Four new ecdysteroids (1–4), along with three known steroids, β-ecdysone (5), 5-β-2-deoxyintegristerone A (6) and 24-epi-makisterone A (7) (Fig. 1), were isolated from the methanolic extract of the flowers of Aerva javanica by using normal and reverse phase chromatography. The structures of the new compounds (1–4) were determined due to 1D (¹H and ¹³C), 2D NMR (HSQC, HMBC, COSY, NOESY) techniques and high resolution mass spectrometry (HREIMS). The known compounds (5–7) were characterized based on the 1D NMR spectroscopy and mass spectrometry and by comparison with the literature values. All isolates were evaluated for their inhibitory activities against enzymes acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase (LOX).     

Pseudoguaianolides from the flowers of Parthenium hysterophorus

Chemical investigation on the flowers of Parthenium hysterophorus has resulted in the isolation of four new pseudoguaianolides, hysterones A-D along with the known compounds, parthenin, coronopilin, 2beta-hydroxycoronopilin and tetraneurin-A. The structures of the new compounds were established by interpretation of their spectral (1D and 2D NMR) data. The X-ray crystallographic analysis of hysterones A and C was also carried out.     

Anthocyanidin glycosides from the flowers of Alstroemeria

Three anthocyanins were isolated from the red flowers of four cultivars of Alstroemeria. Two compounds were novel anthocyanidin glycosides; the 3-rutinoside and 3-monoglucoside of 6-hydroxycyanidin. Cyanidin 3-rutinoside was also present in the petals.     

Alkaloids from the flowers of Erythrina americana

The two alkaloids, α- and β-erythroidine have been identified in 0.034 and 0.11 % yield in flowers of Erythrina americana and could be responsible for the hypnotic activity of flower extracts.     

Hydrostatics of fossil ectocochleate cephalopods and its significance for the reconstruction of their lifestyle

The importance of hydrostatics for ectocochleate cephalopods and for the reconstruction of their lifestyle as well as the implications of hydrostatics and further physical conditions for the ontogenetic shell formation process are discussed. The method used by some authors of merely assuming neutral buoyancy is criticized as not allowable, since even in case of the theoretically possible condition of neutral buoyancy the obligatory vertical shell orientation in orthoconic forms would definitely preclude a horizontal swimming capability. The often presumed neutral buoyancy follows from an old misunderstanding with regard to the original function of the phragmocone, which was modified and amplified only in the course of evolution. The idea of a benthic lifestyle of fossil ectocochleate cephalopods in a gastropod-like fashion is maintained and extended to further palaeozoic forms.