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) Kva ek (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) Mägdefrau 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.     

Eubrachythoracid arthrodires from Gogo, Western Australia

Two monotypic genera of coccosteoid eubrachythoracid arthrodires are described from the Upper Devonian Gogo Formation of Western Australia as Compagopiscis gen. nov. and Gogopiscis gen. nov. They are most closely related to Torosteus Gardiner & Miles, also from the Gogo Formation, and all three are placed in the family Plourdosteidae Vezina, 1990; Compagopiscis and Gogopiscis are jointly the sister-group of Torosteus.     

Organogenesis in vitro of tissues from mature conifers

Summary Shoot and embryolike structures were obtained in cultures of various tissues of mature conifer trees. Morphogenesis occurred in haploid and diploid tissues of female cones ofPinus mugo andPicea abies, although only rarely. Vegetative shoots dissected from early spring buds ofAbies balsamea, Picea glauca, andPseudotsuga menziesii were more responsive, with most of the organized growth occurring at the base of young needles. The following sequence of treatments was most effective: (a) collect twigs with buds shortly before budbreak, (b) cold store for at least 1 month, (c) force buds to break before excision of the vegetative shoots (keep submerged in water during excision), and (d) soak explant in malonic acid, 1 g/l, for 15 min before transfer of the shoots to the nutrient medium.     

中国松杉类植物濒危等级划分的比较

本文根据世界保护监测中心(WCMC)和国际松杉类植物专家(CSG)编制的濒危植物名录,以及中国植物红皮书(第1卷)列出中国受威胁松杉类植物共141种及变种。通过对上述三者濒危等级的比较表明,它们在中国松杉类植物濒危等级的划分上并不完全一致,主要原因是划分物种濒危等级的标准不同或资料依据不完全等。最后,作者根据1994年IUCN提出的物种受威胁等级划分标准草案(2.3版本),对中国松杉类一些濒危种类的等级划分作了初步分析和讨论。     

Two species of Haskinsia Grierson & Banks (Lycopsida) from the Middle Devonian of Xinjiang,China, and consideration of their palaeogeographical significance

Two species of the Devonian herbaceous lycopsid Haskinsia Grierson & Banks, H. hastata Berry & Edwards and H. sagittata Edwards & Benedetto, are reported from the Hujiersite Formation (Givetian–Middle Devonian), Xinjiang, north‐west China. Both species were first described from Venezuela. Haskinsia hastata from Xinjiang has hastate leaves with toothed margins, and a pair of basal narrow lateral segments which curve distally. It is assigned to a new subspecies because of the toothed margins which cannot be demonstrated in Venezuelan material. The scar of the sporangium stalk is observed for the first time in specimens of H. sagittata, on the leaves of which a possible ligule structure is also shown. On the basis of our observations on both Xinjiang and Venezuelan specimens, the diagnosis of Haskinsia is enlarged to accommodate plants whose lamina has entire or toothed margins. The palaeophytogeography of the genus, otherwise known from South and North America, is discussed. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 633–644.     

An extraordinary new rheophyte in the genus Leptactina (Rubiaceae, Pavetteae) from Rio Muni (Equatorial Guinea)

A distinctive new species of Rubiaceae from Rio Muni, Equatorial Guinea, is described and illustrated. Leptactina rheophytica is the only rheophyte known in the genus. Its diagnostic characters are elucidated, its taxonomic affinities are discussed, and notes on its conservation status are provided.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 109–113.     

亚洲大陆植物志中的针叶树评述

以比较清楚的针叶树类为例,同时参考世界性的专著,对亚洲大陆各地的植物志进行了系统的比较研究,发现尽管亚洲大陆的经典植物分类已经进行了三百多年的长期而且广泛的研究,仍然有很长的路要走,特别是经典分类受到严重挑战的今天。     

Margin feeding damage on the leaves of conifers and ginkgoales from the Mesozoic of Transbaikalia

A new approach to the formal classification of arthropod margin feeding plant damage is proposed. Several types of margin feeding traces on the leaves of Pityophyllum sp. and Ginkgoites sp. from the Upper Jurassic-Lower Cretaceous Chernovskie Kopi locality, Transbaikalia, are described as five new species in the genus Pinovulnus gen. nov.     

Two new species of Vellozia (Velloziaceae) from Minas Gerais, Brazil

Two new species of Vellozia from the Espinhaco range in the State of Minas Gerais, Brazil, are described and their taxonomic relationships are considered. A discussion of their geographical distribution and an account of their leaf anatomy is provided.     

Mummified fossil of Keteleeria from the Late Pleistocene of Maoming Basin,South China,and its phytogeographical and paleoecological implications

Keteleeria is a small genus of Pinaceae now mainly restricted to eastern Asia. Although this genus has been documented with a wide distribution in the geologic record of Europe, North America, and Asia, its history in low‐latitude areas (including South China) has remained obscure. In this paper, a fossil wood of Keteleeria sp. is described from the Late Pleistocene (29–27 ka BP) of the Maoming Basin, South China. This wood is the most ancient megafossil evidence of Keteleeria within the modern distribution area of this genus. The fossil records of Keteleeria suggests that this thermophyllous genus migrated into South China by the Middle Pleistocene escaping from glacial cooling and became widespread over this region in the Late Pleistocene beginning from the interglacial stage preceding the Last Glacial Maximum. The analysis of growth rings in the fossil wood and its comparison with those of modern Keteleeria davidiana (Bertrand) Beissner indicates that in the Late Pleistocene of Maoming Basin (29–27 ka BP) there was a humid climate with less pronounced seasonality of precipitation than that seen in the subtropical monsoonal climate of modern northeastern Vietnam. Apparently, the Maoming Basin was influenced by interglacial regime with summer–monsoon circulation. The previously proposed method to distinguish between evergreen and deciduous conifers based on growth ring anatomy, is not reliable because of the wide variance and ambiguity in its results.     

Crocus imperati and Crocus suaveolens (Iridaceae), two controversial endemic crocuses from Central and Southern Italy – morphometrics,lectotypification and chorology

Crocus imperati Ten. and Crocus suaveolens Bertol. are the most controversial endemic crocuses in Italy; they have been interpreted by various authors as different species or infraspecific entities and their chorologies are afflicted by numerous misidentifications. This work, by means of an extensive in vivo study across the whole ranges of the two taxa, and using biometrical investigations, aims at clarifying their status. The names C. imperati and C. suaveolens are typified, several taxonomical complications are discussed and an accurate chorology is outlined. The results show that a single qualitative character is constant (the presence or absence of a bracteole) and two other characters allow discrimination in most cases; their combined use, therefore, ensures certain identification of any single individual. No hybrid individual or intermediate populations were detected and the distributional ranges of the two species were confirmed to be contiguous but not overlapping. As a consequence, treatment of the two taxa at specific level appears to be the most appropriate. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 194–214.     

A new genus and species in the tribe Empoascini (Hemiptera,Cicadellidae, Typhlocybinae) from China

One new leafhopper genus, Circinans, is described with a new species Circinans striata sp. n. as the type species from southern China. Habitus photos and illustrations of male genitalia of this new species are given and differences between the new genus and closely related genera are discussed.     

Trace fossils of the bivalve panopea faujasi,pliocene, Rhodes,Greece

The large bivalve, Panopea faujasi Ménard de la Groye, 1807 is locally abundant in shallow marine sandy facies in Late Pliocene sediments of Rhodes, where it occurs in life position within its burrow. Several Panopea‐trace fossils were sectioned in a vertical plane and others in series of horizontal sections, in order to study them in detail. Morphology of the structures produced by different individuals varied greatly, and even neighbors at the same horizon were unalike in detail. All show retrusive, upward shift in accordance with sedimentary accretion, but some also show protrusive movement as a response to erosive phases. As a response to sedimentation, the bivalve dug its way upwards by moving terrigenous grains and skeletal material from above it to below. In cross section the outline is slightly oval to circular. The longest example of these retrusive structures was preserved to a length of 86 cm and had a diameter of about 15 to 20 cm. As the bivalve has a long lifespan, and burrows deeply, the structures have good preservation potential and can reveal details of depositional history. The trace fossil is named Scalichnus phiale igen. et isp. nov.     

Bichordites monastiriensis from the Pleistocene of southeast Jamaica

Bichordites monastiriensis Plaziat and Mahmoudi 1988, produced by burrowing spatangoid echinoids, is figured and described from shallow marine siliciclastic strata of the Pleistocene Old Pera Beds (Coastal Group) of southeast Jamaica. Its occurrence there represents only the second formal recording of this monospecific ichno‐taxon and extends its geographic range from the Mediterranean region to the Caribbean. The spatangoid species that produced this trace fossil is unknown, but, unlike examples from other areas, it is unlikely to be Echinocardium.     

Plant inclusions from the Cenomanian flints of Archingeay,Les Nouillers,western France

Here, we report flint nodules bearing fossil plant inclusions from the early Cenomanian of the Font‐de‐Benon sand quarry, between the villages of Archingeay and Les Nouillers, Charente‐Maritime, western France. The broken‐open surfaces of these dense siliceous rocks only partly show the whole diversity, which is established using a non‐destructive, multi‐scale approach based on propagation phase‐contrast X‐ray synchrotron microtomography. The conifer genera Brachyphyllum, Frenelopsis, Geinitzia, and Glenrosa have three‐dimensional preservation, and vegetative and reproductive organs are in connection in some cases. The flint nodules formed by silicification of Cenomanian sediments, probably as a result of an intensive period of soil alteration and leaching under warm and wet climate during the Eocene. Although the time was long between the Cenomanian sedimentation and the Eocene silicification, the fossil plants show three‐dimensional external morphology. These mineralizations are interpreted as fine silica microcrystallization over the cell walls and thus are examples of late silica permineralization. The association of foraminifers, echinoids, sponge spicules, and conifers suggests that the Cenomanian sediments were deposited in a coastal and open to the sea palaeoenvironment, near a conifer‐dominated mangrove.     

Palerasnitsynus gen. n. (Trichoptera, Psychomyiidae) from Burmese amber

Palerasnitsynus ohlhoffigen. et sp. n. is described fromBurmese amber of late Albian (Lower Cretaceous) age. This is the first record of the family Psychomyiidae from Burmese amber, and the earliest fossil record of the family. The genus Palerasnitsynusgen. n. differs from all other known psychomyiid genera by the absence of fork III in the forewings.     

Maturation of somatic embryos in conifers: Morphogenesis,physiology, biochemistry,and molecular biology

Summary In the past 15 years tremendons progress has been made towards the development of systems for the induction and development of somatic embryos of coniferous species. Since the first report in 1985, several species have been induced to produce somatic embryos. This has been rendered possible by the development of rational media and improvement of culture conditions, which have resulted in increased embryo quality and higher conversion frequency. Understanding the physiological and biochemical events occurring during in vivo embryogenesis has been fundamental in the design of new protocols for improving the somatic embryogenic process. Specifically, the inclusions of abscisic acid (ABA) and osmotic agents, such as polyethylene glycol (PEG), have been shown to be necessary for the functional development of somatic embryos. In the past few years, physiological and biochemical investigations have been useful in increasing our knowledge on the mode of action of ABA and PEG during embryo development. In comparison with the flowering plants, our understanding on the molecular mechanisms regulating the embryogenic process in coniferous species is still very limited. The application of new molecular techniques is therefore fundamental towards this end. The emphasis of this review is on recent information dealing with the maturation of conifer somatic embryos.     

Thuja sutchuenensis: a rediscovered species of the Cupressaceae

After more than a century, the only conifer species listed as being extinct in the wild (EW) by IUCN-SSC has been rediscovered in the Dabashan Mountains of central China. The history, taxonomy, ecology and conservation of Thuja sutchuenensis are described, and illustrations, based on both the earliest and latest collection of botanical material of this tree, are provided. The taxonomic context of this rare species is discussed.  © 2002 The Linnean Society of London , Botanical Journal of the Linnean Society , 2002, 139 , 305–310.