Search

We describe a new genus of Leliacladus Batista & L.Kunzmann with the type species Leliacladus (Brachyphyllum) castilhoi (Duarte, 1985) Batista & L.Kunzmann gen. nov. et comb. nov., a rare fossil conifer that has been described from the Aptian (Lower Cretaceous) Romualdo Formation of the Araripe Basin, northeastern Brazil. We decided to leave this new fossil-genus unasigned to any existing family as it does not display sufficient number of anatomical characters. We re-studied the type material of the type species as well as we described additional new material from the Aptian Crato Formation of the same basin. The more recently found fossil materials include large portions of leafy shoots excavated from laminated lacustrine limestones. In contrast to the type material, the new material shows the replacement of organic matter by iron oxide, which is suitable for investigating anatomical features of the wood and leaves. The material allowed for a reappraisal of the systematic position of the fossil plant. Together, the morphological and anatomical characters revealed sufficient evidence to separate the conifer from Brachyphyllum and accommodate it in a new fossil-genus. Leliacladus gen. nov. is defined by the presence of comparatively thick and short claviform lateral branches, and the absence of thinner ultimate order branches with gradual tapering axes. The wood is characterized by dense tracheids with uniseriate pitting in the radial walls and cross-fields that possess one or two large pits. The rays are one to three cells high. The epidermises of the densely and helically arranged scale leaves show non-papillate cyclocytic stomatal complexes slightly sunken that are mostly scattered and randomly arranged across the abaxial surface. This combination of characters suggests the material belongs to the conifer families Podocarpaceae or Cheirolepidiaceae. The arrangement of the sparsely branched, but woody shoots of Leliacladus castilhoi gen. nov. et comb. nov. suggest a hypothetical candelabra-like growth habit of the plant, and the remarkable thickness of the axes suggests a hypothetical xeromorphic adaptation to the semiarid paleoenvironment.

We describe a new genus of Leliacladus Batista & L.Kunzmann with the type species Leliacladus (Brachyphyllum) castilhoi (Duarte, 1985) Batista & L.Kunzmann gen. nov. et comb. nov., a rare fossil conifer that has been described from the Aptian (Lower Cretaceous) Romualdo Formation of the Araripe Basin, northeastern Brazil. We decided to leave this new fossil-genus unasigned to any existing family as it does not display sufficient number of anatomical characters. We re-studied the type material of the type species as well as we described additional new material from the Aptian Crato Formation of the same basin. The more recently found fossil materials include large portions of leafy shoots excavated from laminated lacustrine limestones. In contrast to the type material, the new material shows the replacement of organic matter by iron oxide, which is suitable for investigating anatomical features of the wood and leaves. The material allowed for a reappraisal of the systematic position of the fossil plant. Together, the morphological and anatomical characters revealed sufficient evidence to separate the conifer from Brachyphyllum and accommodate it in a new fossil-genus. Leliacladus gen. nov. is defined by the presence of comparatively thick and short claviform lateral branches, and the absence of thinner ultimate order branches with gradual tapering axes. The wood is characterized by dense tracheids with uniseriate pitting in the radial walls and cross-fields that possess one or two large pits. The rays are one to three cells high. The epidermises of the densely and helically arranged scale leaves show non-papillate cyclocytic stomatal complexes slightly sunken that are mostly scattered and randomly arranged across the abaxial surface. This combination of characters suggests the material belongs to the conifer families Podocarpaceae or Cheirolepidiaceae. The arrangement of the sparsely branched, but woody shoots of Leliacladus castilhoi gen. nov. et comb. nov. suggest a hypothetical candelabra-like growth habit of the plant, and the remarkable thickness of the axes suggests a hypothetical xeromorphic adaptation to the semiarid paleoenvironment. [ABSTRACT FROM AUTHOR]

We describe a new genus of Leliacladus Batista & L.Kunzmann with the type species Leliacladus (Brachyphyllum) castilhoi (Duarte, 1985) Batista & L.Kunzmann gen. nov. et comb. nov., a rare fossil conifer that has been described from the Aptian (Lower Cretaceous) Romualdo Formation of the Araripe Basin, northeastern Brazil. We decided to leave this new fossil-genus unasigned to any existing family as it does not display sufficient number of anatomical characters. We re-studied the type material of the type species as well as we described additional new material from the Aptian Crato Formation of the same basin. The more recently found fossil materials include large portions of leafy shoots excavated from laminated lacustrine limestones. In contrast to the type material, the new material shows the replacement of organic matter by iron oxide, which is suitable for investigating anatomical features of the wood and leaves. The material allowed for a reappraisal of the systematic position of the fossil plant. Together, the morphological and anatomical characters revealed sufficient evidence to separate the conifer from Brachyphyllum and accommodate it in a new fossil-genus. Leliacladus gen. nov. is defined by the presence of comparatively thick and short claviform lateral branches, and the absence of thinner ultimate order branches with gradual tapering axes. The wood is characterized by dense tracheids with uniseriate pitting in the radial walls and cross-fields that possess one or two large pits. The rays are one to three cells high. The epidermises of the densely and helically arranged scale leaves show non-papillate cyclocytic stomatal complexes slightly sunken that are mostly scattered and randomly arranged across the abaxial surface. This combination of characters suggests the material belongs to the conifer families Podocarpaceae or Cheirolepidiaceae. The arrangement of the sparsely branched, but woody shoots of Leliacladus castilhoi gen. nov. et comb. nov. suggest a hypothetical candelabra-like growth habit of the plant, and the remarkable thickness of the axes suggests a hypothetical xeromorphic adaptation to the semiarid paleoenvironment. [ABSTRACT FROM AUTHOR]

The genus Classostrobus was established to accommodate unattached Classopollis -containing cones. It is noteworthy that Classopollis as a whole shows significant variation in morphological structure, and male cones bearing Classopollis pollen grains are rarer than vegetative organs of cheirolepidiaceous conifers. A new cheirolepidiaceous microsporangiate cone, Classostrobus doylei , containing Classopollis triangulus pollen grains is described for the first time based on a single specimen from sedimentary rocks exposed in the Carregueira open-cast clay pit complex close to the small village of Juncal, in the Estremadura region(Lusitanian Basin, western Portugal). The plant-bearing horizon from Carregueira is included in the basal part of the Famalicão Member of the Figueira da Foz Formation, considered to be of late Aptian – early Albian age. The new microsporangiate cone is small, about 2.0 mm long and 1.5 mm wide, ovoid in shape and of typically coniferous structure, probably belonging to Pseudofrenelopsis zlatkoi. The male cone consists of about 16 peltate, imbricated microsporophylls of deltoid shape. Each sporophyll is composed of a stalk and deltoid head showing abaxially 4–5 ovoid pollen sacs. The marginal parts of the sporophylls display long and unicellular trichomes. The observed in situ pollen grains are triangular to subcircular in outline, 16–28 μm in diameter, with an equatorial girdle, subequatorial rimula, proximal trilete scar and a distal cryptopore. The pollen ultrastructure is typical for Classopollis , except for the destroyed condition of the exine. The in situ pollen grains under study are consistent with the data on known dispersed Classopollis triangulus. • A new cone Classosstrobus doylei is described from the Lower Cretaceous of Portugal. • The new cheirolepidiaceous cone contains Classopollis triangulus pollen grains. • The morphology and ultrastructure of Classopollis pollen grains were described. • The study provides new information on key taxonomic features of Cheirolepidiaceae. [ABSTRACT FROM AUTHOR]

We report new ichnites corresponding to a trackway composed of three tetradactyl pedal footprints and plant remains near Southeastern Guatacondo, Tarapacá Region, within the transition of Majala and Chacarilla Formations (Late Jurassic-Early Cretaceous). The fossils were found in the context of a Copper Mining road construction at the PK23 site, Quebrada Blanca Phase 2 project, by the Teck Mining Company Quebrada Blanca S.A. We performed stratigraphical, paleobotanical, and paleoichnological studies, along with the footprint characterization and comparisons by Principal Component Analysis, and Discriminant Analysis of I-II, II-III and III-IV interdigital angles, using a large tetradactyl footprint morphological database of potential producers (dinosaurs, crocodiles, lepidosaurs, and pterosaurs). Additionally, we performed 3D pedal computer modeling kinematic analysis of the Chilesaurus diegosuarez i's 3D tetradactyl foot under two different sedimentary conditions (i.e. hard soil with superficial impression, and soft sediment with a penetrative impression), to test it as a potential trackmaker. The stratigraphic section reveals an association of siliciclastic facies, formed by the intercalation of fine-grained sandstones and wackes, with ripple marks, cross and horizontal lamination, evidencing intermittent moderate to low sedimentation energy. Among the plant material, several organs of the family Cheirolepidiaceae were identified such as, leaves and leafy branches of Brachyphyllum type, Classostrobus pollen cone, ovuliferous scales, and wood fragments related to Cupressinoxylon. The monodominance of Cheirolepidiaceae among the preserved macroflora allows inferring the characteristics of the environment in which the plants lived, highlighting halophytic, and temporarily arid conditions. Evidence as a whole, permits to interpret the depositional environment as an arid deltaic-littoral plain, temporarily covered with an ephemeral water layer associated with a stunted woody vegetation, in which terrestrial vertebrates walked by. Despite the low predictive power of the multivariate analysis, due to the various sources of morphological variability inherent to footprint formation, the PK23 footprints seem to better correspond to Dinosauria or Avialae as the most likely producers, rather than to Lepidosauria or Crocodylia, discarding the dinosaur Chilesaurus due to very low interdigital mediolateral rotation capabilities. • We studied a palaeobotanical and paleoichnological record exposed during the construction of a road leading to a copper mine. • Majala is the most likely bearing Formation. Its depositional environment is interpreted as an arid deltaic-littoral plain. • Different plant organs identified are all attributables to the Cheirolipidiaceae Family. • We performed multivaried analyses on an extensive tetradactyl footprint interdigital angle database. • We built a 3D kinematic model of Chilesaurus foot in order to compare it as a potential producer • PK23 footprintsbetter correspond to Dinosauria or Avialae as the most likely producer, but is distinct from Chilesauridae. [ABSTRACT FROM AUTHOR]

T heCretaceous/Paleogene (K/Pg) boundary Classopollis pollen “spike” in Patagonia, Argentina, is viewed as a singular event with no coeval analog anywhere else in the world. Review of global palynological records, however, reveals that similar K/Pg boundary Classopollis spikes involving monotaxial C. classoides (Pflug) Pocock and Jansonius assemblages have previously been reported from the Colorado Basin, Argentina, as well as the Tarim Basin, China, suggesting that this was a global phenomenon. The presence of this morphotaxon in the Danian strata of western North America has previously been interpreted as evidence of reworking from older, pre-Turonian (i.e., Triassic through Early Cretaceous) sediments during the Laramide orogeny. This hypothesis appears supported by the results of contemporary detrital zircon studies coupled with the physical degradation of pollen. However, the interpretation that all Danian examples of this pollen, particularly those from coal deposits, have been reworked from much older sediments is questioned on the basis of this review. Within this context, assorted hypotheses regarding the enigmatic coup de grâce of Classopollis-producing Cheirolepidiaceae are also considered, particularly the hypotheses that the ecologic distribution of Cheirolepidiaceae retracted to include xeric, upland habitats (e.g., the Rocky Mountains) or brackish-water, physiologically dry habitats (e.g., the margin of the Cannonball Sea) during the Late Cretaceous and Danian. [ABSTRACT FROM AUTHOR]

We report the first Hettangian theropod tracksite (~200 Ma) yielding a rich accumulation of plant remains from the Bleymard Strait (southern France). It constitutes an excellent opportunity to reconstruct lowermost Jurassic ecosystems hosting dinosaurs and which are still poorly documented in this area. Two morphotypes of tridactyl tracks are distinguished. They share similarities with Grallator and Kayentapus. Plant-bearing beds yield abundant leafy axes (Pagiophyllum peregrinum), male cones (Classostrobus sp.), wood (Brachyoxylon sp.) and pollen of conifers (Classopollis classoides). Sedimentological, petrological and mineralogical analyses demonstrated that, in the Dolomitic Formation from Bleymard, the palaeoenvironment progressively evolved from (1) a shoreface to a foreshore domain; to (2) a shallow environment that is restricted or occasionally open to the sea; then to (3) an intertidal to supratidal zone. The Hettangian theropod ecosystem of the Bleymard Strait was composed of tidal flats that were periodically emerged and bordered paralic environments inhabited by a littoral conifer-dominated forest in which Cheirolepidiaceae were the main component. The paucity of the palaeobotanical assemblage, as well as the xerophytic characteristics of Pagiophyllum, show that flora from Bleymard was adapted to withstand intense sunlight and coastal environments exposed to desiccant conditions coupled with salty sea spray, and dry conditions. These features are those of a conifer-dominated flora under a tropical to subtropical climate. The flora as well as the clay mineral analyses suggest contrasting seasons (cyclically dry then humid). This study supports that theropods were abundant and particularly adapted to this type of littoral environment bordering Cheirolepidiaceae-dominated forests. [ABSTRACT FROM AUTHOR]

Abstract The Lower Cretaceous Guantou Formation is known as an important horizon for the Cretaceous petrified woods in southern China. Though abundant Cretaceous wood remains have been found in this formation, only one species has been recognized. A new coniferous wood, Brachyoxylon zhejiangense sp. nov. is described from the Lower Cretaceous Guantou Formation in Xinchang of Zhejiang Province, southeastern China. Anatomically, the new species is characterized by obscure annual rings, mixed type of radial pitting, araucarioid cross-field pits and uniseriate xylem rays. The finding of Brachyoxylon zhejiangense sp. nov. represents the first well-defined record of Brachyoxylon in southeastern China, and enriches the diversity of the Early Cretaceous petrified wood in southern China. Additionally, the new finding sheds new light on further understanding the floral composition, especially the forest vegetation type of the southern phytoprovince in the late Early Cretaceous. Diverse compressed leaf fossils of Cheirolepidiaceae have been described from the Guantou Formation in the fossil locality of the present petrified wood. The co-occurrence of Brachyoxylon zhejiangense sp. nov. and those cheirolepidiaceous leaf fossils provide additional evidences to support that Brachyoxylon may be systematically related to the Cheirolepidiaceae.

A comprehensive nomenclatural analysis of the generic and suprageneric names used for an extinct conifer group, treated as a distinct family under the names Cheirolepidaceae, Cheirolepidiaceae or Hirmeriellaceae or a distinct order, Cheirolepidiales or Hirmeriellales, is presented. The fossil generic name Cheirolepis Schimp. (1870) is an illegitimate later homonym of the name of the extant genus Cheirolepis Boiss. (1849; Asteraceae). It has been superfluously substituted with a new generic name, Cheirolepidium Takht. (1957). The authorship and place of valid publication of Cheirolepidium is corrected based on newly discovered information. The correct generic name for these fossils is Hirmeriella Hörhammer (1933), established originally for a cone consisting of persistent bract scales lacking seed scales, because it has priority over the generic name Cheirolepidium Takht. All three fossil generic names were employed for the same fossil cone taxon, which represented different stages of maturity of the same seed cone. The inclusion of both Cheirolepis and Cheirolepidium under Hirmeriella was proposed by Jung (1968) in his formal lectotypification of the type of the genus name, Cheirolepis muensteri (≡ Brachyphyllum muensteri), with a cone specimen that was cited in the protologues of the types of both genera, Cheirolepis muensteri and Hirmeriella rhaetoliassica. The lectotypification of Cheirolepis muensteri and Hirmeriella rhaetoliassica using the same elements results in the three generic names being homotypic synonyms. As a consequence, the correct family name for the fossil conifer group is Hirmeriellaceae, to be proposed for conservation against Cheirolepidiaceae. Cheirolepidaceae is inadmissible being based on the illegitimate later homonym Cheirolepis Schimp. and thus itself illegitimate. [ABSTRACT FROM AUTHOR]

Fossil wood is one of the most important proxies for terrestrial vegetation composition and continental paleogeographical reconstruction in Earth's history. The conifer wood Brachyoxylon is commonly found in Mesozoic deposits in Europe, Africa, South America, and Antarctica with more than one hundred known occurrences to date. However, only few occurrences (∼ 5%) are so far documented in China of East Asia. Here, we describe a fossil wood specimen from the Middle Jurassic Upper Shaximiao Formation at Yongxin of Chongqing City in southeastern Sichuan Basin, China, exhibiting typical Brachyoxylon anatomy with mixed radial tracheid pitting and araucarioid cross-field pitting. According to the characters of radial tracheid pitting, cross-field pitting, and ray height, the wood is recognized as Brachyoxylon trautii (Barale) Philippe 1995. To better understand the paleobiogeography of the Mesozoic Brachyoxylon , a global survey of its occurrences is performed, which shows that Brachyoxylon was globally expanding over time with the widest geographic distribution in the Cretaceous. • New occurrence of Brachyoxylon in the Sichuan Basin, China. • Global survey of occurrences of Brachyoxylon. • Brachyoxylon with its widest geographic distribution in the Cretaceous. [ABSTRACT FROM AUTHOR]

Abstract Frenelopsis justae sp. nov. is reported from the middle – lower upper Albian Escucha Formation of San Just, Teruel province, Spain. It shows micro-morphological features hitherto undescribed in the genus Frenelopsis including: (1) individual stomatal apparatus comprised of only three subsidiary cells; (2) clusters of 2–3 stomatal apparatus sharing a single subsidiary cell; (3) stomatal rows that bifurcate; and (4) an internal, cylindrical, cell layer preserved between the adaxial and abaxial cuticles. The morphology in the genus is reinterpreted, the long leaf sheath consisting of the proximal abaxial surface of 2–3 fused leaves lacking visible sutures with short distal free parts. Therefore, the generic diagnosis is emended, and new microscopic features added. We show that the appearance, morphology and structure of the leaf surfaces, free leaf tips, and stomatal apparatus are highly variable and regard them as innovation hot-spots in Frenelopsis species. We emphasize the need to perform thorough quantitative analysis of Frenelopsis morphology, including description of metrics variance, to improve our knowledge of its taxonomy, phenotypical plasticity and evolutionary trends. Highlights • The new species Frenelopsis justae is described. • Stomatal apparatus of 3 subsidiary cells are firstly described for Frenelopsis. • The leafy stem morphology of the genus is reinterpreted. • Emendation of the genus diagnosis is provided. • Free leaf tips, stomata and leaf surface are variability hot-spots in Frenelopsis. [ABSTRACT FROM AUTHOR]

A Cheirolepidiaceae Frenelopsis teixeirae from the Lower Cretaceous of the Santa Susana Formation, near Torres Vedras locality (Estremadura region, western Portugal), is analyzed by means of Fourier Transform Infrared (FTIR) spectroscopy in Attenuated Total Reflection (ATR) mode at both micro and macro scales. This analytical technique (ATR-FTIR spectroscopy), which requires minimal sample preparation and a small amount of material, is used to evaluate the chemical composition of the F. teixeirae cuticles. For this, functional groups (i.e., specific groupings of atoms within molecules), that compose the complex chemical structure making up the F. teixeirae cuticles, are detected, analyzed, and interpreted from the resulting spectra. The Frenelopsis material comprises compressions of eighteen leafy axes with very well-preserved cuticles. Previously reported chemical information derived from transmission FTIR spectra of the foliar cuticle of the podocarp Squamastrobus tigrensis from the Lower Cretaceous of Argentina is used for comparison in order to assess the existence of a distinctive spectroscopic pattern for this Portuguese taxon. Semi-quantitative data derived from FTIR spectra of both fossil taxa were statistically analyzed using principal component analysis (PCA). The F. teixeirae cuticles have a lower contribution of C = O stretch and a lower degree of biopolymeric matrix cross-linking (higher CHal/C = O ratio) than those of S. tigrensis. Despite the existing differences between both conifers, spectroscopic patterns characterizing each fossil taxon are not fully distinctive from a chemotaxonomic perspective. This is mainly related to the relatively variable morphological cuticular features (e.g., trichomes) and to the biomacropolymeric chemistry among the leaves of each fossil taxon. [Display omitted] • Frenelopsis teixeirae from the Lower Cretaceous (Portugal) is chemically studied. • Frenelopsid cuticles are analyzed using micro and macro-ATR-FTIR spectroscopy. • FTIR spectroscopy allows identifying functional groups present at cuticular level. • Frenelopsis teixeirae cuticles are highly aliphatic with a low aromatic contribution. • Low cross-linking of ester bonds in probably both biomacropolymers: cutins and cutans. [ABSTRACT FROM AUTHOR]

A new cheirolepidiaceous conifer microsporangiate cone Classostrobus archangelskyi is described from the Carregueira opencast clay pit complex near the village of Juncal, in the Lusitanian Basin of central-western mainland Portugal. The plant-bearing horizon belongs to the Famalicão Member of the Figueira da Foz Formation, considered to be of Lower Cretaceous (upper Aptian–lower Albian) age. The new microsporangiate cone is characterised by the presence of distinctive and unusual pollen assigned to the genus Classopollis. The microsporangiate cone is ovoid and small, comprising only a few microsporophylls, each with a stalk and deltoid head bearing 4–5 pollen sacs. The new Portuguese species is compared to other microsporangiate cones attributed to the genus Classostrobus. The Classopollis pollen grains found in situ are characterised by a microechinate sculpture and typical ultrastructure. The pollen grains were studied using SEM, TEM and transmitted light microscopy. The studied pollen shares strong similarities with Classopollis martinotii , Classopollis torosus , but particularly with Classopollis noelii. The new microsporangiate cone Classostrobus archangelskyi co-occurs with frenelopsid leafy shoots of Frenelopsis antunesii, and their common association is suggested. • A new cheirolepidiaceous pollen cone is described from the Cretaceous of Portugal. • The new species Classosstrobus archangelkyi contains Classopollis pollen grains. • Morphology and ultrastructre of Classopollis pollen grains are described. • The study provides important information regarding to the internal cone morphology. • The new cone is probably attributable to the Frenelopsis antunesii -producing plant. [ABSTRACT FROM AUTHOR]

A new Cenomanian amber- and plant-bearing deposit has been discovered at Neau, in the Mayenne department (France). The Cenomanian fossiliferous lignites are located in karst filling in a substratum of Cambrian limestones. The amber corresponds mainly to tiny millimetric grains, devoid of arthropod inclusions, but rich in microorganisms, especially the sheated bacteria Leptotrichites resinatus, and containing pollen grains (Classopollis) and wood fibers (Araucariacae or Cheirolepidiaceae). The lignites provide abundant conifer and ginkgoale cuticle fragments (Frenelopsis, Eretmophyllum) and a lot of palynomorphs (e.g. Gleicheniidites senonicus, Cyathidites, Deltoidospora, Appendicisporites and Cicatricosisporites). The chemical signature of the amber suggests it was produced by conifers of the extinct family Cheirolepidiaceae. According to the palynological assemblage, the age of the lignites is upper lower Cenomanian or lower mid Cenomanian. The deposit environment corresponded to the upstream portion of a mangrove or the most inner part of a lagoon.

Abstract The Cheirolepidiaceous conifer Suturovagina intermedia Chow et Tsao is reported from the Lower Cretaceous of Wangqing, Jilin Province in northeastern China, and its leaf cuticles were studied in detail using scanning and transmission electron microscopies and EDS. The data obtained were compared with those of the previous study on the same species from the Lower Cretaceous of the type locality Nanjing, Jiangsu Province in eastern China. Despite the general similarity in gross morphology and leaf cuticular structure, there are a number of differences in leaf cuticular ultrastructure and element composition (EDS data) between specimens from the two localities. Among them, 14 differences are potential taxonomical characters. Of them, 7 might be of importance at the species/genus level, and 7 are possible characters at the family level. There are also 23 differences, i.e., 7 cuticle ultrastructural characters of ordinary epidermal cell cuticles and 5 subsidiary cell cuticles, plus 11 EDS ratios of cuticles, believed to be of ecological significances. This paper presents the first case to make comparative palaeoenvironmental analyses based on leaf cuticle ultrastructure and element composition of the same taxon from different areas. It shows that Suturovagina intermedia was an inhabitant of a lower xerothermic environment in Wangqing, instead of being a higher xerothermic environment, such as in the type locality Nanjing. The conclusion obtained is well-supported by the evidence of the element composition (EDX data) of the matrix and the associated biotic composition of the fossil-bearing beds from the two localities. It is the first attempt to search for the environmental footprint in fossil plant cuticles based on their element composition. Highlights • Suturovagina intermedia (Cheirolepidiaceae) is reported from Wangqing, Jilin, China. • There are differences of ecological significances between the specimens from Wangqing and the type locality Nanjing. • The differences include 7 cuticle ultrastructural characters and 11 EDS ratios of cuticle element composition. • S. intermedia in Wangqing inhabited an environment which was not as hot or dry as that of the type locality. • The conclusion is supported by EDX data and the associated biotic composition of the fossil-bearing beds. [ABSTRACT FROM AUTHOR]

The Jurassic–Cretaceous boundary interval in northwest Europe is characterised by a distinctive climatic change from pronounced aridity toward more humid conditions. In order to better understand the timing and evolution of the environmental dynamics related to this climatic change, terrestrial and aquatic palynomorphs (spores, pollen, dinoflagellate cysts, freshwater algae) have been studied from two recently drilled cores. The cores, which are both located in the Lower Saxony Basin (northern Germany), provide two 139 m and 134 m thick non-marine successions embedded in a high-resolution biostratigraphic framework. The lower part of the cores can be attributed to the Münder Formation (upper Tithonian–middle Berriasian), the upper part to the Bückeberg Group (middle–upper Berriasian). For reconstructing the arid to humid climate transition 110 samples have been analysed for their palynological content. In the Lower Saxony Basin, the late Jurassic–earliest Berriasian vegetation was dominated by cheirolepidiacean conifer forests growing under arid conditions along a coastal belt. A marked decline in cheirolepidiacean pollen and the spread of pioneering plants records an increase in seasonal humidity in the early–mid Berriasian. In the mid–late Berriasian the presence of highly diverse floras reflects even more humid and warm conditions. Fluvio-deltaic mixed swamp forests, which grew landwards behind the coastal belt were composed of conifers, ferns, lycopods, horsetails, bryophytes, ginkgos, cycads and Bennettitales. Cheirolepidiaceans, probably forming part of mangrove-type plant communities, remained an important component of the coastal flora. The climatic shift correlates to the upper Subcraspedites lamplughi –middle Heteroceras kochi ammonite zones of the marine Boreal zonation scheme and is synchronous to the early–mid Berriasian shift from arid to humid recorded from southern England. [ABSTRACT FROM AUTHOR]

The Cheirolepidiaceae are an extinct family of conifers that was highly diverse during the Mesozoic, particularly at lower latitudes. Cheirolepidiaceous remains assigned to the genera Frenelopsis and Pseudofrenelopsis are very common in the Early Cretaceous floras of Portugal. A new species Pseudofrenelopsis dinisii is described from the Lower Cretaceous sediments (probably lower Hauterivian) of the Santa Susana Formation, at the Vale Cortiço site in the Lusitanian Basin of western Portugal. The new taxon is described based on morphology of the vegetative shoots and cuticular features. Pseudofrenelopsis dinisii consists of leafy shoots with spirally arranged leaves with an attenuate apex that enclose the stem, while leaves of the Brachyphyllum type occur on terminal shoots. The leaf margins bear well-developed trichomes; the stomatal apparatus is deeply sunken and strengthened by papillae, and the cuticle is moderately thick. Like other frenelopsids, P. dinisii displays these and other typically xeromorphic features, but although many other frenelopsids are associated with independent evidence for arid or saline conditions, the palynoflora from the bed with P. dinisii is rich in spores and shows no evidence of marine influence. Pseudofrenelopsis dinisii may represent the non-arid and non-saline end of the wide spectrum of environments occupied by Cheirolepidiaceae; its xeromorphic features may be adaptations to occasional periods of strong water stress. Comparisons with other sequences suggest a trend in the ecological preferences of both Pseudofrenelopsis and Frenelopsis from alluvial and upper deltaic environments before the Albian to saline coastal environments in the Albian and Cenomanian. • A new species Pseudofrenelopsis dinisii is described from the Portuguese Cretaceous. • The new species adds new information on the morphological variation in frenelopsids. • Its xeromorphic features suggest adaptations to occasional periods of water stress. • Highlights the importance of the frenelopsids in the Early Cretaceous floras. [ABSTRACT FROM AUTHOR]

The flora preserved in upper Aptian rocks of South America and Africa is typical of warm climate conditions and commonly associated with semi-arid to arid climate. Warmth-loving conifers of the family Cheirolepidiaceae and their pollen Classopollis are recorded in upper Aptian rocks in most of the South Atlantic margin basins. However, an increase in indicators of humid conditions (e.g., ferns) is recorded in most sedimentary basins of Brazil. The method of indicator species analysis (IndVal) was applied as a tool for reconstructing the vegetation during the late Aptian. The IndVal index expresses which taxa are strongly associated with particular groups of samples. The vegetation reflects climate changes, and the IndVal indices illustrate how the taxa interacted through time and reveal patterns in the changing composition of the vegetation. The material studied derives from two well sections drilled through the Riachuelo Formation in the Sergipe Basin, GTP-17-SE (Angico Member, 70 samples) and GTP-24-SE (Taquari Member, 108 samples). The indicator species are strongly associated with particular stratigraphic intervals. IndVal indices for the Angico section indicate seven taxa associated with four intervals, viz. Classopollis classoides (Interval AS-1); Callialasporites segmentatus and Cicatricosisporites avnimelechi (Interval AS-2); Verrucosisporites spp. and Cicatricosisporites microstriatus (Interval AS-3); Araucariacites australis and Cyathidites spp. (Interval AS-4). Values for the Taquari section indicate nine taxa associated with four intervals, viz. Classopollis classoides (Interval TS-1); Uesuguipollenites callosus , Callialasporites segmentatus Bennettitaepollenites regaliae , Cyathidites spp., Cicatricosisporites spp. and Araucariacites australis (Interval TS-2); Retitriletes spp. (Interval TS-3); Araucariacites australis and Verrucosisporites spp. (Interval TS-4). Two phases, dry and wet, are recognized in both sections. The dry phase is characterized by high to very high abundance of Classopollis classoides . A conspicuous change in vegetation is recorded, with an increase in ferns and upland flora, in particular Araucariacites australis . A . australis is the second most abundant terrestrial palynomorph. In the late Aptian of South America and Africa Araucariacites is generally associated with an upland flora and warm and humid climates, which may explain its association with fern spores. The replacement of Classopollis by Araucariacites and ferns reflects a change from a dry to wet phase. The change in flora may be the result of dislocation of the Intertropical Convergence Zone (ITCZ) and a relative sea-level rise. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Plants preserved in different fossil modes provide complementary data concerning the paleobiology and evolutionary relationships among plant groups. New material from the Early Jurassic of Patagonia shows the importance of combining these sources of information, as we describe the first compression/impression fossils of Pararaucaria, a genus of the extinct conifer family Cheirolepidiaceae previously known from permineralized fossils. These fossils extend the temporal range of this genus and may allow its wider recognition in the fossil record. METHODS: We studied fossil plants from the Early Jurassic (Pleinsbachian-Toarcian) locality of Taquetrén in Patagonia, Argentina using standard paleobotanical preparation and description techniques. KEY RESULTS: Pararaucaria taquetrensis consists of isolated ovuliferous scales and small seed cones with helically arranged bract-scale complexes attached to scale-leaf foliage. Bract-scale complexes consist of separated bracts and ovuliferous scales with two seeds and three broad distal lobes. CONCLUSIONS: Pararaucaria taquetrensis represents the oldest known Cheirolepidiaceae seed cones from the Southern Hemisphere, and this material highlights the importance of compression and impression fossils in understanding the distribution of fossil taxa. This material also suggests that Cheirolepidiaceae cone scales can be easily confused with those of another common conifer family, the Araucariaceae, which has important implications for accurately understanding Mesozoic conifer diversity and paleoecology. [ABSTRACT FROM AUTHOR]

Pararaucaria , a genus of the extinct conifer family Cheirolepidiaceae, was previously identified from permineralized fossils. This genus reflects important changes in the phylogeny and evolutionary biology of Cheirolepidiaceae. We describe a new species of Pararaucaria (Pararaucaria laiyangensis) from the Lower Cretaceous of the Laiyang Formation in Shandong Province, eastern China using standard paleobotanical descriptions and micro-computed tomography techniques. P. laiyangensis consists of small seed cones with helically arranged bract-scale complexes, isolated ovuliferous scales, and associated scale-leaf foliage with obvious cuticle structures. Bract-scale complexes consist of separated bracts and ovuliferous scales with one seed and three distal lobes. Cuticles consist of haplocheilic and monocyclic stomata arranged in longitudinal rows all over the surface. We assigned the phylogenetic relationship of P. laiyangensis within Cheirolepidiaceae based on the parsimony analyses, and highlight the homology of ovuliferous scales in Pararaucaria and Araucaria according to the comparison with ovuliferous scale structures of all major conifers. Moreover, this species increases our understanding of the dominant tree element of the Laiyang fossil forest, providing the first evidence for ovulate cheirolepidiaceous cones in Asia based on the global distribution of Cheirolepidiaceae reproductive organs. • A new species of Pararaucaria was described from the Early Cretaceous of the Laiyang Formation in eastern China. • The homology of ovuliferous scales in Pararaucaria and Araucaria was highlighted. • This species provides the first evidence for ovulate cheirolepidiaceous cones in Asia based on the global distribution. [ABSTRACT FROM AUTHOR]

A new cheirolepidiaceous conifer Pseudofrenelopsis zlatkoi is described from the Lower Cretaceous (late Aptian-early Albian) of the Figueira da Foz Formation in the Lusitanian Basin, western Portugal. The new species is similar to Pseudofrenelopsis parceramosa , but differs in having thinner cuticle, expanded nodal areas and ridged internodes. It is compared in several respects to thirteen other species described in the past. Pseudofrenelopsis zlatkoi is characterised by ridged internodes. Their morphology is mirrored in the disposition of epidermal structures, having usually ridges built by elongate costal ordinary cells. The grooves between ridges are formed by uniserial or biserial rows of stomata. Stomata of abaxial cuticle are surrounded typically by five subsidiary cells bearing papillae and additionally surrounded by a rim, while on the adaxial cuticle stomata are typically without papillae, being surrounded by a simple rim (Florin ring). The large papillae are equipped with delicate microemergenses on their surface. • A new species Pseudofrenelopsis zlatkoi is described from the Portuguese Cretaceous. • The new taxon is distinct in having expanded nodes and ribbed internodes. • The new finding adds new information on the morphological variation in frenelopsids. • Supports the importance of the Cheirolepidiaceae in the Early Cretaceous floras. [ABSTRACT FROM AUTHOR]

Coprolites from the Early Cretaceous vertebrate bone-bed at Ariño in Teruel, Spain, were analyzed geochemically and palynologically. They contain various inclusions, such as small bone fragments, abundant plant remains, pollen, and spores. We attribute the coprolites to carnivorous dinosaurs based partly on their morphology together with the presence of bone fragments, and a high content of calcium phosphate (hydroxylapatite) with calcite. Well-preserved pollen and spore assemblages were identified in all coprolite samples and a slightly poorer assemblage was obtained from the adjacent sediments, both indicating an Early Cretaceous (Albian) age. This shows that the coprolites are in situ and also confirms previous age determinations for the host strata. The depositional environment is interpreted as a continental wetland based on the palynoflora, which includes several hydrophilic taxa, together with sparse occurrences of fresh-water algae, such as Ovoidites , and the absence of marine palynomorphs. Although the coprolites of Ariño samples generally are dominated by pollen produced by Taxodiaceae (cypress) and Cheirolepidiaceae (a family of extinct conifers), the sediment samples have a slightly higher relative abundance of fern spores. The distribution of major organic components varies between the coprolite and sediment samples, which is manifest by the considerably higher charcoal percentage within the coprolites. The high quantities of charcoal might be explained by a ground-dwelling species, feeding on smaller vertebrates that complemented its diet with plant material from a paleoenvironment were wild fires were a part of the ecosystem. The state of preservation of the spores and pollen is also more detailed in the coprolites, suggesting that encasement in calcium phosphate may inhibit degradation of sporopollenin. [ABSTRACT FROM AUTHOR]

The stable carbon isotope compositions and the stomatal parameters (stomatal density and stomatal index) of four Cheirolepidiaceae species, Brachyphyllum ningxiaensis , Brachyphyllum obtusum , Pseudofrenelopsis dalatzensis and Pseudofrenelopsis gansuensis , were analyzed to recover the late Early Cretaceous atmospheric CO 2 levels. The fossil plants were collected from 5 consecutive sedimentary members of the uppermost Zhonggou Formation. Based on the stomatal data, the estimated palaeo-atmospheric CO 2 concentrations in the Jiuquan Basin during the late Early Cretaceous were 1060–882 ppmv based on the carboniferous standardization and were 641–531 ppmv based on the recent standardization; the p CO 2 values present at first a decreasing and then an increasing trend within the sedimentary time of the five members. The δ 13 C p values based on the 21 Brachyphyllum specimens showed a large variation, which ranged from −20.98‰ to −25.69‰, with an average of −24.2‰. The values also identified a C3 photosynthetic pathway for the Brachyphyllum specimens. The predicted δ 1 3 C a values varied from −2.1‰ to −6.38‰, with an average of −5.03‰. These two proxies were irregular within the different members; therefore, the correlation with the change in atmospheric CO 2 concentrations was not significant. Moreover, a water-stressed environment was proposed based on the δ 13 C values of the present fossil plants, a proposal that was also supported by the previous palaeobotanical, palynological and stratigraphical evidence. In the present study, an inconsistent relationship between the stable carbon isotope and the stomata values was apparent, which most likely indicated that the stomata numbers of the plant were more sensitive to the variation in the concentration of the atmospheric CO 2 , whereas the δ 13 C values were sensitive to the moisture conditions. [ABSTRACT FROM AUTHOR]

The following 15 generic names are recommended for conservation: Angaropteridium against Neurogangamopteris, Beania against Sphaereda, Bucklandia Brongn. against Bucklandia Sternb. and Conites, Coniopteris against Polystichites, Equisetites against Oncylogonatum with a conserved type, Juglandicarya against Hyhothya with a conserved type, Lepidophloios against Yuccites, Lepidopteris against Aspidioides, Marattiopsis with a conserved type, Nilssonia with that spelling, Pityostrobus against Zamiostrobus, Scytophyllum Bornem. against Scytophyllum Eckl. & Zeyh., Sphenozamites with a conserved type, Verrucosisporites with that spelling, and Vertebraria Royle ex McCoy against Vertebraria Roussel. The following 3 species names are recommended for conservation. Beania gracilis against Sphaeredaparadoxa, Equisetum columnare (Equisetites colunmare) against Oncylogonatum carbonarium with a conserved type, and Scytophyllum bergeri with a conserved type. The following 4 generic names are not recommended for conservation: Carpolithus with that spelling, Crowella against Actinostrobites and Frenelites, Cyclodendron against Subsigillaria and Eusigillaria, and Pecopteris against Filicites, as also are the following 22 names, all originally hyphenated, and proposed for conservation with these spellings: Abiespollenites, Alatisporites, Apiculatasporites, Cicatricosisporites, Densosporites, Elongatosporites, Faguspollenites, Gnetaceaepollenites, Granulatisporites, Juglanspollenites, Palaeoavena, Piceaepollenites, Poacordailes, Pseudoaiaucaria, Quercipollenites, Sabalpollenites, Sequoiapollenites, Setosisporites, Sparganiaceaepollenites, Tuberculatisporites, Ulmipollenites, Valvisporites. The following 2 species names are not recommended for conservation: Dalbergia reticulata Merr. against D. reticulata Ettingsh. and Sphenophyllum indicum (Vertebraria indica) against Vertebraria australis and Clasteria australis. The following family name is not recommended for conservation: Cheirolepidaceae. Change of authorship of Catamites, nom. cons, from Brongniart in 1828 to Sternberg in 1820 and the concomitant deletion of "Calamitis Sternb.", nom. rej. was recommended. The following 3 names are recommended for outright rejection: Filicites, Frenelites, and Solenostrobus. The committee judged the names Cheirolepidiaceae and Cheirolepidaceae to be not confusable. [ABSTRACT FROM AUTHOR]

Coniferales are represented during the Early Cretaceous in northern South America both by macrofossils and palynomorphs of the families Araucariaceae and Cheirolepidiaceae. Fossils of Cheirolepidiaceae are often abundant in coastal deposits; plants of this family are considered to have grown under semiarid to arid climate conditions because of characteristic anatomical features which include several adaptations to aridity and/or salinity. Here histologically preserved specimens of Pseudofrenelopsis from laminated limestones of the Crato Formation (Araripe Basin, NE Brazil) were studied by light and scanning electron microscopy. A new species Pseudofrenelopsis capillata sp. nov. is described which seems to have grown exclusively at the Early Cretaceous (sub)paleoequatorial area of South America and may be therefore endemic. The new taxon may have grown in a riparian environment along the borders of a large lake as a minor constituent of the surrounding vegetation. [ABSTRACT FROM AUTHOR]

To date, the vast majority of fossils described for the extinct conifer family, the Cheirolepidiaceae, have been reported from compression/impressions primarily from Cretaceous rocks; there are fewer reports from permineralizations and the Jurassic. New specimens have recently been discovered in siliceous blocks composed of fusainized layers of plant remains that alternate with fine-grained sediments from the Carapace Nunatak (Lower Jurassic) locality of southern Victoria Land, Antarctica. Specimens were prepared using standard serial cellulose-acetate peel technique, transmitted-light microscopy, and SEM analysis. The cones are ellipsoidal, up to 5.5 mm long, and consist of helically arranged microsporophylls, each with a slender stalk containing a single vascular bundle; the distal lamina is peltate and most closely resembles those of the Classostrobus . Four to seven pollen sacs are arranged in an annular cluster abaxial to the sporophyll stalk. In situ Classopollis pollen ranges from 18 to 60 μm in equatorial diameter with an average diameter of 30 μm. In addition to these well-preserved pollen cones there is a large diversity of vegetative conifer remains within the Carapace Nunatak material including leaf and stem fragments. The discovery of the pollen cones in combination with vegetative remains provides additional information on the reproductive biology of the Cheirolepidiaceae and increases the probability of developing a whole-plant concept for this Jurassic permineralized conifer. [ABSTRACT FROM AUTHOR]

Cheirolepidiaceae leaves and pollen are recorded from Valanginian–Albian strata of southeastern Australia that were deposited at high-latitudes under cool, moist climates in contrast to the semi-arid or coastal habitats preferred by many northern Gondwanan and Laurasian representatives of this group. Leaves of this family are characterized by thick cuticles and cyclocytic stomata with randomly oriented apertures, arranged in scattered or longitudinal rows or bands. Stomata are deeply sunken and surrounded by four to six subsidiary cells that bear one or two ranks of prominent overarching papillae, which may constrict the mouth of the pit. Three new taxa ( Otwayia denticulata Tosolini, Cheirolepidiaceae cuticle sp. A and sp. B) are distinguished based on cuticular features, adding to several previously documented cheirolepid conifers in the Early Cretaceous of eastern Australia. Cheirolepidiaceae foliage is preserved predominantly in fluvial floodbasin settings and is interpreted to be derived from small trees occupying disturbed or low-nutrient sites. The foliage is associated with Classopollis / Corollina pollen and roots characterized by prominent mycorrhizal nodules. A Cenomanian Classopollis type recognised from Bathurst Island, Northern Australia, is recorded for the first time from the Early Cretaceous Eumeralla Formation, Otway Basin. Classopollis locally is rare in Valanginian–Barremian strata of Boola Boola, Gippsland, but constitutes up to 14% of the palynomorph assemblage in Albian strata. This indicates that the family was locally abundant in cool southern high-latitude climates of the Mesozoic, contrary to previous reports of its rarity in this region. [ABSTRACT FROM AUTHOR]

Abstract: Heterophyllous coniferous genera belonging to the family Cheirolepidiaceae are not always easily distinguished from one another morphologically. The taxonomically controversial genus Suturovagina from the Cretaceous of East China was studied by ultra-thin sectioning and examination under scanning and transmission electron microscopes. A detailed comparison between this genus and Pseudofrenelopsis was made based on cuticle micro- and ultrastructure as well as gross morphology. Suturovagina intermedia is among the few fossil coniferous plants for which cuticle and stomatal structures have been examined using both scanning and transmission electron microscopes and reconstructed using statistical data. Despite a slight overlap in gross morphology of leafy shoot , Suturovagina intermedia is well distinguished from Pseudofrenelopsis and all other cheirolepidiaceous conifers in cuticle and stomata micro- and ultrastructure, especially in the very deep stomatal chamber composed of tiers of subsidiary cells. The characteristic stomatal structure and the extremely thick cuticle with a wavy polylamellate layer in the cuticle proper also provide additional evidence for an xerothermic environment for the plant-bearing formation. The informative results of this study suggest that the potential taxonomic and palaeoecological significance of these features should not be neglected. [Copyright &y& Elsevier]

Although fossil conifer wood, leaves, and pollen have been known from the Upper Jurassic Morrison Formation of the Western Interior of North America for many decades, only a few conifer seed cones have been described as carbonaceous compressions and casts with little internal structure. Recently, however, over 60 silicified seed cones with preserved internal anatomy were amassed by collectors from 11 localities in northeastern and southern Utah and brought to the attention of palaeobotanists. Here we describe the silicified cones from Utah and compare them to one another in size, gross morphology and internal construction. The fossil material is sorted into five new morphotypes of seed cone. Morphotype 1 pertains to Araucariaceae, Morphotype 2 is most likely Pinaceae, and Morphotype 5 is Cheirolepidiaceae. The familial affinity of Morphotypes 3 and 4 cannot be determined at this time. Comparative size analysis based on volume calculations shows that Morphotypes 2, 3, 4 and 5 are extremely small, smaller than any Mesozoic araucarian seed cone, and that Morphotype 1 falls within the range of small fossil araucarian cones. Most cone-bearing localities are situated to the northwest, west, and south of Hanksville in southcentral Utah. With regard to palaeobiodiversity, if Araucaria delevoryasii Gee from Wyoming is included, there are now six morphotypes of seed cones that represent at least three conifer families in Utah and Wyoming. Because many conifers are arborescent and form forests, the new fossil evidence suggests that species-diverse conifer forests or woodlands were a major type of vegetation in the Morrison Formation during the Late Jurassic. [ABSTRACT FROM AUTHOR]

Shoots of cheirolepidiaceous conifers assigned to the fossil genus Frenelopsis are very common in Portuguese Early Cretaceous mesofossil floras. In this study, a new cheirolepidiaceous conifer Frenelopsis antunesii is described from the Lower Cretaceous (upper Aptian –lower Albian) of Figueira da Foz Formation at the Carregueira site, close to the small village of Juncal, in western-central mainland Portugal. The new fossil conifer is described based on morphological characters of vegetative shoots and cuticular features. The new species, Frenelopsis antunesii , is characterised by branching segmented shoots with three leaves per node, leaf surfaces distinctly covered by trichomes, leaves with thick cuticles and stomata arranged in short rows. The stomatal apparatus is composed of four or rarely five subsidiary cells. The morphological and anatomical features documented here support the view that Frenelopsis antunesii likely grew in a semiarid to arid climate. • A new cheirolepidiaceous conifer is described from the Lower Cretaceous of Portugal. • Frenelopsis antunesii sp. nov. shows segmented shoots with three leaves per node. • The new species adds new information on the morphological variation in frenelopsids. • Supports the importance of the cheirolepidiaceous conifers in the Cretaceous floras. [ABSTRACT FROM AUTHOR]

Abstract: Plant macrofossils with epidermal features from the Lower Albian (Lower Cretaceous) Plattenkalk 2 as exposed in “Le Cavere” quarry within Pietraroja Fossil-Lagerstätte, southern Italy, include sterile foliage-bearing shoots and reproductive structures of gymnosperms and possible angiosperm leaves occurring in a controversial marine depositional environment. The following taxa are recorded: Brachyphyllum sp., Frenelopsis sp., Cheirolepidiaceae gen. et sp. indet. and Nageiopsis?. Bituminous strata of the lower Plattenkalk 2 are full of plant debris composed mainly of isolated leaves and sterile axes. Taphonomic considerations suggest parautochtonous deposition for Frenelopsis while the other plant remains are allochthonous. Among the plants studied, the cheirolepidiaceous conifers have ecological significance owing to their (debated) xeromorphic foliar features. These adaptations suggest a warm and dry, or possibly coastal palaeoenvironment. Studied plant fossils together with sedimentological and palaeozoological considerations do not exclude a lagoonal hypothesis for Pietraroja sedimentary basin. This research expands the phytotaxonomic knowledge of the emergent lands within the Early Cretaceous Apenninic Carbonate Platform (ACP). [Copyright &y& Elsevier]

The discovery of 16 cylindrical conifer seed cones at the Estancia Vilán locality in the Late Jurassic Cañadön Calcáreo Formation of Chubut Province, Patagonia, Argentina, provides anatomically preserved specimens, allowing for the description of a second species of Pararaucaria (Cheirolepidiaceae). The new species, Pararaucaria delfueyoi, is similar in general features to the type species, Pararaucaria patagonica, but has a specifically diagnostic combination of characters that include cone size, seed number, features of histology, and seed size. Specimens are cylindrical with a narrow axis that bears helically arranged bract/scale complexes. The bract and scale diverge from the axis at ~90° and separate from each other almost immediately. The ovuliferous scale extends toward the margin of the cone and then arches over to enclose two inverted nonwinged seeds within a pocket of tissue. Although the specimens are abraded such that the distal regions of the ovuliferous scales are not preserved, this combination of morphological and histological characters allows for the assignment of P. delfueyoi to the Cheirolepidiaceae with confidence. The co-occurrence of this cone with an undescribed species of Araucaria extends the geographic and stratigraphic ranges of this association, which previously has been known only from the Middle Jurassic of Santa Cruz Province of Patagonia. This extends the knowledge of anatomical variation among seed cones of Cheirolepidiaceae and improves our understanding of homology relationships for conifer seed cone structures. [ABSTRACT FROM AUTHOR]

A cylindrical permineralized conifer seed cone has been identified from the Officer Member of the Trowbridge Formation, near Izee, in east-central Oregon. The cone is preserved in a Middle Jurassic (Callovian) marine calcium carbonate concretion, associated with araucarian seed cones, conifer twigs and wood, cycad seeds, fern rachides, and lycopodialean remains and was prepared by the cellulose acetate peel technique. The specimen is abraded, 2.8 cm long and 1.3 cm wide, and consists of a cone axis with helically arranged bract/scale complexes, with a large ovuliferous scale and a broad, flattened bract. The bract/scale trace arises as a cylindrical unit from the cone axis, in which the bract and scale traces are separated by ground tissue. The traces separate immediately in the cortex to form a crescent-shaped bract trace and a horseshoe-shaped scale trace with associated sclerenchyma bands that form two triangular bundles toward the distal end of the scale. Ovuliferous scale tissue covers one inverted seed per scale, forming a pocket that contains the seed. Seeds are attached at the chalaza to the inside of the pocket. Seed integuments have an outer epidermis of isodiametric cells with dark contents; one or two layers of palisade cells, occasionally appearing in I-beam configuration; and several inner layers of randomly arranged cells. The nucellus is adnate to the integument, to near the apex, where it forms a cellular mound of tissue. Cylindrical cones with helically arranged bract/scale complexes, bract and scale free to the base, one seed per scale enclosed in a pocket, and triangular sclerenchyma bands are characteristic of the genus Vararaucaria, which recently has been placed in the extinct conifer family Cheirolepidiaceae. This third species extends the known range of Pararaucaria from the Southern Hemisphere to the Northern Hemisphere and emphasizes that the association of araucarian and pararaucarian conifers extended over a wide geographic area during the Jurassic. [ABSTRACT FROM AUTHOR]

A large number of cheirolepidiaceous shoots and some associated male and female cones collected from the Lower Cretaceous Youngdong Group in the Youngdong area of Chungcheongbug-do, Korea, are described as Pseudofrenelopsis cf. parceramosa (Fontaine) Watson, its male cone of Classostrobus comptonensis Alvin et al. and female cone based on their external morphology respectively. The abundant presence of Pseudofrenelopsis shoots in the Youngdong Group indicates that it was a dominat group flourished during the Early Cretaceous in Korea. [ABSTRACT FROM AUTHOR]

Nearly all data regarding land-plant turnover across the Cretaceous/Paleogene boundary come from western North America, relatively close to the Chicxulub, Mexico impact site. Here, we present a palynological analysis of a section in Patagonia that shows a marked fall in diversity and abundance of nearly all plant groups across the K/Pg interval. Minimum diversity occurs during the earliest Danian, but only a few palynomorphs show true extinctions. The low extinction rate is similar to previous observations from New Zealand. The differing responses between the Southern and Northern hemispheres could be related to the attenuation of damage with increased distance from the impact site, to hemispheric differences in extinction severity, or to both effects. Legacy effects of the terminal Cretaceous event also provide a plausible, partial explanation for the fact that Paleocene and Eocene macrofloras from Patagonia are among the most diverse known globally. Also of great interest, earliest Danian assemblages are dominated by the gymnosperm palynomorphs Classopollis of the extinct Mesozoic conifer family Cheirolepidiaceae. The expansion of Classopollis after the boundary in Patagonia is another example of typically Mesozoic plant lineages surviving into the Cenozoic in southern Gondwanan areas, and this greatly supports previous hypotheses of high latitude southern regions as biodiversity refugia during the end-Cretaceous global crisis. [ABSTRACT FROM AUTHOR]