Sterile Foliage Research Articles

Kimuriella gen. nov. (Bennettitales), a Whole-Plant Bennettite from the Oxfordian (Upper Jurassic) Tochikubo Formation of Shidazawa, Minamisōma, Fukushima Prefecture, Northeast Japan

A new whole-plant bennettite—Kimuriella densifolia—is described and restored based on excellently preserved fossils from the Oxfordian (Upper Jurassic) Tochikubo Formation of Northeast Japan. Recent excavations revealed plant fossils with axes, sterile foliage and ovuliferous Williamsonia type flowers in organic connection. The sterile foliage of the plant is identical to what is described as Zamites nipponicus when found isolated. Microsporangiate flowers of the Weltrichia type were preserved together with the articulated macrofossils and conspecificity is strongly warranted. The absence of an appropriate plant genus to accommodate the restored plant based on the articulated fossils necessitated the erection of the new genus Kimuriella for whole-plant bennettites with a divaricate growth habit and Zamites type foliage. Kimuriella densifolia is compared with a number of coeval bennettites, amongst which the very similar Williamsonia gigas and Williamsonia pecten from the Bajocian of Yorkshire, UK. Nomenclatural issues of the latter two bennettite species are discussed in detail when research on the different organs assigned to them raised some questions connected with the classical circumscription of the taxa complying with the concept of form-classification of fossil plant organs. Finally, some interpretations of the coastal/river delta environment and habitat, in which Kimuriella densifolia thrived, are discussed.

Reanalysis of putative ovarian follicles suggests that Early Cretaceous birds were feeding not breeding

We address the identity of putative ovarian follicles in Early Cretaceous bird fossils from the Jehol Biota (China), whose identification has previously been challenged. For the first time, we present a link to the botanical fossil record, showing that the “follicles” of some enantiornithine fossils resemble plant propagules from the Jehol Biota, which belong to Carpolithes multiseminalis. The botanical affinities of this “form-taxon” are currently unresolved, but we note that C. multiseminalis propagules resemble propagules associated with cone-like organs described as Strobilites taxusoides, which in turn are possibly associated with sterile foliage allocated to Liaoningcladus. Laser-Stimulated Fluorescence imaging furthermore reveals different intensities of fluorescence of “follicles” associated with a skeleton of the confuciusornithid Eoconfuciusornis zhengi, with a non-fluorescent circular micro-pattern indicating carbonaceous (or originally carbonaceous) matter. This is inconsistent with the interpretation of these structures as ovarian follicles. We therefore reaffirm that the “follicles” represent ingested food items, and even though the exact nature of the Eoconfuciusornis stomach contents remains elusive, at least some enantiornithines ingested plant propagules.

On the nomenclature of the fossil‐genera Acitheca, Bifariusotheca, Polymorphopteris and Strephopteris (fossil Pteridophyta, Marattiopsida)

AbstractThe complicated nomenclatural history of the extinct fossil‐genera Acitheca and Strephopteris (fertile foliage) and Polymorphopteris (sterile foliage), established for fossil ferns (Marattiopsida), is reviewed and corrected with new bibliographic and historical data. Strephopteris as a generic name established for fertile foliage of Acitheca‐type has priority, but due to the long and widespread use of Acitheca it was recently proposed to reject it in favour of the established name Acitheca. Since Acitheca as a fossil‐genus was established for distinctive fertile foliage, but its currently accepted type, A. polymorpha (≡ Pecopteris polymorpha), was founded on sterile foliage, it is proposed to reject this type and return to the earlier concept of Sterzel who thought that Acitheca was typified by the fossil‐species Scolecopteris conspicua, based on fertile foliage. This procedure requires official conservation of the type. Correction of the type allows continuing the current use of another fossil‐genus, Polymorphopteris, which was inadvertently validated on the same type as Acitheca. The legitimization of the fossil‐genus Polymorphopteris, based on sterile foliage only, will stabilize the current established systematics of fossil marattiopsid remains, for which no fertile organs are known. Since Scolecopteris conspicua, when established as a fertile counterpart of sterile foliage known as Pecopteris polymorpha, originally included two unrelated archetypes of fertile foliage, known as compressions and petrifactions, the typification of the fossil‐species by fossil specimens known as compressions allows continued use of Acitheca as a distinct fossil‐genus for fertile foliage as compressions. The petrifactions formerly attributed to A. polymorpha from younger sediments (Lower Permian) of France are re‐considered as a distinct fossil‐species, Scolecopteris renaultii sp. nov. The formerly not validly published fossil‐genus Bifariusotheca for Acitheca‐like fossils from the Permian of China is validated. Kamatheca is validated for the aberrant Angaridan fossil‐species, Acitheca gigantea. Nine not validly published fossil‐species of Polymorphopteris are validated to follow modern circumscription of the fossil‐genus: Polymorphopteris cistii comb. nov., P. gothanii comb. nov., P. integra comb. nov., P. magdalenae sp. nov., P. multifurcata comb. nov., P. oblongifolia comb. nov., P. pseudobucklandii comb. nov., P. pseudointegra comb. nov., and P. wagneri sp. nov. Callipteridium subelegans and Scolecopteris conspicua are neotypified; Acitheca isomorpha and Pecopteris cistii are lectotypified. As an addition to Taxonomic literature II records, the precise dates of publication of the taxonomic works of Germar's Versteinerungen (1844–1853) and Schimper & Schenk's Palaeophytologie (1879–1890) are established for the first time.

A silicified Todea trunk (Osmundaceae) from the Eocene of Patagonia

The Osmundaceae family is the sister group to all other extant leptosporangiate ferns. Its rich fossil record has enabled detailed reconstructions of the evolutionary history of the group. Fossil evidence for today’s Southern Hemisphere subtribe Todeinae, however, has been difficult to accumulate, with only two unambiguous fossil occurrences of modern Todea. Here, we describe a silicified Todea stem from the Eocene Laguna del Hunco lagerstatte of Patagonia. The stem contains a heterogeneous outer cortex with distinct fibrous rings surrounding the leaf traces, indicative of subtribe Todeinae; nests of thick-walled fibres associated with departing leaf traces together with the sclerenchymatous pith and with abundant sclerenchyma fibres in the inner stipe cortex enable assignment to Todea. The stem differs from T. tidwellii—the only other known fossil Todea stem described thus far—mainly in lacking sclerenchyma lining the adaxial concavity of the stipe bundle. Co-occurrence with sterile foliage fragments indicates that the stem may belong to Todea amissa, a species that was initially described based on frond compressions from the same deposits. Our finding corroborates the widely disjunct Gondwanan distribution of Todea across the Southern Hemisphere in the past, and provides an impetus to re-assess genetic divergence between the relictual African and Australasian populations of Todea barbara today in order to resolve the evolutionary history of the group more clearly. Finally, this first report of structurally preserved plant remains from Laguna del Hunco highlights the thus far untapped potential for anatomical preservation in this important fossil lagerstatte.

How diverse were ferns in the Baltic amber forest?

AbstractDiverse temperate forest types and a high atmospheric humidity have recently been suggested for the Eocene source area of Baltic amber. However, ferns are astonishingly rare as inclusions in this amber, which is in contrast to other seed‐free land plants, fungi, and lichens. Moreover, the identities of some of the few described putative fern taxa are dubious, and some fossils were even assigned to the Paleozoic seed fern genera Alethopteris, Pecopteris and to the form genus Sphenopteris containing Paleozoic and Mesozoic fern‐like leaf fossils. Here, we review previously described fern inclusions from Baltic amber and identify further fern‐like leaf inclusions as belonging to the extant angiosperm genus Comptonia (sweet ferns, Myricaceae). We conclude that only one taxon, Matonia striata (Matoniaceae), can with confidence be identified as a Polypodiopsida representative. Although “Pecopteris” humboldtiana is so far only known as sterile foliage, its leaf morphology strongly suggests that also this taxon belongs to the Polypodiopsida rather than to any other tracheophyte lineage. We propose accommodating “Pecopteris” humboldtiana in the new genus Berendtiopteris. “Alethopteris” serrata and “Sphenopteris” phyllocladoides are not to be regarded as evidence of ferns from Baltic amber. Reinvestigation of the holotypes of these two taxa did not reveal to which tracheophyte lineages these fossils belong. We suggest that the scarcity of fern remains from Baltic amber may reflect both a relatively low fern diversity in the source area of the fossil resin, and an absence or rarity of epiphytic and climbing ferns as observed in modern temperate forest ecosystems.

The cycadalean megasporophyll Dioonitocarpidium in the Carnian (Late Triassic) flora of Lunz am See, Austria

Twenty-seven specimens from the Carnian flora of Lunz am See, Austria, belonging to Dioonitocarpidium, a genus to accommodate cycadalean megasporophylls, have been examined. In agreement with older reports, two clearly separable species have been identified, viz. Dioonitocarpidium titzei (Krasser 1917) Pott, comb. nov., and Dioonitocarpidium liliensternii Krausel 1953, emend. Pott. Both species required a revision after examination of the original specimens and the related bibliography. For the first time, epidermal anatomy is described for a Dioonitocarpidium species from cuticle remains. The sterile foliage of the Dioonitocarpidium parent plant is discussed and giant cycad-like foliage assigned to Nilssonia is identified as the most plausible option. The putative assignment of the Dioonitocarpidium megasporophylls to the Cycadales is also discussed.

Lunzia austriaca – a bennettitalean microsporangiate structure with Cycadopites-like in situ pollen from the Carnian (Upper Triassic) of Lunz, Austria

Based on new evidence obtained from freshly collected fossils, we here provide an emendation of Lunzia and Lunzia austriaca with an updated interpretation of the organ architecture, function and affiliation. The specimens reveal that Lunzia austriaca is a pollen organ resembling structures assigned to Weltrichia. Lunzia austriaca comprises cup-shaped pollen organs that develop up to about ten, basally fused lobes carrying appendices. The appendices are arranged pairwise and inserted laterally to a rachis-like structure, in a pinnate architecture on their adaxial side and are interpreted as prominent segments or fertile pinnae that bear numerous synangia identifying them as microsporophylls. The nature of the rachis-like structure is not straightforward. The rachis-like structure could either be fused with a bract – this fused structure then constituting the lobes – or itself been modified depicting a foliate appearance. The microsporophylls are narrow at the base and involute apically or with a sterile apical cowl. Numerous synangia with contracted bases are arranged on the inner (adaxial) side of the microsporophylls in long rows. The synangia consist of presumably four pollen sacs (microsporangia), are oblong and dehisce longitudinally. The pollen is monosulcate, elliptical and with a smooth exine (psilate). It is identified as Monocolpopollenites (=Cycadopites); from the size range, it fits best into Cycadopites accerimus. The architecture and the epidermal anatomy of Lunzia austriaca is discussed and its structure is compared with several contemporary bennettitaleans; sterile foliage and ovulate structures most likely associated with Lunzia austriaca are Pterophyllum filicoides and Westersheimia pramelreuthensis, respectively.

Bennettitales in the Rhaetian flora of Wüstenwelsberg, Bavaria, Germany

The diverse bennettitalean plant remains from the Rhaetian of Wüstenwelsberg, Franconia, southern Germany, are described by means of macromorphological and epidermal anatomy; the study is part of the ongoing examination of this recently excavated and excellently preserved fossil flora. The taxa identified include four species of Pterophyllum, one species of Anomozamites, two species of Nilssoniopteris and one species of Wielandiella with sterile leaves, bracts and ovulate reproductive organs. In addition, an enigmatic type of bennettitalean microsporangiate organ has been obtained, remains of which from the Rhaetian of Greenland had been assigned to Bennettistemon. However, the material from Wüstenwelsberg is much more complete and is assigned to a new genus, viz. Welsbergia gen. nov., with its type species Welsbergia bursigera (Harris) comb. nov., based on the organ's unique architecture. The microsporangiate organs are always exclusively associated with the sterile foliage Pterophyllum aequale. Comparison of the flora from Wüstenwelsberg with adjacent Rhaetian floras revealed distinct local differences in the bennettitalean constitution, which are discussed in the light of palaeogeography and plant dispersal patterns.

A diverse fern flora including macrofossils with in situ spores from the late Eocene of southern New Zealand

Three types of fossil fern fronds bearing sporangia with in situ spores are described from the late Eocene Pikopiko Fossil Forest, southern New Zealand. They are referable to the extant fern genus Thelypteris subgenus Cyclosorus (Thelypteridaceae) and an extinct fern of uncertain affinity. The matching of Thelypteris (Cyclosorus) macrofossils to the spore form taxon Laevigatosporites ovatus is recognised for the first time. Five additional fern taxa, including another probable Blechnum, are distinguished on the basis of sterile foliage. The Pikopiko site is one of the richest known Cenozoic fern floras globally and the diversity and abundance of ferns (eight fern macrofossil parataxa and 20 miospore types) implies that ferns dominated the evergreen, tall forest understorey as in modern New Zealand rainforests. At least 40% of modern New Zealand fern families are represented in this 35Ma flora and the discovery of fronds with in situ spores of a type recorded throughout the Cenozoic in New Zealand supports a long history for some fern genera in the region. The abundance of ferns, epiphyllous fungi on many leaves and the presence of palms is evidence for warm humid conditions in Late Eocene New Zealand.

Новый вид рода Peltaspermopsis Gomankov из верхней Перми Субангариды

Impressions of the peltaspemous female fructifications from the Novy Kuvak locality (the Kazanian of the Samara Region, Russia) are described as Peltaspermopsis nebritovii sp. nov. They represent racemose fertile shoots about 7 cm in length and 3 cm in width bearing peltate simple polysperms (peltoids). Peltoids are radially symmetrical, 10—15 mm in diameter and bear about 20 radial grooves at their upper surfaces. The margin of the seed-bearing disc is lobed and turned down to the adaxial side. About 20 relatively small and round seed scars are located at the lower surface of the seed-bearing disc around the stalk, by which it is attached to the main axis of the fructification. The length of the stalk is 5 to 10 mm. The main difference of the described fructifications from the other species of Peltaspermopsis consists in their racemose organization broading by that the diagnosis of the genus. The new species is compared with many racemose peltaspermous fructifications described previously from the Permian of the Russian Platform and the Pechora Basin, none of which has nevertheless been assigned to Peltaspermopsis. It is likely that the plants with such fructifications produced sterile foliage assignable to Compsopteris.

Ditaxocladus (extinct Cupressaceae, Cupressoideae) from the Upper Cretaceous and Paleocene of the Northern Hemisphere

An emended diagnosis of the extinct cupressoid genus Ditaxocladus S. X. GUO & Z. H. SUN (syn. Fokieniopsis MCIVER & BASINGER) and its three species is proposed based on new collections from the type locality in the Paleocene Wulonggu Formation of Altai in NW China, and other sites from China, SE Russia and western North America. Ditaxocladus planiphyllus S. X. GUO & Z. H. SUN (generitype) is now known from compound racemose fertile branches bearing several opposite pairs of globose to sub-globose seed cones composed of 6-12 decussate peltate scales, in addition to typically oppositely branched sprays. Besides D. planiphyllus, two more species are recognized based on differences in seed cone morphology. D. kivdensis KODRUL in KRASSILOV et al. from the Paleocene of Raichikha in Amur Province, Russia, is distinguished by similar but slender and pendulous cones, while D. catenulatus (W. A. BELL) S. X. GUO, KVACEK, MANCHESTER & Z. K. ZHOU comb. n. (syn. Fokieniopsis catenulata (W. A. BELL) MCIVER & BASINGER and Fokienia ravenscragensis MCIVER & BASINGER) typified by early Paleocene records in North America bears ovoid seed cones with a higher number of cone scales. All three species share the same type of bipinnately and oppositely ramified elongate sprays of cladode-like foliage and pinnately and oppositely arranged seed cones at successive nodes on compound racemose fertile branches. They differ from the living Fokienia, with which they were formerly compared, in oppositely (vs. alternately) branched leafy sprays and oppositely clustered (vs. solitary) seed cones consisting of much fewer cone scales (6-12 vs. 12-18 in Fokienia). Sterile foliage attributed to Ditaxocladus occurs in the Upper Cretaceous to Paleocene of North America, Russia and Paleocene of Spitsbergen. Tracing differentiation of Ditaxocladus populations (or species) over the Northern Hemisphere is hampered by incompleteness of most records based on quite uniform foliage without seed cones. Tetraclinis salicornioides (UNGER) KVACEK from the Eocene to Pliocene of Europe and the Oligocene to Miocene of North America, which shares very similar gross morphology of foliage, differs from Ditaxocladus in the quadrivalvate seed cones and papillate leaf epidermis with undulate anticlinal walls.

Revision of the genus Cunninghamites (fossil conifers), with special reference to nomenclature, taxonomy and geological age

The genus Cunninghamites was originally described for fossil sterile foliage. The inclusion of fertile material, and the debate about the nomenclature and taxonomy of Cunninghamites have initiated its revision. Revision has shown that only six species undoubtedly belong to Cunninghamites. Ovuliferous cones of Cunninghamites oxycedrus and Cunninghamites squamosus have been added to the diagnoses of these species. Based on the ovuliferous cones, Cunninghamites belongs to the Cupressaceae s.l.After revision of Cunninghamites, it can geographically be confined to the Northern Hemisphere, mainly Europe and North America. The stratigraphic range of the genus now starts at the Valanginian–Hauterivian and can be extended upwards to the Maastrichtian.

An Early Cretaceous flora from Cusano Mutri, Benevento, southern Italy

A new Early Cretaceous, late Aptian plant assemblage collected near the village of Cusano Mutri in the southern Apennines (Campania, Italy) is examined. The fossils consist mainly of impressions and compressions of sterile foliage shoots and reproductive structures of conifers, and a few angiosperm leaves. Cuticular analyses are provided. The genera Cupressinocladus, Pagiophyllum, Araucarites, Frenelopsis and Montsechia are documented. The occurrence of Montsechia vidalii outside of Spain is recorded for the first time. A description of a new cheirolepidiacean species, Frenelopsis cusanensis is supplied and macroscopical and cuticular characters as seen under light and scanning electron microscopes are given. Xeromorphic features displayed by almost all taxa suggest semi-arid or arid conditions in a subtropical or tropical climate. The floral assemblage displays a strong affinity with the Euro-Sinian Province of the Northern Hemisphere, which is confirmed by the absence of typical Gondwanan representatives. The discovery of this new late Aptian flora in the Apenninic Carbonate Platform domain and its palaeoecological significance provide new insights into the relationships between the platform and the mainland within the Early Cretaceous Tethyan realm.

Taxonomic revision of the Palaeozoic marattialean fern Acitheca Schimper

The Pennsylvanian genus Acitheca Schimper, 1879 is revised based on re-examination of the sterile types, plus evidence from well-preserved fertile and sterile material from Canada and the Czech Republic ( n = 750 specimens). Acitheca was an arborescent marattialean fern about 3.5 m high with large, tripinnate or quadripinnate fronds which produced Caulopteris-like frond scars on the trunk. Although its reproductive structures are similar to those of Asterotheca Presl, Acitheca differs in a number of characters of the sterile foliage (especially the venation), and its palynology. The veins fork at least twice (except in the smallest pinnules): after the first dichotomy, the upper branch divides and then the lower branch divides, producing polymorphopterid veining pattern. Synangia occur in two rows, one on either side of the midvein, and usually consist of four elongate sporangia that extend beyond the pinnule margin. Recovered in situ spores show a much greater ontogenetic variability than any other known Pennsylvanian marattialean; the size varies from 34 μm to 116 μm, and exine ornamentation from laevigate (immature spores), finely microgranulate to scabrate (intermediate spores), to microverrucate–microgranulate (mature spores). Three species are described in the paper: Acitheca polymorpha (Brongniart) Schimper, Acitheca ambigua (Sternberg) Němejc, and a new species Acitheca alii sp. nov. Distributional evidence suggests that Acitheca probably originated in eastern North America and Western Europe in middle Pennsylvanian, and towards the end of it its geographical range had extended to Eastern Europe, the Caucasus, and into Permian of China.

Functional groups of fossil marattialeans: chemotaxonomic implications for Pennsylvanian tree ferns and pteridophylls

Marattialean-fossil foliage, assigned to Pecopteris Brongniart, was an important and widespread floral component in Late Pennsylvanian mires, with phylogenetic affinity to extant marattialean taxa in tropical regions. Marattialean fossil taxonomy is, however, still uncertain. Specimens from the Pilsen limnic Basin, Westphalian D, Czech Republic, represent fertile marattialean foliage of Pecopteris ( Asterotheca) nyranensis and Pecopteris ( Asterotheca) miltonii, and sterile foliage of Pecopteris aspidioides and Pecopteris polypodioides. Taxonomic parameters for their assignments included cuticle, stomatal morphologies (studied for the first time), and in situ reproductive organs and spores. Chemotaxonomic interpretations hinge on fidelity of preservation of compounds, or molecular fragments thereof, that were synthesized by the once-living plants. This preservation state was possibly due to the thermal history (maximum temperature of 130 °C) in the Pilsen Basin, acidic preservation conditions, lithology and facies stability. Although subtle, the four pecopterid species are differentiable from one another by combined FTIR characteristics, supporting taxonomy. The ratio of CH 2/CH 3 is hypothesized to be a chemotaxonomic parameter for Pennsylvanian pteridophylls, both in seed and true ferns that have previously been studied. It will, however, be supplemented by additional biochemical markers.

Cretaceous (Late Albian) coniferales of Alexander Island, Antarctica. 2. Leaves, reproductive structures and roots

Coniferous foliage from the Albian of Alexander Island, Antarctica, is assigned to the Araucariaceae, Podocarpaceae, and Taxodiaceae based on attached or associated fertile remains. Araucarian foliage represented by Araucaria alexandrensis sp. nov. and A. chambersii sp. nov. is associated with ovulate cone scales described as Araucarites wollemiaformis sp. nov. and A. citadelbastionensis sp. nov., respectively. The Podocarpaceae is represented by Bellingshausium willeyii sp. nov. and the Taxodiaceae by Athrotaxites ungeri, both with attached cones. Sterile foliage is widespread belonging to the form genera Podozamites, Elatocladus, Brachyphyllum and Pagiophyllum. The conifers in this Albian southern high-latitude flora make up ca. 15% of the species diversity. Evidence from leaf litter distribution on palaeosols and leaf morphology suggest that the majority of conifers were large canopy-forming trees, although a few were probably small understorey shrubs.

Possible Early Pennsylvanian Ancestor of the Cycadales

A specimen of Lesleya, previously known only as isolated sterile foliage, has been found with two rows of ovule-bearing receptacles on opposite sides of the petiole. This specimen is from the Lower Pennsylvanian (Namurian B or C) of western Illinois. The fertile portion of this specimen is similar to Phasmatocycas kansana Mamay from the Lower Permian of Kansas and Texas, which Mamay interpreted as an ancestral form to cycads. Phasmatocycas was found attached to the base of Taeniopteris by Gillespie and Pfefferkorn. The foliar portions, Lesleya and Taeniopteris, have many features in common; the major morphologic difference is curvature of the veins. Lesleya and its attached fertile petiole are proposed as ancestors of Taeniopteris and Phasmatocycas, and ultimately, the ancestors of modern cycads. This extends the age of known precursors of cycads back from the Early Permian to Early Pennsylvanian (about 320 million years ago), approximately 35 million years earlier.

Aspects of Permian palaeobotany and palynology. XI. On the recognition of true peltasperms in the Upper Permian of Western and Central Europe and a reclassification of species formerly included in Peltaspermum Harris

Foliage and ovuliferous organs of a Late Permian representative of the family Peltaspermaceae are described and discussed. The sterile foliage belongs to the well known species Lepidopteris (al. Callipteris) martinsii (Germar) Townrow. Correlated ovuliferous organs consist of radially symmetrical peltate discs, assign able to the form-genus Peltaspermum Harris. In this study emphasis has been given to the recognition of natural taxa. Detailed study of foliage correlated with the formgenus Peltaspermum has resulted in an emendation of the genus and its promotion to a natural status. The classification of species previously included in Peltaspermum is also discussed. Two other natural genera of the family Peltaspermaceae are discussed, viz. Peltaspermopsis Gomankov emend. and Meyenopteris nov. gen. Dispersed radially symmetrical ovuliferous discs of peltaspermaceous affinity, which cannot be interpreted in terms of natural taxa, are transferred to the form-genus Lopadangium Zhao. Autuniopsis nov. gen. is established as a form-genus for bilaterally symmetrical ovuliferous discs of peltaspermaceous affinity. The following combinations are formally introduced: Peltaspermum martinsii (Germar) nov. comb., P. ottonis (Göppert) nov. comb., Meyenopteris natalensis (Thomas) nov. comb., Lopadangium dafengshanense (Wang Ziq. et Wang Lix.) nov. comb. L. madygenicum (Dobruskina) nov. comb., L petchoricum (Chramova) nov. comb., L. usense (Dobruskina) nov. comb. and Autuniopsis dzungarica (Salmenova) nov. comb. The diagnosis of Peltaspermum martinsii is given and since foliage and ovuliferous organs have previously been described under various names a synonymy list is given. The frond architecture, variation in pinnule morphology and epidermal anatomy, palaeoecology and geographical distribution of Peltaspermum martinsii are discussed and the species is compared with other Late Permian callipterids.

Aspects of Permian palaeobotany and palynology. V. On the nature of Asterophyllites Dumasii zeiller, its correlation with Calamites gigas brongniart and the problem concerning its sterile foliage

On the basis of abundant material from the Waderner Gruppe (= Nahe Gruppe of Boy and Fichter, 1982; Autunian, Lower Permian) of Sobernheim (Nahe area, southwest Germany) it can be demonstrated that the presumed sterile foliage Asterophyllites dumasii Zeiller only represents the bract-bearing axes of the strobilus Calamostachys dumasii (Zeiller) Jongmans. Pith casts and outer surface of Calamites gigas Brongniart — the stem correlated with Calamostachys dumasii — are described and figured. The problem concerning the sterile foliage of Calamites gigas is discussed. It is here proposed that Annularia carinata (Gutbier) Schimper might represent the sterile foliage of Calamites gigas.

ASPECTS OF PERMIAN PALAEOBOTANY AND PALYNOLOGY

SUMMARY New material of Autunia milleryensis (Renault) Krasser, an Early Permian representative of the pteridospermous family Peltaspermaceae, is described from the Lower Permian of the Nahe area, F.G.R. Sandrewia texana Mamay appears to be a synonym of Autunia milleryensis. The new combinations Autunia thomasii and A. dzungarica are introduced. Callipteris conferta (Sternberg) Brongniart is the sterile foliage attributed to Autunia milleryensis.