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Types of the stomata used throughout the text. (A) polocytic, (B) copolocytic, (C) seppolocytic, (D) desmocytic, (E) codesmocytic, (F) pericytic, (G) copericytic, (H) cyclocytic , (I) actinocytic (according to Sen and De (1992) and Van Cotthem (1970); supplemented by the authors).
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Abstract Senftenbergia plumosa (Artis) is an abundant Carboniferous fern occurring in the Central and Western Bohemian Carboniferous basins of the Czech Republic. Its epidermal structures are described in detail for the first time. The abaxial cuticles are very thin. The cells are isodiametric, random, pentagonal or hexagonal in shape. Stomata occu...
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... and Anemia Swartz are especially well known (Oudemans, 1866;Hildenbrand, 1866;Strasburger, 1867;Rauter, 1870;Prantl, 1881;Kondo, 1929;Maroti, 1961;Mickel and Larsten, 1967;Van Cotthem, 1970Sen and De, 1992). The stomata of S. plumosa are shown as actinocytic or cyclocytic. Sen and De (1992) showed that the stomata of Schizaeaceae may be polocytic (Fig. 6A) (the subsidiary cell becomes U-shaped and encircles parts of the guard cells from the distal end), copolocytic (Fig. 6B) (more than one U-shaped subsidiary cells encircle parts of the guard cells from the distal end), seppolocytic (Fig. 6C) (the subsidiary cell divides by one or more anticlinal walls; the newly formed daughter cells ...
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... 1929;Maroti, 1961;Mickel and Larsten, 1967;Van Cotthem, 1970Sen and De, 1992). The stomata of S. plumosa are shown as actinocytic or cyclocytic. Sen and De (1992) showed that the stomata of Schizaeaceae may be polocytic (Fig. 6A) (the subsidiary cell becomes U-shaped and encircles parts of the guard cells from the distal end), copolocytic (Fig. 6B) (more than one U-shaped subsidiary cells encircle parts of the guard cells from the distal end), seppolocytic (Fig. 6C) (the subsidiary cell divides by one or more anticlinal walls; the newly formed daughter cells surround the proxi- mal parts of the stoma in such a way that they become almost indistinguishable in an aspect from ...
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... as actinocytic or cyclocytic. Sen and De (1992) showed that the stomata of Schizaeaceae may be polocytic (Fig. 6A) (the subsidiary cell becomes U-shaped and encircles parts of the guard cells from the distal end), copolocytic (Fig. 6B) (more than one U-shaped subsidiary cells encircle parts of the guard cells from the distal end), seppolocytic (Fig. 6C) (the subsidiary cell divides by one or more anticlinal walls; the newly formed daughter cells surround the proxi- mal parts of the stoma in such a way that they become almost indistinguishable in an aspect from epidermal cells), desmocytic (Fig. 6D) (the guard cells become completely encircled by a sub- sidiary cells; the subsidiary ...
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... one U-shaped subsidiary cells encircle parts of the guard cells from the distal end), seppolocytic (Fig. 6C) (the subsidiary cell divides by one or more anticlinal walls; the newly formed daughter cells surround the proxi- mal parts of the stoma in such a way that they become almost indistinguishable in an aspect from epidermal cells), desmocytic (Fig. 6D) (the guard cells become completely encircled by a sub- sidiary cells; the subsidiary cell and one of the guard cells or both remain connected in the distal region by one or two short anticlinal segments of cell wall), codesmocytic (Fig. 6E) (this is desmo- cytic stoma with an additional subsidiary cell), pericytic (Fig. 6F) (this is a ...
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... in such a way that they become almost indistinguishable in an aspect from epidermal cells), desmocytic (Fig. 6D) (the guard cells become completely encircled by a sub- sidiary cells; the subsidiary cell and one of the guard cells or both remain connected in the distal region by one or two short anticlinal segments of cell wall), codesmocytic (Fig. 6E) (this is desmo- cytic stoma with an additional subsidiary cell), pericytic (Fig. 6F) (this is a desmocytic stoma minus the radial link segment/segments of cell wall between the guard cells and the subsidiary cell) and copericytic (Fig. 6G) (this is a codesmo- cytic stoma without the radial connecting link be- tween the guard cells and ...
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... cells), desmocytic (Fig. 6D) (the guard cells become completely encircled by a sub- sidiary cells; the subsidiary cell and one of the guard cells or both remain connected in the distal region by one or two short anticlinal segments of cell wall), codesmocytic (Fig. 6E) (this is desmo- cytic stoma with an additional subsidiary cell), pericytic (Fig. 6F) (this is a desmocytic stoma minus the radial link segment/segments of cell wall between the guard cells and the subsidiary cell) and copericytic (Fig. 6G) (this is a codesmo- cytic stoma without the radial connecting link be- tween the guard cells and the inner subsidiary cell). Van Cotthem (1970) stated that the Schi- zaeaceae is not ...
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... remain connected in the distal region by one or two short anticlinal segments of cell wall), codesmocytic (Fig. 6E) (this is desmo- cytic stoma with an additional subsidiary cell), pericytic (Fig. 6F) (this is a desmocytic stoma minus the radial link segment/segments of cell wall between the guard cells and the subsidiary cell) and copericytic (Fig. 6G) (this is a codesmo- cytic stoma without the radial connecting link be- tween the guard cells and the inner subsidiary cell). Van Cotthem (1970) stated that the Schi- zaeaceae is not a uniform family from this point of view. The form and structure of the epidermal cells clearly di¡er, varying from long, narrow cells with almost straight ...
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... (Fig. 6I) and cyclocytic (Fig. 6H) types of stomata occur in Marattiaceae, Polypo- diaceae and Davalliaceae (Sen and De, 1992, p. 254, table 2;Van Cotthem, 1970). Very interest- ing is a comparison of Senftenbergia plumosa cu- ticles with those of the living Marattiaceae. The adaxial cuticle of S. plumosa consists of irregular, polygonal cells ...
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... (Fig. 6I) and cyclocytic (Fig. 6H) types of stomata occur in Marattiaceae, Polypo- diaceae and Davalliaceae (Sen and De, 1992, p. 254, table 2;Van Cotthem, 1970). Very interest- ing is a comparison of Senftenbergia plumosa cu- ticles with those of the living Marattiaceae. The adaxial cuticle of S. plumosa consists of irregular, polygonal cells with straight anticlinal ...
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Citations
... However, Dactylotheca clearly differs from Senftenbergia in having exannulate sporangia restricted to the marginal parts of the pinnules lobes (Table 2), and sporangia covered by the rolled lateral edges of pinnules lobes (e.g., Toula, 1888;Barthel, 2016). Bertrand, 1912, Radforth, 1939, Corsin, 1951, Remy and Remy, 1955, Laveine, 1969 Senftenbergia plumosa Apical Punctatisporites, Calamospora, Convolutispora, Apiculatisporis, Raistrickia 25-92 Remy and Remy, 1955, Bek and Pšenička, 2001, Pšenička and Bek, 2003, Laveine, 1969, Radforth, 1938, 1939 Dactylotheca evidently needs to be studied in more detail but, despite some authors suggesting that it might be the same as Senftenbergia (e.g., Zeiller, 1888;White, 1899;Radforth, 1938), our data (Table 1, Table 2) appears to confirm their separation (Table 2). ...
Adpression specimens of fertile pinnae of Senftenbergia elegans from the Corda's type collection have been studied in detail for the first time. The specimens come from the Žďárky locality near Náchod, Intra-Sudetic Basin, Duckmantian, Czech Republic. The study shows that Senftenbergia elegans has a unique type of in situ spores, different from the other Senftenbergia-like ferns, although they all belong to the Tedelaceae.
... Menurut [12], tipe stomata beberapa spesies dari genus Asplenium yang tegolong famili Aspleniaceae adalah polositik. Tipe stomata polositik yaitu tipe stomata yang dikelilingi oleh satu sel tetangga dan juga tipe stomata dengan sel tetangga berbentuk U dan mengelilingi hampir seluruh bagian sel penjaga dari ujung distal [13]. [14] juga menyatakan bahwa tipe polositik merupakan tipe stomata yang jaringan mersitem stomatanya membelah secara melengkung untuk membentuk sel tetangga dan sel penjaga. ...
The aim of this study was to identifiy the stomata morphological characters of Pteridophyta in the ​​Parangkikis Pagerwojo Waterfall area, Tulungagung. The first step of stomata observation was preparation of the abaxial leaf slice. The preparation was carried out by the replica method. Stomata character studied include types and size of stomata, the number of stomata and epidermis cells, and value of the stomatal index. The result of this study showed that stomata types of Pteridophyta were polocytic and anomocytic. Of the 15 Pteridophyta species observed, the all of stomata type were polocytic, except Selaginella which had type stomata anomocytic. Stomata oval was found in Selaginella intermedia and Phymatosorus sp., slightly oval (kidney) was found in Asplenium apogamum, Dryopteris sp., Asplenium normale, Nephrolepis bisserata, Nephrolepis davallioides, Asplenium nidus, and Pteris longipinnula sp., spherical was found in Dicranopteris linearis, Cyclosorus arida, Goniophlebium percussom, and Goniophlebium manmiense, and nonconcave was found in Coniogramme fraxinea. Stomata size affected the number of stomata. If the size of the stomata was small, the number of stomata was increasing. The highest number of stomata was found in D. linearis, which was 362, while the least number of stomata was S. intermedia, which was 18. Data on the number of stomata and epidermal cells were used to determine the stomatal index. The highest stomata index was found in D. linearis, which was 22.05% and the lowest was C. fraxinea, which was 5.44 %. Keywords: Anomocytic, Parangkikis, polocytic, Pteridophyta, stomata
... For these reasons, we are convinced that our studied taxa from Doubrava must be classified as a different genus and cannot be the result of intraspecific variability within Discopteris. The semi-apical annulus of the species described here might be compared to the apical annulus sensu lato of Senftenbergia or Pecopteris anglica (Bek and Pšenička, 2001;Pšenička and Bek, 2003;Votočková Frojdová et al., 2020). However, the new taxa here have microspores of the Leiotriletes-Granulatisporites-Apiculatisporis type distinct from the Convolutispora-Punctatisporites-Raistrickia microspores of Senftenbergia and Pecopteris anglica (Bek and Pšenička, 2001;Votočková Frojdová et al., 2020). ...
... Tedeleaceae have an apical annulus (e.g. Pšenička and Bek, 2003) that could be compared with the biseriate semi-apical annulus in Discosoropteris. Nevertheless, the reproductive organs of Tedeleaceae are distinct from Discosoropteris: 1) the annulus occupies only about 1/3 of the sporangium length; 2) the dehiscence line is narrow and composed of thin-walled cells; 3) the apical plate is composed of extremely thin-walled cells (Bek and Pšenička, 2001); 4) the sporangia are free, sometime in small clusters (2-7 sporangia), and in a submarginal position (Eggert and Taylor, 1966). ...
... Nevertheless, the reproductive organs of Tedeleaceae are distinct from Discosoropteris: 1) the annulus occupies only about 1/3 of the sporangium length; 2) the dehiscence line is narrow and composed of thin-walled cells; 3) the apical plate is composed of extremely thin-walled cells (Bek and Pšenička, 2001); 4) the sporangia are free, sometime in small clusters (2-7 sporangia), and in a submarginal position (Eggert and Taylor, 1966). The Tedeleaceae is also characterized by Rasctrickia-type microspores (Eggert and Taylor, 1966;Bek and Pšenička, 2001;Pšenička and Bek, 2003). No other features are shared beyond some sporangial similarity, although this may reflect missing data regarding Discosoropteris. ...
A new leptosporangiate fern genus, Discosoropteris, is recognized and two species circumscribed from the Duckmantian-age Kamenný Újezd locality of the Pilsen Basin, Central Bohemia based upon tripinnate fronds preserved in the Bělka tuff. The sphenopterid pinnules bear massive disc-shaped sori, either on the laterals or midvein, that contain up to 80 annulate sporangia. The trilete microspores vary from laevigate, to microgranulate, microspinate, or finely reticulate and, thus, are comparable to both Leiotriletes and Granulatisporites. This variance is deemed most likely to reflect different stages of spore maturation. The cuticle preserves anomocytic stomata on the pinnae and a dense indumentum of multicellular uniseriate trichomes on the rachis. Trichomes are also dense within the sori where they appear to approximate the utilities of an indusium, whether for limiting environmental exposure or access to herbivores. These compression fossils preserve some traces of internal anatomy, including scalariform tracheids and bundle sheath cells that show signs of puncture-feeding herbivory. The bearing stem is unknown but preservation of the fronds within the tuff suggests they were elevated on a short, upright, self-supporting axis. Comparisons are drawn with other Carboniferous taxa, particularly Discopteris; review of the complex history of these alternatives suggests Discosoropteris is best left as incertae sedis within the basal leptosporangiate ferns rather than adding to the confusion by attempting a family-level assignment at this time.
... Nevertheless, there were some true ferns growing in the coal swamps (DiMichele and Phillips, 2002). During Serpukhovian and Bashkirian times, the most abundant were climbing tedeleacean ferns with small, tongue-shaped leaflets (Pšenička and Bek, 2003) growing mainly in the clastic substrate habitats. There were also some smaller, possibly epiphytic ferns (e.g. ...
The first regional-scale forests appeared in mid-Carboniferous times, c. 325 million years ago (Ma). Known as the coal swamps, they extended over large parts of tropical Pangaea and lasted for about 40 million years. The dominant plants of the swamps were arborescent lycopsids, sphenopsids, ferns, pteridosperms and cordaitanthales. Many were very fast-growing plants and resulted in thick peat deposits being formed, which have subsequently changed into economically important coals. Changes in the geographical extent of these tropical swamps correlated with the waxing and waning of the Late Palaeozoic Ice Age polar ice sheet, and the carbon sequestration caused by the swamps may have been affecting global climates. The development of the swamps coincided with a major global diversification in insects and may also have been home to some early terrestrial amphibians and reptiles.
Key Concepts
• The coal swamps were the first regional-scale forests to occur on Earth.
• The swamps occupied a broad belt of land in palaeotropical Pangaea during the late Carboniferous and early Permian (325–275 Ma).
• They were responsible for one of the highest rates of terrestrial carbon sequestration in Earth history.
• The size of the coal swamps was correlated with climate fluctuations during the Late Palaeozoic Ice Age.
• Insects and possibly of tetrapod vertebrates diversified during the time of the coal swamps.
... The cuticle of Eremopteris has also been described (Cleal et al., 2009) and may be present in the material and distinguishing ferns from pteridosperms in the charred material may prove problematic. We know for example ferns such as Renaultia but other forms of fern-like foliage such as Zeilleria and Palmatopteris could be represented in the charred material (Plates III-XI), but few taxa have been described as regards their epidermal structure (but see Krings et al., 2003;Šimůnek and Cleal, 2002;Bek and Pšenička, 2001;Pšenička and Bek, 2003). The spore Raistrickia and other fern spores have been found in palynological preparations from Swillington (Scott, 1976(Scott, , 1978Highton et al., 1991) and indeed many of the palynodebris samples from the sediments throughout the Swillington succession contain charcoal (fusain) fragments (Highton et al., 1991). ...
New data on some fossil charcoal deposits from the British Isles is integrated into previous studies to provide an indication of our current understanding of the role of fire on land in the Pennsylvanian and also provide strategies for obtaining new information in the future.
The nature and occurrence of fossil charcoal (often called fusain) in sediments and coals (often described as inertinite/fusinite/semi-fusinite) is the main way that the history of Carboniferous fire has been studied. Fires have been shown to have been common in many Carboniferous ecosystems around the world, yet we still have little understanding of the details of what these fires were, where and how they occurred, or their effects upon both on the local ecosystem and the Earth System as a whole. Research has demonstrated that detailed scanning electron microscope studies of charcoal residues can provide data on the plants that have been charred by wildfires.
Information on the amount of charcoal in coal globally appears to relate to atmospheric oxygen composition and this shows that throughout the Carboniferous oxygen levels were as high or higher than those of the present day, suggesting that wildfires were more frequent. Interpreting the frequency of fires in different ecosystems remains fraught with difficulty and calculations within peat (coal) systems are at an early stage. The impact of fire on vegetational change as well as the relationship between fire and climate in the Carboniferous remains little studied.
A study of the inertinite (charcoal) distribution within the Low Barnsley Seam in Yorkshire, England indicates that levels remained high throughout much of the 1.8m thick coal seam. A previous palynological study of the seam has demonstrated three repeated successions of vegetational development interpreted as repeated phases of wet to dry mire development (rheotrophic swamp to ombrotrophic bog). Inertinite peaks above 20% background have indicated a minimum of 18 significant large fire events and an analysis of depositional rates suggests a fire return interval of these large fires to be 500 years or less.
A study of charcoalified vegetation from fine-grained clastic sediments from Swillington Brickworks, Yorkshire recovered from bulk maceration of the sediment, that was not evident from bedding surface examination, has demonstrated that some levels contain abundant leaf charcoal, mainly from pteridosperms, in addition to wood charcoal derived from a range of gymnosperms. The charcoalified plants are interpreted as wildfire residues mainly from surface fires that have been transported and deposited on low-lying floodplains.
... In our view they represent different stages of spore maturity, with the laevigate forms being relatively immature and the rugulate forms fully mature. A similar phenomenon was previously reported with Pecopteris plumosa (Artis) Brongniart (Bek and Pšenička, 2001;Pšenička and Bek, 2003) and also with other Pennsylvanian ferns (e.g., Pšenička et al., 2005;Zodrow et al., 2006;Frojdová et al., 2017aFrojdová et al., , 2017b. ...
... Adpressions with very similar pecopteroid pinnules, apically annulate sporangia and Convolutispora-Raistrickia spores have often been named Senftenbergia (e.g., Remy and Remy, 1955;Grauvogel-Stamm and Doubinger, 1975;Barthel, 1976). This was based mainly on observations of fertile fronds of Pecopteris penniformis and P. plumosa (e.g., Radforth, 1939;Laveine, 1969;Bek and Pšenička, 2001;Pšenička and Bek, 2003), which were generally assumed to belong to this fossilgenus (see also Zeiller, 1888, p. 207;Bertrand, 1912Bertrand, , 1934Lipiarski, 1965). Cleal (2015) had argued that as P. penniformis is also the type of Pecopteris and this pre-dated the name Senftenbergia (Cleal and Thomas, 2018), the latter is an illegitimate heterotypic synonym. ...
... Although, the holotype of P. penniformis is sterile, most authors (e.g., Radforth, 1939;Lipiarski, 1965;Laveine, 1969) also attributed to this species fertile specimens with free, oblong sporangia that have an apical annulus and Convolutispora-type in situ microspores (Remy and Remy, 1955;Laveine, 1969Laveine, , 1989aBoureau, 1970). This is very similar to Pecopteris anglica except that there were fewer (6-11) and larger Remy and Remy (1955), Bek and Pšenička (2001), Pšenička and Bek (2003), Laveine (1969), Radforth (1938Radforth ( , 1939 (0.7-1.0 mm) sporangia on each pinnule (Table 1). Brongniart (1822Brongniart ( , 1828 originally interpreted the P. penniformis pinnules as pinnatifid but Laveine (1989aLaveine ( , 1989b showed that they were pecopteroid/ linguaeform and so are also similar to P. anglica (Table 3). ...
Two compressions of fertile Myriotheca anglica Kidston pinnae from Kidston's type collection have been studied for the first time since the publication of its protologue. The specimens came from the Lower Coal Measures Formation (middle Langsettian Substage) of the Central Pennines Basin, UK. SEM observations have shown that this species has pinnules with 17–22 Pecopteris-type sporangia, with an apical annulus consisting of four to five rows of thick-walled cells and a stomium of five to seven rows of thick-walled cells. Based on this, a new combination, Pecopteris anglica (Kidston) comb. nov. is proposed. Two different stages of maturity of the in situ microspores are recognized: sculptured forms of the Convolutispora-type are interpreted as fully matured microspores; while laevigate, Punctatisporites-type spores represent relatively immature microspores.
... This feature is described from several fertile Carboniferous ferns (e.g. Pšenička et al. 2005, Pšenička & Bek 2003, 2008, Frojdová et al. 2017a, b, Zodrow et al. 2006. ...
Sturia amoena (Stur) Němejc is a Pennsylvanian adpression true fern known from the Charbonnière de Belle et Bonne (Belgium) and from the Radnice and Kladno-Rakovník basins (Czech Republic). This revision includes a detailed study of pinna and pinnule morphology, aphlebiae and reproductive organs. Interesting details of sporangia and in situ spores are described for the first time. The sporangia of Sturia amoena have an equatorial bi-triseriate annulus and yielded in situ spores of the Punctatisporites and Apiculatisporites types.
... In the artificial system of fern-like foliage "Pterido- phylla", the name Pecopteris plumosa is often used. Bek and P?eni?ka (2003) prefer using the name Senftenbergia plumosa based on its fructification. Additionally, the genus Pecopteris Brongniart usu- ally contains genera and species of the family Marattiaceae, whereas Senftenbergia belongs only to the family Tedeleaceae. ...
Gas-pipeline construction around Brandov (Czech Republic) exposed pre Quaternary strata allowing more precise understanding of the regional geology. The crystalline rocks in the basement, near the Brandov Carboniferous Relict, belong to Sayda Dome rather than to the Hora Svaté Kateřiny (Katharinaberg) Dome. The lower Carboniferous unit (Westphalian – Moscovian) is of greater extent than previously estimated. In contrast, the upper unit, which is correlated with Stephanian (Kasimovian or Gzhelian) strata, is arealy less extensive than previously estimated and is devoid of fossil remains. An anthracite seam, in the lower unit, was discovered in the “North depth” some 1–1.3 km to the North from old mining activity of the “South depth”. The seam was accompanied by a flora dominated by cordaitaleans and sphenopsids (calamitaleans), and common lycopsids and ferns. Palynomorphs were isolated from mudstones for the first time and 36 genera and 51 species of miospores could be determined. A humic clayey layer was discovered in the Quaternary deposits whose palynological age is 500 – 100 years old.
... Fossil Marattiales (e.g. Pecopteris and Seftenbergia) are stephanocytic (cyclocytic) or anomocytic (P seni cka & Bek, 2003;P seni cka et al., 2005) Development is mesoperigenous in extant taxa ( Mar oti, 1966;Pant & Khare, 1969). Mar oti (1966) described the division of the stomatal precursor cell in Marattia as either asymmetric (with the GMC the smaller daughter cell) or sometimes symmetric; the GMC is always the more distal daughter cell Polypodieae ('ferns' sensu stricto, Fig. 4b) ...
I. II. III. IV. V. VI. VII. VIII. References SUMMARY: We evaluate stomatal development in terms of its primary morphogenetic factors and place it in a phylogenetic context, including clarification of the contrasting specialist terms that are used by different sets of researchers. The genetic and structural bases for stomatal development are well conserved and increasingly well understood in extant taxa, but many phylogenetically crucial plant lineages are known only from fossils, in which it is problematic to infer development. For example, specialized lateral subsidiary cells that occur adjacent to the guard cells in some taxa can be derived either from the same cell lineage as the guard cells or from an adjacent cell file. A potentially key factor in land-plant evolution is the presence (mesogenous type) or absence (perigenous type) of at least one asymmetric division in the cell lineage leading to the guard-mother cell. However, the question whether perigenous or mesogenous development is ancestral in land plants cannot yet be answered definitively based on existing data. Establishment of 'fossil fingerprints' as developmental markers is critical for understanding the evolution of stomatal patterning. Long cell-short cell alternation in the developing leaf epidermis indicates that the stomata are derived from an asymmetric mitosis. Other potential developmental markers include nonrandom stomatal orientation and a range of variation in relative sizes of epidermal cells. Records of occasional giant stomata in fossil bennettites could indicate development of a similar type to early-divergent angiosperms.
... Nevertheless, we have been able to estimate frond shape and a minimum overall frond size for S. oregonensis by applying characteristics common to other Tedeleacean species to our measurements of the frond fragments. Although there is some variation among and within species, for segments of Tedeleacean fronds, (1) they tend to maintain a common overall shape and length : width ratio from order to order of pinnae (except pinnules) and (2) the maximum width of each order of dissection tends to approach the distance between successive attachment levels on the same side of the next-larger frond order (Kidston 1924;Radforth 1938Radforth , 1939Barthel 1976;Pšeni cka and Bek 2003; fig. 1A-1D). ...
Reexamination of fossilized plant material from the westernmost Pennsylvanian-age wetland flora in North America reveals that material of Pecopteris oregonensis Arnold represents a filicalean fern frond with annulate sporangia and anatomically preserved vascular tissues of the rachis. The frond, which is redescribed as Senftenbergia oregonensis (Arnold) Hillier et Rothwell comb. nov., is pinnately compound, with five orders of catadromous dissection, and it appears to have reached a length of 80 cm or more. The rachis displays an anchor-shaped xylem bundle, and dichotomizing aphlebiae are produced at the base of primary pinnae. The rachis, primary pinnae, and secondary pinnae have a dense covering of coarse trichomes. Secondary and tertiary pinnae display a length∶width ratio of 2.5∶1. The pecopterid pinnules measure 1.5–6 mm in length and 1.0–2.0 mm in width, with dichotomous venation, smooth-to-undulating margins, and a rounded tip. Sporangia are marginal and recurved under the abaxial pinnule surface to form two rows that are parallel to the midvein. Each sporangium has a narrow stalk, longitudinal dehiscence, and a terminal multiseriate annulus. The fern is assigned to the Tedeleaceae, and a combination of characters for distinguishing genera within the family is proposed.
