THE PHYLOGENETIC POSITION OF ANEMIA COLIMENSIS

The unique leaf structure of the genus Anemia with its upright fertile basal pinnae has been interpreted as derived from the typical fern leaf with unmodified basal pinnae. Reported herein for the first time is the leaf morphology of a species, Anemia colimensis Mickel, which shows the most primitive condition known in the genus and clearly confirms the course of evolution. The fertile pinnae are but little modified in size, lamination, and posture. Although A. colimensis has characters of two subgenera, it is shown to be a primitive element in subgen. Anemiorrhiza and not a member of subgen. Coptophyllum as previously reported.     

Osmunda (Osmundaceae) from the Triassic of Antarctica: an example of evolutionary stasis

Compressed specimens of the fern Osmunda are described from the Triassic of the Allan Hills, Antarctica. The specimens consist of a once pinnate, deeply pinnatifid fertile frond as well as several sterile specimens. Six pinnae are present on the partial fertile rachis, with two sterile pinnae above four fertile pinnae. Both sterile and fertile specimens are virtually identical to the modern species Osmunda claytoniana. Entire fronds are fragmentary; the longest is 21 cm in length. Sterile pinnae are alternate and deeply pinnatifid, with slightly toothed pinnules and dichotomous venation. Fertile pinnae are 1-1.3 cm long, once pinnate, and lack vegetative lamina. Sporangia are clustered, each 300-375 um in diameter, and possess a transverse annulus 6-8 cells long; dehiscence is by a vertical slit. Fronds arise from a rhizome 4 cm long by 1 cm wide; two croziers are present on the rhizome. Two frond segments up to 6 cm long and three deeply pinnatifid pinnae are present on the uppermost part of one rachis. Pinnules are ~4 mm long and 2-3 mm wide. The presence of this Osmunda species in the Triassic demonstrates stasis of frond morphology, both fertile and vegetative, for the genus.     

SPORES OF BOTRYOPTERIS GLOBOSA AND BOTRYOPTERIS AMERICANA FROM THE PENNSYLVANIAN

A study of spores from fertile pinnae of Botryopteris from middle and upper Pennsylvanian coal balls from Iowa, Illinois, and Kansas indicates that there are two distinct species, Botryopteris globosa and B. americana. The organization and attachments of fertile pinnae and the sporangial morphology and dimorphism are identical in the two species. Data are given on fertile pinnae dimensions, attachments of six fertile pinnae, spore counts from individual sporangia, and spore morphology. The ornamentation of B. americana spores is verrucate to rugulate with verrucae fusing to a variable extent to form bars and convolute ridges; B. globosa spores are vermiculate or fossulate to densely rugulate with scattered verrucae. Comparisons are made with B. forensis and a re-interpretation of the spore forms of B. forensis is suggested.     

ARCHAEOPTERIS MACILENTA,ANATOMY AND MORPHOLOGY OF ITS FROND

The stem, rachides, and pinnae of Archaeopteris macilenta, formerly considered to be a fern of Devonian age, comprise a branch system in which the ultimate divisions heretofore referred to as pinnules are the leaves. The primary vascular system of the “frond” is a lobed siphonostele from which leaf traces arise in a spiral sequence. The anatomy of the “rachis” and of the “pinnae” is shown to be similar to that of the stem, Callixylon, which bore these “fronds.” Branching, epidermal pattern and stomates are described for the spirally arranged leaves (fertile pinnules). Attachment and dehiscence of sporangia as well as their stomates are reported. Archaeopteris is retained in the Class Progymnospermopsida which includes plants with gymnospermous anatomy and pteridophytic reproduction. It is suggested that Actinopodium, Svalbardia and Siderella are related closely to Archaeopteris and that this group of genera shows evolutionary stages in webbing of leaves and planation of branch systems. The opportunities for ontogenetic studies of the arborescent genus Archaeopteris are pointed out.     

THE FROND OF HETERANGIUM

Frond members belonging to the monostelic seed fern genus Heterangium have been found in Pennsylvanian age coal balls collected in the Illinois Basin. Petioles bear small pinnae below a dichotomy which produced a bipartite frond. Pinnules of the Sphenopteris obtusiloba type are borne on secondary pinnae. The anatomy of each pinna order and the pinnules is described.     

Some Upper Triassic species of Dipteridaceae from Japan and Borneo

Three Upper Triassic species of Dipteridaceae are described. By new finds of twisted arms and fertile pinnae Dictyophyllum japonicum Yokoyama (1891) from the Yamanoi Formation (Upper Carnic to the Lowest Noric) is transferred to Camptopterisjaponica (Yokoyama) Kon'no, comb. nov. Morphological and taxonomical relation of Dictyophyllum falcatum Naito (MS.) from the Middle Carnic formation with other genera and species is discussed with additional data of fertile pinnae. CUxthropteris meniscoides Brongn. is described from near the south-western border of Sarawak; this gives evidence of the presence of the southernmost outpost of the Dipteridaceae flora of south-eastern Asia in Borneo during the Upper Triassic Period.     

Storage ability of overwintering leaves and rhizomes in a semi-evergreen fern, <Emphasis Type="Italic">Dryopteris crassirhizoma</Emphasis> (Dryopteridaceae)

Dryopteris crassirhizoma is a rhizomatous semi-evergreen fern growing in the understory of deciduous forests. Although the top portion of the overwintering leaves began to wither in early winter, intensive senescence occurred in the spring, concurrently with new leaf development. Dry weight comparisons between organs revealed that the rhizome occupied the largest proportion of the total mass, followed by the pinnae. To assess the storage ability of overwintering leaves and the rhizome, seasonal changes in nitrogen content and the dry mass of pinnae and the rhizome were measured. Nitrogen (36.6%) was resorbed from winter-withering pinnae, but not from spring-withering pinnae. In contrast, a similar decrease in dry mass per unit area occurred between winter- and spring-withering pinnae (15%). These results indicate that overwintering leaves serve as a carbohydrate storage organ, but do not serve as a nitrogen storage organ. Nitrogen was not translocated from the rhizome during the early growing season, but translocation did occur in late summer and autumn. The dry mass of the rhizome decreased by 18.4% in spring, at the time of new leaf expansion. The amount of exported dry matter from the rhizome was threefold larger than that from senescent pinnae. Therefore, the rhizome is a major carbohydrate storage organ in this species, although overwintering leaves also act as a carbohydrate storage organ.     

Heinrichsia cheilanthoides gen. et sp. nov., a fossil fern in the family Pteridaceae (Polypodiales) from the Cretaceous amber forests of Myanmar

Divergence time estimates suggest that most clades constituting the fern family Pteridaceae (Polypodiales) were in existence by the Early Cretaceous. However, fossil evidence to corroborate this remains exceedingly rare. Burmese amber is an important source of new information on the radiation of derived fern lineages during the Cretaceous Terrestrial Revolution. This study describes Heinrichsia cheilanthoides gen. et sp. nov., a fern with suggested affinities to Pteridaceae, based on fertile foliage portions preserved in Early Cretaceous (~100 Ma) amber from Myanmar. Heinrichsia cheilanthoides is characterized by a pinnate‐pinnatifid frond that bears apical, marginal sori protected by a pseudoindusium. Sporangia are of the polypod type and contain tetrahedral‐globose, trilete spores with a striate perine. This discovery provides a new calibration point to test and refine molecular clock‐based concepts of the evolutionary history of the Pteridaceae. Heinrichsia cheilanthoides further substantiates the suggestion that the Cretaceous forests of Myanmar were home to a rich fern flora.     

Auxins of non-flowering plants. I. Occurrence of 3-indoleacetic acid and phenylacetic acid in vegetative and fertile fronds of the ostrich fern (Matteucia struthiopteris)

Gas chromatography-mass spectrometry evidence is presented for the presence of both phenylacetic acid (PAA) and 3-indoleacetic acid (IAA) in vegetative and fertile tissues of the sporophyte of the ostrich fern [ Matteucia struthiopteris (L.) Todaro]. 3-Indolepropionic acid, tryptamine and 3-indoleacetonitrile were not found in tissue extracts, although small amounts of 3-indolebutyric acid and tryptophol may have been present. PAA was present in amounts higher than those found in flowering plants, while LAA levels fall within the angiosperm range. The levels of both auxins were higher in the younger vegetative tissues than in mature vegetative or fertile pinnae. Recent evidence for the occurrence of angiosperm growth hormones in ferns is discussed.     

A new species of fern of the genus Pteris (Filicales: Pteridaceae) endemic to Costa Rica

The new fern species Pteris herrerae A. Rojas & M. Palacios, endemic to Costa Rica, is described. It differs from P. decurrens C. Presl in basal segments reduced to 1/5-1/2 of the next segment (vs. 2/3-3/4), basal pinnae not bifurcated (vs. bifurcated), pinnae apex mucronate (vs. acuminate) and segment apex undulate (vs. dentate). It differs from Pteris consanguinea in the elliptic pinnae (vs. oblong), two segments reduced on the base (vs. lack), segments entire to undulate (vs. dentate), basal pinnae without basiscopic lobes (vs. with basiscopic lobes) and segment apex entire to undulate (vs. dentate).     

Geographical variation in frond size,rootstock density,and sexual reproduction in <Emphasis Type="Italic">Matteuccia struthiopteris</Emphasis> populations in Norway

The main aim of this study was to quantify differences in the structure of dense Matteuccia struthiopteris (L) Todaro among geographically separated populations in Norway, and to relate these differences to variation in environmental variables. A stratified random sampling procedure was applied to select 4 m² quadrats restricted to populations dominated (>75% cover) by the fern. This dimorphic fern can produce three types of leaves (fronds): fertile (sporophyll) and sterile (trophophyll), and in addition also intermediate fronds. In all, 178 populations from different parts of the country were analysed, and in total 9,346 rootstocks were measured. Fifteen percent of the rootstocks were fertile, each producing from one to eight sporophylls, and 2.0% had developed intermediate fronds. Rootstocks with five or more sporophylls were mainly found in Southern Norway. Within the plots, there were major variations in density (10–112), number of small (new) ramets (0–58), total number of sporophylls (0–94) and estimated total fern wet-weight (0.33–22.8 kg). All new additions to the populations were connected to a mother plant (ramets), and none were of sexual origin (genets). The main environmental variables associated with the variation in population structure were mean July temperature (highly correlated with altitude and latitude), mean precipitation and density of the canopy cover. The density of small ramets and number of intermediate fronds increased from south to north. The latitudinal variation in sporophyll development and maximum trophophyll height was best explained by a unimodal model. There were statistically significant differences in the population structure between the eight studied geographic areas in Norway.     

Early Cretaceous Gleicheniaceae and Matoniaceae (Gleicheniales) from Alexander Island,Antarctica

The first Cretaceous representatives of Matoniaceae and Gleicheniaceae in the Antarctic are described from the Albian flora of Alexander Island. Two new species are recognized, one is assigned to Matonia, and another to the emended gleicheniaceous form-genus Gleicheniaceaephyllum. The taxonomy of fossil genera assigned to Gleicheniaceae is problematic, and as an alternative to the invalid genus Gleichenites, we propose that Microphyllopteris be utilised as a form-genus for species that have either an unknown branching pattern or pseudo-dichotomous branching without resting buds; Microphyllopteris is reserved for ferns that cannot be ascribed conclusively to Gleicheniaceae. Alternatively, Gleicheniaceaephyllum should be used for gleicheniaceous material that has a resting bud amongst two to four primary branches. Gleicheniaceaephyllum acutum sp. nov. is preserved as sterile and fertile fronds, pinnae and pinnules. The other new species, Matonia jeffersonii sp. nov., occurs as sterile and fertile pinnae and pinnules, and is aligned to Matoniaceae based on the presence of circular-oval sori with peltate indusia. The two taxa are inferred to have either a pedate or scrambling habit. These morphologies are relatively common at Alexander Island, compared to other high latitude fossil floras, and are interpreted as an adaptation to the high disturbance, polar conditions and unusual photoperiod experienced at Alexander Island during the Early Cretaceous. The theory that angiosperms caused the demise of ferns is discussed in relation to the Matoniaceae and Gleicheniaceae, and there does not appear to be association between angiosperm expansion and the decline of these two fern families.     

广西蕨类植物新记录科——光叶藤蕨科

报道了广西蕨类植物一新记录科——光叶藤蕨科.该科植物以茎圆柱形攀缘;叶二型,通常为奇数羽状;侧生羽片以关节着生于叶轴;不育叶羽片边缘具软骨质硬齿,羽片基部上侧具一腺体;叶脉细密,中肋两侧各具1行窄长网眼,向外伸出分离小脉;能育叶线形,孢子囊群密被羽片下面,无隔丝而与其他蕨类物种相区分.目前该科在广西仅记录光叶藤蕨1种,...     

AN UNUSUAL BOTRYOPTERID SPORANGIAL AGGREGATION FROM THE MIDDLE PENNSYLVANIAN OF NORTH AMERICA

A new fertile species of Botryopteris (Botryopteridaceae: Filicales) is described from four incomplete Middle Pennsylvanian specimens. Fertile pinnae of B. cratis sp. n. consist of branched frond members bearing numerous globose sporangia. Surrounding the sporangial aggregations are larger sterile frond members (0.5-1.5 mm diam). Fertile pinnae are oval in transverse section and possess an eccentrically developed cortex composed chiefly of fibers. Some frond members show the typical botryopterid xylem configuration with three protoxylem strands. Spherical sporangia are loosely aggregated on the smallest pinnae by short, broad stalks. The annulus is band-like, two cells high, and extends transversely across the lower half of the sporangium for approximately half the circumference. Spores are oval, trilete, verrucate, and covered by a thin separable layer. Sporangium morphology is like that of Botryopteris antiqua, but the spores closely resemble those of B. globosa. The new species is unlike previously described fructifications of Botryopteris in exhibiting a small pinna system which surrounds smaller pinnae bearing sporangia in an aggregation. The new form is considered to be less specialized than previously described globosoid forms because the sporangia are much less crowded. Isolated frond members, believed to belong to the new species, have a large central arm in the pinna xylem trace that resembles the Stephanian taxon B. renaultii. Small stems attached to the adaxial surface of frond members are radial, protostelic, centrarch, and have a three-zoned cortex. The inner cortical zone contains large elongate cells with distinctive layered deposits. Stems are covered with uniseriate multicellular hairs on multicellular bases. Stems compare closely with B. mucilaginosa in histological features.     

Phenology of 16 species of ferns in a subtropical forest of northeastern Taiwan

A knowledge of fern phenology promotes understanding of the biology and ecology of ferns. In this study, the phenology of 16 fern species in a subtropical broadleaf forest (N24°46′, E121°34′) in northeastern Taiwan was monitored from August 1997 to August 2001. Every fern produced both fertile and sterile leaves in each year of the study. Most fertile leaves emerged in February and March, whereas most sterile leaves emerged from May to September. Most leaves reached full expansion during April–July and died during April–August. The average life span of leaves ranged from 4.4 months to 30.3 months. In seven species, fertile leaves lived longer than sterile leaves, but this difference was significant only in Pteris wallichiana. In the other nine species, sterile leaves lived longer than fertile leaves, but the difference was significant only in Cyathea spinulosa, Plagiogyria dunnii, and Plagiogyria adanata. The ephemeral fertile leaves of the two dimorphic species died soon after releasing their spores, at only 5 months of age. However, their sterile leaves survived for over 22 months. The fertile leaves of the other 14 species remained green for almost 2 years after releasing their spores. Sterile leaves remained sterile throughout their lives. Spores matured in May–July and were released in June–August. After spore release, the sporangia detached. No leaf produced a second cohort of sori. Several phenological events, including sterile leaf emergence, leaf expansion and senescence, and spore maturation and release, were significantly positively correlated with temperature but not with precipitation, whereas the emergence of fertile leaves was weakly negatively correlated with temperature and precipitation. However, those correlations varied among different species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

INDETERMINATE GROWTH AND RAMIFICATION OF THE CLIMBING LEAVES OF LYGODIUM JAPONICUM (SCHIZAEACEAE)

Morphological and anatomical specializations of the climbing leaves (CL) of Lygodium japonicum were investigated. Examination of growth relationships between the rachis and pinnae of the circumnutating CL revealed a close relationship to the “searcher” morphology of twining shoots. The CL has resting pinna apices (leafbuds) capable of replacing a damaged leaf apex or ramifying the foliar axis. Their structure and growth is similar to the main leaf apex. CL growth is indeterminate and occurs at a steady rate. Crozier uncoiling and rachis elongation occurs by a mechanism of unequal rates of cell division and elongation. The adaptations of the CL are interpreted as specializations within the basic principles of fern leaf morphogenesis.     

柳叶蕨属（鳞毛蕨科）分类性状观察

通过查阅馆藏标本和野外观察,对柳叶蕨属(Cyrtogonellum Ching)的形态特征进行了比较和分析。研究发现,叶脉游离或网结、顶羽片的有无、羽片对数和孢子表面纹饰等4个形态特征较为稳定,可以作为属下分类的主要依据;羽片形状和羽片大小在各个大类中较为稳定,但难以区分近缘种;而植株大小易受生境条件的影响,变异较大,不能单独用作属下分种的依据。     

Deux fougères fertiles du Stéphanien du Massif Central (France)

Two fertile ferns from the Stephanian of the Massif Central (France) are described in detail. One has been found in the Blanzy basin and is assigned to Oligocarpia (Sphenopteris) leptophylla (Bunbury) nov. comb., according to the morphology of the sterile pinnae and of the fructifications. Its spores agree with the «sporae dispersae Granulatisporites parvus (Ibr.) Potonié and Kremp. The other fern has been collected in the St Etienne basin and is assigned to Senftenbergia plumosa (Artis) Radforth var. ligerensis nov. var. Its spores agree with the morphographic genus Raistrickia (S., W. and B.) Potonié and Kremp but do not look like any described species; therefore the new species name R. polymorpha nov. sp. has been given to that spore.     

A new fossil record of Thyrsopteridaceae (Cyatheales) from the mid-Cretaceous amber of Myanmar

Paleopalynology evidence and megafossil records indicated that tree fern order Cyatheales, played an important role in Mesozoic terrestrial ecosystem. Few fossil records of the family Thyrsopteridaceae have been reported so far. In the present study, we describe a distinctive fertile pinnule segment of a fern plant preserved in a mid-Cretaceous amber from Myanmar. The well-preserved fertile pinnule is identified as a new species of the extant tree fern genus Thyrsopteris (Thyrsopteridaceae): Thyrsopteris cyathindusia n. sp. It represents the second fossil species of Thyrsopteridaceae found in the mid-Cretaceous amber from Myanmar. The new species shows distinctive characteristics of the sporophyll that are considered paleoecologically/paleobiogeographically significant for evolution of the Thyrsopteridaceae.