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1.
《Systematic and applied microbiology》2022,45(4):126336
Several pure cultures of alkaliphilic haloaloarchaea were enriched and isolated from hypersaline soda lakes in southwestern Siberia using amylopectin and fructans as substrates. Phylogenomic analysis placed the isolates into two distinct groups within the class Halobacteria. Four isolates forming group 1 were closely related to a recently described Natranaeroarchaeum sulfidigenes and the other three strains forming group 2 represent a novel genus-level phylogenetic lineage. All isolates are saccharolytic archaea growing with various starch-like alpha-glucans including soluble starch, amylopectin, dextrin, glycogen, pullulane and cyclodextrin. In addition, group 1 can use levan while group 2 – inulin (plant storage beta-fructans). Group 1 strains can also grow anaerobically with either glucose or maltose using elemental sulfur as the electron acceptor. Both groups are moderately alkaliphilic with a pH range for growth from 7.2 to 9.3 (optimum between 8.0–8.8) and low Mg-demanding extreme halophiles growing optimally at 4 M total Na+. The major respiratory menaquinone is MK-8:8 and the core biphytanyl lipids are dominated by archaeol (C20-C20) and a less abundant extended archaeol (C20-C25) with PG and PGP-Me as polar groups. The four isolates of group 1 are suggested to be classified into a new species as Natranaeroarchaeum aerophilus sp. nov. (type strain AArc-St1-1T = JCM 32519T). The three isolates of group 2 are proposed to form a new genus and species for which the name Natronocalculus amylovorans gen. nov., sp. nov. is suggested (type strain AArc-St2T = JCM 32475T). 相似文献
2.
Yi Cao Roger A. Chastain Emiley A. Eloe Yuichi Nogi Chiaki Kato Douglas H. Bartlett 《Applied and environmental microbiology》2014,80(1):54-60
The diversity of deep-sea high-pressure-adapted (piezophilic) microbes in isolated monoculture remains low. In this study, a novel obligately psychropiezophilic bacterium was isolated from seawater collected from the Puerto Rico Trench at a depth of ∼6,000 m. This isolate, designated YC-1, grew best in a nutrient-rich marine medium, with an optimal growth hydrostatic pressure of 50 MPa (range, 20 to 70 MPa) at 8°C. Under these conditions, the maximum growth rate was extremely slow, 0.017 h−1, and the maximum yield was 3.51 × 107 cells ml−1. Cell size and shape changed with pressure, shifting from 4.0 to 5.0 μm in length and 0.5 to 0.8 μm in width at 60 MPa to 0.8- to 1.0-μm diameter coccoid cells under 20 MPa, the minimal pressure required for growth. YC-1 is a Gram-negative, facultatively anaerobic heterotroph. Its predominant cellular fatty acids are the monounsaturated fatty acids (MUFAs) C16:1 and C18:1. Unlike many other psychropiezophiles, YC-1 does not synthesize any polyunsaturated fatty acids (PUFAs). Phylogenetic analysis placed YC-1 within the family of Oceanospirillaceae, closely related to the uncultured symbiont of the deep-sea whale bone-eating worms of the genus Osedax. In common with some other members of the Oceanospirillales, including those enriched during the Deepwater Horizon oil spill, YC-1 is capable of hydrocarbon utilization. On the basis of its characteristics, YC-1 appears to represent both a new genus and a new species, which we name Profundimonas piezophila gen. nov., sp. nov. 相似文献
3.
《Systematic and applied microbiology》2022,45(6):126361
Biological denitrification is a significant process in nitrogen biogeochemical cycle of terrestrial geothermal environments, and Thermus species have been shown to be crucial heterotrophic denitrifier in hydrothermal system. Five Gram-stain negative, aerobic and rod-shaped thermophilic bacterial strains were isolated from hot spring sediments in Tibet, China. Phylogenetic analysis based on 16S rRNA gene and whole genome sequences indicated that these isolates should be assigned to the genus Thermus and were most closely related to Thermus caldifontis YIM 73026T, and Thermus brockianus YS38T. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the five strains and the type strains of the genus Thermus were lower than the threshold values (95% and 70%, respectively) recommended for bacterial species, which clearly distinguished the five isolates from other species of the genus Thermus and indicated that they represent independent species. Colonies are circular, convex, non-transparent. Cell growth occurred at 37–80 °C (optimum, 60–65 °C), pH 6.0–8.0 (optimum, pH 7.0) and with 0–2.0% (w/v) NaCl (optimum, 0–0.5%). Denitrification genes (narG, nirK, nirS, and norB genes) detected in their genomes indicated their potential function in nitrogen metabolism. The obtained results combined with those of morphological, physiological, and chemotaxonomic characteristics, including the menaquinones, polar lipids, and cellular fatty acids showed that the isolates are proposed as representing five novel species of the genus Thermus, which are proposed as Thermus hydrothermalis sp. nov. SYSU G00291T, Thermus neutrinimicus sp. nov. SYSU G00388T, Thermus thalpophilus sp. nov. SYSU G00506T, Thermus albus sp. nov. SYSU G00608T, Thermus altitudinis sp. nov. SYSU G00630T. 相似文献
4.
Feiyu Jia Chongxi Liu Xiangjing Wang Junwei Zhao Qianfeng Liu Ji Zhang Ruixia Gao Wensheng Xiang 《Antonie van Leeuwenhoek》2013,103(2):399-408
A novel endophytic actinomycete, designated strain NEAU-J3T, was isolated from soybean root (Glycine max (L.) Merr) and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain NEAU-J3T fell within the family Micromonosporaceae. The strain was observed to form an extensively branched substrate mycelium, which carried non-motile oval spores with a smooth surface. The cell walls of strain NEAU-J3T were determined to contain meso-diaminopimelic acid and galactose, ribose and glucose were detected as whole-cell sugars. The major menaquinones were determined to be MK-9(H4) and MK-9(H6). The phospholipids detected were phosphatidylcholine and phosphatidylethanolamine. The major cellular fatty acids were determined to be C16:0, C18:1 ω9c, C18:0, C17:0, C17:1 ω7c, anteiso-C17:0, C16:1 ω7c and C15:0. The DNA G + C content was 62.5 mol%. On the basis of the morphological and chemotaxonomic characteristics, phylogenetic analysis and characteristic patterns of 16S rRNA gene signature nucleotides, strain NEAU-J3T is considered to represent a novel species of a new genus within the family Micromonosporaceae, for which the name Wangella harbinensis gen. nov., sp. nov. is proposed. The type strain of Wangella harbinensis is strain NEAU-J3T (=CGMCC 4.7039T = DSM 45747T). 相似文献
5.
Large segments of intact plants that represent a heterosporous fern have been discovered within an aquatic plant community from the Late Cretaceous St. Mary River Formation near Cardston in southern Alberta, Canada. Branching rhizomes of Hydropteris pinnata gen. et sp. nov. are 1–2 mm wide. They produce fronds at intervals of 2–12 mm and bear numerous elongated roots. Fronds, up to approximately 6 cm long, are pinnate with subopposite to alternate pinnae that exhibit anastomosing venation. Large, multisoral sporocarps occur at the junctures of the rhizome and frond rachides. Both microsporangiate massulae and megaspore complexes occur within each sporocarp. Megaspore complexes are assignable to the sporae dispersae genus Parazolla Hall. Microspores are trilete, smooth-walled, and are embedded in episporal material of the massulae. A numerical cladistic analysis indicates that the heterosporous aquatic ferns are monophyletic, and not as closely related to either schizaeaceous or hymenophyllaceous ferns as they are to some other filicaleans. Systematic revisions are proposed to reflect newly recognized cladistic relationships within the heterosporous clade, and character originations in the evolution of heterosporous aquatic ferns are evaluated. Hydropteridaceae fam. nov. is proposed, and included with Salviniaceae and Azollaceae in the Hydropteridineae subord. nov., and the Hydropteridales Willdenow. 相似文献
6.
Four yellow pigmented strains (91A-561T, 91A-576, 91A-593T, and JM-1085T) isolated from plant materials, showed 97.2–98.7 % 16S rRNA gene sequence similarities among each other and were studied in a polyphasic approach for their taxonomic allocation. Cells of all four isolates were rod-shaped and stained Gram-negative. Comparative 16S rRNA gene sequence analysis showed that the four bacteria had highest sequence similarities to Chryseobacterium formosense (97.2–98.7 %), Chryseobacterium gwangjuense (97.1–97.8 %), and Chryseobacterium defluvii (94.6–98.0 %). Sequence similarities to all other Chryseobacterium species were below 97.5 %. Fatty acid analysis of the four strains showed Chryseobacterium typical profiles consisting of major fatty acids C15:0 iso, C15:0 iso 2-OH/C16:1 ω7c, C17:1 iso ω9c, and C17:0 iso 3-OH, but showed also slight differences. DNA–DNA hybridizations with type strains of C. gwangjuense, C. formosense, and C. defluvii resulted in values below 70 %. Isolates 91A-561T and 91A-576 showed DNA–DNA hybridization values >80 % indicating that they belonged to the same species; but nucleic acid fingerprinting showed that the two isolates represent two different strains. DNA–DNA hybridization results and the differentiating biochemical and chemotaxonomic properties showed, that both strains 91A-561T and 91A-576 represent a novel species, for which the name Chryseobacterium geocarposphaerae sp. nov. (type strain 91A-561T=LMG 27811T=CCM 8488T) is proposed. Strains 91A-593T and JM-1085T represent two additional new species for which we propose the names Chyrseobacterium zeae sp. nov. (type strain JM-1085T=LMG 27809T, =CCM 8491T) and Chryseobacterium arachidis sp. nov. (type strain 91A-593T=LMG 27813T, =CCM 8489T), respectively. 相似文献
7.
《Systematic and applied microbiology》2021,44(6):126270
Exploration of unexplored habitats for novel actinobacteria with high bioactivity potential holds great promise in the search for novel entities. During the course of isolation of actinobacteria from desert soils, four actinobacteria, designated as 5K548T, 7K502T, 16K309T and 16K404T, were isolated from the Karakum Desert and their bioactivity potential as well as taxonomic provenances were revealed by comprehensive genome analyses. Pairwise sequence analyses of the 16S rRNA genes indicated that the four strains are representatives of putatively novel taxa within the prolific actinobacterial genus Saccharopolyspora. The strains have typical chemotaxonomic characteristics of the genus Saccharopolyspora by having meso-diaminopimelic acid as diagnostic diaminoacid, arabinose, galactose and ribose as whole-cell sugars. Consistent with this assignment, all of the isolates contained phosphatidylcholine in their polar lipid profiles and MK-9(H4) as the predominant menaquinone. The sizes of the genomes of the isolates ranged from 6.0 to 10.2 Mb and the associated G + C contents from 69.6 to 69.7 %. Polyphasic characterizations including determination of overall genome relatedness indices revealed that the strains are representatives of four novel species in the genus Saccharopolyspora. Consequently, isolates 5K548T, 7K502T, 16K404T and 16K309T are proposed as novel Saccharopolyspora species for which the names of Saccharopolyspora karakumensis sp. nov., Saccharopolyspora elongata sp. nov., Saccharopolyspora aridisoli sp. nov. and Saccharopolyspora terrae sp. nov. are proposed, respectively. Comprehensive genome analysis for biosynthetic gene clusters showed that the strains have high potential for novel secondary metabolites. Moreover, the strains harbour many antimicrobial resistance genes providing more evidence for their potentiality for bioactive metabolites. 相似文献
8.
Stewart A. Hill Stephen E. Scheckler James F. Basinger 《American journal of botany》1997,84(1):85-103
A new fern-like fossil plant is described from the lower Upper Devonian of southern Ellesmere Island, Canadian Arctic Archipelago. The plant occurs in an Archaeopteris-dominated flora preserved in the Nordstrand Point Formation (Mid-Late Frasnian) near Bird Fiord. The plant has a pinnate vegetative system with three branch orders and laminate sphenopteroid pinnules. Primary pinnae usually diverge from the main axis in distichous pairs (quadriseriate), but can depart singly (biseriate). Each primary pinna bears a basal catadromic aphlebia. Anatomically, the plant exhibits a mesarch, bipolar protostele that is ribbon- to clepsydropsoid-shaped in the main axis. Primary pinna traces are also initially bipolar and crescent-shaped, but may become four-ribbed before dividing into a pair of bipolar traces. The morphology and anatomy of this plant are nongymnospermous and are most similar to Zygopteridales (particularly Rhacophytaceae and Zygopteridaceae). The Frasnian age of Ellesmeris shows that laminated foliage had evolved in some zygopterid ferns much earlier than previously recognized. The Sphenopteris-like pinnules of Ellesmeris indicate the need for caution when attributing such a convergent foliar design to other plant groups, such as the Devonian gymnosperms. 相似文献
9.
Phenotypic and chemotaxonomic characteristics of five isolates of acetylenereducing (nitrogen-fixing) oligotrophic bacteria from a paddy soil were investigated. They showed similar phenotypic characteristics: they were aerobic, asporogenous, gram-negative, motile by a polar flagellum, and irregular rods. On full strength nutrient broth (NB) growth was severely suppressed, but well supported on 10-to 10000-fold diluted NB. They consumed glucose but produced no acid, and also utilized phenolic acids such as ferulic acid or p-coumaric acid. The cellular fatty acid composition, quinone system and DNA base composition of the isolates were investigated. Cellular fatty acids mainly consisted of straightchain unsaturated C18 : 1 (62–81% of total fatty acids). Ubiquinone Q-10 and a high guanine-plus-cytosine content (65.1–66.0 mol%) were found. The taxonomic status of the isolates is discussed and a new genus, Agromonas, with a single species Agromonas oligotrophica sp. nov., is proposed for these isolates. The type strain of A. oligotrophica is JCM 1494. 相似文献
10.
Zong-Jie Wang Zhi-Hong Xie Chao Wang Zong-Jun Du Guan-Jun Chen 《Antonie van Leeuwenhoek》2014,106(4):615-621
A novel Gram-stain-negative, rod-to-spiral-shaped, oxidase- and catalase- positive and facultatively aerobic bacterium, designated HS6T, was isolated from marine sediment of Yellow Sea, China. It can reduce nitrate to nitrite and grow well in marine broth 2216 (MB, Hope Biol-Technology Co., Ltd) with an optimal temperature for growth of 30–33 °C (range 12–45 °C) and in the presence of 2–3 % (w/v) NaCl (range 0.5–7 %, w/v). The pH range for growth was pH 6.2–9.0, with an optimum at 6.5–7.0. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the novel isolate was 93.3 % similar to the type strain of Neptunomonas antarctica, 93.2 % to Neptunomonas japonicum and 93.1 % to Marinobacterium rhizophilum, the closest cultivated relatives. The polar lipid profile of the novel strain consisted of phosphatidylethanolamine, phosphatidylglycerol and some other unknown lipids. Major cellular fatty acids were summed feature 3 (C16:1 ω7c/iso-C15:0 2-OH), C18:1 ω7c and C16:0 and the main respiratory quinone was Q-8. The DNA G+C content of strain HS6T was 61.2 mol %. Based on the phylogenetic, physiological and biochemical characteristics, strain HS6T represents a novel genus and species and the name Motiliproteus sediminis gen. nov., sp. nov., is proposed. The type strain is HS6T (=ATCC BAA-2613T=CICC 10858T). 相似文献
11.
Soo-Jin Kim Jae-Hyung Ahn Hang-Yeon Weon Moriyuki Hamada Ken-ichiro Suzuki Soon-Wo Kwon 《Journal of microbiology (Seoul, Korea)》2014,52(6):527-533
Two bacterial strains, KIS66-7T and 5GH26-15T, were isolated from soil samples collected in the South Korean cities of Tongyong and Gongju, respectively. Both strains were aerobic, Gram-stain-positive, mesophilic, flagellated, and rodshaped. A phylogenetic analysis revealed that both strains belonged to the family Microbacteriaceae of the phylum Actinobacteria. The 16S rRNA gene sequence of strain KIS66-7T had the highest similarities with those of Labedella gwakjiensis KSW2-17T (97.3%), Cryobacterium psychrophilum DSM 4854T (97.2%), Leifsonia lichenia 2SbT (97.2%), Leifsonia naganoensis JCM 10592T (97.0%), and Cryobacterium mesophilum MSL-15T (97.0%). Strain 5GH26-15T showed the highest sequence similarities with Leifsonia psychrotolerans LI1T (97.4%) and Schumannella luteola KHIAT (97.1%). The 16S rRNA gene sequence from KIS66-7T exhibited 96.4% similarity with that from 5GH26-15T. Strain KIS66-7T contained a B2γ type peptidoglycan structure with D-DAB as the diamino acid; MK-13, MK-12, and MK-14 as the respiratory quinones; ai-C15:0, ai-C17:0, and i-C16:0 as the major cellular fatty acids; and diphosphatidylglycerol, phatidylglycerol, and glycolipids as the predominant polar lipids. Strain 5GH26-15T had a B2β type peptidoglycan structure with D-DAB as the diamino acid; MK-14 and MK-13 as the respiratory quinones; ai-C15:0, i-C16:0, and ai-C{vn17:0} as the major cellular fatty acids; and diphosphatidylglycerol, phatidylglycerol, and glycolipids as the predominant polar lipids. Both strains had low DNA-DNA hybridization values (<40%) with closely related taxa. Based on our polyphasic taxonomic characterization, we propose that strains KIS66-7T and 5GH26-15T represent novel genera and species, for which we propose the names Diaminobutyricibacter tongyongensis gen. nov., sp. nov. (type strain KIS66-7T=KACC 15515T=NBRC 108724T) and Homoserinibacter gongjuensis gen. nov., sp. nov. (type strain 5GH26-15T=KACC 15524T=NBRC 108755T) within the family Microbacteriaceae. 相似文献
12.
13.
Carmen Falagán D. Barrie Johnson 《Extremophiles : life under extreme conditions》2014,18(6):1067-1073
An acidophilic gammaproteobacterium, isolated from a pit lake at an abandoned metal mine in south-west Spain, was shown to be distantly related to all characterized prokaryotes, and to be the first representative of a novel genus and species. Isolate MCF85 is a Gram-negative, non-motile, rod-shaped mesophilic bacterium with a temperature growth optimum of 32–35 °C (range 8–45 °C). It was categorized as a moderate acidophile, growing optimally at pH 3.5–4.0 and between pH 2.5 and 4.5. Under optimum conditions its culture doubling time was around 75 min. Only organic electron donors were used by MCF85, and the isolate was confirmed to be an obligate heterotroph. It grew on a limited range of sugars (hexoses and disaccharides, though not pentoses) and some other small molecular weight organic compounds, and growth was partially or completely inhibited by small concentrations of some aliphatic acids. The acidophile grew in the presence of >100 mM ferrous iron or aluminium, but was more sensitive to some other metals, such as copper. It was also much more tolerant of arsenic (V) than arsenic (III). Isolate MCF85 catalysed the reductive dissolution of the ferric iron mineral schwertmannite when incubated under micro-aerobic or anaerobic conditions, causing the culture media pH to increase. There was no evidence, however, that the acidophile could grow by ferric iron respiration under strictly anoxic conditions. Isolate MCF85 is the designated type strain of the novel species Acidibacter ferrireducens (=DSM 27237T = NCCB 100460T). 相似文献
14.
《Mycoscience》2019,60(5):307-312
Coprinopsis neocinerea sp. nov. (Basidiomycota, Agaricales, Psathyrellaceae), is a new Coprinoid ammonia fungus from broadleaf mixed forest in Vietnam. In macro- and micromorphology, this species is similar to C. cinerea, but differs in having upheaved and humpbacked abaxial side shape of basidiospores. Phylogenetic analysis with nuclear ribosomal internal transcribed spacer (ITS) data also supports this new taxon. 相似文献
15.
《Systematic and applied microbiology》2020,43(1):126050
Pirellula-like planctomycetes are ubiquitous aquatic bacteria, which are often detected in anoxic or micro-oxic habitats. By contrast, the taxonomically described representatives of these bacteria, with very few exceptions, are strict aerobes. Here, we report the isolation and characterization of the facultatively anaerobic planctomycete, strain PX69T, which was isolated from a boreal lake. Its 16S rRNA gene sequence is affiliated with the Pirellula-related Pir4 clade, which is dominated by environmental sequences retrieved from a variety of low-oxygen habitats. Strain PX69T was represented by ellipsoidal cells that multiplied by budding and grew on sugars, some polysaccharides and glycerol. Anaerobic growth occurred by means of fermentation. Strain PX69T grew at pH 5.5–7.5 and at temperatures between 10 and 30 °C. The major fatty acids were C18:1ω9c, C16:0 and C16:1ω7c; the major intact polar lipid was dimethylphosphatidylethanolamine. The complete genome of strain PX69T was 6.92 Mb in size; DNA G + C content was 61.7 mol%. Among characterized planctomycetes, the highest 16S rRNA gene similarity (90.4%) was observed with ‘Bythopirellula goksoyri’ Pr1d, a planctomycete from deep-sea sediments. We propose to classify PX69T as a novel genus and species, Lacipirellula parvula gen. nov., sp. nov.; the type strain is strain PX69T (=KCTC 72398T = CECT 9826T = VKM B-3335T). This genus is placed in a novel family, Lacipirellulaceae fam. nov., which belongs to the order Pirellulales ord. nov. Based on the results of comparative genome analysis, we also suggest establishment of the orders Gemmatales ord. nov. and Isosphaerales ord. nov. as well as an emendation of the order Planctomycetales. 相似文献
16.
《Systematic and applied microbiology》2021,44(6):126273
Ten Bifidobacterium strains, i.e., 6T3, 64T4, 79T10, 80T4, 81T8, 82T1, 82T10, 82T18, 82T24, and 82T25, were isolated from mantled guereza (Colobus guereza), Sumatran orangutan (Pongo abeli), silvery marmoset (Mico argentatus), golden lion tamarin (Leontopithecus rosalia), pied tamarin (Saguinus bicolor), and common pheasant (Phaisanus colchinus). Cells are Gram-positive, non-motile, non-sporulating, facultative anaerobic, and fructose 6-phosphate phosphoketolase-positive. Phylogenetic analyses based on the core genome sequences revealed that isolated strains exhibit close phylogenetic relatedness with Bifidobacterium genus members belonging to the Bifidobacterium bifidum, Bifidobacterium longum, Bifidobacterium pullorum, and Bifidobacterium tissieri phylogenetic groups. Phenotypic characterization and genotyping based on the genome sequences clearly show that these strains are distinct from each of the type strains of the so far recognized Bifidobacterium species. Thus, B. phasiani sp. nov. (6T3 = LMG 32224T = DSM 112544T), B. pongonis sp. nov. (64T4 = LMG 32281T = DSM 112547T), B. saguinibicoloris sp. nov. (79T10 = LMG 32232T = DSM 112543T), B. colobi sp. nov. (80T4 = LMG 32225T = DSM 112552T), B. simiiventris sp. nov. (81T8 = LMG 32226T = DSM 112549T), B. santillanense sp. nov. (82T1 = LMG 32284T = DSM 112550T), B. miconis sp. nov. (82T10 = LMG 32282T = DSM 112551T), B. amazonense sp. nov. (82T18 = LMG 32297T = DSM 112548T), pluvialisilvae sp. nov. (82T24 = LMG 32229T = DSM 112545T), and B. miconisargentati sp. nov. (82T25 = LMG 32283T = DSM 112546T) are proposed as novel Bifidobacterium species. 相似文献
17.
18.
De-Ming Wang James F. Basinger Pu Huang Le Liu Jin-Zhuang Xue Mei-Cen Meng Ying-Ying Zhang Zhen-Zhen Deng 《Proceedings. Biological sciences / The Royal Society》2015,282(1817)
The earliest known ovules in the Late Devonian (Famennian) are borne terminally on fertile branches and are typically enclosed in a cupule. Among these ovules are some that have terete integumentary lobes with little or no fusion. Here, we report a new taxon, Latisemenia longshania, from the Famennian of South China, which bears cupulate ovules that are terminal as well as opposite on the fertile axis. Each ovule has four broad integumentary lobes, which are extensively fused to each other and also to the nucellus. The cupule is uniovulate, and the five flattened cupule segments of each terminal ovule are elongate cuneate and shorter than the ovule. Associated but not attached pinnules are laminate and Sphenopteris-like, with an entire or lobate margin. Latisemenia is the earliest known plant with ovules borne on the side of the fertile axis and may foreshadow the diverse ovule arrangements found among younger seed plant lineages that emerge in the Carboniferous. Following the telome theory, Latisemenia demonstrates derived features in both ovules and cupules, and the shape and fusion of integumentary lobes suggest effective pollination and protection to the nucellus. Along with other recent discoveries from China, Latisemenia extends the palaeogeographic range of the earliest seed plants. 相似文献
19.
A new lycopod, Novgorodendron conophorum gen. et sp. nov., is described from the Upper Visean deposits of the Kamenka River, near the town of Borovichi (Novgorod Region). The morphology of the leaf cushions of the new plant implies its intermediate position between the families Sublepidodendraceae Chaloner et Boureau and Lepidodendraceae Endlicher. The bases of the leaf cushions have peculiar conical appendages, a previously unknown morphological feature not recorded from other lycopods. We propose the term basal conical appendages for them. The interpretation of some epidermal elements in the leaf cushions of the Lepidodendraceae is revised. The structures of the leaf cushions that were previously treated as either stomata or cells with cystoliths are shown to be sunken multicellular trichomes. 相似文献