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1.
The subfamily Mastophoroideae (Corallinaceae, Rhodophyta) is characterized by species possessing nongeniculate, uniporate tetrasporangial conceptacles without apical plugs, the presence of cell fusions, and the absence of secondary pit connections. However, molecular phylogenetic studies not including the type genus Mastophora indicated that the Mastophoroideae was polyphyletic. Our molecular phylogenetic analysis of the subfamily including the type genus using DNA sequences of SSU rDNA and plastid‐encoded gene of PSII reaction center protein D1 (psbA) revealed that Mastophora formed a robust clade only with Metamastophora. The other mastophoroid genera were divided into six lineages within the family Corallinaceae. Five supported lineages—(i) Pneophyllum; (ii) Hydrolithon gardineri (Foslie) Verheij et Prud’homme, Hydrolithon onkodes (Heydr.) Penrose et Woelk., and Hydrolithon pachydermum (Foslie) J. C. Bailey, J. E. Gabel et Freshwater; (iii) Hydrolithon reinboldii (Weber Bosse et Foslie) Foslie; (iv) Spongites; and (v) Neogoniolithon—were clearly distinguished by the combination of characters including the presence or absence of palisade cells and trichocytes in large, tightly packed horizontal fields and features of tetrasporangial and spermatangial conceptacles. Therefore, we amend the Mastophoroideae to be limited to Mastophora and Metamastophora with a thin thallus with basal filaments comprised of palisade cells, tetrasporangial conceptacles formed by filaments peripheral to fertile areas, and spermatangia derived only from the floor of male conceptacles. This emendation supports Setchell’s (1943) original definition of the Mastophoroideae as having thin thalli. We also propose the establishment of three new subfamilies, Hydrolithoideae subfam. nov. including Hydrolithon, Porolithoideae subfam. nov. including the resurrected genus Porolithon, and Neogoniolithoideae subfam. nov. including Neogoniolithon. Taxonomic revisions of Pneophyllum and Spongites were not made because we did not examine their type species.  相似文献   

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Phylogenetic analyses of rbcL gene sequences and of concatenated rbcL, psbA, and nuclear SSU rRNA gene sequences resolved the generitype of Lithothamnion, L. muelleri, in a clade with three other southern Australian species, L. kraftii sp. nov., L. saundersii sp. nov., and L. woelkerlingii sp. nov. Cold water boreal species currently classified in Lithothamnion and whose type specimens have been sequenced are transferred to Boreolithothamnion gen. nov., with B. glaciale comb. nov. as the generitype. The other species are B. giganteum comb. nov., B. phymatodeum comb. nov., and B. sonderi comb. nov., whose type specimens are newly sequenced, and B. lemoineae comb. nov., B. soriferum comb. nov., and B. tophiforme comb. nov., whose type specimens were already sequenced. Based on rbcL sequences from the type specimens of Lithothamnion crispatum, L. indicum, and L. superpositum, each is recognized as a distinct species and transferred to the recently described Roseolithon as R. crispatum comb. nov., R. indicum comb. nov., and R. superpositum com. nov., respectively. To correctly assign species to these three genera based only on morpho-anatomy, specimens must have multiporate conceptacles and some epithallial cells with flared walls. The discussion provides examples demonstrating that only with phylogenetic analyses of DNA sequences can the evolution of morpho-anatomical characters of non-geniculate corallines be understood and applied at the correct taxonomic rank. Finally, phylogenetic analyses of DNA sequences support recognition of the Hapalidiales as a distinct order characterized by having multiporate tetra/bisporangial conceptacles, and not as a suborder of Corallinales whose tetra/bisporangial conceptacles are uniporate.  相似文献   

4.
Mesophyllum sphaericum sp. nov. is described based on spherical maërl individuals (up to 10 cm) collected in a shallow subtidal maërl bed in Galicia (NW Spain). The thalli of these specimens are radially organized, composed of arching tiers of compact medullary filaments. Epithallial cells have flattened to rounded outermost walls, and they occur in a single layer. Subepithallial initials are as long as, or longer than the daughter cells that subtend them. Cell fusions are abundant. Multiporate asexual conceptacles are protruding, mound‐like with a flattened pore plate, lacking a peripheral raised rim. Filaments lining the pore canal and the conceptacle roof are composed of five to six cells with straight elongate and narrow cells at their base. Carposporangial conceptacles are uniporate, protruding, and conical. Spermatangial conceptacles were not observed. Molecular results placed M. sphaericum near to M. erubescens, but M. sphaericum is anatomically close to M. canariense. The examination of the holotype and herbarium specimens of M. canariense indicated that both species have pore canal filaments with elongate basal cells, but they differ in number of cells (five to six in M. sphaericum vs. four in M. canariense). Based on the character of pore canal filaments, M. canariense shows similarities with M. erubescens (three to five celled). The outermost walls of epithallial cells of M. canariense are flared compared to the round to flattened ones of M. erubescens, the latter being widely accepted for the genus Mesophyllum. The addition of M. sphaericum as new maërl‐forming species suggests that European maërl beds are more biodiverse than previously understood.  相似文献   

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Holococcolithophorids, pyrmnesiophytes having only one type of calcareous element in their coccoliths, are delicate and not commonly recorded in recent and fossil marine floras. There are few records of these organisms from the Indian Ocean and 26 species from there are included in this report. Although the group, generally assigned to a single family, the Calyptrosphaeraceae, may contain species that are part of the life history of heterococcolith-bearing cells in other stages, so little is known of this aspect of their biology that one must continue, at the present time, to treat them as independent taxonomic entities. A key is provided for the known holococcolithophorid genera. A new genus, Gliscolithus, and three new species, Gliscolithus amitakarenae, Calyptrosphaera heimdalae, and Helladosphaera pienaarii are described. The following new combinations are proposed: Calyptrolithina fragaria (Kamptner) comb. nov., Calyptrolithina gaarderae (Borsetti et Cati) comb. nov., Calyptrolithina isselii (Borsetti et Cati) comb. nov., Calyptrolithina lafourcadii (Lecal) comb. nov., Calyptrolithina magnaghii (Borsetti et Cati) comb. nov., Calyptrolithina multipora (Gaarder) comb. nov., Calyptrolithina porritectum (Heimdal) comb. nov., Calyptrolithina wettsteinii (Kamptner) comb. nov., Calyptrolithophora catillifera (Kamptner) comb. nov., Calyptrolithophora galea (Lecal-Schlauder) comb. nov., Dactylethra pirus (Kamptner) comb. nov., Helladosphaera arethusae (Kamptner) comb. nov., Helladosphaera gracilis (Kamptner) comb. nov., Homozygosphaera strigilis (Gaarder) comb. nov. and Syracolithus schilleri (Kamptner) comb. nov. The new combination in the genus Dactylethra Gartner for the first time brings an extant species into this genus that formerly contained only fossil species. It is pointed out that the enlarged zygoliths in stomatal areas of Corisphaera and the helladoliths in stomatal regions of Helladosphaera have intergrading types and are not distinctive enough characteristics to separate these genera.  相似文献   

7.
Type material of Lithothamnion flavescens Kjellman, originally described from Karlsøy (Troms) and Karmakul Bay (Novaya Zemlya), is re-examined and a lectotype is selected. Type specimens and other collections from NW Spitsbergen and North Norway possess distinctive characters of the genus Leptophytum, including the development of flattened epithallial cells, short subepithallial cells, and simple spermatangial structures. Leptophytum flavescens (Kjellman) comb. nov. resembles the generitype Leptophytum laeve, differing in having: (1) a thicker perithallium, to 900?µm (vs. 350?µm in L. laeve), that embeds older conceptacles, and (2) non-differentiated (in size or shape) pore cells of multiporate roofs. An epitype for L. laeve is also selected, which consolidates the status of this species and the genus, in agreement with the current literature and all publications prior to 1996.  相似文献   

8.
梭菌属分类研究进展:现状和展望   总被引:2,自引:0,他引:2  
目前构成梭菌属的微生物在系统发育和表型特征上不一致。多相分类数据表明,梭菌属物种之间差异大。大量基于16S rRNA 基因的系统发育研究表明,梭菌属应被限定为梭菌属类群I,作为狭义梭菌属(Clostridium sensu stricto)。尽管有这方面认识,梭菌属新物种仍持续增加,这些新物种并不能与梭菌属类群I 和标准种丁酸梭菌(C. butryicum)形成一致分支,引发梭菌属分类上的混乱。本文明确了梭菌属物种的范围,即只包括模式种和梭菌属类群I。此外,4 个物种念珠状真杆菌(Eubacterium moniliforme)、旋舞真杆菌(Eubacterium tarantellae)、最大八叠球菌(Sarcina maxima)和胃八叠球菌(Sarcina ventriculi)应被调至梭菌属,分别命名为念珠状梭菌(Clostridium moniliforme)、旋舞梭菌(Clostridium tarantellae)、最大梭菌(Clostridium maximum)和胃梭菌(Clostridium ventriculi)。一个新属哈撒韦氏菌属(Hathewaya)被提议成立,3 个梭菌属物种溶组织梭菌(Clostridium histolyticum)、泥渣梭菌(Clostridium limosum)和解朊梭菌(Clostridiumproteolyticum)重新归为溶组织哈撒韦氏菌(Hathewaya histolytica)、泥渣哈撒韦氏菌(Hathewaya limosa)和解朊哈撒韦氏菌(Hathewaya proteolytica),其中Hathewaya histolytica 为模式种。  相似文献   

9.
《Journal of bryology》2013,35(4):268-276
Abstract

Two little known species of Cheilolejeunea, C. microscypha (Hook.f. & Taylor) M.Wigginton, comb. nov. (a reinstated St Helena liverwort), and C. rotalis (Hook.f. & Taylor) M.Wigginton comb. nov., endemic to St Helena, South Atlantic Ocean, are described and illustrated, and oil bodies of C. ascensionis (Hook.f. & Taylor) Grolle are newly described and illustrated.  相似文献   

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Of the genera within the coralline algal subfamily Melobesioideae, the genera Leptophytum Adey and Phymatolithon Foslie have probably been the most contentious in recent years. In recent publications, the name Leptophytum was used in quotation marks because South African taxa ascribed to this genus had not been formally transferred to another genus or reduced to synonymy. The status and generic disposition of those species (L. acervatum, L. ferox, L. foveatum) have remained unresolved ever since Düwel and Wegeberg (1996) determined from a study of relevant types and other specimens that Leptophytum Adey was a heterotypic synonym of Phymatolithon Foslie. Based on our study of numerous recently collected specimens and of published data on the relevant types, we have concluded that each of the above species previously ascribed to Leptophytum represents a distinct species of Phymatolithon, and that four species (incl. P. repandum) of Phymatolithon are currently known to occur in South Africa.Here we present detailed illustrated accounts of each of the four species, including: new data on male and female/carposporangial conceptacles; ecological and morphological/anatomical comparisons; and a review of the information on the various features used previously to separate Leptophytum and Phymatolithon. Southern African species ascribed to the genus Phymatolithon may be separated from one another in the field by their growth forms, the substrata on which they are generally found, and the colour of living thalli. A key for identifying southern African specimens in the field is included. Our data support the conclusion that the characters upon which Leptophytum is based are unreliable for generic delimitation from Phymatolithon.  相似文献   

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WithinFusarium sambucinum Fuckel sensu lato three species were differentiated:F. sambucinum Fuckel s. str.,F. torulosum (Berk. et Curt.) Nirenberg comb. nov. andF. venenatum Nirenberg sp. nov. They are described and illustrated in detail.  相似文献   

14.
Sequence data generated during a Canadian barcode survey (COI-5P) of the tribes Polysiphonieae and Streblocladieae, a large and taxonomically challenging group of red algae, revealed significant taxonomic confusion and hidden species diversity. Polysiphonia pacifica Hollenberg, P. paniculata Montagne, P. stricta (Dillwyn) Greville and Vertebrata fucoides (Hudson) Kuntze were all complexes of two or more genetically distinct yet overlooked species. One variety of P. pacifica was elevated to the rank of species as P. determinata (Hollenberg) Savoie & Saunders, stat. nov. Several new additions to the Canadian flora were recorded including P. kapraunii Stuercke & Freshwater and P. morrowii Harvey. Subsequent multi-gene (COI-5P, LSU and rbcL) phylogenetic analyses confirmed that the genus Polysiphonia Greville was polyphyletic, and currently assigned species resolved with many other genera. Polysiphonia sensu stricto was restricted to a group of species that formed a monophyletic lineage with the type, Polysiphonia stricta. Carradoriella P.C.Silva was resurrected based on the South African species Carradoriella virgata (C.Agardh) P.C.Silva. Species previously attributed to Polysiphonia were transferred to Carradoriella, Leptosiphonia and Vertebrata as well as to three new genera described here: Acanthosiphonia gen. nov., based on A. echinata (Harvey) comb. nov.; Eutrichosiphonia gen. nov. for E. confusa (Hollenberg) comb. nov. and E. sabulosia (B.Kim & M.S.Kim) comb. nov.; and Kapraunia gen. nov., which includes K. schneideri (Stuercke & Freshwater) comb. nov. and three additional species.  相似文献   

15.
Synarthrophyton gen. nov. is described based on southern Australian material of Melobesia patena Hooker fils & Harvey, which shows features intermediate between Mesophyllum Lemoine and Lithothamnium Philippi. It has the thin-walled rounded epithallial cells and coaxial hypothallium characteristic of Mesophyllum and the type of procarp and male structures common to Lithothamnium. Synarthrophyton is unique within the subfamily Melobesioideae (J. E. Areschoug) Yendo because it displays secondary pit connections. Details of the vegetative and reproductive morphology of S. patena (Hooker fils. & Harvey) comb. nov. are given and its taxonomic position in the Corallinaceae Lamouroux discussed.  相似文献   

16.
Type material of Navicula kotschyi was studied, and this species was transferred to Dorofeyukea gen. nov. as D. kotschyi comb. nov. Dorofeyukea was described on the basis of DNA sequence and morphological data. Additional species assigned to this genus that were previously included in Navicula include: D. ancisa comb. nov., D. grimmei comb. nov., D. ivatoensis comb. nov., D. orangiana comb. nov., D. rostellata comb. nov. & stat. nov., D. savannahiana comb. nov., D. tenuipunctata comb. nov., and D. texana comb. nov. All Dorofeyukea species share the same morphological features, including having a narrow stauroid fascia surrounded by 1–3 irregularly shortened striae, uniseriate, and weakly radiate striae, circular, or rectangular puncta in the striae that are covered internally by dome‐shaped hymenes, presence of a pseudoseptum at each apex and absence of septa. Partial DNA sequences of SSU and rbcL loci show Dorofeuykae belongs to the clade of stauroneioid diatoms together with Stauroneis, Prestauroneis, Craticula, Karayevia, Madinithidium, Fistulifera, Parlibellus, and, possibly, Schizostauron. A new species from the monoraphid genus Madinithidium, M. vietnamica sp. nov., was described based on valve and chloroplast morphology as well as DNA sequence data.  相似文献   

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A multigene phylogeny using COI‐5P (mitochondrial cytochrome c oxidase subunit 1), psbA (PSII reaction center protein D1), and EF2 (elongation factor 2) sequence data for members of the tribe Corallineae was constructed to assess generic boundaries. We determined that traditional reliance on conceptacle position as an indicator of generic affinities in the Corallineae is not supported and taxonomic changes are required. We found that species currently assigned to Pseudolithophyllum muricatum resolved within the Corallineae in all analyses. This is the first record of crustose members in the subfamily Corallinoideae. Further‐more, the genus Serraticardia was polyphyletic; we propose to synonomize Serraticardia with Corallina, transfer the type species Smaxima to Corallina (Cmaxima (Yendo) comb. nov.), and describe the new genus Johansenia for Smacmillanii (Jmacmillanii (Yendo) comb. nov.). Our molecular data also indicate that species in the genus Marginisporum have evolutionary affinities among species of Corallina and these genera should also be synonymized. This necessitates the combinations Caberrans (Yendo) comb. nov. for Maberrans (Yendo) Johansen & Chihara, Ccrassissima (Yendo) comb. nov. for M. crassissimum (Yendo) Ganesan, and C. declinata (Yendo) comb. nov. for M. declinata (Yendo) Ganesan. Corallina elongata was divergent from all other members of Corallina and is transferred to a new genus, Ellisolandia (E. elongata (J. Ellis & Solander) comb. nov). In addition, COI‐5P and internal transcribed spacer (ITS) data combined with morphological characters were used to establish that rather than the four Corallina species recognized in Canada, there are nine.  相似文献   

19.
The genus Terpnosia Distant is newly defined. Terpnosia elegans (Kirby) stat. rev. is resurrected from junior synonymy with Terpnosia psecas (Walker). Seven species are now considered to belong to Terpnosia sensu stricto, including two species currently placed in this genus: T. psecas (Walker) and T. elegans (Kirby) stat. rev. Five species are transferred from Pomponia Stål to Terpnosia: T. polei (Henry) comb. nov., T. lactea (Distant) comb. nov., T. similis (Schmidt) comb. nov., T. simusa (Boulard) comb. nov., and T. graecina (Distant) comb. nov. Yezoterpnosia Matsumura stat. rev. is resurrected from junior synonymy with Terpnosia. Six species formerly in the genus Terpnosia are transferred to Yezoterpnosia: Y. nigricosta (De Motschulsky), Y. ichangensis (Liu) comb. nov., Y. shaanxiensis (Sanborn) comb. nov., Y. vacua (Olivier) comb. nov., Y. obscura (Kato) comb. nov., and Y. fuscoapicalis (Kato) comb. nov. Terpnosia is placed in the subtribe Psithyristriina of the tribe Cicadini, and Yezoterpnosia is placed in the subtribe Leptopsaltriina of Cicadini. Terpnosiina syn. nov. is synonymized with Psithyristriina.  相似文献   

20.
Molecular phylogenetic analyses of 18S rDNA (SSU) gene sequences confirm the placement of Crusticorallina gen. nov. in Corallinoideae, the first nongeniculate genus in an otherwise geniculate subfamily. Crusticorallina is distinguished from all other coralline genera by the following suite of morpho‐anatomical characters: (i) sunken, uniporate gametangial and bi/tetrasporangial conceptacles, (ii) cells linked by cell fusions, not secondary pit connections, (iii) an epithallus of 1 or 2 cell layers, (iv) a hypothallus that occupies 50% or more of the total thallus thickness, (v) elongate meristematic cells, and (vi) trichocytes absent. Four species are recognized based on rbcL, psbA and COI‐5P sequences, C. painei sp. nov., the generitype, C. adhaerens sp. nov., C. nootkana sp. nov. and C. muricata comb. nov., previously known as Pseudolithophyllum muricatum. Type material of Lithophyllum muricatum, basionym of C. muricata, in TRH comprises at least two taxa, and therefore we accept the previously designated lectotype specimen in UC that we sequenced to confirm its identity. Crusticorallina species are very difficult to distinguish using morpho‐anatomical and/or habitat characters, although at specific sites, some species may be distinguished by a combination of morpho‐anatomy, habitat and biogeography. The Northeast Pacific now boasts six coralline endemic genera, far more than any other region of the world.  相似文献   

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