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1.
A new species, Halichrysis corallinarius sp. nov. is described from coral reef habitats in southwest Puerto Rico as well as from Grand Cayman Island. The new species produces strap‐shaped thalli supported above the substrata by abundant peg‐like stipes. The lobed branches are frequently anastomosed with colonies measuring to 4.0 cm broad with individual axes measuring to 7.0 mm across. Algae possess up to five layers of medullary cells with frequent open spaces in the medulla. Tetrasporangia, measure to 19 × 25 μm, and are borne in sori limited to ventral surfaces. Gametophytes are monoecious and hemispherical carposporophytes are produced dorsally, measuring to 900 μm in diameter and 600 μm high.  相似文献   

2.
A new Metapeyssonnelia species that comprises up to 7% bottom cover at shallow‐water reef habitats in southwest Puerto Rico is described herein. It forms conspicuous orange encrustations on hard substrata and does not grow on living coral as does its two Caribbean congeners. The new species possesses conspicuous, to 30 cm in extent, tightly adherent crusts up to 950 μm thick, only hypobasal calcification, hypothallial cells arranged in broad flabellules and superficial (raised) tetrasporangial and carposporangial nemathecia. Tetrasporangia are pedicellate, borne laterally from cup‐like cells that are derived from basal paraphysal cells. Tetrasporangia measure up to 120 μm long and individual carposporangia to 80 μm long. The new species differs from other Metapeyssonnelia species developmentally in that perithallial cells at mid thallus height will divide laterally to form a new hypothallium. Small subunit gene sequences relate the new species to the two Metapeyssonnelia species that are previously known from Puerto Rico.  相似文献   

3.
A new genus and species of red alga in the Rhodymeniaceae, Grammephora peyssonnelioides, is described from both shallow and deepwater habitats in the Solomon Islands, South Pacific. The new genus and species is characterized by prostrate overlapping lobes with a strongly cartilaginous flexible texture, distinct surface linear markings perpendicular to the growing margins, and a compact three to four celled medulla of relatively small refractive cells. Tetrasporangia are elongate and decussately divided, and occur in large scattered dorsal surface sori. Cystocarps are prominent and conical, on the dorsal surface of the blade, with a network of nutritive filaments and basal nutritive tissue around the suspended, centrally located carposporophyte, with all gonimoblast initials becoming carposporangia. The columnar fusion cell is uniquely crowned by a ring of discoid cells of nonalgal origin.  相似文献   

4.
A new species of the Raphidophyceae, Haramonas pauciplastida sp. nov. from Canada is described. The genus Haramonas has been described based on the type species Haramonas dimorpha and currently only two species are known. This new alga belongs to the genus because it possesses a tubular invagination at the posterior end of the cell, producing a large amount of mucilage and generating both motile and non-motile phases in its life cycle. The chloroplast color of H. pauciplastida is yellowish green, and is similar to that of Haramonas viridis Horiguchi et Hoppenrath . However, this alga differs from the other species of the genus in that it possesses fewer chloroplasts, which are rarely overlapping. The ultrastructual study shows differences between these two species in the number of thylakoids in the lamella, the presence of a scattered pyrenoid matrix, and the position of the plastoglobuli. The phylogenetic analyses of the small subunit ribosomal RNA gene from the Haramonas species reveal that three species can be distinguished genetically from each other and they form a robust clade in the Raphidophyceae. This result supports the notion that the characteristic features of Haramonas are synapomorphies. This is the first report of molecular data from the Haramonas species.  相似文献   

5.
A new species, Erythroglossum latum, is described based on specimens from Fukushima Prefecture along the east coast of Honshu, Japan. This species differs from Erythroglossum pinnatum Okamura in having a broader main blade, a clear midrib and lateral branches that are smaller in size and not clearly constricted at the base.  相似文献   

6.
Two species of Phycodrys, Phycodrys quercifolia (Bory) Skottsberg and Phycodrys profunda E.Y.Dawson were previously recorded from New Zealand. However, an examination of Phycodrys collections from the New Zealand region showed that all were morphologically different from P. quercifolia (Type locality: the Falkland Islands) and P. profunda (Type locality: CA, USA). RbcL sequence analyses established that the New Zealand Phycodrys species formed a natural assemblage within the genus, consisting of three new species: P. novae-zelandiae sp. nov., P. franiae sp. nov. and P. adamsiae sp. nov. Phycodrys novae-zelandiae is the largest of the three, up to 20 cm in height, with a distinct midrib and multicellular, opposite to subopposite lateral macroscopic veins. It has entirely monostromatic blades except near the midrib and veins, and its procarp contains a three-celled sterile group one (st1) and a one-celled sterile group two (st2). Phycodrys franiae was previously treated as a cryptic species among herbarium collections of P. ‘quercifolia’. It is smaller (4–11 cm high) with weakly developed midribs and veins, the blade is tristromatic throughout, except at the growing margins, and the procarp consists of a four-celled st1 and a two–three-celled st2. Phycodrys adamsiae, previously reported as P. profunda, is a small decumbent or prostrate plant, 1–8 cm long, with a midrib and inconspicuous lateral veins. The blades are tristromatic with serrated margins, two–four-celled surface spines and multicellular marginal holdfasts that differ from those of Californian specimens. The tetrasporangia are borne on marginal bladelets. Phylogenetic analyses place the New Zealand species in a separate group that is distantly removed from most other Phycodrys species.  相似文献   

7.
Phylogenetic analysis of nucleotide data from small subunit ribosomal DNA (SSU rDNA) sequences (ca. 1685 bp.) was performed on 19 taxa of the Onygenales and three related mitosporic fungi. Phylogenetic trees were constructed by the neighbor-joining method with the sequence data of related taxa obtained from DNA databases. The species in the Onygenales form two clusters and seven subclusters, and the tree topology reflects the traditional classification by Currah (1985) with some exceptions. The Myxotrichaceae is placed in the different lineage, separate from other plectomycetous taxa and among the Leotiales and the Erysiphales. Furthermore, two separate lineages in the Myxotrichaceae were found. Tree topology suggested the Onygenaceae is polyphyletic and composed of three subgroups; 1) most members of Onygenaceae, 2)Spiromastix warcupii, and 3) pathogenic dimorphic fungi classified inAjellomyces.  相似文献   

8.
A new red alga from Jeju Island, Korea is described. The alga is assigned to Acanthopeltis, Gelidiaceae by the characteristics of terete erect axes, sympodial growth, and suborbicular branchlets that are amplexi‐caul at the base. Acanthopeltis longiramulosaY. Lee et Kim is characterized by a discoid holdfast with a few stolons, rhizoids arising from the apex of the branchlet, an erect terete axis diverging into a few branches, longish obpyriform to lanceolate branchlets with smooth surfaces, and tetrasporangial stichidia or sper‐matangial and cystocarps appendages on the marginal region of the branchlet. A. longiramulosa is more closely related to Acanthopeltis japonica than Acanthopeltis hirsuta in terms of thallus morphology. However, A. longiramulosa is easily distinguished from A. japonica, which has suborbicular branchlets with setaceous processes on both surfaces.  相似文献   

9.
Vegetative and reproductive development of Neosiphonia flavimarina gen. et sp. nov. (Rhodomelaceae, Ceramiales) from Bangpo on the western coast of Korea was investigated. This species is superficially similar to Polysiphonia, but differs distinctly from the latter in vegetative and reproductive structures. The plants attach by a solid disk composed of a dense cluster of rhizoids cut off from the pericentral cell wall, and bear erect indeterminate branches producing the lateral-branch initials from successive segments in a spiral arrangement. The procarps have a three-celled carpo-gonial branch. Spermatangial branches are formed on a primary branch of the trichoblasts, terminating in a single or occasionally two large, sterile cells. Tetra-sporangia are produced from the second pericentral cell adjacent to the trichoblast basal cell on indeterminate branches, and arranged spirally. Comparing several taxonomic characters among related genera, Neosiphonia occupies an independent phylogenetic position from Polysiphonia and leads to the conclusion that the genus may have a strong link with Fernandosiphonia which has a unilateral branching system. Relevant nomenclatural changes for several Polysiphonia species are also proposed.  相似文献   

10.
A new member of Delesseriaceae (Ceramiales, Rhodophyta) is described from Southern Taiwan and the Philippines. On the basis of comparative vegetative and reproductive morphology, and phylogenetic analysis inferred from nuclear-encoded large-subunit ribosomal DNA sequences (LSU rDNA), we conclude that it belongs in the genus Drachiella, tribe Schizoserideae, subfamily Phycodryoideae. The new taxon shares with other Drachiella species the absence of macro- and microscopic veins; diffuse growth by marginal and intercalary meristematic cells; a polystromatic, lobed thallus; abundance of rhizoidal marginal proliferations used for attachment; convoluted plastids in surface cells; abundant secondary pit connections among adjacent vegetative cells; large intercellular spaces between surface cells; procarps confined to the upper side of the thallus, circular in outline, consisting of a supporting cell bearing a strongly curved carpogonial branch and two sterile groups that remain undivided; vertical division of gonimoblast initial from auxiliary cell, and unilateral, monopodial branching of gonimoblasts; and mature cystocarps with a massive candelabrum-like fusion cell of fused gonimoblasts bearing carposporangia in branched chains. It is distinguished from the other members of the genus by thalli that consist of extensive tangled mats of prostrate and overlapping decumbent blades, procarps confined to the upper side of the thallus, and the lack of basal stalks or stipes. Whereas the Schizoserideae is predominantly a Southern Ocean tribe, one of the tribe's four genera, Drachiella, was known only from the eastern Atlantic and Mediterranean. We herein report the first record of the genus for the Indo-Pacific Ocean, and describe Drachiella liaoii, sp. nov., as a fourth species in the genus.  相似文献   

11.
Polysiphonia sensu lato comprises approximately 200 species, which are currently assigned to several different genera. To date, one of these genera, namely, Polysiphonia, has been reported to have 17 species. Here, we describe for the first time P. freshwateri sp. nov. and P. koreana sp. nov. from Uljin and Ulleung Island, Korea, based on morphological and molecular evidence. Polysiphonia freshwateri sp. nov. and P. koreana sp. nov. are characterized by having the typical Polysiphonia features. Polysiphonia freshwateri sp. nov. is further characterized by having abundant trichoblasts, conspicuous scar cells, and tetrasporangia arranged in spiral series. Polysiphonia koreana sp. nov. is further characterized by having very scarce scar cells placed between two pericentral cells, from which cicatrigenous branches arise. The results of our rbcL sequence analyses support the taxonomic placement of P. freshwateri sp. nov. and P. koreana sp. nov. within Polysiphonia.  相似文献   

12.
Two actinomycete strains isolated from sputum between 1999 and 2001 in Japan were provisionally assigned to the genus Nocardia based on morphological criteria. These isolates were further studied in order to determine their specific taxonomic status. Detailed chemotaxonomic characterization and 16S rDNA gene sequence analysis of these isolates also confirmed that they belong to the genus Nocardia. The 16S rDNA sequence data of the two strains showed that they are most similar to that of Nocardia carnea and Nocardia flavorosea. However, DNA-DNA relatedness data showed that the two strains could be distinguished from N. carnea and N. flavorosea and therefore represented two new species within the genus Nocardia. The designation of the two isolated strains are Nocardia testaceus for IFM 0937(T) (=JCM 12235(T), DSM 44765(T)) and Nocardia senatus for IFM 10088(T) (=JCM 12236(T), DSM 44766(T)).  相似文献   

13.
Cryptonemia specimens collected in Bermuda over the past two decades were analysed using gene sequences encoding the large subunit of the nuclear ribosomal DNA and the large subunit of RuBisCO as genetic markers to elucidate their phylogenetic positions. They were additionally subjected to morphological assessment and compared with historical collections from the islands. Six species are presently found in the flora including C. bermudensis comb. nov., based on Halymenia bermudensis, and the following five new species: C. abyssalis, C. antricola, C. atrocostalis, C. lacunicola and C. perparva. Of the eight species known in the western Atlantic flora prior to this study, none is found in Bermuda. Specimens reported in the islands in the 1900s attributed to C. crenulata and C. luxurians are representative of the new species, C. antricola and C. atrocostalis, respectively.  相似文献   

14.
Two new taxa of Liagoraceae (Nemaliales) are described from Western Australia. Gloiotrichus fractalis gen. et sp. nov. has been collected from 3–20 m depths at the Houtman Abrolhos, Western Australia. Plants are calcified, extremely lubricous, and grow to 17 cm in length. Carpogonial branches are straight, 6 or 7 cells in length, arise from the basal or lower cells of cortical fascicles, and are occasionally compound. Branched sterile filaments of narrow elongate cells arise on the lower cells of the carpogonial branch prior to gonimoblast initiation, at first on the basal cells, then on progressively more distal cells. Following presumed fertilisation the carpogonium divides transversely, with both cells giving rise to gonimoblast filaments. The distal cells of the carpogonial branch then begin to fuse, with fusion progressing proximally until most of the cells of the carpogonial branch are included. As fusion extends, the filaments on the carpogonial branch are reduced to the basal 2 or 3 cells. The gonimoblast is compact and bears terminal carposporangia. Spermatangial clusters arise on subterminal cells of the cortex, eventually displacing the terminal cells. The sequence of pre- and post-fertilisation events occurring in the new genus separates it from all others included in the Liagoraceae, although it appears to have close affinities with the uncalcified genus Nemalion. Ganonema helminthaxis sp. nov. was collected from 12 m depths at Rottnest Island, Western Australia. Plants are uncalcified and mucilaginous, the axes consisting of a few (< 10) primary medullary filaments, each cell of which gives rise to a cortical fascicle at alternate forks of the pseudodichotomies borne on successive medullary cells. Subsidiary (adventitious) filaments and rhizoids comprise the bulk of the thallus. Carpogonial branches are straight, (3-)4(-6) cells in length, arise on the basal 1–4 cells of the cortical fascicles, and are frequently compound. Carposporophytes develop from the upper of two daughter cells formed by a transverse division of the fertilised carpogonium. Ascending and descending sterile filaments girdle the carpogonial branch cells and arise mostly on the supporting cell prior to fertilisation. Ganonema helminthaxis is the first completely non-calcified member of the genus, and its reproductive and vegetative morphology supports the recognition of Ganonema as a genus independent from Liagora. Liagora codii Womersley is a southern Australian species displaying features of Ganonema, to which it is transferred.  相似文献   

15.
16.
A new species Phycodrys valentinae Seliv. et Zhigad. from the northwest of the Bering Sea, distinct from other species of the genus Phycodrys by the presence of a distromatic lamina and by the arrangement of basal generative prolifications, was described. Based on the analysis of the morphological and anatomic traits of species of the genus Phycodrys, P. serratiloba (Rupr.) A. Zin., which was considered as synonym of P. riggii Gardn. to the present [27, 28, 30], was reinstated as an independent species. The taxonomic status of other representatives of the genus Phycodrys of the studied region is considered. In our opinion, five species of the genus Phycodrys (P. serratiloba, P. riggii, P. amchitkensis, P. vinogradovae, and P. valentinae) grow in the seas of the Russian Far East.  相似文献   

17.
Two new species of Martensia (Delesseriaceae, Rhodophyta) are described from Jeju Island, Korea. Martensia jejuensis is characterized by the thallus of long linear axes and a proximal membranous part (initial blade), the linear axes that are derived from the longitudinal lamellae of the latticework, the flabellate bladelets arising from the linear axes terminally and laterally, the leading margins of the latticework giving rise to spine‐like or spatulate projections at intervals, and tetrasporangia borne on the whole thallus except for the spatulate projections. Martensia bibarii is characterized by the fimbriate aspect, the ribbon‐like blade with lobes, the flabellate bladelets derived from the lobes of the blade, the bladelets bearing the fringe or the latticework distally, the fringe consisting of many fine and strap‐shaped lamellae, and tetrasporangia borne only on the blade.  相似文献   

18.
A new unicellular red alga, Corynoplastis japonica gen. et sp. nov., is described from Tobishima, Japan. Cells are spherical, 18–33 µm in diameter, pale purple to brownish red and surrounded by a mucilaginous sheath. A single chloroplast with many lobes extends from the cell periphery to the cell center. A peripheral thylakoid is present. A pyrenoid occurs at each innermost chloroplast lobe end and one or two thylakoids are present in the pyrenoid matrix. The nucleus is eccentric to peripheral and Golgi bodies are scattered throughout the cell and associated with endoplasmic reticulum. Cells have a slow random gliding motility. The low molecular weight carbohydrate mannitol is present in the cells. Molecular phylogenetic analysis indicates that this alga is closely related to members of the genus Rhodella. A new order, Dixoniellales, is established for Dixoniella, Neorhodella and Glaucosphaera based on molecular and ultrastructural evidence (Golgi bodies associated only with the nucleus). The redefined order Rhodellales in which Rhodella and Corynoplastis are placed is characterized ultrastructurally by Golgi bodies scattered throughout the cytoplasm and associated with endoplasmic reticulum.  相似文献   

19.
Thecadinium inclinatum Balech and four new marine sand‐dwelling species of the dinoflagellate genus Thecadinium are described from the sandy beaches along the coast of Shikoku, Japan. Thecadinium inclinatum is thecate, bilaterally flattened, elliptical in shape, non‐photosynthetic, and measures 55–75 μ in length and 43–59 μ in depth. The epi‐ and hypotheca theca are semielliptical and the thecal surface is smooth with small pores. The plate formula is Po (pore plate), 3′, 7″,?c,?s, 5″′1″′.Thecadinium ovatum sp. nov. is thecate, non‐photosynthetic, bilaterally flattened and almost oval in lateral view. The cell measures 40–50 μm in length and 33–40 μm in depth. The hypotheca has two or three strong antapical spines. The plate formula is 3′, 6″,6c, 5s?, 5″′, 1″′. Thecadinium striatum sp. nov. is thecate, non‐photosynthetic, bilaterally flattened and somewhat elliptical in lateral view. The cell is 33–41 μm long and 23–30 μm deep. Several striae are present on the hypotheca. The plate formula is 3′, 6″, 6c, 5s?, 5″′, 1″″. Thecadinium yashimaense sp. nov. is bilaterally flattened, photosynthetic and elliptical in ventral view. The cell is 44–65 μm long and 23–36 μm wide. The thecal surface is smooth with small pores. he cingulum forms a steep left–handed spiral. The plate formula is Po, 3′, la, 6″, 5c, 4s, 5″′, 1″′. Thecadinium arenarium sp. nov. is somewhat wedge‐shaped in ventral view, photosynthetic with brownish chloroplasts and almost rounded in cross section. The cingulum forms a steep left‐handed spiral. The cell measures 35–41 μm in length and 25–30 μm in width. The thecal surface is weakly reticulated with small pores. The hypotheca is conical. The plate formula is Po, 3′, la, 6″, 5c, 4s, 5″′, 1″″.  相似文献   

20.
A new Grateloupia species from Luxun park, Qingdao Province, North China, was discovered during recent investigations and named Grateloupia serra H. W. Wang &; Y. Lou sp. nov. Morphological observations showed that: (1) the thalli were purple to dark red, cartilaginous and mucilaginous in texture, 15–45?cm in height; (2) the surface of thalli was covered with numerous proliferous branchlets and proliferous branchlets that were dentate when on the main axes; (3) the thalli were 450–550?µm thick, a cortex consisted of 6–8 layers of oblong or rounded cells and a medulla covered by compact medullary filaments; (4) the carpogonial branch was 6-celled and the auxiliary-cell branch was 5-celled, they were typical Grateloupia-type; (5) the internal structure of mature tetrasporangia were cruciately divided, oblong or square in shape. The morphological differences were supported by molecular analyses based on ribulose-1, 5-bisphosphate carboxylase/oxygenase gene (rbcL) sequences. Sequences of four G. serra sp. nov. samples were embedded into the Grateloupia clade and showed no pairwise divergence.  相似文献   

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