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1.
2.
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   

3.
Antarcticothamnion polysporum gen. et sp. nov. (Rhodophyceae: Ceramiaceae) is described from the South Shetland Is. and the Antarctic Peninsula. It differs from all previously described Ceramiaceae in vegetative structure: an indeterminate apex, which divides by alternating oblique septa, produces simple alternate-distichous determinate branches, while indeterminate branches are initiated on main axes in a verticillate arrangement. Reproductive structures are borne on modified indeterminate branch systems. Sporangia are polyhedrally divided. Spermatangia are formed in loose heads. Procarps are borne near the apex, but not always on the subapical cell, of a fertile branch. Two auxiliary cells may participate in the formation of a carposporophyte. A fusion cell is lacking and most cells of the gonimoblast develop into carposporangia, which are binucleate.

The suite of morphological characters exhibited by Antarcticothamnion sets this genus sufficiently apart from all previously described Ceramiaceae to warrant placement in its own tribe, Antarcticothamnieae trib. nov. It shares important features, however, with Callithamnieae, Compsothamnieae, and Ptiloteae.

Apical division is reviewed in the various tribes of Ceramiaceae. It is concluded that a pattern of alternating oblique septa is correlated with transitory or chronic structural imbalance resulting from a particular combination of timing and spatial sequence in the initiation and development of branches. The distribution of oblique apical division within Ceramiaceae is strongly correlated with features generally considered to be important at the level of tribe.

Phylogenetic relationships within Ptiloteae, a tribe characterized inter alia by oblique apical division, are suggested from an analysis of branching patterns. The validity of Falklandiella as a genus distinct from Dasyptilon is emphasized. Gymnothamnion and Tokidaea are removed from Ptiloteae, but without being assigned to another tribe. Tanakaella is removed from Sphondylothamnieae to Compsothamnieae, while Mazoyerella is removed from Compsothamnieae to Spermothamnieae.

Spongoclonium orthocladum A. et E. S. Gepp is discussed as a possible species of Antarcticothamnion, while an undescribed alga from the South Orkney Is. is definitely indicated as a second species of the genus.  相似文献   

4.
5.
Introduction. During a field excursion in Guizhou Province, China, we collected some interesting moss specimens with branch leaves subulate in the upper part, partially and variably bistratose laminae, and a Macromitrium-like epiphytic growth habit on tree trunks. We present morphological and phylogenetic arguments for recognising these plants as a new moss species in the genus Macromitrium Brid. (Orthotrichaceae).

Methods. We compared the morphology of the potential new species with closely related species of Macromitrium, and constructed a phylogenetic tree based on ITS2, trnL and trnG including sampling from 14 other morphologically similar species of Macromitrium.

Key results. The proposed new species belongs to the genus Macromitrium (Orthotrichaceae, Musci). It is closely related to M. gymnostomum Sull. & Lesq. in the phylogenetic tree and according to gametophytic morphological features, represents a hitherto undescribed species.

Conclusions. A new moss species, Macromitrium maolanense Zeyou Zhang, D.D.Li, Jing Yu & S.L.Guo, is described and illustrated. The new species can be distinguished from all congeners by the combination of the following features of the branch leaves: (1) oblong-lanceolate, lanceolate to linear-lanceolate, gradually narrowed to an easily broken subula; (2) rather obscure upper and medial cells, often with blackish stains among cells, densely pluripapillose; (3) variably and partially bistratose laminae in the upper 1/3 portion; (4) basal cells clear, hyaline and smooth, those near costae forming a ‘cancellina region’; and (5) with numerous brownish, clavate gemmae on upper portion. We also discuss the principal distinctive characters separating the new species from its nearest congeners.  相似文献   

6.
《Journal of bryology》2013,35(4):571-574
Abstract

Chains of 3–4-celled gemmae have been observed on the protonema of Trematodon brevicalyx, both in nature as well as in cultures. They are produced in abundance and may help in its survival, propagation and wide dispersal.  相似文献   

7.
《Journal of bryology》2013,35(3):241-244
Abstract

Fissidens subpulchellus Norkett in Gangulee is critically revised, and reduced to the synonymy of F. pulchellus Mitt. A new species, Fissidens longtonianus Z.Iwats. &; Tad.Suzuki, is described from India. This moss was collected on a branch in Jdukki District, South India, and is separated from F. pulchellus Mitt. by its smooth laminal cells, shorter setae and larger, smooth spores.  相似文献   

8.
Acrosymphyton firmum sp. nov., is described from the northeastern coast of North 1., New Zealand. Gametophytes are spring–summer annuals which grow subtidally on cobbles. Thalli are uniaxial; each axial cell bears a whorl of four indeterminate and one determinate branchlets. Indeterminate branchlets are alternately arranged giving the thallus a distichous and feather-like appearance. Numerous corticating rhizoidal filaments are produced from the periaxial and lower whorl branchlet cells. These rhizoids entwine and obscure the main axis as the thallus develops until in the mature plant the axes have a firm consistency and lubricous texture. The carpogonial branch bearing short lateral filaments and auxiliary cell branch with terminal auxiliary cell place this new species in the genus Acrosymphyton Sjöstedt. Of the three described species in the genus, A. firmum is most similar to A. taylori. This is the first report of the genus Acrosymphyton and the only confirmed report of the family Dumontiaceae in New Zealand waters.  相似文献   

9.
Two new propagule-farming red algae from southern Australia, Deucalion levringii (Lindauer) gen. et comb. nov. and Anisoschizus propaguli gen. et sp. nov., are described and defined largely on their development in laboratory culture. Deucalion is included in the tribe Compsothamnieae on the basis of its subapical procarp and alternate distichous branching. It differs from the other genera included in that tribe in that it produces 3-celled propagules, polysporangia, a subapical cell of the fertile axis which bears 3 pericentral cells, and an apparently post-fertilization involucre which develops from the hypogenous and sub-hypogenous cells of the fertile axis. Its gametophyte morphology has been elucidated in culture, as only sporophytes are known from the field. Gametophytes do not appear to produce propagules. Anisoschizus is provisionally included in the tribe Spermothamnieae on the basis of its subdichotomous branching, possession of a prostrate system and the production of polysporangia. It differs from the other genera of the tribe in the production of 2-celled propagules. Observations on the germination of the “monosporangia” of Mazoyerella arachnoidea and Monosporus spp. indicate that they are analagous to the propagules of Deucalion and Anisoschizus. The nature of these propagules and their role in recycling the parent plant are discussed and contrasted with true monosporangia. It is recommended that Monosporus be maintained as a form genus containing representatives from more than one tribe, as exemplified by plants from Lord Howe I. provisionally identified as M. indicus Boergesen which have both prostrate and erect, as opposed to only erect, axes.  相似文献   

10.

A parasitological survey searching diplectanids (Monogenea: Diplecatnidae) infesting the gills of marine fishes from South America was carried out during the 2019–2020 period. The gills of four sciaenid species, 2 Cheilotrema fasciatum Tschudi, 1 smalleye croaker Nebris microps Cuvier, 2 royal highhat Pareques lanfeari (Barton), and 1 minor stardrum Stellifer minor (Tschudi), were sampled. Six new species of Rhamnocercus Monaco, Wood & Mizelle, 1954 were described: Rhamnocercus chacllae n. sp. and Rhamnocercus chaskae n. sp. from P. lanfeari, Rhamnocercus fasciatus n. sp. from C. fasciatum, Rhamnocercus microps n. sp. from N. microps, and Rhamnocercus rimaci n. sp. and Rhamnocercus tantaleani n. sp. from S. minor. Rhamnocercus chacllae n. sp. can be differentiated from its congeners by its L-shaped male copulatory organ (MCO) and by having an anteromedial slight notch at ventral bar. Rhamnocercus chaskae n. sp. differs from the other species of the genus by its long and straight MCO with bifid distal end and by having haptoral accessory spines at level of ventral bar with quadrifid distal portion. Rhamnocercus fasciatus n. sp. is characterized by possessing a straight and long MCO with truncated distal end, haptoral accessory spines at level of ventral bar with bifid distal portion, dorsal bars with a knob at lateral extremity, and a large vagina with bell-shaped. Rhamnocercus microps n. sp. differs from all congeners mainly by having a short and straight MCO with the distal end of internal tube spatulate and uncovered by external tube. Rhamnocercus rimaci n. sp. is can be distinguished from all other species of Rhamnocercus by having an almost J-shaped MCO with the distal end of external tube slight expanded and the distal end of internal tube narrow and uncovered by external tube. Rhamnocercus tantaleani n. sp. is mainly characterized by its MCO, which is tubular and straight, having the distal end of external tube bifurcated (right branch well-expanded and left branch narrow) and the distal end of internal tube enveloped by left branch of the external tube. This is the first data on the parasites of P. lanfeari, a little known, but popular fish in local markets from Peru. Rhamnocercus microps n. sp. is the first described species of Rhamnocercus in Brazil. The present finding brings to 12, the number of known species of Rhamnocercus. A key to Rhamnocercus species is provided.

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11.
《Journal of bryology》2013,35(4):613-620
Abstract

Sphagnum olafii (Sect. Acutifolia) sp. nov. can be recognized in the field by its soft appearance, its brownish capitula with often a faint lustre of purple-red, by a variegated, pale and brownish stem and lingulate-triangular stem leaves. Microscopically, it is recognized by the occurrence of scattered pores in the surface cells of the stem cortex, and markedly bulging hyalocysts on the convex surface of the branch leaves with narrow, wedge-shaped exposures to the chlorocysts. The new species shows closest affinity to S. arcticum Flatb. & Frisv. It is reported from four localities in Svalbard.  相似文献   

12.
Three intertidal sites dominated by Corallina turfs were investigated in Hokkaido, Japan. The sites (A, B and C) differed in slope, wave exposure and length of time exposed to air during tidal cycles. Monthly samples were analyzed for frond morphology and other features. Site A, the most wave-exposed site, was dominated by Corallina sp. X, an unknown species, and sites B and C by Corallina pilulifera Postels et Ruprecht. At the different sites the populations differed in conceptacle abundance, coverage by epiphytic Titanoderma corallinae (P. Crouan et H. Crouan) Woelkerling, Chamberlain et Silva, amount of contained sediment, numbers of axes per quadrat, numbers of branch fusions, branch entanglement, frond dryweight, frond length, amount of adventitious branching, numbers of epiphytes (exclusive of T. corallinae), and numbers of animal species. Ninety-one animal species were recorded from the turfs. Corallina is affected morphologically by conditions inherent in its microhabitat, including desiccation, epiphyte loading and the abundance of herbivores.  相似文献   

13.
Abstract

The anthers are tetrasporangiate. The anther wall comprises epidermis, fibrous endothecium, middle layer and tapetal layer. The tapetum is of the Glandular type and its cells remain uninucleate. Meiosis in pollen mother cells is normal and simultaneous cytokinesis leads to the formation of tetrahedral and decussate microspore tetrads. The pollen grains are shed at 2-celled stage. The ovule is campylotropous, bitegmic and crassinucellate. Meiosis in megaspore mother cell results in the formation of linear or occasionally T-shaped megaspore tetrad. The chalazal megaspore develops into Monosporic Polygonum type of embryo sac. Endosperm development is of the Nuclear type.  相似文献   

14.
A new species of Gelidiocolax Gardner, G. pustulata Oliveira and Yoneshigue, is described in the tropical western Atlantic from Brazil. The species usually grows on the basal portion of the main axis of Pterocladia capillacea (Gmelin) Bornet et Thuret. Abundant material was collected mainly from November to March at Cabo Frio Island, in the northeast part of the State of Rio de Janeiro, a marine area well known for its upwelling. Infection by the putative parasite seems to damage the host tissue, stimulating the development of a “gall-like” structure that leads to the outgrowth of adventitious branches. The new species has the vegetative features and reproductive structures of the genus Gelidiocolax. It can be distinguished from the other Gelidiocolax species mainly on the basis of its position on the host, size of pustula, the tetrasporangia and the development of spermatangia. Studies of this new taxon support the placement of Gelidiocolax in the Gelidiaceae and not the Choreocolacaceae, as has been suggested in the literature.  相似文献   

15.
16.
Turbinaria foliosasp. nov. is described on the basis of several collections made from Dhofar, Sultanate of Oman. The new species is known only from southern Oman, a region of the northern Arabian Sea that is strongly impacted by the upwelling from the summertime monsoon. It is distinguished from other species of the genus by the shape of the leaves and by their loose, non‐congested arrangement. Air vesicles, embedded in the leaves, may be present, but more often are absent. A census of the currently recognized species in the genus Turbinaria is provided. Reference is made to Sargassum turbinarioides and Sargassum turbinati‐folium. These species possess discrete blades and spherical vesicles and thus conform to Sargassum.  相似文献   

17.
《Journal of bryology》2013,35(4):435-441
Abstract

S. subsecundum Nees and S. auriculatum Schimp. are distinct species which can always be separated when well grown. Poorly grown S. auriculatum can resemble S. subsecundum, but can almost invariably be distinguished by careful selection of the larger stem leaves in any gathering. When the size of both stem and branch leaves is taken into account, confusion can hardly ever arise, even with depauperate forms. S. inundatum Russ. is not specifically distinct from S. auriculatum, and is recombined as S. auricula tum Schimp. var. inundatum (Russ.) M. O. Hill.  相似文献   

18.

In 59 samples of periphyton and phytoplankton collected in 2002 - 2003 from the Nahal Qishon (Qishon River), northern Israel, we found 178 species from seven divisions of algae and cyanoprocaryotes. Diatoms, clorophytes, and cyanoprocaryotes prevail. Nitzschia and Navicula (Bacillariophyta) are the most abundant. Most of the species are cosmopolitan or widespread, except Lagynion janei (Chrysophyta), which is endemic for the Mediterranean Realm. About 17% of species (26) are new for Israel and five of them represent the first recorded genera: Crinalium endophyticum Crow, Actinocyclus normanii (Gregory) Hustedt, Rhizoclonium hieroglyphicum (Agardh) Kütz (Chlorophyta), Lagynion janei Bourelly, and Stylococcus aureus Chodat. Most of them come from a rare riverine assemblage with red alga Audouinella pygmea, as well as from the estuarine assemblage. Alkaliphiles predominate among the indicators of acidity, with few acidophiles confined to the communities under the impact of industrial wastes. Among the indicators of salinity, most numerous are the oligohalobien-indifferents and species adapted to a moderate salinity level. The relative species richness of ecological groups and the indices of saprobity are correlated with changes in conductivity, pH, and N-nitrate concentration. Indicators of organic pollution fall in the range of betameso- to alfamesosaprobic self-purification grades. Our studies show ecological significance of the Nahal Qishon as a model for a strongly disturbed aquatic ecosystem in the coastal zone of eastern Mediterranean.  相似文献   

19.
A new species, Halimeda hummii, and a new variety of Halimeda cryptica Colinvaux and Graham both originally collected from the edge of the continental shelf on the southwest coast of Puerto Rico are newly described. The new species is irregular in its segment morphology and is the smallest species of Halimeda presently known. Halimeda cryptica var. acerifolia from deep water possesses distinctive segments resembling maple leaves. Halimeda copiosa Goreau and Graham and typical H. cryptica are also collected in deep water and are newly recorded from Puerto Rico.  相似文献   

20.
Abstract

Rhynchostegium confusum, a new species from Spain and the Iberian Peninsula is described. It is closely related to R. confertum, from which it differs in its noticeably wider stem leaves with wider and apically spurred costa, more flexuous branch leaves, and shorter seta. It also differs in its habit and habitat: the plants are tightly attached to siliceous rocks just over the water level in rivulets that dry out during the summer in the Mediterranean region. Molecular data show that the new species derives from R. confertum, but is clearly differentiated from the studied populations of the latter in a number of missing haplotypes.  相似文献   

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