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1.
Observations are made on the occurrence and distribution of the red algal genus Hypoglossum Kützing (Delesseriaceae, Ceramiales) in the tropical western Atlantic. In addition to the type of the genus, H. hypoglossoides (Stackh.) Coll. & Herv., three other species are reported: H. anomalum sp. nov., H. involvens (Harv.) J. Ag., and H. tenuifolium (Harv.) J. Ag. A key is presented to distinguish these four species. The newly described species, H. anomalum, is like other species in the genus in that its branches arise endogenously from the primary axial row but it is unique in that the branches emerge from the parent blade at some point between the midline and the margin of the blade. The new species is reported from Puerto Rico and Florida.  相似文献   

2.
A giant form of Anadyomene, most similar to Anadyomene pavonina (J. Agardh) Wille, a rare and diminutive alga endemic to Florida, appeared as up to 10 m long net‐like strands covering 10%–80% of a 0.5 km region of the 25–50 m deep Belizean outer reef slope where none had been present up to 12 months earlier. This new species, described herein as Anadyomene gigantodictyon Littler et D. S. Littler, is characterized by a unistratose blade or cluster of blades formed by the polychotomous branching of uniseriate veins, with the interstices, or spaces between the veins, completely or partially filled with cells that are smaller than those of the veins, with cylindrical to ovate cells. The cells at mid‐blade are 1.7–2.0 mm in length and 0.2–0.3 mm diameter; interstitial cells are parallel and not juxtaposed. All cells are joined in one plane and form species‐specific, fan‐shaped patterns with secondary interstitial cells loosely or tightly woven.  相似文献   

3.
The new genus Pycnococcus Guillard is based on several clones from the western North Atlantic and Gulf of Mexico. The type and only described species, Pycnococcus provasolii Guillard, sp. nov., is typified by clone Ω48-23 from the North Atlantic. Cells of Pycnococcus provasolii are solitary, spherical, 1.5–4.0 μm in diameter, have a resistant cell wall lacking sporopollenin, and have the ultrastructural characteristics of green algae. With the light microscope they are scarcely distinguishable from cells of other coccoid planktonic organisms. In pigmentation P. provasolii resembles Micromonas pusilla, Mantoniella squamata, and Mamiella gilva in having chl a, much chl b, Mg 2,4-divinylphaeoporphyrin a5 monomethyl ester (presumably), and prasinoxanthin as a major xanthophyll. The pyrenoid of P. provasolii has a cytoplasmic channel, which is unique among species closely related to it. Flagellates, occurring rarely in culture, are similar to but distinguishable from known Pedinomonas species by size and shape. Pycnococcus provasolii is referred to the new family Pycnococcaceae Guillard, in the order Mamiellales of the class Micromonadophyceae (Chlorophyta). Clones of Pycnococcus provasolii are oceanic in nutritional characteristics, require only vitamin B12 in culture, and are well adapted to growth under blue or blue-violet light of low intensity.  相似文献   

4.
Five Ceramiaceae (Rhodophyta) are reported from the offshore waters of the southeastern, warm temperate coast of the United States. These include two new monotypic genera, Calliclavula trifurcate Schneider in the Griffithsieae and Nwynea grandispora Searles in the Sphondylothamnieae, and three new species, Callithamniella silvae Searles, Ptilothamnion occidentale Searles, and Lejolisia exposita Schneider et Searles.  相似文献   

5.
Cryptomonads are a ubiquitous and diverse assemblage of aquatic flagellates. The relatively obscure genus Hemiselmis includes some of the smallest of these cells. This genus contained only two species until 1967, when Butcher described seven new marine species mainly on the basis of observations with the light microscope. However, from these seven taxa, only H. amylifera and H. oculata were validly published. Additionally, the features Butcher used to distinguish species have since been questioned, and the taxonomy within Hemiselmis has remained clouded due to the difficulty in unambiguously applying his classification and validating many of his species. As a result, marine strains are often placed into one of three species—H. rufescens Parke, H. virescens Droop, or the invalid H. brunnescens Butcher—based on cell color alone. Here we applied microscopic and molecular tools to 13 publicly available Hemiselmis strains in an effort to clarify species boundaries. SEM failed to provide sufficient morphological variation to distinguish species of Hemiselmis, and results from LM did not correlate with clades found using both molecular phylogenetic and nucleomorph genome karyotype analysis, indicating a high degree of morphological plasticity within species. On the basis of molecular characters and collection geography we recognize four new marine species of HemiselmisH. cryptochromatica sp. nov., H. andersenii sp. nov., H. pacifica sp. nov., and H. tepida sp. nov.—from the waters around North America.  相似文献   

6.
1975年和1987年分别在湖南宜章和云南景东采到角蟾属Megophrys标本2种。经与角蟾属已知种对比,特别是与相近种白颌大角蟾M.lateralis(Anderson)在外部形态和头骨特征方面的深入研究,其差异明显,被确定为2新种,即莽山角螗M.mangshanensis和腺角蟾M.glandulosa。本文对2新种的形态和生态资料作了记述。  相似文献   

7.
The volvocacean genus Pleodorina has been morphologically characterized as having small somatic cells in spheroidal colonies and anisogamous sexual reproduction with sperm packets. In this study we examined two new species that can be assigned to the genus Pleodorina based on morphology: P. starrii H. Nozaki et al. sp. nov. and P. thompsonii F. D. Ott et al. sp. nov. P. starrii was collected from Japan and had 32‐ or 64‐celled colonies with anterior somatic cells and spheroidal individual cellular sheaths that were weakly attached to each other within the colonial envelope. P. thompsonii from Texas (USA) exhibited four or 12 somatic cells in the anterior pole of 16‐ or 32‐celled colonies, respectively, and had a single large pyrenoid in the chloroplast of mature reproductive cells. The chloroplast multigene phylogeny placed P. starrii and P. indica (Iyenger) H. Nozaki in a clade that was robustly separated from the type species P. californica Shaw and P. japonica H. Nozaki. Pleodorina thompsonii was resolved as a basal branch within a large monophyletic group (Eudorina group) composed of Eudorina, Pleodorina and Volvox (excluding section Volvox). Thus, Pleodorina was found among three separate lineages within the Eudorina group in which Eudorina and Volvox were also resolved as nonmonophyletic. The DNA sequences from additional species/strains as well as recognition of morphological attributes that characterize the monophyletic groups within the Eudorina group are needed to construct a natural generic classification within these members of the Volvocaceae.  相似文献   

8.
Some Liagora and Izziella distributed in Taiwan display a wide range of morphological variation and can be difficult to distinguish. To clarify species concepts, we applied DNA sequence analyses and examined carposporophyte development in detail. These studies revealed two new species, which are described herein as Izziella hommersandii sp. nov. and Izziella kuroshioensis sp. nov. I. kuroshioensis superficially resembles Izziella formosana and Izziella orientalis in that its involucral filaments subtend rather than surround the lower portion of the gonimoblast mass (= Izziella type) and a fusion cell is formed from cells of the carpogonial branch, but it can be separated by differences in the cell numbers and branching pattern of the involucral filaments, as well as thallus morphology. In contrast to other species that also bear short lateral branchlets, I. hommersandii is unique in possessing a mixture of short and long involucral filaments, a phenomenon not reported before. The length of the involucral filaments is species specific among species of Izziella and contrasts to the behavior of the involucral filaments after fertilization in species such as “Liagorasetchellii [= Titanophycus setchellii comb. nov.], in which the filaments completely envelop the gonimoblast. In addition, the cells of the carpogonial branch in Titanophycus do not fuse after fertilization to form a fusion cell. Thus, a combination of characters with respect to the behavior of the carpogonial branch and the involucral filaments after fertilization is very useful for delineating species boundaries in Izziella and for separating Titanophycus from Izziella and Liagora.  相似文献   

9.
描述了湖南零陵普利桥晚泥盆世锡矿山组叶虾类一新种——Echinocaris hunanensis sp.nov..晚古生代叶虾类化石较为稀少,Echinocaris在亚洲是首次发现.  相似文献   

10.
本文记述采自安徽含山熔洞的一米虾新种——含山米虾Caridina hanshanensis sp. nov.本新种与近缘种秉氏米虾C. pingi Yu有不同,故订为新种。  相似文献   

11.
本文报道了鲤科鳅(鱼它)属鱼类一新种,定名为少耙鳅(鱼它)Gobiobotia paucirastella。和近似种裸胸鳅(鱼它)Gobiobotia tungi相比,该新种胸腹部裸露区较大,鳃耙与侧线鳞较少。  相似文献   

12.
记中国辽宁西部九佛堂组发现的中国翼龙一新种   总被引:10,自引:0,他引:10  
根据发现于辽宁省西部下白垩统九佛堂组的—小型翼手龙类骨架,建立一新种:谷氏中国翼龙Sinopterus gui sp.nov.。它的吻端直而尖锐,其下颌发育—明显的脊突。肱骨的三角脊发育,其末端没有扩展,呈四边形。翼掌骨的长度稍微短于飞行指第一指节的长度。股骨与胫骨之比率小,乌喙骨短于肩胛骨,联合背椎只有椎体相互愈合。虽然它与董氏中国翼龙相似,但是存在明显区别,比如个体较小,而大多数背椎椎体相互愈合等。谷氏中国翼龙是目前在辽西及其周边地区所发现最小的没有牙齿的翼手龙类。  相似文献   

13.
Morphological and molecular studies, as well as original literature reexamination, necessitate establishment of five Euglena species with a single axial, stellate chloroplast [Euglena viridis (O. F. Müller) Ehrenberg 1830 , Euglena pseudoviridis  Chadefaud 1937 , Euglena stellata  Mainx 1926 , Euglena pseudostellata sp. nov., and Euglena cantabrica  Pringsheim 1956 ], three species with two chloroplasts (Euglena geniculata Dujardin ex Schmitz 1884 , Euglena chadefaudii  Bourrelly 1951 , and Euglena pseudochadefaudii sp. nov.), and one species with three chloroplasts (Euglena tristella  Chu 1946 ). The primary morphological features, allowing distinction of the considered species are the presence and the shape of mucocysts, as well as the number of chloroplasts. Spherical mucocysts occur in E. cantabrica and E. geniculata, while spindle‐shaped mucocysts are present in E. stellata, E. pseudostellata, E. chadefaudii, E. pseudochadefaudii, and E. tristella. No mucocysts are observed in E. viridis and E. pseudoviridis. Two new species (E. pseudochadefaudii sp. nov. and E. pseudostellata sp. nov.) differ from the respective species, E. chadefaudii and E. stellata, only at the molecular level. Molecular signatures and characteristic sequences are designated for nine distinguished species. Emended diagnoses for all and delimitation of epitypes for seven species (except E. viridis and E. tristella) are proposed.  相似文献   

14.
蠕形螨属一新种(真螨目:蠕形螨科)   总被引:1,自引:0,他引:1  
本文报道采自大熊猫AiluroPoda melanoleuca眼脸皮肤及眼睫囊内寄生的一种蠕形螨——大熊猫蠕形螭Demodex ailuro podae,新种。  相似文献   

15.
云南省蚱科一新属新种(直翅目:蚱科)   总被引:4,自引:0,他引:4  
本文报道蚱科一新属一新种。新属,微翅蚱属Alulatettix gen nov.的主要特征是前胸背板强烈隆起呈屋脊形,前胸背板侧片后缘具二凹陷,前、后翅甚微小。其模式种为云南微翅蚱Alulatettix yunnanensis sp.nov.  相似文献   

16.
17.
本文报道松塔牛肝菌属四个新种,即:裸皱松塔牛肝菌Strobilomyces gla-bellus Ying sp.nov.,阔裂松塔牛肝菌S.latirimosus Ying sp.nov.,微茸松塔牛肝菌S.subnudus Ying sp.nov.,短绒松塔牛肝菌S.velutinus Ying sp.nov.;及四个中国新记录种,即:柔鳞松塔牛肝菌S.mollis Corner,疣鳞松塔牛肝菌S.nigricans Berk.,锥鳞松塔牛肝菌S.polypyramis Hook.,半裸松塔牛肝菌S.semi-nudus Hongo.松塔牛肝菌属Strobilomyces以其具有变黑的担子果与菌幕、不粘的菌盖上有疣状、绵绒状或刺状鳞片以及黑褐色带明显纹饰的孢子而易于识别。Singer(1945)按孢子纹饰的不同将松塔牛肝菌属分为两个组,其一为具疣、刺和网纹的种类;另一为具纵贯孢子两端的翼状棱纹的种类。对于后者的归属问题,Pegler & Young持不同见解,并于1981建立了非洲牛肝菌属AfroboletusPegler & Young以纳孢子具翼状纵棱和孢缘边(rim)的种类;含2—4种,分布在非洲近赤道的地区。在中国,松塔牛肝菌属已报道过三个种,即:松塔牛肝菌Strobilomyces,floc-copus(Vahl.ex Fr.)Karst.光头松塔牛肝菌S.glabriceps Chiu和混淆松塔牛肝菌S.confusus Sing.。裘维蕃(1948,1957)曾描述过网孢松塔牛肝菌Strobi-lomyces retisporus(Pat.et Bak.)Gilb.但因其子实体色鲜红至褐红而不变黑色、子层体淡暗黄色且菌肉不变红-黑色、孢子具网纹而宜转隶于Heimiellia Boedijn(1951)。文中有新分类单位和国内已知种的分种检索表、新种的拉丁文和英文描述并有绘图和扫描电镜照片示明孢子纹饰。  相似文献   

18.
A new ceramiaceous alga, Sciurothamnion stegengae De Clerck et Kraft, gen. et sp. nov., is described from the western Indian Ocean and the Philippines. Sciurothamnion appears related to the tribe Callithamnieae on the basis of the position and composition of its procarps and by the majority of post‐fertilization events. It differs, however, from all current members of the tribe by the presence of two periaxial cells bearing determinate laterals per axial cell. Additionally, unlike any present representative of the subfamily Callithamnioideae, no intercalary foot cell is formed after diploidization of the paired auxiliary cells. The genus is characterized by a terminal foot cell (“disposal cell”), which segregates the haploid nuclei of the diploidized auxiliary cell from the diploid zygote nucleus. The nature of three types of foot cells reported in the Ceramiaceae (intercalary foot cells containing only haploid nuclei, intercalary foot cells containing haploid nuclei and a diploid nucleus, and terminal foot cells containing only haploid nuclei) is discussed.  相似文献   

19.
Three new benthic, sand-dwelling dinqflagellate species, Prorocentrum sabulosum, Prorocentrum scuptile, and Prorocentrum arenarium, from coral rubble are described from scanning electron micrographs. Species were identified based on shape, size, surface micromorphology, ornamentation of thecal plates, and architecture of the periflagellar area and intercalary band. Cells of P. sabulosum are oval with a cell size of 48–50 μm long and 41–48 μm wide. The areolae are round to oval and numerous (332–450 per valve) and range from 1 to 1.6 μm in size. The periflagellar area of P. sabulosum bears a wide V-shaped depression with a flat ridge and lacks ornamentation; it accommodates six pores: one large flagellar pore, an adjacent smaller auxiliary pore, and four pores of unknown function. The flagellar and auxiliary pores are surrounded by a narrow apical collar. The intercalary band of P. sabulosum is smooth. Prorocentrum sculptile cells are broadly oval, 32–37 nm long, and 30–32 μm wide in valve view with a deep-sculptured apical area. The valves are smooth and are marked with shallow depressions (856–975 per valve). Some of these depressions have a small round opening (0.13 μm in diameter). The periflagellar area is V-shaped with a deeply indented depression; it accommodates the two flagella and a thin angled apical plate. The intercalary band is smooth. Prorocentrum arenarium cells are nearly round in valve view 30–32 μm in diameter. Thecal surface is smooth with scattered kidney-shaped valve poroids (65–73 per valve) and marginal poroids (50–57 per valve). Length and width of poroids are 0.62 μm and 0.36 μm, respectively. The periflagellar area is an unornamented, broad triangle into which a large flagellar pore and a smaller auxiliary pore are fitted. Both flagella, longitudinal and transverse, protrude from the flagellar pore. The intercalary band is smooth. The presence of a peduncle-like structure (2–3 μm long) in P. arenarium was observed situated in the flagellar pore.  相似文献   

20.
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