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1.
Twenty-five freshwater populations of Ceramiales were collected in North America, 24 of which were from the tropical rainforest region of Central America and the Caribbean. The streams tended to be moderate in mean current velocity (X?= 23.3 cm·S?1) and maximum width (X?= 6.3 m) but high in temperature (X?= 23.1°C), pH (X?= 7.9), and specific conductance (X?= 320 μS·cm?1). Three Bostrychia species were restricted to the Caribbean islands: B. moritziana (Sonder ex Kütz.) J. Ag. (syn. B. cornigera Mont. and B. radicans f. moliforme Post), with ecorticate indeterminate axes, monosiphonous ultimate branches, and cladohaptera; B. radicans (Mont.) Mont. (syn. B. leprieurii Mont and B. rivularis Harv.), with ecorticate and polysiphonous axes throughout and cladophaptera; and B. tenella (Lamour.) J. Ag., with corticate indeterminate axes, monosiphonous ultimate branches, and peripherohaptera. Ballia prieurii Kütz. was found in Belize and Costa Rica and was characterized by rebranched determinate laterals, opposite branching, and long apical cells (X?= 61 μm) and axial cells (X?= 43 μm). Caloglossa leprieurii (Mont.) J. Ag. was localized in Puerto Rico while. C. ogasawaerensis Okam. was collected only in Costa Rica. The two species were separated by site of branching (midrib vs. margin) and blade width (X?= 384 vs. 861 μm). Polysiphonia subtilissima Mont. from Florida and Jamaica had four pericentral cells, no cortication, rhizoids arising from pericentral cells, and branches initiated at trichoblast scars.  相似文献   

2.
The temperature tolerances of 24 tropical macroalgae collected on Hainan Island (P.R. China) were investigated. For some isolates, growth response curves were also determined. The upper survival temperatures (USTs, 32–37°C) of these tropical west Pacific strains are similiar to those of tropical Atlantic species. With regard to their lower survival temperatures (LSTs) the species investigated show high variations: 12 species have LSTs between 16 and 7°C (Hypnea musciformis (Wulfen) Lamx. var esperi J, Ag., Centroceras clavulatum (C. Ag) Mont., Falkenbergia hillebrandii (Bornet) Falkenberg, Gelidiopsis intricata (Ag.) Vickers, Halymenia maculata J. Ag., Hypnea cenomyce J. Ag., Hypnea spinella (C. Ag.) Kütz., Gracilaria changii (Xia et Abott) Abott, Chang et Xia, Dictyopteris repens (Okam.) Boerg., Laurencia cartilaginea Yamada, Gelidium pusillum (Stackh.) Le Jol., Laurencia sp.). Their LSTs and temperature requirements for growth (range: 15–30 °C, optimum: 25–30 °C) are mostly similar to those of tropical west Atlantic and amphi-Atlantic (sub)tropical macroalgae as well as to tropical isolates of species with an Atlantic tropical to warm-temperate distribution. The remaining 12 species have LSTs between 6 and 1 °C (Ulva conglobata Kjellm., Ulva fasciata Delile, Padina boryana Thivy, Dictyosphaeria cavernosa (Forssk.) Boerg., Boodlea composita (Harv.) Brand, Boergesenia forbesii (Harv.) Feldm., Cladophora vagabunda (L.) van den Hoek, Enteromorpha compressa (L,) Grev., Enteromorpha intestinalis (L.) Link, Gracilaria tenuistipitata Chang et Xia, var liui Chang et Xia, Monostroma nitidum Wittr. and Valonia aegagropila C. Ag.). Their LSTs are mostly similar to those of Atlantic macroalgae with a tropical to (warm-) temperate distribution. The results are discussed with respect to the factors which may have triggered the development of the temperature requirements of the various species.  相似文献   

3.
海南兰科植物新资料   总被引:2,自引:0,他引:2  
报道了中国兰科Orchidaceae植物一新记录属和3个中国新记录种及5个海南新记录种。其中小囊兰属Micropera Lindl.、红花小囊兰Microperapoilanei(Guill.)Garay、疏花羊耳蒜Liparis sparsiflora Aver.和美丽云叶兰Nephelaphyllum pulchrum Bl.为中国新记录;平卧曲唇兰Panisea cavalerei Schltr.、云南曲唇兰Panisea yunnanensis S.C.Chen&Z.H.Tsi、束花石斛Dendrobium chrysanthum Wallichex Lindl.、滇南翻唇兰Hetaeria rubens (Lindl.)Benth.ex J.D.Hook.f和毛叶芋兰Nervilia plicata(Andrews)Schltr.为海南新记录种。  相似文献   

4.
The morphology, ecology, cytology and systematics of Acrochaetium botryocarpum (Harv.) J. Ag. have been studied. This species occurs throughout the year in southern Australia and grows on a variety of hosts. The variable appearance of the prostrate system results from the effect of the substratum upon its morphology. Plants reach a height of 6 mm; cells of the erect filaments contain a single chromoplast with a variable number of pyrenoids. Tetrasporangial plants occur mainly in winter and sexual plants occur mainly in spring and early summer; the two generations are isomorphic. Stages of fertilisation have been observed and photographed. Acrochaetium polyrhizum (Harv.) J. Ag. is referred to the synonomy of A. botryocarpum, and A. codicolum Brg., A. grande (Levr.) De Toni fil. and A. rhizoideum (Drew) Sm. are regarded as probable synonyms. This study of A. botryocarpum indicates that host specificity, substrate relations, form of spermatangia and immediate post-fertilisation activity may not be as reliable as formerly thought for making taxonomic distinctions within the Acrochaetium-Rhodochorton complex.  相似文献   

5.
VENTER, H.J. T. & FIELD, D. V., 1989. A new species of Stomatostemma (Periplocaceae) from Mozambique, Africa. A new species of Stomatostemma is described from Mozambique. 11 is [he second species distinguished in the genus Stomatostemma N.E. Br., the other being S. monteiroae (Oliv.) N.E. Br., which was also described from Mozambique. The new species is distinguished from.V. monteiroae by being a virgate shrub, by the pendulous terminal branches and inflorescences, by the long and frail peduncles and pedicels and by the long clavate corona lobes.  相似文献   

6.
Abstract— The genus Pegolettia (Compositae, Inuleae) from Africa, Arabia, and the Middle East is revised. The nine recognized species, viz. P. lanceolata Harv., P. baccaridifolia Less., P. gariepina A. Anderb., P. oxyodonta DC., P. retrofracta (Thunb.) Kies, P. tenuifolia Bolus, P. plumosa M. D. Hend., P. pinnatilobata (Klatt) O. Hoffm. ex Dinter, and P. senegalensis Cass., are treated cladistically, and a cladogram is presented. The species are illustrated, and their distributions mapped. Hypotheses on the mode of speciation and the biogeography of the group including a model of area relationships in southern Africa are presented.  相似文献   

7.
8.
中国杏属一新种   总被引:5,自引:1,他引:4  
描述了中国杏属一新种,华仁杏(Armeniaca cathayanaD.L.Fu,B.R.Li et J.H.Li,sp.nov.)。该新种与杏(Armeniaca vulgarisLam.)和山杏(A.sibirica(L.)Lam.)相似,但又有其独特特征,主要区别如下:叶两面疏被短柔毛,边缘具单锯齿和重锯齿,基部全缘;叶柄无腺体;单花或2~3朵花簇生;子房密被白色长柔毛;果核三角状卵球形,腹缝线具5~7条锐纵棱,背缝线具1条浅纵沟;种子大,两侧压扁,种仁质脆,无苦味。该新种由傅大立于2008年7月11日在河北省涿鹿县发现并采集,模式标本存于中国林业科学研究院(CAF),标本号:No.2008071101。  相似文献   

9.
Three members of the red algal family Halymeniaceae (Thamnoclonium dichotomum (J. Ag.) J. Ag., Codiophyllum flabelliforme (Sond.) Schmitz, and C. decipiens (J. Ag.) Schmitz) are investigated. All are endemic to southern and southwestern Australia, possess basal stalks of substantial size and firmness, and are consistently associated with specific sponge taxa. In each case, the sponges are bonded by collagen-like fibrils to the host cuticle without modifying the algal tissue at the ultrastructural level. Secondary cortication and prominent growth rings occur in the stalks of all three species, and in each the pit plugs between cells become wider, more convoluted and less electron dense with increasing distance from the surface. Such pit plugs are apparently a unique attribute of the stalked Halymeniaceae. The three species share pit plug, sponge association and stalk morphological features but are not otherwise closely related, as they actually represent three distinct genera.  相似文献   

10.
New data on synonymy and typification of Dasya species of the western Mediterranean are provided, including: D. baillouviana (S. G. Gmel.) Mont., D. corymbifera J. Agardh, D. hutchinsiae Harv., D. ocellata (Gratel.) Harv., D. rigescens Zanardini, D. rigidula (Kütz.) Ardiss., D. sessilis Yamada and D. punicea (Zanardini) Menegh. in Zanardini. Data on synonymy and a brief nomenclatural story are shown for each species, a lectotype and a neotype are selected respectively for D. rigidula and D. punicea and clarification of neotype designation is discussed for D. corymbifera.  相似文献   

11.
《Journal of bryology》2013,35(3):193-194
Abstract

The relationships within the Bryaceae, with emphasis on the genus Bryum, were studied based on morphological and anatomical characters and using cladistic methods. The analysis was performed with thirty-six species representing the different parts of the family, and with Funaria hygrometrica Hedw., Mnium hornum (Dicks.) Lindb., and Tayloria lingulata Hedw. as outgroups. The Bryaceae, and the subfamilies Bryoideae, Mielichhoferioideae, and Pohlioideae, as defined by several earlier authors appear to be paraphyletic. The genus Bryum seems to be paraphyletic, because Leptobryum pyriforme (Hedw.) Wils., Osculatia columbica De Not., and Rhodobryum giganteum (Schwaegr.) Paris, appear as ingroups within this genus when the tree is rooted with Funaria. Mnium hornum came out as the sister taxon of a clade including Pohlia cruda (Hedw.) Lindb. and P. longicollis (Hedw.) Lindb., whereas P. drummondii (Müll. Hall.) A.L. Andrews, appears not to be closely related to the other two Pohlia species studied here, making this genus paraphyletic. Mielichhoferia mielichhoferiana (Funck.) Loeske, appears as the sister taxon of Schizymenium bryoides Harv., suggesting that both these genera are paraphyletic. Overall, the stabilities of the clades are low and it is suggested that combined analyses of morphological, anatomical, and molecular data are needed to get better resolved and more stable trees.  相似文献   

12.
Within South African Asteraceae-Anthemideae there is a group of genera containing furanosesquiterpenes rather than the common polyacetylenes. Of these genera, Asaemia (Harv.) Ham. ex Benth. & Hook., Athanasia L., Eumorphia DC., Gymno-pcnfzia Benth., Phymaspermum Less. and Sfilpnophyfon Less. have been investigated morphologically especially with respect to fruit structure. As a result of the investigations Stilpnophyton has been reduced to synonomy under Athanasia L. emend. Källersjö (with 36 spp.) and five species of Athanasia , together with Phaeocephalus S. Moore., are placed in the revived genus Hymenolepis Cass. (with 7 spp.). Brachymerk DC. and four misplaced species of Aihanasia are included in Phymaspermum Less. emend. Källersjö (with 17 spp.). Nine other misplaced species of Athanasia and one Pentzia Thunb. species have been described as a new genus Inulanihera Källersjö (with 10 spp.), a group without furanosesquiterpenes. The two monotypic genera Asaemia and Gymnopentzia , and Eumorphia (with 6 spp.) remain unchanged. The interrelationships of the genera possessing furanosesquiterpenes are shown in a cladogram. There are 25 new combinations in Afhanasia, Znulanthera, Hymenolepis and Phymaspermum .  相似文献   

13.
DICK, M. VV., 1986. A new family and a new genus for two taxa previously assigned to Apodachlyella completa (J. E. Humphrey) H. Indoh (Peronosporomycetidae: Leptomitales) . At present two distinct taxa are referrable to Apodachlyella completa. New genus and species names (I'lerogone helodes M. W. Dick genus & sp. nov.) are necessary for the taxon reported from the British Isles. Confirmation of the unique wall membranes in the antheridia and oogonia is used to justify the placement of A. completa in a new, monotypic family of the Leptomitales (Apodachlyellaceae M. W. Dick fam. nova). Plerogone is placed provisionally in the Leptomitaceae.  相似文献   

14.
Species discrimination within the gigartinalean red algal genus Hypnea has been controversial. To help resolve the controversy and explore phylogeny within the genus, we determined rbcL sequences from 30 specimens of 23 species within the genus, cox1 from 22 specimens of 10 species, and psaA from 16 species. We describe H. caespitosa as a new species characterized by a relatively slender main axis; a pulvinate growth habit with entangled, anastomosing, and subulate uppermost branches; and unilaterally borne tetrasporangial sori. The new species occurs in the warm waters of Malaysia, the Philippines, and Singapore. The phylogenetic trees of rbcL, psaA, and cox1 sequences showed a distant relationship of H. caespitosa to H. pannosa J. Agardh from Baja California and the marked differentiation from other similar species. The rbcL + psaA tree supported monophyly of the genus with high bootstrap values and posterior probabilities. The analysis revealed three clades within the genus, corresponding to three sections, namely, Virgatae, Spinuligerae, and Pulvinatae first recognized by J. G. Agardh. Exceptions were H. japonica T. Tanaka in Pulvinatae and H. spinella (C. Agardh) Kütz. in Spinuligerae.  相似文献   

15.
Haplodontium zangii X.R.Wang &; J.C.Zhao, a new moss species from Xizang, China, is described and illustrated. Previously, specimens of H. zangii have been identified as Mielichhoferia himalayana Mitt. However, H. zangii is distinctly different from M. himalayana in having excurrent costae with short awns (vs long denticulate awns), short-pyriform capsules, 0.8–1?mm (vs long-pyriform capsules, 2.5–3?mm), and densely papillose exostome teeth (vs smooth or vertically striped exostome teeth). Haplodontium zangii is similar to H. macrocarpum (Hook.) J.R.Spence, which was traditionally placed in Mielichhoferia Nees &; Hornsch. as M. macrocarpa (Hook.) Bruch &; Schimp. The main differences between H. zangii and H. macrocarpum are in the morphology of the leaves, capsules, guide cells, and stomata. Mielichhoferia himalayana and another Chinese species of Mielichhoferia, M. sinensis Dix., are also transferred to Haplodontium Hampe, a new genus in the bryoflora of China, as H. himalayanum (Mitt.) X.R.Wang &; J.C.Zhao and H. sinensis (Dix.) X.R.Wang &; J.C.Zhao. A morphological comparison and a key to the three species of Haplodontium in China as well as to H. macrocarpum, a species that is likely to be found in China, are provided.  相似文献   

16.
Didymodon liae J. Kou, X.‐M. Shao & C. Feng sp. nov., is described and illustrated from Dagzê County in south central Tibet, China. The new species is most similar to Didymodon australasiae (Hook. & Grev.) R. H. Zander, but differs in plants growing loosely in a thin turf, stems without hyalodermis and sclerodermis, margins recurved from just above the base nearly to the apex, laminal cells strongly bulging, mammillose, covered with simple or forked papillae, and costa with a layer of ventral substereids. The new species is contrasted with other similar species of the genus. Information on its distribution and ecology is also provided.  相似文献   

17.
The present paper is an attempt to propose a preliminary taxomomic treatment of the genus Hippolytia Poljak. and to analyse the geographical distribution of its composite elements. This small genus with 17 species is divided into 2 sections, namely, section Anthodesma Shih and section Hippolytia. Anthodesma is a small section with 3 species and is characterized by fascicled corymbs, campanulate and nitid involucres, rigidly herbaceous phyllaries, and undershrubs, while Hippolytia consisting of 14 species is characterized by corymbose inflorescence or glomerules or compund heads, cuneate and unpolished involucres, herbaceous phyllaries with pitch black margines. There are 12 species of Hippolytia in China, of which 3 are proposed as new in the present paper. Regarding the distribution pattern of Hippolytia, it is noteworthy to note that its range of distribution forms a more or less U-shape as shown in map 2. It may be seen that Hippolytia distributes in Central Asia-Sino-Himalaya-Median Asia. Section Anthodesma Shih occurs in central Asia, while section Hippolytia in the whole Himalayan region and northern Meridional Ranges and Median Asia. There seems to be no center of species concentration within the total range of Hippolytia, whose species are localized in distribution, for example, H. desmantha Shih is known only from Qinghai provence (Yu-Shu-Hsien), H. alashanensis (Ling) Shih is restricted to Ninghsia and central part of Kansu provence. It is interesting to note that H. yunnanensis (J. F. Jeffrey) Shih and H. longifolia (Wall.) Shih are referred to as vicarious species. The localization of the species distribution and the obvious discontinuity of morphological characters between species indicate a remarkable geographical influence on the species formation of Hippolytia. Hippolytia is an alpine genus of temperate zone of Asia, in which 64 per cent of species occurs at high elevations of above 3300m. altitude, 30 per cent of species are distributed in middle elevations of above 2200m. altitude. The life forms are microundershrubs, erect perennial herbs, glomerule stemless herbs or stemless herbs. It is very possible that its geographical origin and development may be linked up with occurance of desert steppe, especially of alpine meadow vegetations in the northern temperate zone of Asia. With regard to the geographical elements to which each species of Hippolytia belongs, it seems to indicate that H. trifida (Turcz.) Poljak., H. alashanensis (Ling) Shih and H. desmantha Shih belong to the geographical elements of central Asia, while H. yunnanensis (J. F. Jeffrey) Shih, H. glomerata Shih, H. tomentosa (DC.) Tzvel., H. senecionis (Bess.) Poljak. H. longifolia (Wall.) Shih, H. kennedayi (Dunn) Ling, H. syncalathiformis Shih, H. gossypina (Hook. f. et Thoms.) Shih and H. nana (C. B. Clarke) Shih to Himalayan elements, and H. darvasica (C. Winkl.) Poljak., H. megacephala (Rupr.) Poljak,, H. herderi (Rgl. et Schmalh.) Poljak. to Median Asia, H. delavayi (W. W. Smith) Shih to North-West-Yunna.  相似文献   

18.
采用经典分类学研究方法,对河北师范大学植物标本馆(HBNU)等国内多个标本馆保存的中国丝瓜藓属直蒴组(Pohlia Hedw.section Cacodon Lindb.ex Broth.)及其近缘类群植物标本共计130余号进行了分类学分析鉴定,并对所确定的中国产直蒴组物种的芽胞大小、形状及叶原基数量和长度等形态学特征进行比较分析,以期为中国丝瓜藓属直蒴组的分类学研究提供理论依据。结果表明:(1)经鉴定中国丝瓜藓属直蒴组植物共有8种——夭命丝瓜藓[Pohlia annotina(Hedw.)Lindb.]、糙枝丝瓜藓[P.camptotrachela(Ren.Card.)Broth.]、林地丝瓜藓[P.drummondii(Müll.Hal.)Andr.]、疣齿丝瓜藓[P.flexuosa Harv.]、纤毛丝瓜藓[P.hisae T.J.Kop.et J.X.Luo]、异芽丝瓜藓[P.leucostoma(BoschSande Lac.)M.Fleisch.]、念珠丝瓜藓[P.lutescens(Limpr.)H.Lindb.]和卵蒴丝瓜藓[P.proligera(Kindb.ex Breidl.)Lindb.ex Arnell]。(2)中国丝瓜藓属直蒴组植物的重要鉴别特征是在假根或叶腋处生有芽胞,而且芽胞形状以及叶原基形状和数量在直蒴组中存在差异,如念珠丝瓜藓具有假根生芽胞,而疣齿丝瓜藓具有两型芽胞。(3)对所鉴定的中国丝瓜藓属直蒴组8种植物的识别特征、生境及其与相近种的关系进行了详细描述,并绘制了形态特征墨线图。  相似文献   

19.
Critical examination of the literature and specimens of the three described species of Euthora indicates that the acceptance of the northern species E. cristata (C. Ag.) J. Ag. and E. fruticulosa (Rupr.) J. Ag. has been based on lack of familiarity with the degree of variation normal within one species, and these two species should be united. The carpogonial branch system of this combined species is typical of that found in the genus Callophyllis within which it should therefore be included as Callophyllis cristata (C. Ag.) Kütz. The taxonomic position of the only other species of Euthora, E. tristanensis Baardseth, cannot be determined until information on the carpogonial structure is available.  相似文献   

20.
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