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1.
A new naturally occurring chalcone glycoside, 2′,-dihydroxy-4-methoxy-4′-O-β-d-glucosyl chalcone, and other chalcones, aurones, flavonols, and anthocyanins are reported from Megalodonta (Bidens) beckii. The plan is an amphibious aquatic with heterophyllous leaves, but the presence of certain flavonoids is correlated with vegetative versus floral tissues rather than vegetative leaf form. The implications of flavonoid chemistry with respect to the relationship of M. beckii to several sections of Bidens are discussed.  相似文献   

2.
The parasitoids ofAonidiella aurantii (Maskell),Lepidosaphes beckii (Newman) andParlatoria pergandii Comstock were studied in a Navel orange grove in Valencia, Spain during three years. Four species ofAphytis were identified on yellow sticky traps,Aphytis chrysomphali (Mercet),Aphytis melinus Debach,Aphytis lepidosaphes Compere andAphytis hispanicus (Mercet). No consistent annual pattern was observed in the flight of adults.A. melinus, introduced some years earlier in the grove, was found in very low numbers and showed no signs of increasing and displacingA. chrysomphali as a parasitoid ofA. aurantii. On female scales of the three species sampled at regular intervals from leaves, twigs and fruit, the mean annual rate of active parasitism was similar and ranged from 3.5% to 8%.P. pergandii males were not parasitized, inL. beckii parasitism was usually much lower in male than in female scales, and inA. aurantii it was higher in the males. Scales of the three species were less parasitized on twigs than on leaves, and so wereL. beckii on fruit. The annual trend of parasitism byAphytis on scales fluctuated without a definite pattern. Parasitism byEncarsia inquirenda (Silvestri), an endoparasitoid ofP. pergandii, was more stable throughout the year and increased steadily from year to year.  相似文献   

3.
描述了竹亚科思劳竹属一新种——万石山思劳竹(Schizostachyum wanshishanensis S.H.Chen,K.F.Huang et H.Z.Guo)。该种与思劳竹(S.pseudolima McClure)近缘,但本种箨片较平直,且短,长不及箨鞘之1/2,叶表无毛,叶背具柔毛,易于区别;本种也与沙罗单竹(S.funghomii McClure)近缘,但本种秆梢端细长下垂,叶鞘具有白色短刺毛,易于区别。  相似文献   

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5.
A new genus and species of sea pen or virgulariid pennatulacean from the Gulf of Guinea in the tropical eastern Atlantic is described, and a key to the genera of the Virgulariidae is included. The new genus and species described here adds to the previously described five other genera of the family. It is distinguished by unique sclerite and polyp leaf characters from the superficially-similar genus Virgularia, which lacks conspicuous sclerites in the polyp leaves and coenenchyme (other than minute oval bodies that are generally <0.01 mm in length).  相似文献   

6.
A long rachis of Bottyopteris aff. hirsuta bearing twin opposite lateral shoots is described from a coal ball of Westphalian age collected in Lancashire. The simultaneous emission, in the middle region of a frond, of two short axes each bearing a large number of poorly developed leaves is a feature hitherto unrecorded for the genus. The specimen suggests that this Paleozoic fern consisted of long fronds whose branching pattern showed a certain capacity for morphological variation; it provides yet another example of the surprisingly limited development of shoots borne on Botryopteris fronds.  相似文献   

7.
Oberholzeria etendekaensis, a succulent biennial or short-lived perennial shrublet is described as a new species, and a new monotypic genus. Discovered in 2012, it is a rare species known only from a single locality in the Kaokoveld Centre of Plant Endemism, north-western Namibia. Phylogenetic analyses of molecular sequence data from the plastid matK gene resolves Oberholzeria as the sister group to the Genisteae clade while data from the nuclear rDNA ITS region showed that it is sister to a clade comprising both the Crotalarieae and Genisteae clades. Morphological characters diagnostic of the new genus include: 1) succulent stems with woody remains; 2) pinnately trifoliolate, fleshy leaves; 3) monadelphous stamens in a sheath that is fused above; 4) dimorphic anthers with five long, basifixed anthers alternating with five short, dorsifixed anthers, and 5) pendent, membranous, one-seeded, laterally flattened, slightly inflated but indehiscent fruits.  相似文献   

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10.
A new genus and species,Dedeckera eurekensis, are described from the Last Chance Mountains, Inyo Co., California, from an area just south of the Eureka Valley sand dunes. A member of Polygonaceae, it is most closely related toEriogonum, differing from that genus in lacking a tubular involucre, and fromStenogonum, Hollisteria, Nemacaulis, andGilmania in being a shrubby perennial. It differs from all other members of the subfamily Eriogonoideae in having (1) a head of subsessile or sessile flowers borne on a slender peduncle and subtended by 2 to 5 foliaceous bracts, and (2) a single short-pedicellate axillary flower at the base of each peduncle. The numerous yellow-flowered heads are arranged in open cymose inflorescences that terminate short annually produced branches with alternately arranged exstipulate foliage leaves.Eriogonum flexum is transferred to the genusStenogonum. A key to the genera of subfamily Eriogonoideae is included.  相似文献   

11.
《Mycoscience》2014,55(2):124-126
A new species of the monotypic genus Pseudohypocrea is described based on a collection from Tai Po Kau, Hong Kong, China. The fungus is characterized by globose to subglobose perithecia entirely immersed in a pulvinate reddish-brown stroma, cylindrical asci with smooth-walled and lemon-shaped part-ascospores, and occurring on dead leaves. Morphological features of the new species are described and compared with the only known species of the genus.poi  相似文献   

12.
V. A. Funk 《Brittonia》1997,49(1):110-117
A new genus is described based on a species formerly found in Werneria s.1. It is named after a collector, Miss Winifred M. A. Brooke. The new genus, Misbrookea, is confined to dry, high-elevation areas in Peru and northern Bolivia. It is distinguished by its unusual, long, multicellular hairs that cover the leaves and involucre of the plant, the style apices with long, multicellular hairs and apparent vascular traces, and the pale or silvery gray-green color of the leaves and involucre.  相似文献   

13.
A new genus and species of fossil Glaphyridae, Cretohypna cristata gen. et sp. n., is described and illustrated from the Mesozoic Yixian Formation. This new genus is characterized by the large body; large and strong mandibles; short labrum; elytra without longitudinal carina; and male meso- and possible metatibia apically modified. A list of described fossil glaphyrids of the world is provided. This significant finding broadens the known diversity of Glaphyridae in the Mesozoic China.  相似文献   

14.
王文采 《植物研究》2013,33(6):641-643
描述了自河北省发现的毛茛科乌头属一新种,迁西乌头。此新种在叶和花的形状方面与乌头像似,但其块根二叉状分枝,茎低矮,之字形弯曲,无毛,叶较小,无毛,花单朵顶生,花梗、萼片外面和心片均无毛,而与乌头相区别。  相似文献   

15.
A new cicada genus and species, Minilomia triquetra, gen. and sp. nov., is described from Borneo. The new genus Minilomia is closely allied to Platylomia Stål and is placed in the subtribe Dundubiina of the tribe Cicadini. Another new cicada species, Pomponia brevicaudata, sp. nov. (subtribe Psithyristriina), is described from Java and Sumatra. The new species belongs to the Pomponia linearis species group and the P. linearis species complex but is distinguished from its congeners by the unusually short male abdomen.  相似文献   

16.
A new species of Ephedranthus from the Brazilian Atlantic Forest is described and illustrated, and a preliminary key to the species of Ephedranthus is presented. Ephedranthus dimerus is the only species of the genus from the Atlantic Forest region and the first species of the genus with dimerous flowers. It is similar to E. guianensis in having narrowly obovate to elliptic leaves with similar dimensions and a cuneate to acute base. Nevertheless, the two species can be distinguished from each other by the number of monocarps per fruit and by the length of the stipe.  相似文献   

17.
《Journal of bryology》2013,35(4):234-239
Abstract

A new genus, Acaulonopsis (Pottiaceae, Bryophyta), including two new species, A. fynbosensis and A. eureka, is described from the Western Cape Province of South Africa. Together with the similarly much reduced pottiaceous genus Acaulon, Acaulonopsis is unique in the family with a very short seta and spherical capsule, which lacks the apiculus found in other genera. The new genus is also distinguished by short plant stature, and a total of about five ovate leaves that clasp closely the capsules in nearly spherical leaf bases. Continuing bryological study of the fynbos region has recently resulted in a number of startling discoveries of bryophytes new to science and distinct at the genus level. A new combination is made for the South African endemic genus Vrolijkheidia (Pottiaceae) with discussion of its dimorphic habitus.  相似文献   

18.
A new approach to the formal classification of arthropod margin feeding plant damage is proposed. Several types of margin feeding traces on the leaves of Pityophyllum sp. and Ginkgoites sp. from the Upper Jurassic-Lower Cretaceous Chernovskie Kopi locality, Transbaikalia, are described as five new species in the genus Pinovulnus gen. nov.  相似文献   

19.
Sobralia vallecaucana, section Abbreviatae from Valle del Cauca, Colombia, is described and illustrated on the basis of morphological and molecular study. The analyses of the ITS and matK reveal close relationship between the new species and Sobralia klotzscheana. However, S. vallecaucana can be easily distinguished by its large leaves compared to its very short stem, leaves and leaves’ sheaths strongly hispid underside and lip with two basal ridges and without thickening along its central nerves.  相似文献   

20.
Odontocarya monandra Barneby, resembling O. deminuta in glabrous staminate panicle, 3-merous corolla and solitary stamen, but notably different in shape and venation of leaves and larger staminate flowers, is described from Prov. Maynas, northeastern Peru; and O. septemfida Barneby, the only known member of the genus with lobed leaves, from Edo. Falcón, Venezuela.  相似文献   

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