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Douglas C. Daly 《Brittonia》1992,44(3):280-299
Revision ofProtium in eastern Amazonia and the Guianas yielded one new section, three new species, three new subspecies, and five new combinations in the genus. SectionSarcoprotium Daly is distinguished principally by the cucullate petals with clawed bases and usually with a dorsal thickening produced vertically as an appendage; staminate inflorescences with a few 3-merous flowers; thecae of the anthers completely separated by the connective and the dehiscence latero-introrse; and fruit ellipsoid when only one pyrene develops.  相似文献   

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The ultrastructure ofCucullosporella mangrovei ascospores is described. Mature ascospores possess two wall layers, an outer electron-dense episporium and an innermost tripartite mesosporium. Episporial elaborations form electrondense spore wall ornamentations from which extend fibrils that may constitute a highly hydrated exosporium which was not visualised at either the scanning electron microscope or light microscope level. Ascospores possess a hamate appendage at each pole which unfolds in seawater to form a long thread. Ultrastructurally the polar appendage comprises folded fibro-granular electron-dense material and fine fibrils. The fibrils form a matrix around and within the fibro-granular appendage and around the entire unreleased ascospore. These fibrils have not been observed associated with the ascospore appendages in other species of the Halosphaeriales and are a discrete and new appendage component. The fibro-granular appendage and fibrils are bounded by the outer delimiting membrane which is absent around released ascospores. The nature of the spore appendage is compared with that of other marine and freshwater ascomycetes and the taxonomic assignment of the species is discussed.  相似文献   

4.
Data on the reproductive biology of the genus Hippolyte are available from studies of Hippolyte inermis. These findings support the idea that these species are protandric hermaphrodites, exhibiting sex reversal. However, recent studies of this and other species, such as Hippolyte obliquimanus and Hippolyte williamsi, have not reported sex reversal and suggest a gonochoric condition. In the present study, histological analyses were conducted of the ovaries, testes, oviducts, vasa deferentia and the development of the male appendage. The results of this study show that the Hippolyte niezabitowskii population from southern Spain should also be viewed as a gonochoric species. The study found no evidence of sex reversals. These conclusions are also supported by information on the structure of the population and by the results of studies of the male appendage. The population structure involves different size distributions of males and of females. Size classes 2-14 exhibit substantial overlap. No evidence of sex reversal was obtained from the study of the male appendage.  相似文献   

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Tod F. Stuessy 《Brittonia》1969,21(4):314-321
The type species ofUnxia, U. camphorata, long considered as a species ofMelampodium, andPolymnia suffruticosa are regarded as congeneric, andUnxia L. f., which is closely related toPolymnia in the Melampodiinae, is re-established. A discussion of generic relationships is followed by a taxonomic treatment ofUnxia.  相似文献   

6.
A leaf spotting disease of an ornamental variety of Ophiopogon japonicus was discovered at several locations in northern Thailand. In all cases a species of Phyllosticta was associated with the lesions. Phyllosticta ophiopogonis sp. nov. is distinguished from Phyllosticta species from Liliaceae in conidia size, mucilaginous sheath and appendage thus the species is introduced as new in this paper. The new species which causes unsightly lesions on this ornamental plant is described, illustrated and compared with other similar Phyllosticta species.  相似文献   

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Three new species of the sciaenid genusAtrobucca are described:A. kyushini from off Borneo, differs from all known congeners in having no swimbladder appendages enveloplng the bladder, no forward directed branches from the ventral limbs of the appendages, a long tube-like last appendage parallel to the bladder wall and a pale mouth lining;A. brevis from off northern Australia and Papua New Guinea, is distinguished by its short pectoral fin (less than 23% SL) and pleural rib on the 11th vertebra;A. adusta from Papua New Guinea, is distinctive in having a low dorsal soft ray number (23–24) and long caudal peduncle (27–30% SL).Atrobucca Chu, Lo et Wu is redefined to accommodate the new species: the genus is principally characterized by the swimbladder appendages divided into developed dorsal and ventral limbs, and the only slightly curved sulcus tail of the sagitta. A key and diagnoses are provided for all known species ofAtrobucca.  相似文献   

9.
The genus Cordia (Boraginaceae) is made up of a great many species widely distributed in tropical and subtropical regions of the world. The leaves ofCordia myxa, as also those of many other species of the same genus, have been utilized in the traditional medicine of many countries for the treatment of a variety of diseases. Observed by light microscope and by scanning electron microscope the histological characteristics of the leaf ofCordia francisci, C. martinicensis, C. serratifolia andC. ulmifolia, species grown in Sicily, compared also with those of the leaves ofC. myxa originating from Africa, are described in detail. It has been possible to reveal some morphological elements that allow leaf identification and the differentiation of the drugs examined.  相似文献   

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TheCalyptridium umbellatum complex (Portulacaceae), which has been treated as including from one to nine species, is shown to comprise three morphologically distinctive species. Two of these are common, wide-ranging, montane perennial herbs—C. umbellatum, which occurs over a large part of western North America, andC. monospermum, which largely replacesC. umbellatum in cismontane California. The third member of the complex is the rare or possibly extinctC. pulchellum. The perennial members of this complex are accorded the status of a separate genus,Spraguea, by most authors, but a comparative study of the morphology and karyology of all species ofCalyptridium shows this separation to be unwarranted. Chromosome numbers ofn = 22, obtained from eight populations ofC. umbellatum and six ofC. monospermum, constitute the first reported counts for these species. Hybridization studies involvingC. umbellatum andC. monospermum indicate that they are isolated by an incomplete noncrossability barrier.  相似文献   

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New species ofBletia from Mexico are described and illustrated:B. concolor, B. similis, andB. urbana. The identity ofB. campanulata Llave & Lex. is discussed, andB. reflexa Lindl. is considered to be a distinct species. Several South American epithets are treated as synonyms ofB. campanulata. A key to the recognized species ofBletia is given.  相似文献   

14.
Recent generic realignments of the perennial grasses of the tribe Triticeae necessitate some new name combinations for North American species. Three new species combinations and three new subspecies combinations are made to accommodate six long-anthered and usually cross-pollinating species ofAgropyron sensu A. S. Hitchcock in the genusElytrigia sensu N. N. Tzvelev. Three new species combinations are made to accommodate three long-anthered and usually cross-pollinating species ofElymus sensu A. S. Hitchcock in the genusLeymus sensu N. N. Tzvelev. A complete listing is given of the North American species and subspecies ofElytrigia andLeymus as I perceive them.  相似文献   

15.
Micromorphological characters of 113 species of the South American genus Lessingianthus H.Rob. (Vernonieae, Asteraceae) were analyzed to evaluate their reliability as taxonomic markers. The corolla pubescence was studied in detail for the first time in the genus. Glandular and non-glandular trichomes were studied and described. The trichome types allow differentiation among related species, but do not reflect the relationships among species groups. On the other hand, the basal stylar node only occurs in a distinctive group of species within the genus. The apical appendage of the anthers is non-glandular in all species of the genus. Several character states analyzed in Lessingianthus are often widespread in other related genera of Vernonieae. Therefore, Lessingianthus can be circumscribed only by a combination of micro- and macromorphological features.  相似文献   

16.
Acastid trilobites from Ludlow strata on Gotland include three stratigraphically non-overlapping species ofAcastella Reed:Acastella madidipes n. sp. (Hemse Marl and Eke Beds),A. breviceps (Angelin 1851) (Burgsvik Beds), andA. amatrix n. sp. (Hamra Beds, and probably Burgsvik Beds). Type and other material ofA. breviceps (Angelin) from the Klinta Formation, Scania, is revised. Meraspid and early holaspid material ofAcastella is described. Some characters supportAcaste and allied taxa of mostly Wenlock age as a monophyletic subfamily Acastinae.Acastella as widely recognized is a grade with Devonian species more closely related to Asteropyginae than to the Ludlow type species. Baltic Ludlow-P?00ED;dolí species previously placed inScotiella Delo form a distinct group,Ewacaste n. gen., that includes a species from the uppermost Eke Beds on Gotland.  相似文献   

17.
Field experiments were conducted to study the influence of cabbage monoculture and mixed cropping on the parasitism of diamondback moth,Plutella xylostella (L.), a destructive pest of all crucifers, by 2 larval parasites,Diadegma semiclausum Hellén andCotesia plutellae Kurdjumov. There was no significant difference in parasitism by either species whether cabbage was planted in insecticide-free monoculture or in mixed cropping with 8 noncrucifers which were sprayed twice a week with chemical insecticides mevinphos, methamidophos and permethrin. Population ofP. xylostella increased as the cabbage plants grew older. Parasitism byC. plutellae was higher soon after cabbage transplanting but decreased as the plants grew older. Parasitism byD. semiclausum was very low soon after cabbage planting but increased as the plants grew older. A significant negative correlation was found betwen parasitism byC. plutellae andD. semiclausum. In a caged field study where only one parasite species was used in an individual cage, parasitism ofP. xylostella by both species decreased as theP. xylostella population increased. This is believed to be due to the absence of competition between the two parasites inside the cage. There was no relationship between host-plant age and parasitism ofP. xylostella larvae by either parasite species.  相似文献   

18.
A recent study of Southeastern species ofStachys points out a problem involving the identity ofS. nuttallii Shuttlew. ex Bentham. Type material ofS. nuttallii is clearly representative of what is commonly known asS. riddellii House.S. riddellii of current authors must now be calledS. nuttallii, S. riddellii becoming a taxonomic synonym. However, no valid names have been uncovered in the literature that can be correctly applied to the species, primarily from the Blue Ridge Mountains, previously known to most botanists as “S. nuttallii.” These plants are described as a new species,Stachys eplingii.  相似文献   

19.
Xenomeris saccifolii is described from leaves ofSaccifolium bandeirae (Gentianales, Saccifoliaceae);Gibbera sphyrospermi is described from fruit ofSphyrospermum cordifolium (Ericales, Ericaceae). The anamorph ofG. sphyrospermi is presumed to be a species ofStigmina. The concept ofStigmina is expanded to include species with unicellular conidia produced on branched conidiophores.  相似文献   

20.
Six species of the orchid speciesLepanthes are described as new. A seventh species,L. sanguined, previously known only from Jamaica, is reported from Puerto Rico. The current misspelling ofL. selenitepala, the only species of the genus previously reported from Puerto Rico, is corrected. A key to the eight Puerto Rican species ofLepanthes is presented, and the value of several interesting taxonomic characters is discussed. The possibility of apogamy in this genus is raised, and detailed biosystematic investigations are indicated as necessary for a complete understanding of the group.  相似文献   

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