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1.
2.
Sixteen species of Copepoda were recorded in this first detailed study of Costa Rican zooplankton. Two of these species are halophile. Notes are given on some of the species and their distribution. One new species found will be described elsewhere. The Costa Rican fauna resembles in composition the fauna of other Central American and Caribbean regions. Relatively few species were recorded. This is partly due to a low intensity of sampling but also to the paucity of lentic habitats. The occurrence of two circumtropical species of Mesocyclops is interesting.
Résumé 16 espèces de Copépodes ont été inventoriées au cours d'une première étude détaillée du zooplankton dulcaquicole de Costa Rica. Deux des espèces trouvées sont halophiles. Des remarques sont faites a propos de quelques espèces et de leur répartition. Une nouvelle espèce est nouvelle — elle sera décrite par ailleurs. La fauna de Costa Rica ressemble par sa composition à celle des autres pays d'Amérique centrale et des îles caraibes. Relativement peu d'espèces sont notées. La faible intensité de l'échantillonnage mais aussi la pauvreté en habitats limniques en sont responsables. La présence de deux espèces circumtropicales de Mesocyclops est intéressante.
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3.
The rough periwinkle Littorina saxatilis is considered, in current literature, to consist of various sympatric "subspecies" and "varieties". These, it has been suggested, are incipient species and are evidence for sympatric speciation.
This paper shows that in Wales the "saxatilis" aggregate consists of four separate, fully sympatric species: L. rudis, patula, nigrolineata and neglecta . Differences between these species include proportions, sculpture and size of the shell, range of colour patterns, the anatomy of the genitalia, and isozyme patterns. The possible evidence for incipient species is discussed and rejected.
The diversity of penis form amongst the British winkles is remarkable, and it is suggested that in these sympatric species the structure of the penis could be of importance in species recognition.
The four species occupy different zones on the shore and three certainly differ also in their methods of reproduction: L. rudis is ovoviviparous and contains embryos throughout the year, patula is ovoviviparous but contains embryos only in winter, nigrolineata is oviparous. The reproduction and dispersal methods of all British winkles are reviewed. The evidence available supports the view that non-planktonic dispersal is an adaptation which, in species whose shell colour varies considerably from one locality to another, enables each population to become adapted to its local environmental conditions. Ovoviviparity occurs in high-shore non-planktonic species, and may be an adaptation to avoid the dangers of egg desiccation. Planktonic dispersal is found in species whose shell colour does not vary as much as in non-planktonic ones. In these species, it is argued that a common planktonic pool enables a rapid re-colonization in the case of local decrease in population numbers, and also the rapid dispersal of successful mutations.  相似文献   

4.
Lectotypification of Crataegus crus-galli permits the common ten-stamened entity of the northern United States and adjacent Canada to retain its name. The correct name for the related 20-stamen form, usually called C. fontanesiana, is C. tenax. Crataegus persimilis, lectotypified here, is shown to occur in Ontario as well as New York, having been previously misidentified as C. ?bushii and C. prunifolia in Ontario. A horticultural taxon usually (but improperly) called C. prunifolia is provided with a new cultivar name.  相似文献   

5.
A discussion on the generic delimitation of the orchid genera Brevilongium and Otoglossum is presented. Additional notes on Ecuadorella are provided. A comparison of the morphological characters of the genera is presented together with a key to their identification. Moreover, two new species of Brevilongium and four species of Otoglossum are described and illustrated. The taxonomic affinities of the new taxa are briefly discussed. Keys to the identification of Brevilongium and the Colombian species of Otoglossum are provided.  相似文献   

6.
Ju YM  Rogers JD  Hsieh HM 《Mycologia》2004,96(1):154-161
These new species of Hypoxylon are described: H. elevatidiscus, H. squamulosum, H. subalbum and H. vinosopulvinatum. A referenced list of all Hypoxylon species known to us described since 1996 is given and a key presented. Names associated with Hypoxylon that were not given in the Ju and Rogers monograph are annotated and diagnostic corrections of taxa discussed in that monograph are given.  相似文献   

7.
Ten new genera, five new subgenera, and five new species are described in the family Dictyopharidae. Three generic names are synonymized. A new name is proposed for the generic homonym. Dictyophara kazeruna Dlabola is transferred to the genus Callodictya Melichar. The genus Sinodictya Matsumura, with the type species Sinodictya tukana Matsumura, is redescribed. A new key to the tribes of the subfamily Dictyopharinae is given. The composition and characters of the tribes Taosini and Lappidini are revised. All the genera of the subfamily Dictyopharinae are listed according to their tribal position. New records are given for some interesting species.  相似文献   

8.
The status of subfamilies and genera within Chondracanthidae Milne Edwards, 1840 has recently been revised. Forty four genera are currently recognised as valid for the Chondracanthidae and a comprehensive catalogue to the valid genera and species of the family is presented here. In addition, numerous supplementary observations are presented on existing taxa for which incomplete or inadequate data were previously available.  相似文献   

9.
根据对中国蛇根草属Ophiorrhiza植物标本的研究和野外调查,将琼崖蛇根草O.aureolina f.qiongyaensis Lo和溪畔蛇根草O.humilis Tseng归并入短小蛇根草O.pumila Champ.ex Benth.,将海南蛇根草O.hainanensis Tseng归并入垂花蛇根草O.nutans C.B.Clarke,将广西蛇根草O.kwangsiensis Merr.exLi和变黑蛇根草O.nigricans Lo归并入日本蛇根草O.japonica Bl.,将龙州蛇根草O.longzhouensis Lo和圆锥蛇根草O.paniculiformis Lo归并入广州蛇根草O.cantoniensis Hance。  相似文献   

10.
The phylogenetic position of the African and Malagasy species of Pimpinella is assessed using nrDNA ITS sequence data and a representative sampling of the genus, including 16 species from Africa and Madagascar and 26 species from Eurasia. The results of maximum parsimony and Bayesian analyses of these data show that the African and Malagasy species ally with their Eurasian counterparts in Pimpinelleae. The genus Pimpinella is rendered paraphyletic by the inclusion of African Cryptotaenia and the small African and Malagasy endemic genera Frommia and Phellolophium. Within a paraphyletic Pimpinella, three major clades are recovered, with the African species occupying two of these clades. The current sectional classification of the genus, based predominantly on fruit vestiture, is largely artificial. Chromosome base number, however, was found to be consistent with the groupings recovered in the molecular analyses. Those African and Malagasy Pimpinella species with a chromosome base number of x = 11 and largely glabrous petals and fruits, form the earliest diverging clade together with Frommia, which also has a base count of n = 11 and glabrous petals and fruits. The remaining African species ally with several Eurasian species of Pimpinella and share a chromosome base number of x = 9 and usually hairy petals and fruits.  相似文献   

11.
Ten species are recognized in the genus Hypocenomyce. Their morphology, anatomy, chemistry, and ecology are discussed, a key is provided, and their distribution in Norway and Sweden is mapped. Hypocenomyce australis Timdal and H. foveata Timdal are described as new, and the combinations H. castaneocinerea (Räsänen) Timdal and H. praestabilis (Nyl.) Timdal are proposed. The genus can be divided into four species groups on the basis of apothecial and conidial characters, type of pigment in the epithecium and pyenidial wall, and chemical properties of the thallus. The delimitation of the genus in relation to Lecidea s. lat. is in need of further elucidation.  相似文献   

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14.
This study constitutes the first evolutionary investigation of the snake family Psammophiidae--the most widespread, most clearly defined, yet perhaps the taxonomically most problematic of Africa's family-level snake lineages. Little is known of psammophiid evolutionary relationships, and the type genus Psammophis is one of the largest and taxonomically most complex of the African snake genera. Our aims were to reconstruct psammophiid phylogenetic relationships and to improve characterisation of species boundaries in problematic Psammophis species complexes. We used approximately 2500 bases of DNA sequence from the mitochondrial and nuclear genomes, and 114 terminals covering all psammophiid genera and incorporating approximately 75% of recognised species and subspecies. Phylogenetic reconstructions were conducted primarily in a Bayesian framework and we used the Wiens/Penkrot protocol to aid species delimitation. Rhamphiophis is diphyletic, with Rhamphiophis acutus emerging sister to Psammophylax. Consequently we transfer the three subspecies of Rhamphiophis acutus to the genus Psammophylax. The monotypic genus Dipsina is sister to Psammophis. The two species of Dromophis occupy divergent positions deeply nested within Psammophis, and we therefore relegate Dromophis to the synonymy of Psammophis. Our results allow division of the taxonomically problematic Psammophis 'sibilans' species complex into two monophyletic entities, provisionally named the 'phillipsii' and 'subtaeniatus' complexes. Within these two clades we found support for the status of many existing species, but not for a distinction between P.p. phillipsii and P. mossambicus. Additionally, P. cf. phillipsii occidentalis deserves species status as the sister taxon of P. brevirostris.  相似文献   

15.
The Australian snakes that have been included in Aspidomorphus differ markedly from that genus, particularly in hemipenial morphology and in the absence of a muscular slip from the quadrate bone to the venom gland; the genus Aspidomorphus is therefore restricted to the New Guniea species. Aspidomorphus (as here restricted) is closely related to Demansia (in the restricted sense of Worrell, essentially D. psammophis, D. torquata , and D. olivacea ), but the Australian species generally referred to Aspidomorphus seem to be related to Glyphodon . The genera Aspidomorphus, Demansia, Rhinhoplocephalus and Drepanodontis form a natural group. Aspidomorphus contains three species, each identifiable by hemipenial features as well as by details of colouration: A. muelleri (= A. mülleri mülleri and A. m. interruptus of Brongersma's revision); A. lineaticollis (= A. mülleri lineaticollis and A. m. lineatus of Brongersma); and A. schlegeli. The last species differs from the others in the form of the maxillary bone and the anterior mandibular dentition; it seems to be confined to northwestern New Guinea and adjacent islands, since specimens from the eastern end of New Guinea that had been referred to schlegeli are actually A. lineaticollis. In all three species some geographical variation can be demonstrated, at least in ventral count, but it is not considered necessary to use trinomials to indicate that geographical variation exists. Pseudonaja textilis is recorded from New Guinea for the first time. (McDowell.)
Examination reveals Demansia ornaticeps is properly referred to Demansia. (Cogger.)  相似文献   

16.
Previous systematic treatments of Menonvillea recognized a group of six morphologically related species, the ‘M. scapigera group,' distinguished by having pinnately lobed leaves and united filaments of median staminal pairs. The number of recognized species ranged from six to two, one with three subspecies. In order to clarify the taxonomy of this group, multivariate and univariate analyses of qualitative and quantitative characters from herbarium specimens were performed. Additionally, to test the morphological results, the phylogenetic relationships and degree of exclusive ancestry were studied using ITS sequences and the genealogical sorting index. Our results support the recognition of three species (M. famatinensis, M. hirsuta, M. scapigera) delimited by a unique combination of qualitative characters. Quantitative characters support the division of the latter species into two subspecies: scapigera and longipes. The molecular data are congruent with the morphology and support the inclusion of M. hookeri within M. scapigera. A key to taxa of the M. scapigera group is presented.  相似文献   

17.
Flavonoids in 19 Cyrtomium, three Cyrtogonellum and two Phanerophlebia taxa were surveyed. Major flavonoids were flavonol O-glycosides based on kaempferol, quercetin, and sometimes myricetin, and C-glycosylflavones, such as isovitexin, vitexin, isoorientin, orientin and their O-glycosides. The C-methylflavanones, farrerol and cyrtominetin, and their 7-O-glucosides were isolated from Cyrtomium devexiscapulae and Cyrtomium laetevirens. Flavanones have been reported from Cyrtomium falcatum sensu lato. Though C. falcatum sensu lato is divided into four taxa, i.e. C. falcatum subsp. falcatum, C. falcatum subsp. australe, C. falcatum subsp. littorale, and C. devexiscapulae, the occurrence of the flavanones was restricted to C. devexiscapulae, and they did not occur in C. falcatum sensu stricto.  相似文献   

18.
Systematic Parasitology - Members of Forticulcitinae Blasco-Costa, Balbuena, Kostadinova & Olson, 2009 include endoparasites of mullet fishes distributed worldwide. Adult specimens were...  相似文献   

19.
The oribatid mite genus Galumna (Oribatida, Galumnidae) is recorded for the first time in Nepal. A new species, Galumna tetraporosasp. n., is described from soil of secondary mixed broadleaved forest. It is most similar morphologically to G. tokyoensis Aoki, 1966 and G. valida Aoki, 1994, however, it differs from both by the absence of interlamellar setae and the presence of two pairs of notogastral porose areas Aa. Galumna granalata Aoki, 1984 is redescribed on the basis of specimens from Nepal. Galumna floridae (Jacot, 1929) and G. hexagona Balogh, 1960 are transferred to the genus Notogalumna; G. mauritii Mahunka, 1978 is transferred to the genus Dimidiogalumna.  相似文献   

20.
Pollen morphology is an important source of information to increase systematic resolution in Asteraceae, especially in Vernonieae. Aiming to investigate if palynological traits give support to Caatinganthus, Strophopappus and Xiphochaeta as separate genera from Stilpnopappus, we used cluster analysis followed by a test of group sharpness. Further, ordination analysis was applied to detect informative pollen traits associated with the revealed groups. The analyses evidenced five groups: (G1) Caatinganthus rubropappus as a single-species group; (G2) species of Stilpnopappus; (G3) Xiphochaeta aquatica as a single-species group; (G4) Strophopappus bicolor, S. glomeratus, S. villosus, S. ferrugineus, S. pohlii and S. speciosus; (G5) Strophopappus bullatus and S. regnelli. The interruption in the middle of the muri in apertural lacunae explains the single-species group Caatinganthus rubropappus. The thickness of sexine, the type of apertures (porate or colporate), and spine dimensions (length, thickness and distance from each other) are the traits explaining differences between species of Stilpnopappus and Strophopappus. Equatorial lacunae give support to Xiphochaeta aquatica as a single-species group, despite the smaller size of pollen grains of this species as compared to the others species analyzed. The differences among pollen morphology give support to Caatinganthus, Stilpnopappus, Strophopappus and Xiphochaeta as genera according to the taxonomic classification currently accepted. The used approach was efficient to reveal individual pollen traits informative to explain the sharp groups, and was an effective alternative to the use of “pollen types”.  相似文献   

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