首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Callipteris is a pantropical fern genus defined by two synapomorphies of its rhizome scales: 1) dark-castaneous to black borders, and 2) bifid marginal teeth. This monograph treats 15 neotropical species ofCallipteris that are further defined by the synapomorphy of anastomosing veins (free-veined species of the genus occur in the Neotropics and elsewhere). Three species are newly described here; the remaining 12 were previously classified inDiplazium. All the species ofCallipteris grow on wet forest floors at 100–2300 m. In the Neotropics the genus occurs from Guatemala to Bolivia, northern Brazil, and the Lesser Antilles. It has two centers of species richness. The first is the Chocó region on the western side of the Andes in Colombia and northwestern Ecuador. This region contains eight species, five of which are endemic. The second center is the mountains of Costa Rica and Panama, where six species occur, three of which are endemic. Only one species, an endemic, occurs in the Lesser Antilles in Martinique, St. Vincent, and Grenada. Four species occur only on the eastern side of the Andes, and these apparently represent at least two separate dispersal events from the western side of the Andes.  相似文献   

2.
A new species, Chactas moreti sp. n., is described from Ecuadorian Amazonia. It can be distinguished from Chactas mahnerti Lourenço, 1995, the other known species of this genus from Ecuador by its smaller body size, distinct morphometric values, overall darker blackish-brown coloration, totally smooth vesicle, and a concave anterior margin of carapace. This is the second confirmed record of the genus Chactas Gervais from Ecuador. The geographical pattern of distribution of the genus is also discussed.  相似文献   

3.
Pentaplaris davidsmithii from Peru and Bolivia andP. huaoranica from Ecuador are described and compared to the only other species previously known in the genus,P. doroteae from Costa Rica. Morphological and palynological characters support the inclusion ofPentaplaris in core Malvales while suggesting that the original assumption that the genus belonged in Tiliaceae-Brownlowieae cannot be maintained.Pentaplaris, which comprises three isolated and evidently rare species, probably belongs to the malvoid-bombacoid alliance, but its position within this clade ramains unresolved.  相似文献   

4.
Aulopus bajacali, described from the eastern Pacific Ocean from a single specimen, is redescribed. It is now known from over 400 specimens. It is the only Pacific species ofAulopus belonging with the Atlantic species group ofA. nanae, A. filamentosus, andA. cadenati. It shares a short dorsal-fin base and some color pattern characters with this group. New distribution records from Ecuador and the Galapagos Islands extend its range; it is now known from mid-Baja California (25°N) to about 3°S in the eastern central Pacific.  相似文献   

5.
Phaedranassa viridiflora (Amaryllidaceae) is an endemic and endangered plant restricted to the Northern Andes in Ecuador. It is known in three locations where it is sympatric with other Phaedranassa species. Phaedranassa viridiflora is the only species of the genus with yellow flowers. We analyzed 13 microsatellite loci to elucidate the genetic structure of the populations of P. viridiflora. Our results provided the first evidence of natural hybridization in the genus (between P. viridiflora and P. dubia in the Pululahua crater of northern Ecuador). The central and southern populations did not show hybridization. Genetic diversity was the highest in the Pululahua population. Central and southern populations have a higher proportion of clones than Pululahua. Bayesian and cluster analysis suggest that the yellow flower type evolved at least three times along the Ecuadorean Andes. In contrast to other Phaedranassa species, Phaedranassa viridiflora shows lower genetic diversity, which is likely related to a vegetative reproductive strategy.  相似文献   

6.
The genusAspasia (Orchidaceae: Oncidieae) consists of five species of epiphytic orchids of Central and South America. The genus is compared with closely related genera of the tribe Oncidieae.Aspasia epidendroides is found in Nicaragua, Costa Rica, and western Panama.Aspasia principissa is found in central and eastern Panama and adjacent Colombia.Aspasia psittacina is endemic to western Ecuador.Aspasia variegata is found in Colombia, Venezuela, Trinidad, Guyana, Surinam, and Brazil.Aspasia lunata is known only from Brazil.  相似文献   

7.
We describe a new species native to Ecuador and Peru, Miconia complanata . This species has been collected from two different localities: Parque Nacional Podocarpus (Ecuador) and Cordillera del Cóndor (Ecuador and Peru). The strongly quadrangular to winged stem, ridged nodes and coriaceous leaves make this species distinctive even within a large genus.  相似文献   

8.
9.
10.
At least two species of Amazonian sedges (piripiri, i.e., Cyperus articulatus andC. prolixus, Cyperaceae) are widely utilized for various medicinal purposes, including birth control and induction of labor, and in hallucinogenic preparations. Examination of herbarium specimens collected from throughout South America and of living specimens collected in Ecuador has revealed that plants are infected by the systemic, ascomycetous fungusBalansia cyperi. This fungus is classified in the Clavicipitaceae and is known to infect only six species ofCyperus, including both North and South American species. Pure cultures of the fungus were obtained from two species of piripiri from Ecuador andC. virens from southern USA, and grown in submerged liquid culture. Extracts of the liquid medium revealed several unidentified ergot alkaloids. Current and past pharmacological uses of ergot alkaloids are consistent with uses of piripiri, suggesting a fungal basis for the ethnobotanical utilization of piripiri in Amazonia.  相似文献   

11.
Two new species ofBejaria,B. zamorae from Ecuador andB. infundibula from Peru, are described, illustrated, and compared with other species of the genus.  相似文献   

12.
13.
Triassic ichthyosaurs are very widespread and diverse but most taxa are poorly known. New discoveries, such as described in this paper, underscore the first statement but only slowy invalidate the second. The first associated skeleton of the unusual durophagous ichthyosaurOmphalosaurus (O. wolfi) is reported from the Middle Triassic (earliest Ladinian) of the northern Alps. The vertebrae are of the ichthyosaurian type, firmly establishing the ichthyosaurian affinities of the genus. A round bone from the Muschelkalk of Franconia, Germany, is identified and described as a left humerus ofOmphalosaurus sp. These finds greatly extend the paleogeographic and temporal range ofOmphalosaurus which previously was only known from the western cratonic margin of North America and from Spitsbergen. The new records ofOmphalosaurus allow a revised differential diagnosis of the genus and a revision of its species. Valid species ofOmphalosaurus areO. nettarhynchus, O. nevadanus, andO. wolfi. In conjunction with such new insights into Triassic ichthyosaur distribution, it is necessary to address the validity of the poorly known genera such as the Middle TriassicPessosaurus. This taxon must be considered invalid because it lacks diagnostic characters. In assessing progress in research on Triassic ichthyosaurs and their paleobiogeography, it becomes apparent that supra-specific diversity appears largely known, at least for the pre-Norian record of North America, Europe, and East Asia.  相似文献   

14.
Peter Goldblatt 《Brittonia》1975,27(4):373-385
The native bulbous Iridaceae of North America excluding Mexico comprise seven species in four genera. The type species ofAlophia Herb. (1836) is shown to belong toEustylis Engelm. & Gray (1836), hence the latter genus is reduced to synonymy. The well known genusAlophia (sensu auct. non Herb.) (Herbertia Sweet) now takes the nameTrifurcia. As a result of the new interpretation ofAlophia, new combinations are made for the North American and Latin American species ofTrifurcia andAlophia. New chromosome counts are given forNemastylis floridana (2n = 56) andTrifurcia lahue (2n = 56).  相似文献   

15.
Up to nowMachimosaurus was known only from isolated teeth. Its systematic position was uncertain. Recently discovered remains ofMachimosaurus from the Upper Jurassic of Portugal allow a reconstruction of the skull. This find proves thatMachimosaurus belongs to the crocodilian family Teleosauridae. The genus comprises the only speciesMachimosaurus hugii H. v.Meyer. The speciesMachimosaurus mosae Sauvage & Liénard is based on heterogeneous material and is unmaintainable. Osteological characteristics show that the environment ofMachimosaurus was the open seas.  相似文献   

16.
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   

17.
John F. Pruski 《Brittonia》1991,43(4):264-268
Described and illustrated from Cerro de la Neblina in T. F. Amazonas, Venezuela is the fifth known Guayanan species ofPentacalia, a genus recently reinstated from synonymy withinSenecio. The distinctions between these two genera are briefly discussed as are the distinctions betweenPentacalia and similar genera. A key to the new species,Pentacalia neblinesis, and the other species ofPentacalia from the Guayana Highland is given.  相似文献   

18.
Isaya Higa  Yoshiaki Fuyama 《Genetica》1993,88(2-3):129-136
To reveal the genetic mechanism of host selection in a monophagous fruit flyDrosophila sechellia, olfactory responses and oviposition preferences of this species were compared with those of closely related polyphagous species,D. simulans andD. melanogaster. Adult flies ofD. sechellia were strongly attracted to the ripe fruit ofMorinda citrifolia which is known to be the sole breeding site of this species. They were also attracted to the odor ofn-caproic acid which is contained in the ripe fruit ofM. citrifolia and is presumably responsible for the characteristic odor of the fruit. In contrast,D. simulans andD. melanogaster showed a strong repulsion ton-caproic acid. In parallel with the olfactory responses,D. sechellia females laid eggs preferentially on a medium containingn-caproic acid, to which the other two species showed an aversion. Genetic analyses using the hybrid progeny betweenD. sechellia andD. simulans suggested that the species differences in these behaviors are controlled by gene(s) located on the second chromosome.  相似文献   

19.
Three of the five known species ofLepidopus occur in the eastern Pacific.Lepidopus manis sp. nov. is described from a single specimen from the Galápagos Islands. The holotype ofL. xantusi Goode et Bean, 1895, supposedly from Cape San Lucas, Lower California, is shown to be conspecific withL. caudatus (Euphrasen, 1788). The species heretofore reported under the nameL. xantusi is described, and namedL. fitchi sp. nov. It ranges from Oregon to the Gulf of California and occurs disjunctly in southern Ecuador and northern Peru. A key to the described species ofLepidopus is given and certain morphological features ofL. caudatus are described. Geographic variability ofL. caudatus andL. fitchi is discussed.  相似文献   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号