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Abstract

Fifty-eight species of echinoderms (excluding holothurians) are newly recorded from the southern Norfolk Ridge and the Three Kings Rise to the north of New Zealand. Two species of Asteroidea, in the genera Ceramaster and Pseudoceramaster, ceramaster are described as new. A total of 115 species of echinoderms, not counting the holothurians, are now known from this area. They include 14 crinoids, 35 asteroids, 41 ophiuroids, and 25 echinoids.  相似文献   

3.
Seven new species of Hydroptila (Trichoptera: Hydroptilidae) from Costa Rica are described: H. carara, H. maritza, H. osa, H. paradenza, H. maza, H. rastrilla, H. singri, and one from Panama, H. nusagandia. Ten additional species occurring in Costa Rica are recorded: H. brailovskyi Bueno-Soria, H. constricta Bueno-Soria, H. curvata Bueno-Soria, H. flinti Bueno-Soria, H. icona Mosely, H. meralda Mosely, H. mexicana Mosely, H. misolha Bueno-Soria, H. paschia Mosely, and H. veracruzensis Flint. In addition, illustrations of H. denza Ross and H. grenadensis Flint are included to help clarify the taxonomy of the denza species group. Finally, an illustrated key is provided for males of all species occurring in lower Central America.  相似文献   

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The leaf anatomy of two Bromeliaceae, Hechtia glomerata Zucc., a terrestrial xerophyte of arid zones, and Acehmea mexicana Baker, a tropical moist forest epiphyte, is compared; these species show adaptations to different extremes of adverse environmental conditions as to water uptake. The leaves of A. mexicana have more water storage tissue than those of H. glomerata; on the other hand, H. glomerata is capable of root absorption. In A. mexicana, modified nonfunctional stomata increase transpiration resistance. Also, this species shows more specialized foliar trichomes which permit the uptake of water and possibly of nutrients. The balance between transpiration and absorption rates is regulated in both species by the combined presence of peltate scales and stomata. The degree of adaptation to drought presented by epiphytic species is more complicated than that shown by terrestrial species. Epiphytic plants like A. mexicana may be derived from xerophytic species that have undergone readaptation to a humid climate. The conspicuous negative geotropism in the leaves of A. mexicana causes the formation of basal deposits of water, which play an important functional role in survival.  相似文献   

6.
A total of 25 species of echinoderms (four asteroids, six ophiuroids, five echinoids and ten holothurians) were recorded at Marino Ballena National Park, using 25 m2 quadrants, parallel to the coast, at seven sites. The ophiuroids were the most abundant group with 581 individuals and the asteroids the less abundant (48 individuals). Echinoderms densities were low, with the exception of the ophiuroids. Diversity, density and the number of groups were higher where sedimentation was lower. We suggest that sedimentation is having a negative effect on the diversity of echinoderms and on the development of the coral reefs in this park.  相似文献   

7.
Holothurian populations in the Caribbean have been significantly depleted in some areas, and others are still in danger to satisfy international markets. In Venezuela, this marine resource has been illegally exploited since the early 1990s. To contribute with their management and protection, this work analyzed the distribution, abundance and population structure of two commercial holothurians Isostichopus badionotus and Holothuria mexicana in Cubagua Island shores. A total of 52 stations were studied around the island during the year 2008. Surveys included visits to each station, for which a band transect of 50 m2 with four replicates were carried out. The results show that I. badionotus has a higher distribution on the East coast of the island, and is found over Thalassia testudinum beds or bivalve molluscs aggregations, with an average density of 0.011 ind/m2, C.I. 95% = 0.005-0.017, n = 122, and a general abundance estimated in 117 ind/ha. H. mexicana has been practically depleted (0.001 ind/m2 C.I. 95% = 0.0002-0.0013, 7.7 ind/ha, n = 8). We recommend the maintenance of the total ban adopted in 1997 to assure the protection of these species, mainly because no previous data supported the start of the fishery, and also, because the current densities are still very low when compared to other areas in Venezuela and the Caribbean. These are animals easy to catch, susceptible to overfishing, and with a very low recovery rate; thus, more control is required from the local authorities.  相似文献   

8.
Three species of Sabelliphilidae and four species of Lichomolgidae are reported as associates of scleractinian corals, nudibranchs, polychaetes, asteroids, and holothurians in Mauritius. A sabelliphilid from the polychaete Sabellastarte magnifica represents a new genus and species. Two previously described lichomolgids are recorded from new hosts. Species ranges are extended from Madagascar and New Caledonia to Mauritius.  相似文献   

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The species composition and patterns of distribution of echinoderms from the upper sublittoral zone to depth of 30 m in the southern and middle of Kola Bay in the Barents Sea were studied. In total, five species of starfishes, four species of brittle stars, three species of sea urchins and one species of holothurians were recorded. From the beginning of 20th century, under the impact of climate change and anthropogenic effect, the number of echinoderm species in the surveyed area decreased by two times, and the fauna has a more boreal character against the background of the domination of boreal-arctic species. The occurrence, population density and biomass of echinoderms, especially of common species, were several times less in the middle bend of the bay than in the southern one. The causes of this phenomenon have been discussed. The quantitative data (frequency of occurrence, number and biomass) for most of the species of echinoderms living in Kola Bay are given for the first time.  相似文献   

11.
Leishmania mexicana: amastigote hydrolases in unusual lysosomes   总被引:5,自引:0,他引:5  
Leishmania mexicana mexicana (M379) amastigotes were found to contain much higher activities than cultured promastigotes of five putative lysosomal enzymes: cysteine proteinase; arylsulfatase (EC 3.1.6.1); beta-glucuronidase (EC 3.2.1.31); DNase (EC 3.1.22.1), and RNase (EC 3.1.27.1). The release profiles of the first three of these enzymes from digitonin-permeabilized amastigotes suggests that they are located within organelles. Cytochemical staining for cysteine proteinase, using gold labeled antibodies and arylsulfatase, showed that both were present in large organelles previously named "megasomes." Comparative studies with L. mexicana amazonensis (LV78), L. donovani donovani (LV9), and L. major (LV39) revealed that L. mexicana amazonensis was similar to L. mexicana mexicana in possessing both high amastigote cysteine proteinase activity and large numbers of megasome organelles in amastigotes, whereas the other two species lacked both these features. The results suggest that the presence of numerous lysosome-like organelles in the amastigote is a characteristic of the L. mexicana group of parasites.  相似文献   

12.
Monoclonal antibodies have been produced that are specific for the reference stocks of Leishmania mexicana species and subspecies L. mexicana mexicana(L11, M379), L. mexicana amazonensis (WR303, H6, LV72), and L. mexicana pifanoi (L20). The specificities of these antibodies were confirmed by analyses employing an indirect radioimmune binding assay and 107 stocks of New World Leishmania. The molecules associated with these species- and subspecies-specific determinants have been characterized by Western blot analysis and consist of mainly low m.w. (11,000 to 50,000) membrane-associated components.  相似文献   

13.
Hymenaea mexicana sp. nov. is described in amber originating from mines of Chiapas, Mexico. The species is characterized by clawed showy petals with cordate bases and glabrous, verrucose ovaries with long hirsute hairs at their bases and margins on one side. This species is closely related to the extinct Hymenaea protera from Dominican amber, and together with it, is placed in the primitive section Trachylobium of the genus Hymenaea in the caesalpinoid legumes. The closest extant species to H. mexicana is H. verrucosa , a relict surviving in East Africa. These results challenge previous views that Mexican amber was produced by the South American species H. courbaril – H. intermedia , which belong to the advanced section of the genus.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 125–132.  相似文献   

14.
A total of 15 species of echinoderms (one asteroid, seven ophiuroids, five echinoids and two holothurians) were recorded at the Cahuita National Park reef lagoon, between September and October 2003, using a 1 m2 quadrant. The sites with coral substrate and algae were the most diverse, while those with seagrass and sand were the least. Ophiuroids were the most abundant group with 170 individuals, asteroids were the least abundant. Adding other studies and reports of echinoderms to this study, a total of 23 species have been found at Cahuita National Park, which is the most diverse area on the Caribbean of Costa Rica. We report nine new echinoderm records for Costa Rica's Caribbean.  相似文献   

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Phillips  L.E.  Nelson  W.A.  & Kraft  G.T. 《Journal of phycology》2000,36(S3):54-54
Padina is one of the most important genera in the coastal zone of the Gulf of California because of their biomass. Eight species have been recorded for the area: P. tetrastromatica , P. durvillaei , P. gymnospora , P. mexicana , P. caulencens , P. concrescens , P. crispata y P. vikeersiae based on taxonomic and floristic studies. Unfortunately, until today, a comparative study of all these species in a modern context was not available. Intensive surveys in 100 localities around the area yield more than 1000 specimes and 500 slides were analyzed and compared with relevant types. Taxonomic evaluations were developed using 16 characters commonly used in the literature. As a result of our analysis, only five characters can discriminate species. Based on character analysis and comparisons with proper type material, only three species can be recognized in the zone: P. concrencens , P. durvillaei and P. mexicana. In the case of P. crispata , we conclude that it is a heterotypic synonym for P. mexicna. But in the case of P. gymnospora, P. tetrastromatica and P. vikersiae , all previous records represent mis-identifications.  相似文献   

17.
Luminometry has been used to measure the respiratory burst of rabbit peritoneal neutrophils that is elicited by different forms and species of Leishmania and Herpetomonas. Mid-log phase and metacyclic promastigotes of L. major evoked large responses; that due to metacyclics was lower and slower, but they also bound in smaller numbers than mid-log phase cells. Promastigotes of L. mexicana mexicana also stimulated a large respiratory burst whereas amastigotes elicited little or none. Leishmania donovani promastigotes and culture forms of H. muscarum muscarum and H. m. ingenoplastis all evoked large responses by neutrophils. There was, however, very little response to L. mexicana mexicana promastigotes, L. donovani promastigotes or H. muscarum muscarum when they were added in large numbers. This 'inhibition' was not apparent with L. major.  相似文献   

18.
Crustaceans (5 families, 10 species) and fish (38 families, 101 species) were captured (October 27 through November 3, 1979) from the R/V "Vikheim" (Cruise 7901) in the Colombian Caribbean, at a 10-630 m, depth range (Metapeneopsis shrimp, 26 species of fishes new for the trawling bottom and, Squalus cubensis, Chlorophthalmus agassizi, and, Neoepinnula orientalis), new fishes records for the Caribbean of Colombia.  相似文献   

19.
The features of asexual reproduction, autotomy, and regeneration in five species of holothurians from the Order Dendrochirotida which live in the Nha Trang Bay of the South China Sea were studied. In Colochirus robustus, the ability to perform fission was corroborated. It was shown that Cladolabes schmeltzii can redivide without completing its regeneration after a previous division. This process is similar to the fragmentation of other holothurians. The features of autotomy and regeneration in Colochirus quadrangularis, Ohshimella ehrenbergi and Massinium magnum were described for the first time.  相似文献   

20.
The presence of a mosaic of habitats, largely determined by sea urchin grazing, across shallow rocky reefs may potentially influence in differences in the distribution patterns of invertebrates. The aim of this paper was to assess, using a correlative approach, whether the type of habitat influences the abundance patterns of holothurians in the eastern Atlantic. We hypothesized that abundances of large (> 10 cm) holothurians varied among four types of habitat (3 vegetated habitats with low abundances of the sea urchin D. antillarum vs. ‘barrens’ with hyperabundances of sea urchins), and that these differences were consistent at a hierarchy of spatial scales, including two islands and several replicated sites within each type of habitat and island. Three species of large holothurians were found, accounting for a total of 300 specimens. We found remarkable differences in abundances of holothurians between the ‘barrens’ and the three vegetated habitats. This pattern was strongest for the numerically dominant species, Holothuria sanctorii. Total abundances of holothurians were between 5 and 46 times more abundant in ‘barrens’ compared with the vegetated habitats. Inter-habitat differences were species-specific with some inconsistent patterns from one island to the other. The total abundances of holothurians tended to increase with the abundance of sea urchins within ‘barrens’. Our study suggests that there may be a link, at least for the dominant species Holothuria sanctorii, between the distribution and abundances of large holothurians and the habitat across shallow-waters of the eastern Atlantic.  相似文献   

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