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1.
Six kinorhynchs were found in the stomachs of the Argentine red shrimp, Pleoticus mulleri (Bate, 1888) from the Argentine coast of Patagonia. Three new species are described: Condyloderes storchi n. sp., Pycnophyes argentinensis n. sp. and P. neuhausi n. sp. A fourth species, Kinorhynchus anomalus Lang, 1953 was previously known only from the coast of Chile. This is the third known record of kinorhynchs documented as a food source. Condyloderes storchi, n. sp. is the fourth new species in this genus. It is distinguished by its paradorsal cuspidate spines on segments 7 and 9, lateral accessory and ventrolateral spines on segments 3, 6, 7, 10 and 11. P. argentinensis, n. sp. has nearly equal sternal width for segments 3–11 (about 7% of the trunk length), episternal plates with three distinct areas along the anterior margin, mid-sternal plate with even margin, mid-dorsal spinose protrusions along the terminal borders of segments 11 and 12, and lateral terminal spines 176 μm long, about 21% of trunk length. P. neuhausi, n. sp.has a prominent posterior elongation of the tergal plate of segment 3, uneven lateral margins of the mid-sternal plate, a maximum sternal width at segment 3, no mid-dorsal spinose processes and mid-ventral thickenings on segments 10–12.  相似文献   

2.
Based on the results of morphological and DNA sequence (partial D1–D3/D7–D8 nuLSU and partial nuSSU-ITS1-5.8S rDNA) data, three species of Plasmopara are revised and reclassified. A species of Plasmopara parasitic on Scorzonera, invalidly published several times, is assigned to a new genus and species under Novotelnova scorzonerae. Plasmopara euphrasiae sp. nov. is segregated from P. densa, and P. centaureae-mollis is revised and relegated to synonymy of Bremia centaureae. All taxa are described and illustrated.  相似文献   

3.
Five species of Cervonema and four species of Laimella are described from the Strait of Magellan and the Beagle Channel, Chile, six species of which are new to science. Cervonema chilensisn. sp. and Cervonema hermanin. sp. are separated from other known species of Cervonema by a short cervical region (less than one head diameter from the front end to the anterior border of the amphids). Cervonema chilensisn. sp. is characterised by a tail length of 5 anal diameters with posterior half filiform; Cervonema hermani n. sp. is characterised by a tail length of 6–9 anal diameter and posterior part (75%) cylindrical. Cervonema shiaen. sp. is characterised by the cephalic seta 4 m long, amphids 9–10 m in diameter; spicules 16 m long and 0.8–0.9 abd; tail 4.7–5.4 anal diameter and 50% posterior part filiform; 4–5 minute precloacal supplements. Laimella subterminatan. sp. is characterised by the subterminal position of the buccal cavity which separates it from the other species of the genus. Laimella annaen. sp. is characterised by the head diameter 9–11 m, cephalic setae and external labial setae 9 + 5 m long, respectively, amphids 7 m in diameter; spicules 28–30 m long; tail 14–17 anal diameter and posterior part (75%) filiform; 5 precloacal supplements. Laimella sandraen. sp. is very close to Laimella annaen.sp. in having similar cephalic sensilla, amphids and spicules. Laimella sandraen. sp., however, can be separated from L.annaen. sp. by the shape of head and the structure of sperm cells, the total body length and the cylindrical part of tail. Cervonema papillatum Jensen, 1988, C. tenuicauda (Stekhoven, 1950) and L. longicauda Cobb, 1920 are found in this area as well. The key of all known species of Cervonemaand Laimellais presented.  相似文献   

4.
Zhang  E.  He  Shun-Ping  Chen  Yi-Yu 《Hydrobiologia》2002,487(1):207-217
Placocheilus is re-diagnosed on the basis of oromandibular structures compared to those of closely related groups. It is represented in China by three species restricted to Yunnan, namely P. caudofasciatus from the Tengtiaohe River (Nam Na), P. cryptonemus from the Nujiang Rive (upper Salween River basin), and P. robustus, herein described as a new species from the Yuanjiang River (Red River basin). P. robustus n. sp. is differentiated from its congeners in having a stout caudal peduncle (depth 72.4–82.5% of its length) and the medium-sized scaleless midventral region of belly extended slightly beyond halfway from the pectoral- to pelvic-fin origin. It is further distinguished from P. caudofasciatusin having a coarsely crenulated rostral fold with 18–23 indentations on its distal margin and a smaller mental adhesive disc (length 66.7–71.4% of its width and 37.0–43.1% of the head length).  相似文献   

5.
Four species of turbellarian temnocephalan symbionts (Platyhelminthes: Temnocephalida) are reported for the first time from the external surfaces of Cherax quadricarinatus, a freshwater crayfish from northern Australia. Three of these species — Temnocephala rouxii Merton, 1913, Notodactylus handschini (Baer, 1945), and Diceratocephala boschmai Baer, 1953 — are known previously from related crayfish in New Guinea. The newly discovered fourth species, Decadidymus gulosus n. gen., n. sp., has an unusual combination of characters linking it with both the Temnocephalidae and the Scutariellidae. Together the four species possess an array of characters that challenges current concepts of families in the order. D. boschmai has an almost completely ciliated epidermis, a feature otherwise unknown in the order.  相似文献   

6.
The production of aboveground tissue of three alder species (Alnus crispa (Ait.) Pursh,A. rugosa (Du Roi) Spreng. andA. glutinosa (L) Gaertn.) on four sites ranged from 0.4 t ha–1 yr–1 to 4.0 t ha–1 yr–1 after four growing seasons. Large differences were observed among the four sites studied and among species. Soil nutrient levels affected the biomass production and foliar symptoms of P and Mg deficiency occurred withA. crispa andA. rugosa. Because of their poor aboveground biomass production (0.4–1.4 t ha–1 yr–1),A. crispa andA. rugosa should be used mainly as nurse trees. For its higher potential for biomass production (up to 4.0 t ha–1 yr–1), and its apparent higher ability to use P and Mg on deficient sites,A. glutinosa should be used preferably toA. crispa andA. rugosa for the production of biomass.  相似文献   

7.
Decraemer  Wilfrida  Gourbault  Nicole 《Hydrobiologia》2000,429(1-3):25-47
Four new species of Metepsilonema are described from sublittoral stations from the Channel and are mainly characterized: M. volutum sp.nov. by the large body size for the genus up to 460 m, 118–121 well overlapping annuli and wide multispiral amphids; M. amphidoxum sp.nov. by 127–133 shortly overlapping annuli and sexual dimorphism in amphid size; M. comptum sp.nov. by 133–140 non-overlapping annuli, anteriormost annuli provided with a wide lumen and borders ornamented with ridges and M. corrugatum sp.nov. by 108–111 overlapping annuli provided with ridges). Additional information is provided for M. callosum together with a discussion on intraspecific variability. A new species of Metepsilonema spec. based on females only, is described but remain unnamed. M. comptum sp.nov. and M. corrugatum sp.nov. are also occurring in the Mediterranean Sea. A polytomous key to species level is presented.  相似文献   

8.
Rhabdias rhampholeonis n. sp. from Rhampholeon (Rh.) spectrum, Cameroon, and Rhabdias mariauxi n. sp. from Rieppeleon brevicaudatus, Tanzania, are the first lung worms from leaf chameleons. The new species are similar to the majority of species parasitic in chamaeleonids by having a long (≥10 mm) and thick body (≥500 µm), long oesophagus (≥800 µm), wide buccal capsule (≥40 µm) and low buccal ratio (<0.5). They most closely resemble Rhabdias chamaeleonis and Rhabdias cristati parasitic in Trioceros spp. from East Africa and Cameroon, respectively. Main distinctive characters are a buccal capsule composed of two segments and the head shape. The dorso-ventrally flattened buccal capsule of R. mariauxi n. sp. is unique in Rhabdias parasitising Chamaeleonidae. Sequences of the 12S rDNA and mitochondrial cytochrome c oxidase subunit 1 (coxI) genes were obtained and compared to those of Rhabdias okuensis, the only sequences published for chamaeleonid lung worms. The smallest nucleotide interspecific distances were found between R. mariauxi n. sp. and the former species of Trioceros from Cameroon. Hermaphroditism in females in the lungs, and R. mariauxi n. sp. free-living stages are like in other species from Chamaeleonidae, but the number of infective larvae produced per free-living female (one or two) was not fixed.  相似文献   

9.
Toxicity of Pfiesteria piscicida (strain CAAE #2200) in the presence of fish (juvenile hybrid tilapia, Oreochromis sp., total length 3–6 cm) has been maintained in the laboratory for 19 months by serial transfer of toxic cells using a modified maintenance protocol. Toxicity was re-induced when toxin-producing P. piscicida cells were separated from fish and cultured on algal prey for 50 days and then re-introduced to new tanks containing fish. We confirmed toxicity in a strain of P. shumwayae (strain CAAE #101272). Toxicity to fish was demonstrated in culture filtrates (0.2 μm) derived from cultures of both Pfiesteria spp., however, it was markedly reduced in comparison to unfiltered water. Filtrates retained toxic activity when stored at −20 °C for up to 6 months. Toxicity to fish was retained when filtrates were held at room temperature for 48 h, at 70 °C for 30 min or at 88–92 °C for 2 h. P. piscicida killed all finfish species tested. Grass shrimp (Paleomonetes pugio; adult 2–3 cm), blue crab (Callinectes sapidus; juvenile 4–7 cm) and brine shrimp (Artemia sp.; 18–24 h post-hatch) were unaffected by concentrations of toxin(s) that killed juvenile tilapia in 4–24 h. Ichthyotoxic activity of filtrates from fish-killing cultures and stability of the toxic activity were similar among P. piscicida and P. shumwayae. These results confirm previously reported observations on toxicity of P. piscicidaand P. shumwayae to finfish. We have maintained toxicity in the laboratory for longer periods than have previously been routinely achieved, and we have demonstrated that the toxic activity is heat stable. In contrast to previous studies with other toxic P. piscicida strains, we did not observe toxic activity to blue crabs or other crustaceans.  相似文献   

10.
A cladistic analysis of the West Palaearctic Scopaeina Mulsant & Rey, 1878 (Coleoptera, Staphylinidae: Paederinae) is presented along with bionomic and biogeographic information. A total of 76 morphological characters were coded for the 88 currently known West Palaearctic species, except for S. bifossicapitata (Outerelo & Oromi, 1987). Results show that Scopaeina comprises two well-supported monophyletic groups in the West Palaearctic, Micranops Cameron, 1913 and Scopaeus Erichson, 1840, which are considered to represent distinct genera. Phylogenetic relationships to Orus Casey, 1884, distributed in North and South America, are briefly discussed. Whereas Micranops is only represented by M. pilicornis (Baudi, 1869) in the region under study, 87 species of Scopaeus are currently known from the West Palaearctic. Within Scopaeus, the cladistic analysis yielded many well-supported monophyletic species groups, most of which are restricted to the West Palaearctic. However, except for Hyperscopaeus Coiffait, 1984, they are not in agreement with the widely used subgeneric concept sensu Coiffait (1952–1984). The following polyphyletic subgenera are consequently synonymized: Alloscopaeus Coiffait, 1968, Anomoscopaeus Coiffait, 1968, Geoscopaeus Coiffait, 1960, and Hyposcopaeus Coiffait, 1960 synn. n. = Scopaeus Erichson, 1840. Nivorus Herman, 1965, and Microscopaeus Coiffait, 1981 synn. n. = Micranops Cameron, 1913. The monotypical genus Coecoscopaeus Coiffait, 1984, established for C. coecus (Peyerimhoff, 1906), is excluded from Scopaeina. Scopaeus mitratus perroti Ochs, 1953 is raised to species rank, and S. nigellus Wollaston, 1864, formerly a synonym of S. minimus Erichson, 1939, is revalidated. Finally, we present a catalogue of species and synonyms of West Palaearctic Scopaeina along with distributional data and five new synonymies of species group names: S. bordei Peyerimhoff, 1914 syn. n. = S. portai Luze, 1910; S. tassiliensis Jarrige, 1958, S. mauretanicus Coiffait, 1960 synn. n. = S. crassipes Wollaston, 1867; S. saoudiensis Coiffait, 1981 = S. sinaicus Coiffait, 1970; S. mateui Coiffait, 1953 syn. n. = S. didymus Erichson, 1840. A lectotype is designated for S. didymus Erichson, 1840.See also Electronic Supplement (Parts 13) at http://www.senckenberg.de/odes/02-02.htm  相似文献   

11.
The chromosome numbers of seven species ofPelargonium sect.Eumorpha have been determined from material of known wild origin, and karyotypic comparisons have been made. Within the section there is variation in basic chromosome number (x = 4, 8, 9, 11), variation in chromosome size, and two species have polyploid races. The three species with chromosome numbers based on x = 11 have the smallest chromosomes (1.0–1.5 µm); chromosomes are larger (1.0–3.0 µm) in the other species.P. elongatum has the lowest chromosome number in the genus (2n = 8).P. alchemilloides is exceptional in that it has four cytotypes, 2n = 16, 18, 34 and 36, and the form with 2n = 36 has large chromosomes (2.0–5.0 µm). Evidence from a synthesized hybrid suggests thatP. alchemilloides with 2n = 16 may be of polyploid origin. The three species based on x = 11 appear to be more closely related to species from other sections ofPelargonium that have the same basic chromosome number and small chromosome size, rather than to other species of sect.Eumorpha.  相似文献   

12.
The potential of three estuarine macroalgae (Ulvarotundata, Enteromorpa intestinalis andGracilaria gracilis) as biofilters for phosphate ineffluents of a sea bass (Dicentrarchus labrax) cultivationtank was studied. These seaweeds thrive in Cádiz Bay and were alsoselected because of their economic potential, so that environmental andeconomicadvantages may be achieved by future integrated aquaculture practices in thelocal fish farms. The study was designed to investigate the functioning of Pnutrition of the selected species. Maximum velocity of phosphate uptake (2.86mol PO4 g–1 dry wth–1) was found in U. rotundata.This species also showed the highest affinity for this nutrient. At low flowrates (< 2 volumes d–1), the three species efficientlyfiltered the phosphate dissolved in the waste water, with a minimum efficiencyof 60.7% in U. rotundata. Net phosphate uptake rate wassignificantly affected by the water flow, being greatest at the highest rateassayed (2 volumes d–1). The marked decrease in tissue P shownby the three species during a flow-through experiment suggested that growth wasP limited. However, due to the increase in biomass, total P biomass increasedinthe cultures. A significant correlation was found between growth rates and thenet P biomass gained in the cultures. A three-stage design under low water flow(0.5 volumes d–1) showed that the highest growth rates (up to0.14 d–1) and integrated phosphate uptake rates(up to 5.8 mol PO4 3– g–1dry wt d–1) were found in E.intestinalis in the first stage, with decreasing rates in thefollowing ones. As a result, phosphate become limiting and low increments oreven losses of total P biomass in these stages were found suggesting thatphosphate was excreted from the algae. The results show the potential abilityofthe three species to reduce substantially, at low water flow, the phosphateconcentration in waste waters from a D. labrax cultivationtank, and thus the quality of effluents from intensive aquaculture practices.  相似文献   

13.
Diel activity patterns in Metapenaeus and Penaeus juveniles   总被引:1,自引:0,他引:1  
Small (5–10.9 mm carapace length), medium (11–15.9 mm), and large (16–20.9 mm) juveniles of Metapenaeus anchistus, Metapenaeus sp., Penaeus monodon and P. merguiensis were stocked individually in glass tanks provided with sand substrate, sea water, artificial bamboo shelter, aeration and food. The seven activity types (recorded for each shrimp hourly for 24 h) were classified as below (burrowing) or above substrate (swimming, walking, stationary, in shelter, feeding and cleaning). Shrimp juveniles exhibited a strong diel periodicity — emergence and activity at night and burrowing in the day. The chi-square test showed that type of activity (above/below substrate) was associated with period (light/dark). Diurnal burrowing was greater among Metapenaeus than Penaeus; inversely, above substrate activities were more frequent for Penaeus species compared to Metapenaeus. Feeding was the major above substrate and nocturnal activity for M. anchistus, Metapenaeus sp. and P. monodon. Only P. Monodon used the shelter consistently. Frequency of the 7 activity types was dependent on juvenile size for Penaeus, e.g., the preference for shelters shifted to burrowing with increase in size in P. monodon. Results are discussed in relation to the importance of mangrove habitats in providing shelter to penaeids, in particular the mangrove-associated P. monodon and P. merguiensis.  相似文献   

14.
Crude aqueous methanol extracts obtained from 31 species of various marine organisms (including flora land faunal), were screened for their antifungal activity against food poisoning strains of Aspergillus. Seventeen species exhibited mild (+ =zone of inhibition 1–2 mm) to significant (+++ =zone of inhibition 3–5 mm) activity against one or the other strain under experiment. However, extracts of 12 species were active against all the three strains. Organisms like Salicornia brachiata(obligate halophyte), Sinularia leptocladus(Soft coral), Elysia grandifolia (Mollusks),Gorgonian sp. 2 and Haliclona sp. exhibited significant (inhibition zone of 3–5 mm) antifungal activity against one or the other strains. However,extracts of A. ilicifolius, Amphiroa sp.,Poryphyra sp., Unidentified sponge, Suberites vestigium, Sinularia compressa,Sunularia sp., Sinularia maxima, Subergorgia suberosa, Echinogorgia pseudorassopo and Sabellaria cementifera were mild (inhibition zone of 1–2 mm) to moderate(inhibition zone of 2–3 mm) active against the respective strains. The growth of A. japonicuswas significantly inhibited by the extracts ofS. leptocladus (r = 0.992, p < 0.0001)and E. grandifolia (r = 0.989, p < 0.0001).This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

15.
Broekhuizen  N.  Parkyn  S.  Miller  D.  Rose  R. 《Hydrobiologia》2002,477(1-3):181-188
Much of the variation in individual growth rates can be attributed to differences in individual feeding rates. Therefore, in order to build predictive models of individual, or population growth, the factors influencing an individual's feeding rate must be described. An important determinant of the feeding rate is the relationship between the local abundance of food and the individual's ingestion rate – otherwise known as the functional response. We determined functional responses for two species of invertebrate grazers: the snail Potamopyrgus antipodarum and the mayfly Deleatidium sp., by measuring their assimilation rate with increasing densities of radiolabelled periphyton. The assimilation rates were consistent with the Holling Type II or Michelis Menten functional response curve. The parameters of the functional response yielded estimates of the search area and handling time for the stream invertebrates. Our functional response data indicate that the half-saturation food density for P. antipodarum and Deleatidium sp. were 980 mg and 3200 mg AFDM m–2, respectively, suggesting that Deleatidium growth may be subject to food limitation more often than is P. antipodarum – despite the lower assimilation efficiency of the latter species.  相似文献   

16.
Saponaria stenopetala sp.n. in Eastern Afghanistan is close toS. pachyphylla Rech. f. andS. subrosularis Rech. f.—The nearest allies ofS. makranica sp.n. from Western Pakistan and Southeastern Iran areS. kermanensis Bornm. andS. floribunda (Kar. & Kir.)Boiss.
Flora Iranicae praecursores 36–37. — Praecursores praecurrentes in Pl. Syst. Evol.139, 313–317 (1982).  相似文献   

17.
The objective of this study was to determine the effect of two endophytic bacterial elicitors (Pseudomonas sp. and Enterobacter sp.) on the production of alkaloids in protocorm-like bodies (PLBs) of Pinellia ternata Breit. Both bacterial strains increased the growth rate of P. ternata PLBs. Pseudomonas sp. promoted the differentiation of the PLBs, whereas Enterobacter sp. inhibited PLB differentiation. The bacterial strains increased guanosine production in PLBs by 9–166%, inosine production by 2–33%, and trigonelline production by 114–1140% compared to the control. For Pseudomonas sp., guanosine and trigonelline production was greater when bacterial extracts were added to the PLB suspension cultures rather than living cells (co-culture treatment). Inosine production was similar in both the bacterial extract and co-culture treatments. For the Enterobacter sp., guanosine, inosine, and trigonelline production tended to be greatest when living cells were added to the PLB suspension cultures rather than bacterial extracts. These results suggest that Pseudomonas sp. and Enterobacter sp. could increase alkaloid yield from P. ternata under field or tissue culture conditions. We also observed that Pseudomonas sp. and Enterobacter sp. produced some of the same alkaloids as their host plants. Additional study needs to be done to determine if these endophytic bacteria could be used to produce alkaloids in the fermentation industry.  相似文献   

18.
Mielke  Wolfgang 《Hydrobiologia》2001,445(1-3):77-83
Loureirophonte psammophila n. sp. was collected from coarse sediments of a beach near La Paz, Baja California, Mexico. The species belongs to the subterranea-group as defined by Fiers (1993). It differs from the other representative of the group, L. subterranea (Lang, 1965) in the presence of an outer dentiform process on 2nd segment of the antennula, the chaetotaxy of P.2–P.5 and the 1-segmented male endopodite P.4. A map with the distribution of the eleven species known so far is provided.  相似文献   

19.
H. tageae sp. n. and Halicyclops ytororoma sp. n. are described from the intertidal interstitial water of Brazilian beaches. H. tageae is distinguished from all congeneric species by the number of setae on legs 1–4 endopodite 2 (1, 1, 2, 2) and by possessing a reduced inner spine on the leg 5 exopodite. It shares with H. brevispinosus, H. pusillus and H. canui the spine formula 2, 3, 3, 3 on exopodite 3 of swimming legs 1–4. H. ytororoma closely resembles H. gauldi and differs from this species by having 4 setae on leg 1 endopodite 3; H. gauldi has 3 setae on this segment.This is the first record of Halicyclops from marine interstitial water in Brazil.  相似文献   

20.
In consideration of their origin the adaptive strategies of the evergreen species of the Mediterranean maquis were analysed. Rosmarinus officinalis L., Erica arborea L., and Erica multiflora L. had the lowest net photosynthetic rate (PN) in the favourable period [7.8±0.6 mol(CO2) m–2s–1, mean value], the highest PN decrease (on an average 86 % of the maximum) but the highest recovery capacity (>70 % of the maximum) at the first rainfall in September. Cistus incanus L. and Arbutus unedo L. had the highest PN during the favourable period [15.5±5.2 mol(CO2) m–2s–1, mean value], 79 % decrease during drought, and a lower recovery capacity (on an average 54 %). Quercus ilex L., Phillyrea latifolia L., and Pistacia lentiscus L. had an intermediate PN in the favourable period [9.2±1.3 mol(CO2) m–2s–1, mean value], a lower reduction during drought (on an average 63 %), and a range from 62 % (Q. ilex and P. latifolia) to 39 % (P. lentiscus) of recovery capacity. The Mediterranean species had higher decrease in PN and stomatal conductance during drought and a higher recovery capacity than the pre-Mediterranean species. Among the pre-Mediterranean species, P. latifoliahad the best adaptation to long drought periods also by its higher leaf mass per area (LMA) which lowered leaf temperature thus decreasing transpiration rate during drought. Moreover, its leaf longevity determined a more stable leaf biomass during the year. Among the Mediteranean species, R. officinalis was the best adapted species to short drought periods by its ability to rapidly recover. Nevertheless, R. officinalis had the lowest tolerance to high temperatures by its PN dropping below half its maximum value when leaf temperature was over 33.6°C. R. officinalismay be used as a bioindicator species of global change.This revised version was published online in March 2005 with corrections to the page numbers.  相似文献   

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