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1.
Fosshagen  Audun  Iliffe  Thomas M. 《Hydrobiologia》1994,294(1):17-22
The insects of a small and cold aestival stream in northern Sweden were studied from semiquantitative kick-samples taken every ten days throughout the ice-free season in 1987. The stream froze solid at least in some sections in some winters. In addition to dipterans that were only identified to the family level, five ephemeropteran, four plecopteran, 11 coleopteran (Dytiscidae), and four trichopteran (Limnephilidae) species were found. Baetis bundyae Lemkuhl, Heptagenia orbiticola Kluge (Ephemeroptera), Nemoura cinerea (Retzius) (Plecoptera), Hydroporus palustris (L), Agabus setulosus (J. Sahlberg) (Coleoptera), Anabolia concentrica (Zetterstedt), Limnephilus coenosus Curtis, and Micopterna sequax McLachlan (Trichoptera) were all common. Malaise trap data are given for Plecoptera. The two ephemeropteran species Heptagenia orbiticola and Metretopus alter Bengtsson, and the plecopteran species Nemoura viki Lillehammer were recorded for the first time in Sweden. The remarkable species composition was attributed to the harsh abiotic and poorly studied environment. We predicted that the larval composition of this stream was representative for aestival streams in northernmost Fennoscandia.  相似文献   

2.
The larva of Beraea dira McLachlan, 1875 is described. An attempt is made to include the larva of Beraea dira in an existing key for larvae of Trichoptera published by Waringer and Graf (1997). Some taxonomical, zoogeographical and ecological notes on this species are included.  相似文献   

3.
  • 1 We examined the potential selective pressures exerted by different types of predators on morphological prey defences using the case-building larvae of the limnephilid caddisfly, Limnephilus frijole. The predators were a predaceous minnow, Gila pandora, and an aeschnid dragonfly naiad, Oplonaeschna armata.
  • 2 The influence of larval case design on vulnerability to predators was evaluated in a series of laboratory experiments. Larval L. frijole were collected from a stream without fish or dragonflies. In the laboratory, larvae still occupying their field-built cases were exposed to the two predators, with which L. frijole co-occurs in other streams. Following 24 h exposure of caddisfly larvae to a specific predator, the pre-trial case length, case strength, case width, and case composition of victims and survivors were compared.
  • 3 Principal components analysis (PCA) indicated substantial independent variation for all four case parameters in the study population. The cases of larvae surviving exposure to either dragonfly naiads or fish were significantly stronger and wider than cases of victims of predation. Cases of survivors were also longer and had a greater mineral fraction than those of victims, but differences were either marginally significant or not significant.
  • 4 These results demonstrate that specific aspects of case design affect the vulnerability of caddisfly larvae. In addition, predaceous fish and predaceous invertebrates, using different predation techniques, may exert similar selective pressures on these defenses. Case aspects influencing vulnerability in these experiments are broadly consistent with natural variation in case design associated with predator-rich and predator-free habitats for related caddisfly species.
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4.
The caddisfly fauna of 13 protected areas in Belarus is studied. A total of 97 species from the following 12 families are recorded: Hydroptilidae (6 species), Ecnomidae (1), Polycentropodidae (11), Pshychomyidae (1), Hydropsychidae (5), Phryganeidae (12), Brachycentridae (1), Limnephilidae (41), Sericostomatidae (1), Molannidae (1), Beraeidae (3), and Leptoceridae (14). Polycentropus kingi McLachlan, 1881; Agrypnia picta Kolenati, 1848; Limnephilus sericeus (Say, 1824); L. dispar McLachlan, 1875; L. elegans Curtis, 1834, and Hagenella clathrata (Kolenati, 1848) are rare in Europe. Some of the revealed species are critically endangered in several countries of western Europe. The studied protected areas play an important role in conservation of species diversity and in the distribution of several rare species.  相似文献   

5.
The insecticide load in surface waters does not ordinarily reach concentrations acutely toxic to aquatic fauna. The effects of the low insecticide concentrations typical of natural habitats are still not clear, for they often appear only after relatively long exposure times. To test such a situation, the insecticides lindane and parathion were introduced into a static-with-renewal outdoor aquaria system at concentrations about four and five orders of magnitude lower than their respective 96-h LC50s, and their chronic (about 90 days) effects on the survival rate of freshwater caddisfly larvae were observed. The emergence and hence survival rate of Limnephilus lunatus Curtis was significantly reduced by lindane at 0.1 ng l–1, a value nearly five orders of magnitude lower than the 96-h LC50. Parathion, with acute and subacute toxicity similar to that of lindane, did not significantly alter the emergence rate of this species. In contrast, this substance did produce a significant reduction in emergence rate of the closely related species Limnephilus bipunctatus Curtis at 1 ng l–1, even though this species was significantly less susceptible than L. lunatus to parathion at high concentrations. We conclude that chronic insecticide exposure can be hazardous to freshwater macroinvertebrates even at unexpectedly low concentrations. The low-concentration effects may depend on both species and substance and therefore cannot be predicted from toxicity data at higher concentrations.  相似文献   

6.
The identification of British limnephilid larvae (Trichoptera)   总被引:2,自引:0,他引:2  
Fifty–six species of Limnephilidae have been recorded from Britain. Larvae of forty–three species were collected, and the identities of forty–two were confirmed by direct association of individual larvae with their resultant adult stage. Information was obtained on the larvae of twelve more species, leaving the larva of only onespecies, Limnephilus fuscinervis, unknown. A key is provided to the fifth instar larvae of fifty–four species. Limnephilus nigriceps is omitted from the keydue to lack of information. The terminology of morphological characters is reviewed.  相似文献   

7.
In the present study a new species of the genus Anabolia, A. anatolica sp. n. from the Taurus Mountains in southern Anatolia is described and illustrated. The new species is related to A. laevis Zetterstedt, 1840 from northern Europe and is a glacial relict species of Pleistocene origin.  相似文献   

8.
Larvae of the caddisfly Limnephilus lunatus Curtis were exposed to the pyrethroid fenvalerate for one hour and transferred to artificial outdoor stream systems, where their survival rate and emergence were monitored over 84 days. Lethal effects of the pyrethroid almost always appeared shortly after the short-term contamination, but chronic influences were also observed. At a concentration of only 0.01 µg l–1 a slight increase in mortality over the entire period of observation, as well as a delay in development and hence in emergence occurred. Such reactions under field conditions may impair the survival of this species, and sublethal effects of brief pyrethroid contamination, previously largely ignored, can have important consequences for aquatic macroinvertebrates.  相似文献   

9.
The last instar larva and the pupa of Ptilocolepus extensus McLachlan, 1884, an endemic of the Iberian Peninsula, are described for the first time. The final instar larva of Pt. extensus bears close resemblance to those of Ptilocolepus granulatus (Pictet, 1834), but the abdomen has a well-developed dorsal sclerotized plate on segment VIII; this is a morphological feature which has not been observed in any other Ptilocolepinae. Final instar larvae make dorsoventrally flattened, elongate-oval cases of leaf pieces from several moss and liverwort species; such cases are characteristic of the Ptilocolepinae. Some additional data on biology and geographical distribution are given.  相似文献   

10.
A molecular taxonomic study on the north European species of the genus Agathomyia Verrall (Diptera: Platypezidae) is presented. We include molecular phylogenetic analyses based on two fragments of the mtDNA COI and a fragment of the nuclear 28S rDNA genes for both adult and immature stages of Agathomyia spp. The Agathomyia elegantula (Zetterstedt) group taxa were revised based on the newly obtained molecular and morphological data. Two new species belonging to the A. elegantula group were described, Agathomyia alneti Ståhls & Rättel sp.n. and A. shatalkini Ståhls sp.n. Agathomyia boreella (Zetterstedt) and A. scutellaris (Zetterstedt) were resurrected from synonymy of A. elegantula Zetterstedt. The genus Antrodiella Ryvarden & I.Johans was recorded as fungal host for Agathomyia elegantula group species and is a new host fungus genus for Platypezidae and for genus Agathomyia. Antrodiella faginea and A. pallescens were recorded as host fungi for A. boreella, A. pallescens for A. elegantula and A. serpula for A. alneti sp.n. We present identification keys to males and to all hitherto known third‐stage larvae of north European Agathomyia species including digital images, and discuss conservation aspects for these taxa.  相似文献   

11.
In laboratory experiments with full-grown larvae of three Trichoptera species (Limnephilus rhombicus, Potamophylax rotundipennis and Sericostoma pedemontanum) in an artificial stream, four types of bottom material were provided in combination with various currents. Only L. rhombicus reacted to low current speed (9 cm/sec), moving downstream when a bottom current was present. L. rhombicus and P. rotundipennis showed a distinct preference for pebbles over sand and for coarse pebbles over crushed brick. S. pedemontanum burrowed under pebbles or stones. L. rhombicus showed a distinct tendency to climb onto the dividing gauze or vertical sticks. All three species preferred shaded parts of the experimental stream to the illuminated parts. The results are related to field observations. Limnephilus rhombicus occurs in stagnant and slow-running waters. Potamophylax rotundipennis is restricted to rather fast-running streams with a perpetual flow, while Sericostoma pedemontanum occurs in the same type of stream.  相似文献   

12.
The predacious behaviour of Dytiscus circumcinctus and D. latissimus larvae was studied experimentally. When offered different prey simultaneously, D. latissimus larvae preferred cased caddis larvae relative to mayfly nymphs and isopods, whereas in D. circumcinctus the preference order was reversed. Notonectid nymphs and tadpoles were consumed in higher numbers by D. circumcinctus than by D. latissimus larvae. D. circumcinctus larvae and instar III larvae of D. latissimus most frequently captured caddis larvae through the case wall, whereas the instar I and II larvae of D. latissimus normally attacked the thorax of the exposed larva from above the front opening of the case. Limnephilus borealis, L. nigriceps and L. rhombicus caddis larvae differed in case structure, and they were all successfully captured by D. latissimus and D. circumcinctus instar II and III larvae. Neither capture success nor ingestion efficiency varied significantly between the two Dytiscus species or between different prey species. Instar II and III D. circumcinctus larvae had shorter reaction times than those of D. latissimus. The larger L. borealis and L. rhombicus larvae were preferred by the two last Dytiscus larval instars, and the handling time of these two prey was longer than that of L. nigriceps larvae.  相似文献   

13.
Camponotus femoratus is an abundant and behaviorally dominant ant in lowland Amazonian rainforests, where this species participates in a complex and obligate seed-dispersal mutualism. C. femoratus typically cohabits with another ant species Crematogaster levior in an apparently amiable but poorly understood interaction. Despite these outstanding characteristics, the population genetics and dispersal patterns of C. femoratus are unknown. We isolated eight polymorphic microsatellite loci for C. femoratus from a genomic library enriched for di-, tri-, and tetra-nucleotide repeats. We detected 2 to 17 alleles per locus, with levels of observed heterozygosity ranging from 0.286 to 0.714.  相似文献   

14.
Brown trout (Salmo trutta L.) and sculpin (Cottus gobio L.) predation on the cased limnephilid larvae Glyphotaelius pellucidus (Retz.) (weak, broad leaf case), Limnephilus pantodapus McLachl. (weak, long cylindrical leaf case), L. rhombicus (L.) (rigid, hedgehog case) and Potamophylax cingulatus (Steph.) (rigid, cylindrical mineral case) was studied in the laboratory. The proportion of larvae ingested was significantly higher in brown trout than in sculpin for all four prey species. Brown trout captured larvae of all four species with equal success, but the higher number of unsuccessful captures resulted in a higher survival rate for P. cingulatus. It was significantly more difficult for sculpin than for brown trout to capture L. pantodapus larvae and to ingest all species except L. rhombicus. P. cingulatus larvae were never ingested by sculpins, and had the highest survival rate after capture by both fish species. In brown trout, the handling time of L. pantodapus was significantly longer than that of P. cingulatus. Sculpin had a significantly longer handling time of G. pellucidus than brown trout. L. pantodapus and L. rhombicus larvae feigned dead significantly longer than did those of G. pellucidus and P. cingulatus upon attacks from sculpins. L. rhombicus larvae also feigned dead for a long time upon attacks from brown trout. The survival rate of a larva attacked by sculpin or brown trout depends on both case rigidity as well as its behaviour. Brown trout was a more successful predator of cased caddis larvae than sculpin.  相似文献   

15.
1. The occurrence of larvae of Limnephilus coenosus and L. vittatus (Trichoptera) was recorded in 103 rock pools both before and after the dry periods in spring–summer (April–May and July–early August), when a great number of the pools dried out. In early spring, 84% of the pools sampled contained larvae of at least one of the species. Limnephilus coenosus larvae were present in a higher proportion of pools that later dried out than in the permanent ones, while L. vittatus larvae were predominantly found in permanent pools. Larvae of both species were found together in 31% of the inhabited pools.
2. Laboratory experiments, designed to elucidate differential survival under drought conditions, demonstrated that the organic cases of L. coenosus larvae held water more efficiently than did the mineral L. vittatus cases. Full-grown (fifth instar) L. coenosus larvae also survived dry conditions better than did L. vittatus larvae. The higher survival of L. coenosus was due to a combination of drought-resistant case material and a higher survival ability of the larvae themselves.
3. Limnephilus vittatus larvae were restricted by their low capability to withstand desiccation, although case material and food were available for L. vittatus larvae in all pools. Absence of case material and high-quality food in many pools, however, restricted the presence of L. coenosus larvae, but this species did not suffer from heavy mortality because of desiccation and all pool populations of L. coenosus survived until pupation.
4. The differences in species composition in these temporary and permanent pools can be explained by the differential site selection by ovipositing females, as well as by larval survival. The intrinsically greater survival of L. coenosus larvae during drought, together with the water-retaining properties of the cases, allowed this species to exploit stressful and risky habitats, such as temporary pools.  相似文献   

16.
1. The occurrence of larvae of Limnephilus coenosus and L. vittatus (Trichoptera) was recorded in 103 rock pools both before and after the dry periods in spring–summer (April–May and July–early August), when a great number of the pools dried out. In early spring, 84% of the pools sampled contained larvae of at least one of the species. Limnephilus coenosus larvae were present in a higher proportion of pools that later dried out than in the permanent ones, while L. vittatus larvae were predominantly found in permanent pools. Larvae of both species were found together in 31% of the inhabited pools.
2. Laboratory experiments, designed to elucidate differential survival under drought conditions, demonstrated that the organic cases of L. coenosus larvae held water more efficiently than did the mineral L. vittatus cases. Full-grown (fifth instar) L. coenosus larvae also survived dry conditions better than did L. vittatus larvae. The higher survival of L. coenosus was due to a combination of drought-resistant case material and a higher survival ability of the larvae themselves.
3. Limnephilus vittatus larvae were restricted by their low capability to withstand desiccation, although case material and food were available for L. vittatus larvae in all pools. Absence of case material and high-quality food in many pools, however, restricted the presence of L. coenosus larvae, but this species did not suffer from heavy mortality because of desiccation and all pool populations of L. coenosus survived until pupation.
4. The differences in species composition in these temporary and permanent pools can be explained by the differential site selection by ovipositing females, as well as by larval survival. The intrinsically greater survival of L. coenosus larvae during drought, together with the water-retaining properties of the cases, allowed this species to exploit stressful and risky habitats, such as temporary pools.  相似文献   

17.
A total of 75 species of leafrollers of the family Tortricidae belonging to 41 genera were found in northern and Inner Anatolia between 1999 and 2003. Cochylidia moguntiana (Rössler, 1864) is newly recorded for Turkey, and the first detailed records of Aphelia viburniana (Fabricius, 1787), Epiblema turbidana (Treitschke, 1835), Eucosma conterminana (Guenée, 1845) and Cochylidia rupicola (Curtis,1834) are communicated.  相似文献   

18.
Albert Lillehammer 《Ecography》1978,1(2-3):255-260
Trichopteran larvae were sampled on soft substrata at all depths, on stony substrata in the exposed zone, and the adults in emergence traps, placed along the lake shore. Fourteen species were taken as larvae in the lake. On stony substrata and in the exposed zone Polycentropus flavomaculatus (Pictet) was dominant, followed by Limnephilus nigriceps (Zetterstedt) in terms of numbers. In terms of biomass L. nigriceps dominated followed by Potamophylax cingulatus (Stephens).
Species which usually inhabit running water made up for a larger part of the trichopteran fauna of the exposed zone.
The two most numerous species showed different habit preferences. P. flavomaculatus was most common on stable stony bottom, while L. nigriceps was most common on unstable stony bottom. The other species showed no significant preference. On unstable soft bottom at 3 m and below, Mystacides azureus (L.) dominated, accounting for about 90% of the total trichopteran fauna both in terms of weight and numbers.
The major trichopteran species in the lake were either detritus feeders, such as M. azureus, L. nigriceps and Potamophylax spp. or omnivores such as P. flavomaculatus and Molanna albicans (Zetterstedt).  相似文献   

19.
20.
SUMMARY. The oxygen uptake of Limnephilus rhombicus , a typical inhabitant of lentic waters, was measured in three different experimental situations: in still water with a plastic mesh as a substrate, in stirred water with a plastic mesh and in still water without any substrate. Water flow caused a small increase in oxygen uptake at all temperatures but principally above 15°C. The presence or absence of the plastic substrate had little influence on oxygen uptake; L. rhombicus can be active over the whole range of temperatures studied but its activity is always small. Its metabolism—temperature curve stands out in having a plateau between 5 and 10°C, with a steeper part between 10 and 20°C, the slope of which varies according to the conditions. Maximum oxygen uptake at high temperatures was relatively low (1235 ± 153 μl O2g dry wt-1h-1 at 25°C).
The results are compared with those obtained previously for the larvae of Microptema testacea which inhabit flowing zones in brooks. L. rhombicus larvae appear both as cold-water animals and as animals from highly variable biotopes. They are in fact very ubiquitous and occupy all lentic biotopes from cold and mountainous districts to temperate lowlands.  相似文献   

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