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Talbe IV. Oxygen consumption given in mligihr at 5O, lo0, 15' and 20' C for some active specimens of different invertebrate species Species 5" C lo0 C 15' C 20° C Nebria gyllenhali N. niualis Patrobus septentrionis Calathus melanocephalus Anzara alpina Otiorrhynchus dubius Melasoma collaris, larva M. collaris imago Zygaena exulans $ Z. exulans 9 were not taken into consideration during the sampling of the material presented here. The high caloric content in eggs of 2. exulans indicates a high fat content. The ash content is lower than that found in bird species (Ricklefs 1967, Myrcha & Pinowski 1969, Skar et al. 1972). This difference is probably caused by the presence of bone tissue and feathers in birds. The order of magnitude of the ash content in the present material corresponds to earlier studies among invertebrates (Wiegert 1965, Klekowski et al. 1967, Hofsvana 1973). u Al1 the coleopterous species investigated (imagines) showed a clear decline in the \ u , water percentage with increasing dry weight. According to Szwykowska (1969), Skar (1969), and Skar et al. (1972), a correlation exists between a hiah fat content and a low water u percentage in animal tissue. It must be anticipated that the increase in dry weight of adult Coleoptera is correlated with an increased percentage of fat, relatively little new water being added. Correspondingly, Klekowski et al. (1967) found that in the last larva1 instars of 'Tribolium castaneum (Hbst.), an increase in caloric content was correlated with a decrease in water percentage. As shown in Fig. 10, the marked decline in water percentage when dry weight increases results in a decre'asing water weight when the dry weight exceeds a certain value. In larvae and pupae of 2. exulans, however, the decline in water percentage is so small that a similar effect is not achieved. Imagines of 2. exulans showed a very stable water percentage even though the dry weight varied markedly. This is probably explained by the fact that the body weight of this species does not increase after hatching, and no fat reserves are built up. On the contrary, the body weight of both males and females decreases markedly after hatching. Evidently the animals only ingest small amounts of food (probably nectar), keeping the water percentage constant and keeping the body weight above a certain value. These conditions are easily explained by the life cycle, the population hatching almost simultaneously on warm days, swarming, copulating, and laying new eggs within a few days. There is no need for this species to build up a fat reserve, contrary to coleopterous species which depend on a certain amount of activity to allow the sexes to meet, and probably also to develop their reproductive organs. Furthermore, many coleopterous species hibernate as adults and need to build up a fat reserve before hibernation. The very small reduction in water percentage among larvae of 2. exulans when dry weight increases indicates that the fat content does not increase much during the larva1 development. This is verified through the caloric values for larvae of different dry weight groups (Table TI). There is a slight increase in caloric content when dry weight increases, but the difference is significant only between the first and third group (t-test. 0.95
Terrestrial arthrofiods from Finse 125 summer season. According to Tullgren et al. (1911), it is possible that Z. exulans has a two-year life cycle. This would imply one or two hibernations for the larvae, perhaps including an accumulation of fat before winter. It is reasonable that pupae should also show a slight decrease in water percentage with increasing dry weight, representing fully developed larvae of different weights. However, after hatching, the water percentage becomes remarkably stable for different weight groups. There is no clear difference between the sexes - the males perhaps have slightly lower values. The oxygen consumption increases markedly from 5' to 20°C, in most cases following a slightly exponential trend. The variation within each temperature may be considerable for a given species. This is mainly probably caused by differences in the physiological state of animals. as onlv animals which are motionless or show very little movement during the experiment were used for calculations of the mean values. The listing of values for clearly active animals shows that respiration may increase manyfold during activity. In N. niualis, very active animals at 5 ' ~ might have an oxyben consumption almost five times higher than animals at rest. This fact shows that when calculating the oxygen consumption of an individual during natural conditions, both temperature variations in the habitat, the length of each developmental stage, and the activity pattern of the animal must be taken into consideration. The mean values recorded for resting animals at different temperatures correspond mainly with earlier data from arctic arthropods (e.g. Scholander et al. 1953). In a study on the aerobic and anaerobic metabolism of the carabid beetle Pelofihila borealis Payk. at Finse, Conradi-Larsen & Ssmme (1973) found a respiration rate in summer that was similar to the values we have recorded for A. alfina. In an earlier work, 0stbye (1963) recorded twice as high respiration rates for N. niualis as found in this study. The rates for N. gyllenhali in his study were similar to those recorded here, except for those at a temperature of 10°C, where he found the values doubled. Both beetles in his study showed the same pattern of oxygen uptake with little or no increase in consumption rate in the temperature range between 10' and 20°C. Their optima of temperature preference were found to be within the same temperature range, thus indicating a stabilizing mechanism for metabolism in this range. Schmidt (1956) observed corresponding regulation levels in oxygen uptake in experiments on transpiration, oxygen consumption, and prefetred temperatures in some Carabus species. These regulation levels, however, were relatively small. In the present study, such regulation levels may have been overlooked, because of too large intervals between the temperatures at which the respiration rates were measured. Respiration data from eggs, pupae, larvae and imagines in M. collaris and Z. exulans show that the oxygen consumption per gram and hour may vary markedly during development. In both species eggs have the lowest respiration rate at al1 temperatures. The two species differ much concerning the oxygen consumption of larvae. The mean value for M. collaris larvae at 5OC is higher than the mean value of Z. exulans larvae at 15OC. At al1 temperatures, larvae of the former species have a respiration about four times higher than the latter. This difference can be explained by the difference in life cycle. The larvae of M. collaris grow very fast and have a larva1 period of about 12 days at 20' C. Larvae of 2. exulans kept in culture at the same temperature changed their weight very little during 10 days. The loss of weight during ecdysis seemed to be considerable, and observations indicate that the larvae do not eat for severa1 days during ecdysis, contrary to larvae of M. collaris. In Z. exulans the larva1 period makes up the greatest part of the life cycle, which, as mentioned earlier, perhaps lasts for two years. In M. collaris the imagina1 stage covers the main period of the life cycle, there is a new generation every year, and the larva1 period lasts only a few weeks. The respiration of pupae is clearly lower than for imagines of M. collaris. In Z. exulans the pupal respiration is similar to that of larvae and females. Males have a somewhat higher respiration, probably making them better suited for swarming activity. The values are similar to those of adult M. collaris. In this species no distinction was made
Page 2 and 3: Norsk Entorriologisk Tidsskrift Nor
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Page 6 and 7: Dry Weight , mg. Fig. 7. Correlatio
Page 8 and 9: Table 11. Caloric values per g dry
Page 12 and 13: etween the sexes during the respira
Page 14 and 15: 128 A. Fjellberg Fig. 2. A. sefiten
Page 16 and 17: 130 A. Fjellberg HABITATS Until now
Page 18 and 19: 132 L. Semme the autumn. The prelim
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Page 22 and 23: 136 J. E. Brittain Fig. 1. The loca
Page 24 and 25: 138 J. E. Brittain period was longe
Page 26 and 27: 140 J. E. Brittain Table 11. Ph~sic
Page 28 and 29: 142 J. E. Brittain Table IV. Physic
Page 30 and 31: 144 J. E. Brittain EPHEMEROPTERA Am
Page 32 and 33: 146 J. E. Brittain 0-3 NYMPHS I I 1
Page 34 and 35: 148 J. E. Brittain 1-3 NYMPHS 01 I
Page 36 and 37: 150 J. E. Brittain Nemzlrella picte
Page 38 and 39: 152 J. E. Brittain ture and the inc
Page 40 and 41: (Nord-Norwegen) (Trichoptera, Pleco
Page 42 and 43: from anoxia. Drops of haemolymph we
Page 45 and 46: Notes on little known spiders in No
Page 47 and 48: Symphyla and Pauropoda from two con
Page 49 and 50: Symphyla and Pauropoda 163 Table 11
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Page 59 and 60: Abundance and diversity in the faun
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Nocturnal moths 175 Table 1. Number
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Nocturnal moths 177 Grimstad Amli 1
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Nocturnal moths 179 Am/i. Norway 19
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Nocturnal moths 181 Grimstad, Norwa
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Nocturnal moths 183 %60 50 40 30 20
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Spinosellina forms of Sminthurides
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A constant pressure microrespiromet
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Microrespirometer 189 termination o
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192 F. E. Klallsen The specimens fr
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194 F. E. Klausen REFERENCES Ardii,
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196 A. Lillehammer present in Norwa
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198 A. Lillehammer Results The numb
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200 A. Lillehammer Fennoscandian co
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202 A. Lillehammer parts of the are
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204 A. Lillehammer carnivorous spec
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Table IV. Species distribution, in
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Table V. Species distribution in se
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210 A. Lillehammer The bottom of th
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212 A. Lillehammer Blatjemn Diura b
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Table VII. Species distribution in
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Z 0 ...... ~ '"s' '" ~ .... '.xl ~
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Table IX. Species distribution in s
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220 A. Lillehammer same latitude as
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222 A. Lillehammer Table XI. The pH
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224 A. Lillehammer These species se
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226 A. Lillehammer Table XVI. The s
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228 A. Lillehammer Fig. 22. Stream
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230 A. Lillehammer Fig. 25. Distrib
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238 A. Lillehammer high altitude la
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244 A. Lillehammer streams and rive
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246 A. Lillehammer Blies (1953, 195
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248 A. Lillehammer streams are to a
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250 A. Lillehammer Muller, K. 1955.
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252 Bokanmeldelser produserende, en
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N orsk Entomologisk Tidsskrift Norw
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