Journal of Comparative Physiology B

, Volume 179, Issue 7, pp 897–902 | Cite as

Simultaneous freeze tolerance and avoidance in individual fungus gnats, Exechia nugatoria

  • Todd Sformo
  • F. Kohl
  • J. McIntyre
  • P. Kerr
  • J. G. Duman
  • B. M. Barnes
Original Paper


Freeze tolerance and freeze avoidance are typically described as mutually exclusive strategies for overwintering in animals. Here we show an insect species that combines both strategies. Individual fungus gnats, collected in Fairbanks, Alaska, display two freezing events when experimentally cooled and different rates of survival after each event (mean ± SEM: −31.5 ± 0.2°C, 70% survival and −50.7 ± 0.4°C, 0% survival). To determine which body compartments froze at each event, we dissected the abdomen from the head/thorax and cooled each part separately. There was a significant difference between temperature levels of abdominal freezing (−30.1 ± 1.1°C) and head/thorax freezing (−48.7 ± 1.3°C). We suggest that freezing is initially restricted to one body compartment by regional dehydration in the head/thorax that prevents inoculative freezing between the freeze-tolerant abdomen (71.0 ± 0.8% water) and the supercooled, freeze-sensitive head/thorax (46.6 ± 0.8% water).


Mycetophilidae Exechia nugatoria Supercooling Exotherm 



Supercooling point 1


Supercooling point 2


Relative humidity


Water content



This study was supported by National Science Foundation grants IOB06-18436 to BMB and IOB06-18342 to JGD. We wish to thank B. Tudor, K. Walters (Notre Dame), D. Wagner (UAF) for use of scales, G. Juday (UAF) and R. Lee (Miami University, Ohio) for critical discussions, and D. Sikes (UAF Museum) for initial insect identification.


  1. Becwar MR, Rajashekar C, Hansen-Bristow KJ, Burke MJ (1981) Deep supercooling of tissue water and winter hardiness limitations in timberline flora. Plant Physiol 68:111–114PubMedCrossRefGoogle Scholar
  2. Bennett VA, Sformo T, Walters K, Toien Ø, Jeannet K, Hochstrasser R, Pan Q, Serianni AS, Barnes BM, Duman JG (2005) Comparative overwintering physiology of Alaska and Indiana populations of the beetle Cucujus clavipes (Fabricius): roles of antifreeze proteins, polyols, dehydration and diapause. J Exp Biol 208:4467–4477PubMedCrossRefGoogle Scholar
  3. Bigg EK (1953) The supercooling of water. Proc Phys Soc London B66:688–694Google Scholar
  4. Cary JW (1985) Freeze survival in peach and prune flowers. Plant Sci Lett 37:265–271CrossRefGoogle Scholar
  5. Collins SD, Allenspach AL, Lee RE (1997) Ultrastructural effects of lethal freezing on brain, muscle and Malpighian tubules from freeze-tolerant larvae of the gall fly, Eurosta solidaginis. J Insect Physio 43:39–45CrossRefGoogle Scholar
  6. Duman JG (2001) Antifreeze and ice nucleator proteins in terrestrial arthropods. Ann Rev Physio 63:327–357CrossRefGoogle Scholar
  7. Elnitsky MA, Benoit JB, Lee RE, Denlinger DL (2008) Desiccation tolerance and drought acclimation in the Antarctic collembolan Cryptopygus antarcticus. J Insect Physiology 54:1432–1439CrossRefGoogle Scholar
  8. George MF, Burke MJ, Pellet HM, Johnson AG (1974) Low temperature exotherms and woody plant distributions. HortScience 9:519–522Google Scholar
  9. Hadley NF (1994) Water relations of terrestrial arthropods. Academic Press, New YorkGoogle Scholar
  10. Hedmark K (2000) Svampmyggor i taigan—nya arter för Sverige i ett fennoskandiskt perspectiv (Diptera: Siaroidea exkl Sciaridae). Entomologisk Tidskrift 121:73–89Google Scholar
  11. Jaklovlev J, Siitonen J (2004) Finnish fungus gnats (Diptera Mycetophilidae etc.): faunistics, habitat requirements and threat status. Lammi Notes 30:3–7Google Scholar
  12. Johannsen OA (1912) The Mycetophilidae of North America. Part IV. Maine Agric Exp Station Bull 200:57–146Google Scholar
  13. Katsuga J, Hashidko Y, Nishioka A, Yoshiba M, Arakawa K, Fujikawa S (2008) Deep supercooling xylem parenchyma cells of katsura tree (Cercidiphyllum japonicum) contain flavonol glycosides exhibiting high anti-ice nucleation activity. Plant Cell Environ 31:1335–1348CrossRefGoogle Scholar
  14. Kjaerandsen J (1993) Diptera in mines and other cave systems in southern Norway. Entomologica Fennica 4:151–160Google Scholar
  15. Kurina O (1996) Hibernation of fungus gnats (Diptera: Mycetophilidae) in Estonian caves. Studia Dipterologica 3:221–229Google Scholar
  16. Lundheim R, Zachariassen KE (1993) Water balance of over-wintering beetles in relation to strategies for cold tolerance. J Comp Physiol B 163:1–4CrossRefGoogle Scholar
  17. Miller LK (1978) Physiological studies of arctic animals. Comp Biochem Physio 59A:327–334CrossRefGoogle Scholar
  18. Miller K (1982) Cold hardiness strategies of some adult and immature insects overwintering in interior Alaska. Comp Biochem and Physio 73A:595–604CrossRefGoogle Scholar
  19. Quamme HA (1995) Deep supercooling in buds of woody plants. In: Lee RE, Warren GJ, Gusta LV (eds) Biological ice nucleation and its applications. American Phytopathological Society Press, St. Paul, pp 183–199Google Scholar
  20. Quamme HA, Stushnoff C, Weiser CJ (1972) The relationship of exotherms to cold injury in apple stem tissues. J Amer Soc Hort Sci 97:608–613Google Scholar
  21. Sakai A (1979) Freeze avoidance mechanism of the primordial shoots of conifer buds. Plant Cell Physiol 20:1381–1390Google Scholar
  22. Storey KB, Storey JM (1991) Biochemistry of cryoprotectants. In: Denlinger D, Lee RE (eds) Insects at low temperature. Chapman and Hall, New York, pp 64–93Google Scholar
  23. Väïsänen R (1981) Umbelliferous stems as overwintering sites for Mycetophilidae (Diptera) and other invertebrates. Notulae Entomologicae 61:165–170Google Scholar
  24. Wisniewski M (1995) Deep supercooling in woody plants and the roles of cell wall structure. In: Lee RE, Warren GJ, Gusta LV (eds) Biological ice nucleation and its applications. American Phytopathological Society Press, St. Paul, pp 163–181Google Scholar
  25. Yi S-X, Lee RE (2003) Detecting freeze injury and seasonal cold-hardening of cells and tissues in the gall fly larvae, Eurosta solidaginis (Diptera: Tephritidae) using fluorescent vital dyes. J Insect Physio 49:999–1004CrossRefGoogle Scholar
  26. Zachariassen KE (1985) Physiology of cold tolerance in insects. Physiol Rev 65:799–832PubMedGoogle Scholar
  27. Zachariassen KE, Perersen SA, Kristiansen E (2004) Advantages and disadvantages of freeze-tolerance and freeze-avoidance overwintering strategies. In: Barnes BM, Carey HV (eds) Life in the cold: evolution mechanisms adaptation, and application. Institute of Arctic Biology, Fairbanks, pp 283–291Google Scholar
  28. Zachariassen KE, Li NG, Laugsand AE, Kristiansen E, Pedersen SA (2008) Is the strategy for cold hardiness in insects determined by their water balance? A study on two closely related families of beetles: Cerambycidae and Chrysomelidae. J Comp Physiol B 178:977–984PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Todd Sformo
    • 1
  • F. Kohl
    • 1
  • J. McIntyre
    • 2
  • P. Kerr
    • 3
  • J. G. Duman
    • 4
  • B. M. Barnes
    • 1
  1. 1.Institute of Arctic BiologyUniversity of Alaska FairbanksFairbanksUSA
  2. 2.Department of Mathematics and StatisticsUniversity of Alaska FairbanksFairbanksUSA
  3. 3.Plant Pest Diagnostics Branch, California State Collection of ArthropodsCalifornia Department of Food and AgricultureSacramentoUSA
  4. 4.Department of Biological SciencesUniversity of Notre DameNotre DameINUSA

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