Critical thermal maximum and body water loss in first instar larvae of three Cetoniidae species (Coleoptera)

Critical thermal maximum (CTmax) and body water losses were measured in first instar larvae of Gnorimus nobilis, Osmoderma eremita (Trichiinae) and Cetonischema aeruginosa (Cetoniinae) when air temperature was increased gradually (0.5 degrees C/min) from 20 degrees C to the critical thermal maximum (CTmax), in dry air (near 0% R.H.). The CTmax was significantly lower in O. eremita (45.6 +/- 0.7 degrees C) than in G. nobilis (48.5 +/- 0.6) and C aeruginosa (51.4 +/- 0.9 degrees C). An increase of 10 degrees C (30-40 degrees C) induced a 2-fold increase of the water loss in C aeruginosa and O. eremita (Q(10) = 2.10 + 0.12 and 2.13 + 0.20, respectively). In the range from 40 to 45 degrees C to CTmax a strong increase of the water loss was observed in O. eremita and C. aeruginosa, respectively. Body water losses were significantly lower in C aeruginosa than in O. eremita and G. nobilis over the range 20 degrees C-CTmax; no significant difference occurred between G. nobilis and O. eremita. (c) 2005 Elsevier Ltd. All rights reserved.