Respiration during the metamorphosis of sexuals in Lasius flavus (Hymenoptera, Formicidae)

ABSTRACT. The respiration of metamorphosing gyne Lasiusflavus Fab. has been measured in field and laboratory populations. Twelve morphological stages are identified and their respiratory rate investigated. Only five physiological phases are distinguished. The specific respiratory rate varies between these phases, to produce the U-shape characteristic of insects. There is good agreement between the data from English field and Danish laboratory populations. The minimum rate is only 40% of the maximum. Except at the beginning and end of metamorphosis, the Q₁₀ is significantly different in the two temperature intervals 10–20 and 20–30C. Metamorphosis was completed in approximately 33 days at 20C. The total oxygen consumption by the gynes during metamorphosis was 2.4 ml. Their weight loss amounted to 2.2 mg, or 36% of the dry weight and, of this, 0.67mg was accounted for by fat. Assuming the rest was carbohydrate, consumption of these reserves would release 62.9 J, which, for this combination of fat and carbohydrate, can be calculated to be equivalent to 3.1 ml oxygen which is in reasonable agreement with the figure calculated from the measurement of oxygen consumption. The specific respiratory rate in English field populations of male pupae varies in the same way as the gyne-pupae, but it is about 50% higher.