Zur Biologie von Trogoderma variabile Ball. (Col. Dermestidae): Larvalentwicklung und Larvaldiapause

Larval development ofT. variabile under various environmental conditions is examined to estimate the potential damages in storehouses in Central Europe. Larvae develop between 21 and 37°C, lower temperatures considerably prolong the time of development: at 25° it lasts 48.3 days (♂ ♂) and 60.8 days (♀ ♀), at 30° 29.3 days (32.9 resp.), and at 35° 27.5 days (34.6 resp.). Female larvae on an average pupate after six larval instars, males after five. From this results the earlier pupation of the males. Isolated larvae do not pupate; they grow up to big and resistant dauerlarvae and possibly pass through a diapause of several years. Reared in groups larvae pupate promptly and diapause is terminated. Longevity, cold resistance and ability of starvation of dauerlarvae are examined. The results indicate that a development ofT. variabile in unheated rooms is possible. Because of the very slow development at lower temperatures economic important damages are unlikely.