Abstract: 【Aim】 This study aims to explore the role of secondary reproductives in the colony stabilization and development in Reticulitermes labralis. 【Methods】 In the present study, we investigated the field termite colonies, established and compared paired female-male swarming colonies with isolated secondary reproductive colonies during the initial stage of colony foundation.【Results】 A pair of primary king and queen and a large number of secondary reproductives were found in collected field colonies. Three types of secondary reproductives were observed in R. labralis, i.e., apterous neotenics moulted from workers, brachypterous neotenics moulted from nymphs and adultoid reproductives moulted from the last-instar nymphs. The survival rates of paired colonies and isolated colonies under laboratory conditions in the 1st month were 64% and 96%, respectively. The number of individuals in paired colonies increased slowly with time. The mean numbers of individuals in paired colonies in the 2nd and 10th months were 6.3±1.54 and 8.4±1.47, respectively, while those in isolated colonies were 52.4±6.44 and 164.3±20.85, respectively. The secondary queens in field colonies had huge ovaries like the primary queens. 【Conclusion】 The secondary reproductives of R. labralis were not only the main reproductive individuals in termite colonies, but also the most important reproductive caste for colonies foundation.

Key words: Reticulitermes labralis, termite, secondary reproductive, isolated colonies, colony dispersal, reproductive capacity