On the reproductive strategies post-colony foundation: major termite pest species with distinct ecological habits differ in their oviposition dynamics.

Termite colony foundation precedes the incipient stage, when the first oviposition cycle takes place, followed by months of reproductive inactivity. The royal couple is supposed to cease oviposition during this period, investing energy to care for the first brood. When a suitable number of alloparents differentiate, egg-laying resumes. Here we followed oviposition dynamics, embryo development and queen/king body changes in laboratory colonies of the major pest species Coptotermes gestroi (Rhinotermitidae) and Cryptotermes brevis (Kalotermitidae) during 9 months. We show that they differ in these oviposition dynamics, as C. gestroi queens displayed an uninterrupted oviposition whereas C. brevis laid a cohort of eggs and ceased oviposition during a 3-month period (lag phase). C. gestroi oviposition dynamic was remarkable and suggests that occurrence of progeny was not a limiting factor, thus queens and kings were able to concomitantly invest energy in reproduction and parental care. These findings contrast those reported for rhinotermitids from temperate areas, and we discuss the likely reasons for such a condition, including endogenous rhythms, avoidance of a high mortality rate of the first progeny and adaptation to the weather conditions of the Neotropical region. Oviposition dynamic in C. brevis resembled those of several termite species, in which the royal couple cease reproduction to care for the first brood. Rearing conditions did not influence oviposition dynamics (egg-laying cycle followed by a lag phase), thus our results on the oviposition of C. gestroi and C. brevis correspond to different reproductive strategies post-foundation adopted by these pest species.

Workers' Extra-Nest Behavioral Changes During Colony Fission in Dinoponera quadriceps (Santschi).

Ant colonies can reproduce by two strategies: independent foundation, wherein the queen starts a new colony alone, and dependent foundation, in which workers assist the queen. In the queenless species Dinoponera quadriceps (Santschi), the colony reproduces obligatorily by fission, a type of dependent foundation, but this process is not well understood. This study describes a colony fission event of D. quadriceps in the field and analyzes the influence of the fission process on workers' extra-nest behavior. Based on observations of workers outside the nest, five distinct stages were identified: monodomic stage, polydomic stage, split stage, conflict stage, and post-conflict stage. The colony was initially monodomic and then occupied a second nest before it split into two independent colonies, indicating a gradual and opportunistic dependent foundation. After the fission event, the daughter colony had aggressive conflicts with the parental colony, resulting in the latter's disappearance. Colony fission affected workers' extra-nest behavior by increasing the frequency of rubbing the gaster against the substrate (which probably has a chemical marking function) and by decreasing the frequency of foraging during the split stage. After the fission event, the number of foragers was halved and foragers remained nearer to the nest during extra-nest activity. The spatial closeness of the parental and daughter colonies led to competition that caused the extinction or migration of the parental colony. Intraspecific competition was indicated by foraging directionality at the colony level, whereby areas of neighbor colonies were avoided; this directionality was stronger while both colonies coexisted.