Rhagoletis conversa (Brethes, 1919)

Frías-Lasserre, Daniel, S, Andrea Luna & Villagra, Cristian A., 2019, Differences in larval emergence chronotypes for sympatric Rhagoletis brncici Frías and Rhagoletis conversa (Bréthes) (Diptera, Tephritidae), Revista Brasileira de Entomologia 63 (3), pp. 195-198 : 197

Rhagoletis conversa

It has been documented that predation at the time of third-instar emergence from fruits is one of the factors that affects larval survival ( Aluja et al., 2005). The other factor that may influence larval emergence behavior in the species studied is the evasion of potential diurnal predators that have been described for Tephritidae larvae, such as mice ( Thomas, 1993, 1995), ants and wasps ( Aluja et al., 2005), and also several parasitic microhymenopteran species ( Maier, 1981; Ovruski et al., 2000; Bomfim et al., 2007; Hernández-Ortiz et al., 1994; Sivinski et al., 2001, 1997; Taira et al., 2013).

Moreover, the interespecific allochrony detected in larvae emergence, for both Rhagoletis species, may be also be related to the differences in geographical distribution found in these species; R. brncici tends to inhabit cooler places in the sub-Andean region of central and southern Chile, whereas R. conversa is distributed in warmer localities in central and northern Chile ( Frías et al., 1984; Frías, 2001). This kind of pattern has been found in species of other genera of Thephritidae such as Bactrocera ( Danjuma et al., 2014) and Ceratitis ( Duyck and Quilici, 2002) .

As a final remark, we can comment that it is necessary to further study larval exit timing differences in these two Rhagoletis species in allopatric populations, considering climatic variables and their respective Solanum host plants, in order to test if temporal difference between R. conversa and R. brncici larvae may fit to potential physiological adaptations of these flies within their distribution. Moreover, it would also be of great interest to compare this with sympatric populations in order to test for differences in emergence regarding allopatric populations. These comparisons may allow us to disentangle whether changes in larval exit evolved as an isolating mechanism when these two species overlap.