We suggest that experimental hybrid crosses are to be conducted for analysis of possible
prezygotic and postzygotic barriers installed in the Panstrongylus and Nesotriatoma genus.
Classic studies of plants on mine tailings in Europe (Antonovics, 2006 and references therein) clearly demonstrated that rapid and repeated evolution of metal tolerance is often associated with the evolution of
prezygotic isolating mechanisms, including the evolution of both self-compatibility (Mousset et al, 2016 and references therein) and earlier flowering in metal-tolerant populations (Antonovics, 2006 and references therein).
Natural history and behavioral insights divide reproductive barriers into
prezygotic and postzygotic isolating factors [2].
Weak
prezygotic isolating mechanisms in threatened Caribbean Acropora corals.
Therefore, in populations in which both diploid and tetraploid cytotypes occur, or in areas in which diploid and tetraploid populations are in relatively close proximity, selection to reduce the frequency of intercytotype crosses may result in character displacement for traits that influence the likelihood such crosses occur, i.e.,
prezygotic isolation.
Absence of a
prezygotic behavioural barrier to gene flow between the two sympatric morphs of the squat lobster Munida gregaria (Fabricius, 1793) (Decapoda: Anomura: Galatheidae).
Postcopulatory,
prezygotic isolation in flour beetles.
(2011a) suggested that a
prezygotic explanation is more likely owing to the lack of hybrid individuals and strong Wahlund effect in areas of sympatry.
This process occurs due to differences in the acrosome and/or flagellum which produce
prezygotic incompatibility (between sperms and eggs), because there are receptors located in these structures that are used for fertilization in some marine invertebrates, especially those with external fertilization (Pitnick et al., 2009).
Prezygotic barriers resulting from pollenpistil incompatibility, where pollen grain germination and pollen tube growth of one species is inhibited by the stigma of another species (BURSON & YOUNG, 1983) are quite common.