Courtship interactions in interspecific and intergeneric crossings of species from Osphronemidae family
Reproductive behavior; reproductive isolation; agonistic interactions; fish cytogenetics; hybridization.
Intra and interspecific genetic and phenotypic variability are essential aspects of genetic improvement. In this context, crossbreeding in fish with evolutionarily distinct genetic backgrounds has contributed to the production of functional products with remarkable market value. Artificial interspecific hybrids aimed at the ornamental market have enhanced morphological, physiological, or behavioral traits of economic interest. Among the most globally traded species, Betta splendens (Osphronemidae) stands out. Due to its beauty and hardiness, it drives an enormous production chain. Given its pronounced sexual dimorphism and high level of agonistic interactions among males, this species is commonly referred to as a fighting fish, primarily suggesting morphological characteristics shaped by intrasexual sexual selection. Analyses of pre- and post-zygotic reproductive isolation mechanisms involving the genera Betta, Trichogaster, Trichopodus, and Macropodus are necessary for their captive management and the development of hybridization protocols within the family. Thus, reproductive isolating mechanisms were investigated, including analyses of courtship interactions in interspecific and intergeneric crosses within the Osphronemidae family and the cytogenetic patterns of the species. The first chapter assesses the reproductive behavioral isolation of family species and its associations with the level of phylogenetic proximity. The second chapter explores the cytogenetic diversification of six commercially relevant Osphronemid species and their potential role as post-zygotic reproductive isolation mechanisms, guiding practices potentially applicable to interspecific hybridization and market enhancement within the family.