Too strict or too loose? Integrative taxonomic assessment of Bombus lapidarius complex (Hymenoptera: Apidae)

The latest progress of the taxonomy is theuse of integrative approach forspecies delimitation based on a multisource dataset.However, the taxonomic decision that should be made when convergence between the differentlines of evidence is not observedremains debated.Here,we investigate the consequences of the application of an "integration by cumulation" approach on the taxonomic statuseswithinthe Bombus lapidariuscomplex when usinganintegrative taxonomic framework (i.e. nuclear and mitochondrial markers along with reproductive traits)compared to a strict "integration by congruence"method.Our results show similar taxonomic conclusionswhatever the decision-making approach used except for one taxon. According to the differentiation observed in our integrative taxonomic framework, recent divergence time,and other field observationsfor this taxon, we assume that a too strict decision-makingmethodcould fail to detect recently diverged species. This is exemplified by the new species Bombus bisiculussp. n.occurring in South Italy and Sicily.