Out of Africa: Biogeography and diversification of the pantropical pond skater genus Limnogonus Stål, 1868 (Hemiptera: Gerridae)

Abstract

Gondwanan vicariance, long‐distance dispersal (LDD), and boreotropical migration have been proposed as alternative hypotheses explaining the pantropical distribution pattern of organisms. In this study, the historical biogeography of the pond skater genus Limnogonus was reconstructed to evaluate the impact of biogeographical scenarios in shaping their modern transoceanic disjunction. We sampled almost 65% of recognized Limnogonus species. Four DNA fragments including 69 sequences were used to reconstruct a phylogram. Divergence time was estimated using a Bayesian relaxed clock method and three fossil calibrations. Diversification dynamics and ancestral area reconstruction were investigated by using maximum likelihood and Bayesian approaches. Our results showed the crown group of Limnogonus originated and diversified in Africa in the early Eocene (49 Ma, HPD: 38–60 Ma), subsequently expanding into other regions via dispersal. The colonization of the New World originated from the Oriental Region probably via the Bering Land Bridge in the late Eocene. Two split events between the Old World and New World were identified: one between Neotropics and Oriental region around the middle Oligocene (30 Ma, HPD: 22–38 Ma), and the other between Neotropics and Africa during the middle Miocene (14 Ma, HPD: 8–21 Ma). The evolutionary history of Limnogonus involved two biogeographical processes. Gondwanan vicariance was not supported in our analyses. The diversification of Limnogonus among Africa, Oriental, and Neotropical regions corresponded with the age of land bridge connection and dispersed as a member associated with the broad boreotropical belt before local cooling (34 Ma). The current transoceanic disjunctions in Limnogonus could be better explained by the disruption of “mixed‐mesophytic” forest belt; however, the direct transoceanic LDD between the Neotropics and Africa could not be ruled out. In addition, the “LDD” model coupled with island hopping could be a reasonable explanation for the diversification of the Oriental and Australian regions during the Oligocene.

The influence of the Gondwanan breakup on the biogeographic history of the ziziphoids (Rhamnaceae)

“…However, other tribes predominantly distributed in the Southern Hemisphere, such as Colletieae, Gouanieae, or Phyliceae, evolved following Oligocene and Neogene LDD events, and were not driven by vicariance. In line with multiple other studies (Bechteler et al., ; Kayaalp, Stevens, & Schwarz, ; Nauheimer et al., ; Ye, Zhen, Zhou, & Bu, ), our reconstructions highlight that the intuitive idea that a taxon's distribution with tribes on the three Southern Hemisphere continents would necessarily be the result of vicariance might be wrong, even if the group was old enough. Support for Gondwanan vicariance as a biogeographic driver, however, is rare in taxa from the Late Cretaceous, but has also been documented (Luebert et al., ; Toussaint et al., ).…”

Phylogeny and diversification of the true water bugs (Insecta: Hemiptera: Heteroptera: Nepomorpha)

“…Rabosky et al., ; Alencar et al., ) and insects (e.g. Fagua et al., ; Ye et al., ). In contrast, few rigorous studies of the diversification of organisms in the Mesozoic have been performed (for insects, mammals and plants, see e.g., Condamine et al., ; Wildman et al., ; Mao et al., ).…”

Assessing the existence of pantropical butterflies: A review of accurate taxonomy, biogeography and life history traits

“…The NALB had two routes that connected the biotas of North America and Europe: the De Geer route in the north (persisting until 40 Ma) and the Thulean route in the south (present until 50 Ma) (Lomolino et al, 2017). Global cooling after the Oligocene (34 Ma) triggered disruption of this continuous forest belt (Ye et al, 2017), preventing further dispersal of tropical organisms. The BLB, connecting Asia and North America, remained throughout the majority of the Cenozoic (until approximately 5.5-4.8 Ma) and served as a main pathway for inter-continental colonisations in the absence of the NALB.…”