An exploration of the complex biogeographical history of the Neotropical banner-wing damselflies (Odonata: Polythoridae)

Abstract

Background: The New World Tropics has experienced a dynamic landscape across evolutionary history and harbors a high diversity of flora and fauna. While there are some studies addressing diversification in Neotropical vertebrates and plants, there is still a lack of knowledge in arthropods. Here we examine temporal and spatial diversification patterns in the damselfly family Polythoridae, which comprises seven genera with a total of 58 species distributed across much of Central and South America. Results: Our time-calibrated phylogeny for 48 species suggests that this family radiated during the late Eocene (3 3 Ma), diversifying during the Miocene. As with other neotropical groups, the Most Recent Common Ancestor (MRCA) of most of the Polythoridae genera has a primary origin in the Northern Andes though the MRCA of at least one genus may have appeared in the Amazon Basin. Our molecular clock suggests correlations with some major geographical events, and our biogeographical modeling (with BioGeoBEARS and RASP) found a significant influence of the formation of the Pebas and Acre systems on the early diversification of these damselflies, though evidence for the influence of the rise of the different Andean ranges was mixed. Diversification rates have been uniform in all genera except one-Polythore-where a significant increase in the late Pliocene (~3 mya) may have been influenced by recent Andean uplift. Conclusion: The biogeographical models implemented here suggest that the Pebas and Acre Systems were significant geological events associated with the diversification of this damselfly family; while diversification in the tree shows some correlation with mountain building events, it is possible that other abiotic and biotic changes during our study period have influenced diversification as well. The high diversification rate observed in Polythore could be explained by the late uplift of the Northern Andes. However, it is possible that other intrinsic factors like sexual and natural selection acting on color patterns could be involved in the diversification of this genus.

Morphological variation and reproductive isolation in the Hetaerina americana species complex

“…These characters could be body and wing coloration (i.e., behavioral/sexual isolation, e.g., Calopteryx ), the shape of the male caudal appendages and the female prothorax (i.e., mechanical/sensorial isolation, e.g., Enallagma , Ischnura ) and even the shape of the secondary male genitalia (i.e., mechanical/sensorial isolation, e.g., Calopteryx , Polythore , Chalcopteryx , etc.) 19 – 21 . Besides these characters, different behaviors such as territoriality and complex courtships can be involved in the mating process and species recognition systems 22 .…”

How old are dragonflies and damselflies? Odonata (Insecta) transcriptomics resolve familial relationships

“…Relationships in Zygoptera have previously been considered chaotic. Past studies have only resolved parts of the Zygoptera family tree [13][14][15][16][17] and a fully resolved phylogeny of Zygoptera didn't exist until this present study.…”

A shallow-scale phylogenomics approach reveals parallel patterns of diversification among sympatric populations of cryptic Neotropical aquatic beetles (Coleoptera: Noteridae)

“…The relationship between geography and patterns of organismal diversity has long been considered in the study of Neotropical biota (Rull, 2020), with investigations varying in focal spatial and temporal scales (e.g. Harvey et al, 2016; 2017; Toussaint and Gillet, 2018; Maestri and Duarte, 2020; Rull, 2020; Sánchez-Herrera et al, 2020; Johnson; et al, 2023). However, biogeographic hypotheses explaining the high levels of Neotropical biodiversity often focus on recent timescales (e.g.…”