Global classification and evolution of brushlegged mayflies (Insecta: Ephemeroptera: Oligoneuriidae): phylogenetic analyses of morphological and molecular data and dated historical biogeography

Abstract

Oligoneuriidae is a Pantropical family of Ephemeroptera, with 68 species described in 12 genera. Three subfamilies are recognized: Chromarcyinae, with a single species from East Asia; Colocrurinae, with two fossil species from Brazil; and Oligoneuriinae, with the remaining species distributed in the Neotropical, Nearctic, Afrotropical and Palaearctic regions. Phylogenetic and biogeographical analyses were performed for the family based on 2762 characters [73 morphological and 2689 molecular (COI, 16S, 18S and 28S)]. Four major groups were recovered in all analyses (parsimony, maximum likelihood and Bayesian inference), and they were assigned to tribal level, namely Oligoneuriini, Homoeoneuriini trib. nov., Oligoneuriellini trib. nov. and Elassoneuriini trib. nov. In addition, Yawari and Madeconeuria were elevated to genus level. According to Statistical Dispersal-Vicariance (S-DIVA), Dispersal Extinction Cladogenesis (DEC) and divergence time estimation analyses, Oligoneuriidae originated ~150 Mya in the Gondwanan supercontinent, but was probably restricted to the currently delimited Neotropical region. The initial divergence of Oligoneuriidae involved a range expansion to Oriental and Afrotropical areas, sometime between 150 and 118 Mya. At ~118 Mya, the family started its diversification, reaching the Nearctic through dispersal from the Neotropical region and the Palaearctic and Madagascar from the Afrotropical region.

Unmasking a gap: A new oligoneuriid fossil (Ephemeroptera: Insecta) from the Crato Formation (upper Aptian), Araripe Basin, NE Brazil, with comments on Colocrus McCafferty

“…LPU 1696 was recovered with one autapomorphy: presence of incomplete gemination (76:0). Oligoneuriinae was recovered as monophyletic, with BT and RB values of 96 and 31 respectively, supported by three synapomorphies already found by Massariol et al [ 4 ], plus the absence of cubital intercalaries (74:1; new character). Relationships between its genera were not well resolved, with many taxa in polytomies.…”

“…In order to determine the phylogenetic relationships of LPU 1696, a cladistic analysis was performed using morphological data from the Oligoneuriidae matrix presented by Massariol et al [ 4 ]. Three new characters were proposed, and characters 32 (insertion of gill I) and 53 (orientation of vein RP2 of forewing in relation to RA) were recoded in the matrix according to our interpretation (see S1 and S2 Appendices ).…”

“…because their genera were already represented by other species, and the intention of the analysis was to unravel the phylogenetic position of LPU 1696 within Oligoneuriidae. Outgroup taxa were the same used by Massariol et al [ 4 ], from the related families Isonychiidae, Coloburiscidae, and Heptageniidae, which together with Oligoneuriidae compose the superfamily Heptagenioidea [ 10 , 12 ].…”

“…Among fossil mayflies, oligoneuriids (Oligoneuriidae) are especially rare. The family is divided into three subfamilies [ 2 , 4 ]: Colocrurinae McCafferty, 1990; Chromarcyinae Demoulin, 1953; and Oligoneuriinae Ulmer, 1914. Colocrurinae is a subfamily known only by fossils and comprises two species of the genus Colocrus McCafferty, 1990, both from the Crato Formation ( Colocrus indivicum McCafferty, 1990 and Colocrus magnum Staniczek, 2007).…”

Do mayflies (Ephemeroptera) support a biogeographic transition zone in South America?

“…An extended South American transition zone does not exist for Ephemeroptera. Despite the limitation in working with a single aquatic taxon (i.e., an ecological bias), we believe that at a certain point our results give independent information from many intra-order groups, e.g., families, that are very ancient, having diversified before the end of the Jurassic (Hubbard & Savage, 1981;Massariol, Takiya, & Salles, 2019;Zhou & Peters, 2003).…”