Phylogeny of the basal Odonatoptera (Insecta) from the Lower Carboniferous (Serpukhovian) of Central Western Argentina

PETRULEVICIUS J. F. Y GUTIÉRREZ, P. R.

Santo Domingo

Congreso; 8th International Conference on Fossil Insects, Arthropods & Amber; 2019

The aim of the work is to propose a phylogeny of the Odonatoptera basal to Paneodonatoptera based on wing characters. These basal odonatopterans correspond to five genera from the Lower Carboniferous, upper Serpukhovian (325-324 Ma) from La Rioja Province, Central West Argentina. Genera Eugeropteron and Geropteron come from Malanzán Formation and genera Tupacsala, Argentinala and Kirchnerala come from Guandacol Formation. These formations are considered lateral equivalents of two neighbour basins dominated by glacial events. Together with other two species of Xenopteraidae (Megasecoptera) this is the oldest diverse entomofauna with flying insects worldwide. Coincidentally with their antiquity, these basal Hydropalaeoptera recorded in the boundaries of the Hexapoda gap (325 Ma) share some plesiomorphies unique among insects, such as the radial sectors completely separated. Both sectors RA and RP are convex (+), being interpreted as the RP fused with the MA from the base of the wing. RP is convex while it is fused with MA, becoming concave (-) after arising of this latter. MA arising with strong Z-shaped kink which seems to operate as a flight device, analogous with the arculus in the Odonata crown group. In the latter group, all three veins (RA+RP+MA) run basally to the arculus together in a convex (+) triple stem. Other groundplan simplesiomorphy is the MP bending anteriorly, separated or fused but not ?captured? by the CuA. The Paneodonatoptera share the MP bending posteriorly and fused, ?captured? by the CuA, a synapomorphy obscured in the Odonata crown group. Argentinala has also six wings, with veined and possibly movable prothoracic wings; characters unique within Odonatoptera. The performing of the analysis shed light to the genealogical relationships of these basal taxa of Odonatoptera and coincides with the classification of Petrulevičius and Gutiérrez (2016). It shows the paraphyly of Eugeropteridae sensu Riek (1983) and Geroptera sensu Brodsky (1994) and Kukalová-Peck (2009). Bechly et al. (2001) warned that the monophyly of Geroptera was weakly founded. The most important morphological changes in wing venation in these basal groups go through the fusion of veins, principally in the medial, cubital and anal systems. The phylogeny resulted in Odonatoptera including Eugeroptera (Eugeropteridae: Eugeropteron lunatum Riek, 1983 and Tupacsala niunamenos Petrulevičius and Gutiérrez, 2016) and Palaeodonatoptera. Palaeodonatoptera including Kukaloptera (Kirchneralidae: Kirchnerala treintamil Petrulevičius and Gutiérrez, 2016) and Plesiodonatoptera. Plesiodonatoptera including Argentinoptera (Argentinalidae: Argentinala cristinae Petrulevičius and Gutiérrez, 2016) and Apodonatoptera. Apodonatoptera including Geroptera (Geropteridae: Geropteron arcuatum Riek, 1984) and Paneodonatoptera.