Portal de Periódicos da CAPES

Neue Meganeuridae aus dem Namurium von Hagen-Vorhalle (BRD) und die Phylogenie der Meganisoptera (Insecta, Odonata)

2008; Pensoft Publishers; Volume: 36; Issue: 1-3 Linguagem: Inglês

10.1002/mmnd.19890360127

1860-1324

Carsten Brauckmann, Wolfgang Zessin,

Lepidoptera: Biology and Taxonomy

The hitherto known members of the Odonata families "Eugeropteridae"︁, "Erasipteridae"︁, Paralogidae, Meganeuridae, and Triadotypidae are critically reviewed; their phylogenetic relationships are examined. Most important for these studies are three new finds from the Upper Namurian B from the famous insect bearing locality of Hagen-Vorhalle (Ruhr area, FRG). They represent a new genus and species of the Meganeuridae — Namurotypus sippeli n.g. n.sp. — and are the stratigraphically oldest known and most completely preserved specimens of this family as well. One of them for the first time shows the abdominal appendages of the male. For these — besides Erasipteroides valentini — most ancient unequivocally datable dragonflies at all the following features can be regarded as characteristic: (1) long antennae (more than twice as long as the head), (2) presumably rather small eyes, (3) small mandibles, (3) 4 tarsal segments (basitarsus + 3 tarsi), (5) unpaired median claw at the posttarsus, (6) only slightly oblique thoracic segments, (7) presence of 11 backwardly tapering abdominal segments, (8) presence of a terminal filum (as defined by Henning, 1968), (9) long paired penes at sternit 8, (10) large, leaf-like styli at the posterior end of sternit 8 (or perhaps to be interpreted as fused gonostyli + gonocoxites attached to sternit 9, respectively), (11) long cerci curved vertically like a reverse S, (12) obvious lack of accessory copulation apparatus at abdominal sternites 2 and 3, and (13) beginning of sclerotisation in the presubcostal area. Additionally, in strong contrast to the reconstruction of a meganeurid dragonfly (Meganeura monyi) by Handlirsch (1925), the fore wings do not overlap the hind wings. With a wing-span of 32 cm, Namurotypus sippeli is the largest known Namurian insect. These results on the morphology of Namurotypus sippeli allow a new and more appropriate reconstruction of the complete animal and furthermore lead to the following interpretation of the habit: (1) The animals probably were not very fast and agile during flight and mainly may have moved by gliding (with the abdominal appendages also operating as stabilizators); (2) secondary copulation is less probable; (3) it cannot be excluded that predatory feeding of the imagines was restricted. The critical review of the remaining taxa made it necessary to create three additional new genera: (1) Solutotherates n. g. with the type species S. analis (Carpenter, 1980) (incertae familiae) from the Westphalian D of Pennsylvania (USA), (2) Erasipteroides n. g. with the type species E. valentini (Brauckmann, 1985) (family "Erasipteridae"︁) from the Upper Namurian B of Hagen-Vorhalle (FRG), and (3) Whalleyala n. g. with the type species W. bolsoveri (Whalley, 1979) (family "Erasipteridae"︁) from the Westphalian A of Derbyshire (Great Britain). The results of the phylogenetic studies are summarized in a hypothetic dendrogram. Most probably the Paralogidae + Meganeuridae + Triadotypidae (= Meganisoptera sens. nov.) represent a monophyletic unit, whereas the "Eugeropteridae"︁ and "Erasipteridae"︁ are paraphyletic. Presumably the Meganisoptera as well as the recent Odonata have their origin in species of the "Erasipteridae"︁.