Odonatoptera
Encyclopedia
The Odonatoptera are a superorder (sometimes treated as an order
) of ancient winged insects, placed in the Palaeoptera which probably form a paraphyletic group however. The dragonflies and damselflies are the only living members of this group, which was far more diverse in the late Paleozoic
and contained gigantic species, including the griffinflies (colloquially called "giant dragonflies", although they were not dragonflies in the strict sense) of the order Protodonata
. This lineage dates back at least to the Bashkirian
, not quite 320 million years ago.
of winged insects that stands outside the Neoptera
. But various authors' analyses have yielded any one of three mutually exclusive phylogenies, or some variant thereof: The least problematic (in a taxonomic sense) view is that the Odonatoptera are the sister taxon of the Ephemeropteroidea (the mayfly lineage), and that the Palaeodictyopteroidea
are either their sister taxon or a basal assemblage, all within a monophyletic Palaeoptera. But few recent analyses have supported this. Rather, it seems more and more likely that the Odonatoptera are the sister taxon of the Neoptera, making the "Palaeoptera" paraphyletic. The third view places the mayfly lineage as sister taxon of the neopterans, with the Odonatoptera as most primitive winged insects; it has seen little support in recent decades however.
While the internal subdivision of this superorder is subject to much dispute and far from resolved, at least the coarser divisions seem to be fairly stable by now. Six orders are generally recognized, as well as two families
incertae sedis
and a further "family" that is almost certainly not monophyletic. Ordered from the most ancestral to the most advanced, these are:
In some treatments, the Odonata are expanded to include all these taxa with the exception of the "Erasipteridae", Geroptera and Protodonata; this group is treated as an unranked clade
Odonatoclada in the scheme used here. Where the Odonata are defined loosely, the term Odonatoidea is used instead of "Odonatoptera".
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
) of ancient winged insects, placed in the Palaeoptera which probably form a paraphyletic group however. The dragonflies and damselflies are the only living members of this group, which was far more diverse in the late Paleozoic
Paleozoic
The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...
and contained gigantic species, including the griffinflies (colloquially called "giant dragonflies", although they were not dragonflies in the strict sense) of the order Protodonata
Protodonata
Meganisoptera is an extinct order of very large to gigantic insects often called griffenflies. The order was formerly named Protodonata for their similar appearance and relation to dragonflies...
. This lineage dates back at least to the Bashkirian
Bashkirian
The Bashkirian is in the ICS geologic timescale the lowest stage or oldest age of the Pennsylvanian, the youngest subsystem of the Carboniferous...
, not quite 320 million years ago.
Systematics and taxonomy
There is little consensus about the relationships of the Odonatoptera. What is certain is that they are a cladeClade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
of winged insects that stands outside the Neoptera
Neoptera
Neoptera is a classification group that includes almost all the winged insects, specifically those that can flex their wings over their abdomens...
. But various authors' analyses have yielded any one of three mutually exclusive phylogenies, or some variant thereof: The least problematic (in a taxonomic sense) view is that the Odonatoptera are the sister taxon of the Ephemeropteroidea (the mayfly lineage), and that the Palaeodictyopteroidea
Palaeodictyopteroidea
The Palaeodictyopteroidea or Paleodictyopterida are an extinct superorder of Palaeozoic beaked insects, characterised by unique mouthparts consisting of 5 stylets. They represent the first important terrestrial herbivores, and the first major group of herbivorous insects...
are either their sister taxon or a basal assemblage, all within a monophyletic Palaeoptera. But few recent analyses have supported this. Rather, it seems more and more likely that the Odonatoptera are the sister taxon of the Neoptera, making the "Palaeoptera" paraphyletic. The third view places the mayfly lineage as sister taxon of the neopterans, with the Odonatoptera as most primitive winged insects; it has seen little support in recent decades however.
While the internal subdivision of this superorder is subject to much dispute and far from resolved, at least the coarser divisions seem to be fairly stable by now. Six orders are generally recognized, as well as two families
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
incertae sedis
Incertae sedis
, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...
and a further "family" that is almost certainly not monophyletic. Ordered from the most ancestral to the most advanced, these are:
- Order Geroptera (fossilFossilFossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
) - Family "Erasipteridae" (fossil; probably paraphyletic)
- Order ProtodonataProtodonataMeganisoptera is an extinct order of very large to gigantic insects often called griffenflies. The order was formerly named Protodonata for their similar appearance and relation to dragonflies...
(or Meganisoptera) – griffinflies or "giant dragonflies" (fossil) - Family Campylopteridae (fossil)
- Family Lapeyriidae (fossil)
- Order Protanisoptera (fossil)
- Order Triadophlebioptera (fossil)
- Order Protozygoptera (including Archizygoptera) (fossil)
- Order OdonataOdonataOdonata is an order of insects, encompassing dragonflies and damselflies . The word dragonfly is also sometimes used to refer to all Odonata, but the back-formation odonate is a more correct English name for the group as a whole...
– dragonfliesDragonflyA dragonfly is a winged insect belonging to the order Odonata, the suborder Epiprocta or, in the strict sense, the infraorder Anisoptera . It is characterized by large multifaceted eyes, two pairs of strong transparent wings, and an elongated body...
and damselfliesDamselflyDamselflies are insects in the order Odonata. Damselflies are similar to dragonflies, but the adults can be distinguished by the fact that the wings of most damselflies are held along, and parallel to, the body when at rest...
In some treatments, the Odonata are expanded to include all these taxa with the exception of the "Erasipteridae", Geroptera and Protodonata; this group is treated as an unranked clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
Odonatoclada in the scheme used here. Where the Odonata are defined loosely, the term Odonatoidea is used instead of "Odonatoptera".