add site
services
publishers
database
health videos
toolbar
stats
live show
health store
more stuff
JOIN/LOGIN
| advertise add site services publishers database health videos
| | about toolbar stats live show health store more stuff JOIN/LOGIN |
Snakeflies are a group of insects in the order Raphidioptera, consisting of about 150 species. Together with the Megaloptera they were formerly placed within the Neuroptera, but now these two are generally regarded as separate orders. Snakeflies are predatory, both as adults and larvae. They can be quite common throughout temperate Europe and Asia, but in North America occur exclusively in the Western United States, namely in the Rocky Mountains and westward, including the southwestern deserts.
[edit] Anatomy and life cycleAdult snakeflies are characterized by having an elongate prothorax but no modification of the forelegs (as in Mantispidae). They have strong and relatively unspecialised mouthparts, and large compound eyes. Some species also have ocelli. The females typically have a long ovipositor, which they use to deposit their eggs into crevices in bark or rotting wood. The wings are similar in size, with a primitive venation pattern, and a thickened costal margin (or "pterostigma").[1] The larvae have large heads with projecting mandibles. The head and the first segment of the thorax are sclerotised, but the rest of the body is soft and fleshy. They have three pairs of true legs, but no prolegs. However, they do possess an adhesive organ on the abdomen, with which they can fasten themselves to vertical surfaces.[1] The final larval instar creates a cell in which the insect pupates. However, they do not create a cocoon, and the pupa is fully capable of movement, and often leaves its cell for another location before the adult emerges.[1] [edit] SystematicsThe Megaloptera, Neuroptera (in the modern sense) and Raphidioptera are very closely related, and the new name for this group is Neuropterida[2]. This is either placed at superorder rank, with the Endopterygota - of which they are part - becoming an unranked clade above it, or the Endopterygota are maintained as a superorder, with an unranked Neuropterida being a part of them. Within the endopterygotes, the closest living relatives of the neuropteridan clade are the beetles. The two extant families of snakeflies are the Raphidiidae and Inocelliidae. In addition, there are a number of extinct forms known only from fossils. Almost all known snakeflies belong to the suborder Raphidiomorpha. The single exception is the prehistoric family Priscaenigmatidae, sometimes placed in a suborder Priscaenigmatomorpha but more likely a basal lineage that does not warrant the establishment of such a redundant monotypic taxon.[3] Fossil snakeflies are known from the Early Cretaceous onwards and these are not even the basalmost forms, suggesting their origin lies deep in the Jurassic at least. In fact, the earliest Neuroptera are from the Permian and thus snakefly ancestors probably even predate the Mesozoic also. Fossil Raphidiomorpha taxa are:[3]
[edit] Footnotes
[edit] References
| |||||||||||||||||||||||||||||
| ↑ top of page ↑ | about thumbshots |
