{{Taksoboks
| bilde=OmmadissW.jpg
| bildetekst=
| norsknavn=Sikader
| vitenskapsnavn=Auchenorrhyncha
| overgrupper=nebbmunner, <br>vingede insekter, <br>insekter}}
{{Taksoboks-gruppe
| artstall=303 i Norge<br>? i verden
| habitat=mest utbredt i tempererte soner
| utbredelse=hele verden}}
* Cicadomorpha
* Fulgoromorpha

'''Sikader''' (Auchenorrhyncha) er små insekter som lever av å suge saften ut av planter. Lengden varierer fra 0,5 til noen centimeter.

Mange av land- og skogbruk, og for hageeiere. 

== Systematisk Inndeling ==
Et latinsk familenavn ender med ''...idae'', og et navn på en overfamilie på  ''...oidea''.

* Nebbmunner (Hemiptera)
** underorden '''Plantesugere''' (Homoptera) [kunstig gruppe]
*** gruppe '''Sikader''' (Auchenorrhyncha) - 303 arter i Norge.
**** delgruppe '''Cicadomorpha'''
***** overfamilien '''Cicadoidea''' 
****** familien Tettigarctidae 
****** familien Sangsikader (Cicadidae)
***** overfamilien '''Skumsikader''' (Cercopoidea)
****** familien «Små skumsikader» (Cercopidae)
****** familien «Stor skumsikader» (Aphrophoridae)
****** familien Machaerotidae
****** familien Clastopteridae
***** overfamilien '''Membracoidea'''
****** familien Dvergsikader (Cicadellidae)
****** familien Melizoderidae
****** familien Aetalionidae
****** familien Hornsikader (Membracidae)
**** delgruppe '''Fulgoromorpha''' 
***** familien Achilidae
***** familien Achilixiidae
***** familien Acanaloniidae
***** familien Cixiidae 
***** familien Delphacidae
***** familien Derbidae 
***** familien Dictyopharidae
***** familien Eurybrachidae
***** familien Flatidae
***** familien Fulgoridae
***** familien Gengidae 
***** familien Hypochthonellidae
***** familien Issidae
***** familien Kinnaridae 
***** familien Lophopidae
***** familien Meenoplidae 
***** familien Nogodinidae 
***** familien Ricaniidae
***** familien Tettigometridae
***** familien Tropiduchidae

{{Taxobox
| image = Graphocephala_coccinea_6.jpg
| image_caption = Red-banded leafhopper, ''Graphocephala coccinea''
| name = Cicadas, leafhoppers, etc
| regnum = Animalia
| phylum = Arthropoda
| classis = Insecta
| ordo = Hemiptera
| subordo = '''Auchenorrhyncha'''
| subdivision_ranks = Infraorders
| subdivision = 
Cicadomorpha<br>
Fulgoromorpha<br>
}}

The '''Auchenorrhyncha''' is the suborder of the Hemiptera which contains most of the familiar members of what was called the '''Homoptera''' - groups such as cicadas, leafhoppers, treehoppers, planthoppers, and spittlebugs. The aphids and scale insects are the other well-known "Homoptera", and they are in the suborder Sternorrhyncha. Distributed worldwide, all members of this group are plant-feeders. It is also common for Auchenorrhyncha to produce either audible sounds or substrate vibrations as a form of communication.

==Classification==

There has been a fair bit of debate and uncertainty as to whether the Auchenorrhyncha is a monophyletic group or not; some authors, believing it was not, split it into two suborders, the '''Clypeorrhyncha''' (= Cicadomorpha) and the '''Archaeorrhyncha''' (= Fulgoromorpha). In the last 10 years there has been evidence to support this interpretation, and the most recent research indicates that the Auchenorrhyncha are indeed a paraphyletic lineage.

A classification of the Auchenorrhyncha is as follows:<ref>C. H. Dietrich in Resh, V. H. & Carde, R. T. (Eds.) 2003 Encyclopedia of Insects. Academic Press.</ref>

* Infraorder Cicadomorpha (Clypeorrhyncha, Clypeata)
** Superfamily Cercopoidea (spittlebugs, froghoppers)
***Aphrophoridae
***Cercopidae
***Clastopteridae
***Machaerotidae
** Superfamily Cicadoidea (cicadas)
***Cicadidae (Platypediidae, Plautillidae, Tettigadidae, Tibicinidae)
***Tettigarctidae (hairy cicadas)
**Superfamily Membracoidea (Cicadelloidea)
***Aetalionidae (Biturritiidae)
***Cicadellidae (Eurymelidae, Hylicidae, Ledridae, Ulopidae,leafhoppers)
***Melizoderidae
***Membracidae (Nicomiidae, treehoppers)
***Myerslopiidae (Cicadellidae, in part)
*Infraorder Fulgoromorpha (Archaeorrhyncha, planthoppers)
**Superfamily Fulgoroidea
***Acanaloniidae
***Achilidae
***Achilixiidae
***Cixiidae
***Delphacidae
***Derbidae
***Dictyopharidae
***Eurybrachidae
***Flatidae
***Fulgoridae (lanternflies)
***Gengidae
***Hypochthonellidae
***Issidae
***Kinnaridae
***Lophopidae
***Meenoplidae
***Nogodinidae
***Ricaniidae
***Tettigometridae
***Tropiduchidae