Round-headed leaf hoppers

Round-headed leaf hoppers
	Rhododendron cicada ( Graphocephala fennahi )
Systematics
Trunk :	Arthropod (arthropoda)
Class :	Insects (Insecta)
Subclass :	Flying insects (Pterygota)
Order :	Schnabelkerfe (Hemiptera)
	Cicadas (Auchenorrhyncha)
Subordination :	Round-headed leaf hoppers
Scientific name
	Cicadomorpha
	Evans , 1946

The cicadas (Auchenorrhyncha) were often divided into two large groups (suborders), the pointed head cicadas (Fulgoromorpha) and the round head cicadas (Cicadomorpha). Since this is probably not a monophyletic taxon , the term “cicadas” continues to be used mainly because of its wide distribution (also in textbooks) and from tradition. There are more than 33,000 species of Cicadomorpha in over 5,000 genera and 11 families.

Way of life

Just like the pointed-head cicadas, the round-headed cicadas are terrestrial insects that can fly, run and usually jump well. Many, not just the singing cicadas, sing, whereby the chants of many small cicadas are inaudible to the human ear.

Cicadomorpha suckle on plants, usually xylem or phloem , only Typhlocybinae suck on cell contents ( parenchyma ). Many endosymbiotic bacteria and fungi, which live in particular areas of the fatty tissue, enable the plant juices to be used. Some species produce honeydew and are symbiotic with ants .

morphology

Basic plan Cicadomorpha

The head is almost immovably connected to the thorax. On the underside, more or less between the front hips, a three-part proboscis rises. The Cicadomorpha have four wings with many veins, which are all transparent and are usually folded like a roof over their backs when they are at rest. The forewings are usually coarser and often colored differently than the hind wings, in flight the forewings and hind wings are functionally connected to one another. The 1st and 2nd anal arteries in the clavus of the forewings open separately into the posterior margin of the wing. There is no radial artery in the hind wing. There is no tegula at the base of the forewings. In some species the wings are shortened and polymorphic.

There are also systematically important differences to the Fulgoromorpha in the structure of the internal genitalia.

There are furrows and seams on the head, no ridges or keels (as in the Fulgoromorpha). The clypeus is arched forward and mostly clearly visible from above, which is where the name “round head cicadas” comes from. There are two ocelles or no ocelles. The ocelles and the antennae are between the complex eyes. The antenna flagellum is usually short and bristle-shaped.

Outline of the Cicadomorpha

A cicada orni. from the family of singing cicadas (Cicadidae)

Superfamily Membracoidea with the following families:

Cicadellidae (= Jassidae, dwarf cicadas)
Membracidae (humpback hoppers)
Aetalonidae (= false humpback hoppers ; closely related to humpback hoppers , smaller pronotum, scutellum with keel, only approx. 40 species, seven genera, both in the New World and in the Orientalis)

Melizoderidae (= cicadas; pronotum extended forward like a helmet, only 8 species in Chile and Argentina)

Myerslopiidae (= moss cicadas; only about 15 species in New Zealand and Chile, small, only 2-4 mm, live in moss)

Superfamily Cercopoidea with the following families (traditional system according to Strümpel 2010)

Cercopidae (blood-hoppers)
Aphrophoridae (leafhoppers)
Clastopteridae (= cicadas, shield-shaped habitus similar to ladybirds, approx. 90 species in North and South America)
Machaerotidae (= tube cicadas, larvae form species-specific tubes for protection; approx. 120 species, in the tropics of the Old World and Australia)

Superfamily Cicadoidea with the following families:

Tettigarctidae (= fur sing cicadas, furry hairy, communication with substrate vibration, larvae suckle on eucalyptus roots, only a recent genus with two species in Australia)
Cicadidae (singing cicadas)

The status of another family, the Epipygidae, is controversial. They probably belong to the Aphrophoridae.

Phylogeny

The relationship of the large groups of the Hemiptera to one another, the Cicadomorpha, Fulgoromorpha , Sternorrhyncha , Coleorrhyncha and Heteroptera , whose monophyly (at least as far as the recent groups are concerned) is generally accepted today, is a difficult, and to this day unsolved scientific problem (cf. .). The traditional system combines the Cicadomorpha and Fulgoromorpha to the Auchenorrhyncha or Cicadas, and these with the Sternorrhyncha to the Homoptera . However, while the Homoptera are considered an artificial group in almost all recent analyzes and today have only a few supporters, the position of the cicadas is an open problem. Although the possible morphological autapomorphies of the cicadas, especially the complex tymbal organ in the abdomen, but also the bristle-shaped flagellum of the antennae, the (eponymous) position of the origin of the labium and other, more difficult to see features (such as the structure of the mechanism of wing coupling and the fine structure of the Wing joints) seemed convincing for many editors, other morphological features, such as the fine structure of the digestive tract and the head capsule, speak against it. The analysis of the relationship on the basis of homologous DNA sections, which here is almost exclusively based on features of the mtDNA , the independent genetic material of the mitochondria , seemed to have decided the matter against the monophyly of the leafhoppers in the mid-1990s. According to recent studies, the situation is more complex. Due to the long history of splitting (according to the fossil record probably already in the Permian ), the sequence has mutated so often in more variable sections that every phylogenetic signal has been lost ("saturation"), and because of the very different evolutionary speed, so-called long -branch attraction artefacts , in which very different sequences are “pushed” to the edge and thus a false relationship between affected taxa can be faked. More recent analyzes with better taxon coverage and consideration of larger parts of the mtDNA still come up with contradicting results.

literature

Hans Strümpel: The cicadas . In: The New Brehm Library . tape 668 . Westarp Sciences, Hohenwarsleben 2010.
G. Kunz: Cicadas - the insects of the 21st century? (Hemiptera, Auchenorrhyncha). Entomologica Austriaca 18, 105-123; 2011, pdf:

Individual evidence

↑ ^a ^b Jason R. Cryan & Julie M. Urban (2012): Higher-level phylogeny of the insect order Hemiptera: is Auchenorrhyncha really paraphyletic? Systematic Entomology 37 (1): 7-21 doi : 10.1111 / j.1365-3113.2011.00611.x
↑ TH Buorgoin & BC Campbell inferring a phylogeny for Hemiptera: Falling into the 'Autapomorphic Trap'. Denisia 4: 67-82.
↑ Nan Song, Shiheng An, Xinming Yin, Wanzhi Cai, Hu Li (2016): Application of RNA-seq for mitogenome reconstruction, and reconsideration of long-branch artifacts in Hemiptera phylogeny. Scientific Reports 2016; 6: 33465. Doi : 10.1038 / srep33465
↑ Yuan Wang, Jing Chen, Li-Yun Jiang, Ge-Xia Qiao (2015): Hemipteran Mitochondrial Genomes: Features, Structures and Implications for Phylogeny. International Journal of Molecular Sciences 16: 12382-12404. doi : 10.3390 / ijms160612382

[Cryan-1] Jason R. Cryan & Julie M. Urban (2012): Higher-level phylogeny of the insect order Hemiptera: is Auchenorrhyncha really paraphyletic? Systematic Entomology 37 (1): 7-21 doi : 10.1111 / j.1365-3113.2011.00611.x

[2] TH Buorgoin & BC Campbell inferring a phylogeny for Hemiptera: Falling into the 'Autapomorphic Trap'. Denisia 4: 67-82.

[3] Nan Song, Shiheng An, Xinming Yin, Wanzhi Cai, Hu Li (2016): Application of RNA-seq for mitogenome reconstruction, and reconsideration of long-branch artifacts in Hemiptera phylogeny. Scientific Reports 2016; 6: 33465. Doi : 10.1038 / srep33465

[4] Yuan Wang, Jing Chen, Li-Yun Jiang, Ge-Xia Qiao (2015): Hemipteran Mitochondrial Genomes: Features, Structures and Implications for Phylogeny. International Journal of Molecular Sciences 16: 12382-12404. doi : 10.3390 / ijms160612382