Scarabaeidae

Gold Shiny rose chafer ( Cetonia aurata )

The scarab beetles (Scarabaeidae ) are a family in the order of the beetles ( Coleoptera), which summarizes very different animals. The approximately 27,000 species in 1600 genera very large, globally distributed group consists of several well-defined sub-families and a number of those whose phylogenetic position is still unclear. The Artanzahl the group is probably much higher because many large sub-groups, such as the Melolonthinae are still little explored. The systematics of the scarab beetle was heavily restructured recently and many subfamilies were elevated to the rank of a family within the superfamily Scarabaeoidea. Depending on the author, the number of specified subfamilies varies significantly.

Features

Beetle

The adult beetles are 2.0 to 160.0 millimeters long. Your body shape is variable, ranging from ovate, ovate - flattened and rectangular to cylindrical. Their color is variable. Many species are highly colored and some have a metallic sheen. One of scales or hairs can be constructed. The head is rarely angled slightly downward. The sensors are usually zehngliedrig, very rarely even neungliedrig and have a three - to seven-membered sensor lobe. The last links are hairless at the Melolonthinae, Dynastinae, Rutelinae, Cetoniinae, Trichiinae and Valginae in the Aphodiinae and Scarabaeinae they are provided with Toment. The compound eyes are partially divided and have fully developed ( eucone ) ommatidia. The face plate ( clypeus ) carries tubercle or horn- like projections in some species. The labrum is well expressed in the rule and is in some species over the top of the face plate out. The mandibles are designed differently and rich in many species over the tip of the labrum addition. The Maxillarpalpen are four members, the labial palps tripartite.

Also, the pronotum is made ​​variable and can carry tubercle or horn- like projections in some species. The wing covers ( elytra ) are curved flat or convex and contribute in some species longitudinal grooves. The pygidium is covered in the Aphodiinae of the elytra, otherwise it is in most other subfamilies free. The triangular, flat to parabolic tag ( scutellum ) may be free, or be hidden. The hips ( coxae ) of legs are inclined or conical. The rails ( tibiae ) of the front legs are either two -, three - or four- dentate or cut on the outer edge. Your Apex carries a spur. The tibiae of the remaining legs are slender and strong, meeting at its apex one or two spurs. In some species the Scarabaeinae the tarsi of the front legs are missing. The claws are made ​​variable. They are the same or different large, simple or toothed. A Empodium formed.

The abdomen has six visible sternites. The seven functional spiracles are located at the Aphodiinae and Scarabaeinae in the Pleuralmembranen, and most other subfamilies they are in the Pleuriten, the sternites and tergites. The genitalia of the males are made ​​variable. they have a double lobe or are fused.

Larvae

The larvae have a C- shaped curved body. In some species, such as most Scarabaeinae, they are a little bumpy. Their antennae are four members in the rule. Simple eyes ( ocelli ) are not formed in most species, they are found only in some Dynastinae and Cetoniinae. A Frontoclypealnaht formed. The tip of the labrum is rounded or overlap -like. The nasopharynx is as rounded or overlap -like and asymmetric. The Galea and lacinia are clearly separated from each other at the Aphodiinae and Scarabaeinae or grown in the other subfamilies to Mala. A maxillary Stridulationsorgan is usually trained. The spiracles are sieve-like ( cribriform ). The legs are tripartite in Scarabaeinae, otherwise five-membered. You have no organ for sound production. In most species claws are formed. On the ventral side of the last abdominal segment, a fleshy lobe is formed in some species.

Way of life

The lifestyle of the scarab beetle is extremely different. It ranges from ordinary life outdoors through to specialized way of life that is highly adapted to life with social insects, or even includes the brood care, in which the imagos live together together with the breeding of them cherished. The food ranges from dung, carrion, humus and fungi living up to all parts plants. There are many types that are considered beneficial insects, such as some types of Scarabaeinae and Aphodiinae, whereas some eating of plant species, such as from the subfamilies Melolonthinae, Rutelinae and Dynastinae among serious pests in agriculture and forestry. In the lowlands of Peru in 2008 was the first time a Scarab Beetle, Deltochilum valgum, discovered that hunts and eats millipedes with fondness.

Systematics and Taxonomy

The systematics of the scarab beetle was heavily restructured in recent years. Once within the superfamily Scarabaeoidea next to the family of scarab beetles very long time only the Schrötern ( Lucanidae ) was granted the status of a family, is meanwhile the view through that the subfamilies of the family of origin are mostly to be seen as their own families.

The monophyly of the family is supported by a number of autapomorphies of the adult bees at the wing base and venation, by the presence of Mycangiums and a specialized skinning extension in the larvae.

The scarab beetles include under the currently prevailing view, the Aphodiinae (including Aegialiinae and Aulonocneminae ), the Phaenomeridinae that Scarabaeinae that Orphninae that Melolonthinae that Rutelinae, the giant beetle ( Dynastinae ), the rose beetle ( Cetoniinae ), the Valginae, as well as the genus Acoma. The following is a complete list of sub-families:

• Aphodiinae Leach, 1815
• Scarabaeinae Latreille, 1802
• Pachypodinae Erichson, 1840
• Orphninae Erichson, 1847
• Allidiostomatinae Arrow, 1940
• Dynamopodinae Arrow, 1911
• Aclopinae Milne -Edwards, 1850
• Euchirinae Hope, 1840
• Phaenomeridinae Erichson, 1847
• Melolonthinae MacLeay, 1819
• Rutelinae MacLeay, 1819
• Giant beetle ( Dynastinae ) MacLeay, 1819
• Rose chafer ( Cetoniinae ) Leach, 1815
• Valginae Mulsant, 1842

Fossil evidence

As the oldest fossil Scarabaeide was long Aphodiites protogaeus Army, 1865. This was ever accepted by Crowson as the oldest representative of the Polyphaga. Recent studies have cast doubt on the assignment. The feature- poor fossil could therefore just as well to " every family oval beetle" belong. From the Jura there is only one China in newly discovered, well-preserved fossil, which was placed in a new (extinct ) Family Alloioscarabaeidae. The Scarabaeidae family itself is first occupied by Cretaceous finds. Further evidence from the Cretaceous amber of Lebanon are shown in Poinar, but have not been described to date scientifically. In addition, the family is represented by several genera in Baltic and Dominican amber (both from the Tertiary ).