Cetonia aurata (Linnaeus, 1761)
The typical subspecies C. a. aurata (Linnaeus, 1761) occurs throughout southern and central Europe north to southern Scandinavia and the U.K. and east to Turkey and Ukraine. At least 6 subspecies have been described, the distribution of which is sometimes sympatric with the typical subspecies, and there are many named colour varieties; almost 40 in France alone. Subspecies include:
C. a. sicula Aliquo, 1983 from Sicily.
C.a. jingkelii Flutsch & Tauzin, 2009 from China.
C. a. pallida (Drury, 1773) from the eastern Mediterranean, Turkey and Asia Minor.
C. a. pisana Heer, 1841 from Western Europe, with many named colour varieties.
C. a. pokornyi Rataj, 2000 from Western Siberia.
C. a. vridiventris Reitter, 1896 from Kazakhstan and Southern Siberia.
The nominate subspecies occurs locally and sometimes commonly in southern England and south Wales, becoming less common in the midlands and rare in northern England and southern Scotland.
A black form occurs in the west of Cornwall and the Scilly Isles. Numbers tend to fluctuate, typically they are common for a year or two and then scarce for a few years. The adults become active in May, flying in the afternoon and evening, and feeding upon pollen and nectar in a wide range of flowers including umbels, honeysuckle and viburnum but they seem particularly fond of Elder and roses. They may sometimes be seen in numbers flying around the tops of small trees and shrubs towards the evening. On the continent they sometimes feed on soft fruits including peaches and apricots, chewing holes into the fruit and feeding under the skin, and in some years are so serious as pests that baited traps are available to help control their numbers. Mating occurs in the spring and eggs are laid among compost or in decaying trees during June and July, after which the females die. Adults generally persist into
July or occasionally later. The larvae grow quickly and will moult twice before the winter; they take two years to become fully grown and will pupate from June to August in a subterranean cell in humus-rich soil or among compost or tree-trunk detritus. Larvae have been found in plant pots, feeding on the compost etc. but apparently not harming the plants. Adults eclose from August and a few become active in the autumn but the majority remain in the pupal cell until the following spring, emerging when the temperature reaches about 15°C. The larvae are typically scarabaeiod; C-shaped with a firm and soft body, small head and large hind body and tiny legs, they are distinguished from other U.K. chafer larvae in having pink head and legs and transverse rows of reddish hairs along the body. They reach 3.5cm when fully grown. They often occur in large numbers among organic matter and are beneficial in breaking down compost and decaying wood; the pupae may be found in the same habitats, encrusted in a covering of compost or woody material. Unlike the larvae of some chafers they do not feed on roots.
Among the U.K. fauna the adults can only be confused with the superficially similar Protaetia metallica (Herbst, 1782), formerly included in Cetonia. In that species the apical elytral margin is straight, or very nearly so, while in Cetonia it is distinctly sinuate before the suture. 14-21mm. Typically bright metallic green with irregular white transverse lines or marks to the elytra, the underside is brilliant coppery or bronze. In the U.K. the colour tends to be rather stable but coppery, bluish or reddish specimens occasionally occur. The mesosternal process is rounded, very finely punctured and has a fine transverse suture whereas in Protaetia it is truncate, distinctly punctured and has a well impressed suture before the apical dilation. In male Cetonia the abdomen is depressed along the centre and the terminal ventrite has a series of transverse lines each side of the centre; in the female these lines are continuous across the ventrite and the abdomen is not depressed medially.
CETONIA Fabricius, 1775
This is a genus of about 40 species of Palaearctic, Asian and African chafers included in 3 subgenera. They are generally bright metallic green, red or bronze and some species have suffered from a proliferation of named colour varieties and subspecies; in some areas a single species will occur in many named forms which, together with the massive amount of synonymy etc. associated with the group, can make a study of the genus very difficult. They are medium sized chafers, generally between 15 and 25mm, and of a characteristic appearance although some other genera e.g. Protaetia Burmeister, 1842 are closely similar. All are of a broad and dorsally flattened appearance, glabrous or only scantily pubescent and lack any sexually dimorphic head or pronotal modifications. The antennal insertions are visible from above and the clypeus is constricted in front of the eyes and covers the labrum and mandibles. The scutellum is very large and elongate-triangular. The elytra are deeply constricted laterally in the anterior third which allows the wings to be extended rapidly while the elytra are closed, and the mesothoracic epimera are visible from above along the anterior margin of the elytra. The pygidium is exposed although not generally visible from above. The legs are long and robust with the tibiae variously toothed, the pro-tibiae strongly so, and with strong spines on the inner apical angle. The tarsi are long with all the segments expanded apically, not sexually dimorphic, and with small, paired claws which are simple and equal in length. They are mostly thermophilic, diurnal and strong fliers, often aggregating or flying in numbers around flowers and shrubs. Adults feed on pollen, nectar and some consume petals or foliage and may cause damage to commercially produced plants. The larvae feed among organic matter or in decaying trees and some are associated with ants, both as larvae and adults. Most species are widespread although some have a restricted distribution or are island endemics e.g. C. viridescens Reitter, 1891 occurs in Syria and Iran while C. carthami Curtis, 1913 is found on Corsica, and C. cypriaca Alexis, 1994 on Cyprus.
Less metallic general appearance.
Generally northern distribution.
Elytral apex at most very weakly sinuate before suture (Fig. a)
Fig. a) Elytral apex in Protaetia metallica (left) and C. aurata (right).