Derivation of scientific name
Garden fruit chafers belong to the order Coleoptera, which is derived from the Greek words koelos, which means sheath or shield, and ptera, meaning wings. The name refers to the hard shield formed by the wings that covers much of a beetle’s body.
Other common names
Brown fruit chafer, yellow fruit chafer (Eng.); vrugtetor (Afr.).
Introduction
Coleoptera is the largest and most diverse group in the entire animal kingdom, with over 370 000 species worldwide. They are distinguished from other insects by a very hard pair of wings, which cover most of the abdomen. The family Scarabaeidae consists of agricultural and horticultural pests, with dung beetles as the beneficial species. Within this family, the genus Pachnoda has about 108 species occurring all over Africa, and stretching into southern Europe and the Arabic peninsula (WAZA 2015). Adults can reach a length of 24 mm.
They have well developed biting or chewing mouthparts, which are suited to feeding on plant materials, mainly fruits and flowers. P. sinuata (garden fruit chafer) is a yellowish beetle with dark-green coloration on the dorsal surface of the body. These colours help deter predators from eating them.
How to recognise a garden fruit chafer
The garden fruit chafer is a medium-sized beetle about 25 mm in length. These beetles have a slightly flat, robust body with a yellow colour on the ventral side of the body and dark brown on the dorsal surface of the body. The coloration is also broken by yellow spots and a transverse yellow line across the rear of the forewings. The head is dark brownish with two long yellowish patches on each side of it and two oval white spots above the eyes (Prins 1984).
Distribution
In South Africa, Peringuey (1907) documented that P. sinuata is widely represented in the Western Cape, especially in the orchard areas from Worcester to Somerset West, and has also been collected at Elands Bay. Meanwhile a study by Donaldson (1979), recorded the species to be common around Milnerton, Pinelands, Beaufort West and even at Kuruman (Prins 1984).
Habitat
Garden fruit chafers are commonly found in orchards and gardens.
Food
The adults feed mainly on fruits and flowers. They feed by extracting the juices from the fruits, which is why they are known as fruit chafers. Fruit chafers also feed on exotic plants such as roses and camellias, as well as indigenous plants like acacias. The larvae feed on organic material in compost heaps and other decaying organic matter.
SEX and LIFE CYCLES
The entire lifespan of a beetle consists of four stages; egg–larva–pupa and adult stages. P. sinuata adults are commonly found in compost heaps, where they lay their eggs. Larvae, which look like curved caterpillars or worms, feed on plant materials in compost heaps or other suitable decaying organic matter, and when fully matured, they construct hard, oval, clay shells. The pupae develop inside these large, oval, protective clay shells.
Friends and Foes
This species is a popular prey species for many species of bird, such as Red-winged Starlings and Hadeda Ibises (Wikipedia).
Smart Strategies
Their upper wings are made of chitin, which is rigid and tough and it protects and shields the softer, thinner, hind wings. Because the wings are hard, they are difficult to crack, which provides good protection from certain enemies. They also have variable colours that camouflage their presence.
People and I
Fruit chafers are familiar garden pests. They affect plants by chewing on the fleshy foliage and causing irregular holes, and they bore into the soft, ripe fruit to extract the juices, an action that spoils the fruits. This makes them unpopular amongst gardeners and farmers. Some of the flowers affected include roses, proteas, carnations and dahlias, and fruits affected include grapes.
Conservation status and what the future holds
This species is not yet assessed for the International Union for Conservation of Nature Red List, and it is not listed on the Convention on International Trade in Endangered Species of Wild Fauna and Flora. It is, however, common and relatively widespread, and is currently unlikely to be threatened.
Relatives
The family Scarabaeidae is not only comprised of the chafers, but contains species such as dung beetles as well. P. sinuata has several subspecies, including P. s. calceata (Harold, 1878), P. s. flaviventris (Gory & Percheron, 1833), P. s. machadoi (Rigout, 1989) and P. s. nicolae (Rigout, 1987).
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Family: Scarabaeidae
Genus: Pachnoda
Species: P. sinuata (Fabricius, 1775)
References and further reading
- Picker, M., Griffiths, C.L. & Weaving, A. 2004. Field guide to insects of South Africa. Struik Nature, Cape Town.
- Wikipedia. http://en.wikipedia.org/wiki/Pachnoda_sinuata [Accessed on 11 June 2015].
- World Association of Zoos and Aquariums. WAZA Available at http://www.waza.org/en/zoo/choose-a-species/invertebrates/insects-and-millipedes/pachnoda-sinuata [Accessed on 11 June 2015].
- Prins, A.J. (1984). Morphological and biological notes on some South African arthropods associated with decaying organic matter. Part 3. The families Dermestidae, Cantharidae, Melyridae, Tenebrionidae and Scarabaeidae. Annals of the South African Museum: 203–304. http://www.biodiversitylibrary.org/part/74591.
Author: Given Leballo
SANBI, Biosystematics
July 2015