''Cotinis mutabilis'', also known as the figeater beetle (also green fruit beetle or fig beetle), is a member of the scarab

beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

family. It belongs to the subfamily

Cetoniinae Flower chafers are a group of scarab beetles comprising the subfamily Cetoniinae. Many species are diurnal and visit flowers for pollen and nectar, or to browse on the petals. Some species also feed on fruit. The group is also called fruit and ...

, comprising a group of beetles commonly called flower chafers since many of them feed on pollen, nectar, or petals. Its habitat is primarily the southwestern United States (including

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

) and

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. Figeater beetles are often mistaken for green June beetles (''

Cotinis nitida ''Cotinis nitida'', commonly known as the green June beetle, June bug or June beetle, is a beetle of the family Scarabaeidae. It is found in the eastern United States and Canada, where it is most abundant in Southern United States, the South. It ...

'') and occasionally

Japanese beetle The Japanese beetle (''Popillia japonica'') is a species of Scarabaeidae, scarab beetle. Due to the presence of Predation, natural predators, the Japanese beetle is not considered a pest in its native Japan, but in North America and some region ...

s (''Popillia japonica''), which occur in the eastern US.

Life cycle

After mating, eggs are laid in decaying matter or compost piles, which provide sustenance for the emerging larvae. Figeater beetle

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e, commonly called "crawly backs", grow up to and are thick and white with a dark head. They have six small, ineffectual legs; to move, they roll onto their backs and propel themselves upside down, using the stiff dark hairs on their backs to gain traction. At rest, they curl into a firm ''C'' shape.

Pupation A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages th ...

occurs in the spring; adults emerge from July to September (varies with location). Adult figeater beetles grow to approximately . They are active during daylight hours, often congregating in the shade of trees near choice breeding grounds to find mates. They make a loud buzzing sound similar to that of

carpenter bee Carpenter bees are species in the genus ''Xylocopa'' of the subfamily Xylocopinae. The genus includes some 500 bees in 31 subgenera. The common name "carpenter bee" derives from their nesting behavior; nearly all species burrow into hard plant m ...

s, possibly because they do not need to open their

elytra An elytron (; ; : elytra, ) is a modified, hardened forewing of beetles (Coleoptera), though a few of the true bugs (Hemiptera) such as the family Schizopteridae are extremely similar; in true bugs, the forewings are called hemelytra (sometime ...

in order to fly, an ability shared with many other flower beetles.

Taxonomy

''C. mutabilis'' is often confused with the green June beetle (''

''). Both are members of the flower beetle subfamily (

), and are similar in appearance, but the green June beetle is smaller, and its range is in the eastern United States. The only possible crossover of both species is in Texas. They are also occasionally mistaken for

s (''Popillia japonica''), which occur in the eastern US.

Diet

The figeater beetle is native to moister areas of the American southwest, where its natural diet includes fruit from

cacti A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

and sap from desert trees. Their range has expanded considerably since the 1960s with the increasing availability of home gardens,

compost Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical, and biological properties. It is commonly prepared by Decomposition, decomposing plant and food waste, recycling organic materials, and man ...

piles, and organic

mulch A mulch is a layer of material applied to the surface of soil. Reasons for applying mulch include conservation of soil moisture, improving soil fertility, fertility and health of the soil, reducing Weed control, weed growth, and enhancing the v ...

. The larvae eat decomposing organic matter, such as that found in compost piles,

manure Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nut ...

piles, and organic mulch, and occasionally plant roots, such as the roots of grass in lawns. The adult's primary food has become fruit in gardens and orchards. They prefer sweet food, which includes the leaves, flowers, and saps of some plants and ripe or overripe fruit. Fruit with tough skins are too hard for them to bite through, so they most often eat softer-skinned fruit such as figs, peaches, grapes, pears, and tomatoes, among others. The beetles are particularly attracted to

ripening Ripening is a process in fruits that causes them to become more palatable. In general, fruit becomes sweeter, less green, and softer as it ripens. Even though the acidity of fruit increases as it ripens, the higher acidity level does not make t ...

and

fermenting Fermentation is a type of anaerobic metabolism which harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and reduced ...

fruit, which emit gases that lead the beetles to them, and to fruit that other animals or insects have already damaged. In most small gardens, the adult beetles are minor pests that do little damage; however, they can swarm on soft or damaged fruit and have been known to eat an entire garden grape or fig crop. They are not considered to be an important pest because they do not damage

lawn A lawn () is an area of soil-covered land planted with Poaceae, grasses and other durable plants such as clover lawn, clover which are maintained at a short height with a lawn mower (or sometimes grazing animals) and used for aesthetic an ...

s as

e and trees as much as June beetles or Japanese beetles. However, they have the potential to be considered of agricultural importance in the future.

Habitat & Distribution

Distribution of ''C. mutabilis'' ranges from the US to northern South America, and has been recorded in almost all of Mexico. They inhabit tropical and subtropical forests, oak forests, and cloud forests, as well as many different types of vegetation and land in urban areas between 0 - 2,700 meters above sea level.

References

{{Taxonbar, from=Q941636 Beetles of North America Cetoniinae Beetles described in 1883