''Chrysina limbata'' is a species of scarab beetle found in the tropical rainforests of Central America, including Costa Rica, and Mexico. It is in the genus '' Chrysina'', in the subfamily

Rutelinae Rutelinae or shining leaf chafers is a subfamily of the scarab beetles (family Scarabaeidae). It is a very diverse group; distributed over most of the world, it contains some 200 genera with over 4,000 described species in 7 tribes. A few recen ...

(shining leaf chafers). It is notable for its metallic reflective silver color.

Taxonomy

''Chrysina limbata'' was described in 1894 by zoologists

Walter Rothschild Lionel Walter Rothschild, 2nd Baron Rothschild, Baron de Rothschild, (8 February 1868 – 27 August 1937) was a British banker, politician, zoologist and soldier, who was a member of the Rothschild family. As a Zionist leader, he was presen ...

and Karl Jordan, initially as ''Plusiotis limbata'' - ''Plusiotis'' being a synonym of ''Chrysina.'' ''C. limbata'' is in the superfamily

Scarabaeoidea Scarabaeoidea is a superfamily of beetles, the only subgroup of the infraorder Scarabaeiformia. Around 35,000 species are placed in this superfamily and some 200 new species are described each year. Its constituent families are also undergoing r ...

, family

Scarabaeidae The family Scarabaeidae, as currently defined, consists of over 30,000 species of beetles worldwide; they are often called scarabs or scarab beetles. The classification of this family has undergone significant change in recent years. Several sub ...

, subfamily

and tribe

Rutelini Rutelini is a tribe of shining leaf chafers in the family Scarabaeidae The family Scarabaeidae, as currently defined, consists of over 30,000 species of beetles worldwide; they are often called scarabs or scarab beetles. The classification of ...

Description

''C. limbata'' measures between 25 and 35 mm in length. They have a reflective silver metallic appearance which is achieved through

thin film interference Thin-film interference is a natural phenomenon in which light waves reflected by the upper and lower boundaries of a thin film interfere with one another, either enhancing or reducing the reflected light. When the thickness of the film is an ...

within layers of

chitin Chitin ( C8 H13 O5 N)n ( ) is a long-chain polymer of ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is probably the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chit ...

. These layers of the chitin coating are chirped (in layers of differing thicknesses), forming a complex multilayer as each layer decreases in depth; as the thickness changes, so too does the optical path-length. Each chirped layer is tuned to a different wavelength of light. The multilayer found on ''C. limbata'' reflects close to 97% of light across the visible wavelength range. Physicist William E. Vargas believes that the metallic appearance may act like water, appearing only as a bright spot to predators. The rain forest of

Costa Rica Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the no ...

where ''C. limbata'' lives has water suspended from leaves at ground level. Light is refracted in different directions, and it allows metallic beetles to fool predators.

Life history

Like all beetles, scarabs go through a

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...

. The life cycle begins when the female lays an egg, which becomes a larva, then a c-shaped pupa, which becomes an adult. The scarab beetles lay their eggs in the ground or in decomposing materials. Larvae feed on plant roots or rotting matter.

Distribution

''Chrysina limbata'' is found in tropical forests of Costa Rica, Central America and Southeast Mexico, especially in the mountain ranges 600 meters above sea level. In 2007 ''

National Geographic Magazine ''National Geographic'' (formerly the ''National Geographic Magazine'', sometimes branded as NAT GEO) is a popular American monthly magazine published by National Geographic Partners. Known for its photojournalism, it is one of the most widely ...

'' reported that certain varieties of related beetles could be sold for as much as $500, but loss of habitat is a greater threat to ''Chrysina'' species than collectors.

References

{{Taxonbar, from=Q14899251 Rutelinae Beetles of Central America