''Sternotomis callais'' (African longhorn beetle) is a species of
beetle in the family
Cerambycidae. It was described by
Léon Fairmaire
Léon Marc Herminie Fairmaire (29 June 1820 – 1 April 1906) was a French entomologist.
A specialist in Coleoptera he assembled an immense collection comparable with that of Pierre François Marie Auguste Dejean (1780-1845). This is in the Mus� ...
in 1891. It is known from
Cameroon, the
Republic of the Congo
The Republic of the Congo (french: République du Congo, ln, Republíki ya Kongó), also known as Congo-Brazzaville, the Congo Republic or simply either Congo or the Congo, is a country located in the western coast of Central Africa to the w ...
, the
Democratic Republic of the Congo,
Equatorial Guinea
Equatorial Guinea ( es, Guinea Ecuatorial; french: Guinée équatoriale; pt, Guiné Equatorial), officially the Republic of Equatorial Guinea ( es, link=no, República de Guinea Ecuatorial, french: link=no, République de Guinée équatoria ...
, and
Angola. It feeds on ''
Coffea liberica var. dewevrei''.
Brilliant green coloration
The scales on the African longhorn beetle exhibit a brilliant green color due to a
photonic crystal-like periodic cuticle network, and the three-dimensional network of the cuticle was found to be modelled appropriately by the I-WP photonic crystal.
Although described mathematically in 1970, this is the first time this kind of photonic crystal structure has been observed in nature.
The I-WP-type minimal surface was mathematically found by Schoen in 1970, was named "I-graph-Wrapped Package graph surface" because it reminded Schoen of the arrangement of string on a simply wrapped package.
The wavelength range of the green color corresponds to the frequency of the photonic band gap.
References
Sternotomini
Beetles described in 1891
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