Actaeon beetle (''Megasoma actaeon'') is a
rhinoceros beetle
Dynastinae or rhinoceros beetles are a subfamily of the scarab beetle family (Scarabaeidae). Other common names – some for particular groups of rhinoceros beetles – include Hercules beetles, unicorn beetles or horn beetles. Over 1 ...
of 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 this family has undergone significant change in recent years. Several sub ...
.
Etymology
The species name ''actaeon'' derives from the name
Actaeon
Actaeon (; grc, Ἀκταίων ''Aktaion''), in Greek mythology, son of the priestly herdsman Aristaeus and Autonoe in Boeotia, was a famous Theban hero. Like Achilles in a later generation, he was trained by the centaur Chiron.
He fell to ...
of a famous
Theban hero, son of the priestly herdsman
Aristaeus
A minor god in Greek mythology, attested mainly by Athenian writers, Aristaeus (; ''Aristaios'' (Aristaîos); lit. “Most Excellent, Most Useful”), was the culture hero credited with the discovery of many useful arts, including bee-keeping; ...
and
Autonoe in
Boeotia
Boeotia ( ), sometimes Latinized as Boiotia or Beotia ( el, Βοιωτία; modern: ; ancient: ), formerly known as Cadmeis, is one of the regional units of Greece. It is part of the region of Central Greece. Its capital is Livadeia, and its lar ...
, trained by the centaur
Chiron
In Greek mythology, Chiron ( ; also Cheiron or Kheiron; ) was held to be the superlative centaur amongst his brethren since he was called the "wisest and justest of all the centaurs".
Biography
Chiron was notable throughout Greek mythology ...
.
Description
Actaeon beetle is one of the largest of all
beetle
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...
s, measuring up to across, with a body length of about . The males can grow to be 13 cm (5.4 in) long by 4 cm (1.6 in) thick .
The dorsal surfaces are glabrous (bald), matte or shiny black. The legs are powerful, with large tarsal claws. Males have appendages resembling horns on the
pronotum
The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on ea ...
and on the head. The two parallel horns on the
pronotum
The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on ea ...
are short, acute and forward pointing, while a much longer horn with a small tooth is present on the head. In the females the
pronotum
The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on ea ...
and the
elytra
An elytron (; ; , ) 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 (sometimes alterna ...
are rugose and the horns are missing.
[
]
Life cycle
Females lay eggs into soil at eclosion
A pupa ( la, pupa, "doll"; plural: ''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 ...
and eggs develop in about 9 months. Larval development and pupation
A pupa ( la, pupa, "doll"; plural: ''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 thei ...
takes in total almost 3 years. Larvae at the 3rd instar
An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or ass ...
can reach the weight of 200 grams, the highest weight among insects. Life expectancy of adults in captivity reaches about 100–150 days. The heaviest Actaeon ever recorded was found in the northern regions of South America weighed 228 grams (8.04 oz) in 2009 nearly equivalent to a female rat. This not only makes it the heaviest beetle but the heaviest insect of any kind.
Distribution
This species can be found in South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
, particularly in Bolivia
, image_flag = Bandera de Bolivia (Estado).svg
, flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center
, flag_alt2 = 7 × 7 square p ...
, Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
, Colombia
Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...
, Ecuador
Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...
, México
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
, French Guiana
French Guiana ( or ; french: link=no, Guyane ; gcr, label=French Guianese Creole, Lagwiyann ) is an overseas departments and regions of France, overseas department/region and single territorial collectivity of France on the northern Atlantic ...
, Guyana
Guyana ( or ), officially the Cooperative Republic of Guyana, is a country on the northern mainland of South America. Guyana is an indigenous word which means "Land of Many Waters". The capital city is Georgetown. Guyana is bordered by the ...
, Panama
Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...
, Peru
, image_flag = Flag of Peru.svg
, image_coat = Escudo nacional del Perú.svg
, other_symbol = Great Seal of the State
, other_symbol_type = Seal (emblem), National seal
, national_motto = "Fi ...
, Suriname
Suriname (; srn, Sranankondre or ), officially the Republic of Suriname ( nl, Republiek Suriname , srn, Ripolik fu Sranan), is a country on the northeastern Atlantic coast of South America. It is bordered by the Atlantic Ocean to the north ...
, and Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
.[
]
See also
* List of largest insects
Insects, which are a type of arthropod, are the most numerous group of multicellular organisms on the planet, with over a million species identified so far. The title of heaviest insect in the world has many contenders, the most frequently crowne ...
References
Photos Elephant beetle ''Megasoma actaeon''
External links
{{Taxonbar, from=Q644737
Dynastinae
Beetles of South America
Arthropods of Colombia
Beetles described in 1758
Taxa named by Carl Linnaeus