''Megascolia procer'', the giant scoliid wasp, is a solitary
wasp
A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder ...
in the family
Scoliidae found across Asia. It is one of the largest wasps in the world, with a wingspan of .
[ Measurement scale on Figure 1.]
Description

''M. procer'' is a large tropical wasp with a body length of .
[ The body is primarily black with yellowish markings on the front and vertex of the head, pronotum, scutellum, metanotum, medial spot on the first gastral tergite, and a pair of anterolateral spots on the third gastal tergite. The wings are brown with blue iridescent reflections.][ This structural coloration is because the wing is made of ]chitin
Chitin (carbon, C8hydrogen, H13oxygen, O5nitrogen, N)n ( ) is a long-chain polymer of N-Acetylglucosamine, ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is the second most abundant polysaccharide in nature (behind only cell ...
, made dark with melanin
Melanin (; ) is a family of biomolecules organized as oligomers or polymers, which among other functions provide the pigments of many organisms. Melanin pigments are produced in a specialized group of cells known as melanocytes.
There are ...
, and covered with a transparent overlayer thick that acts as an interference thin film.
Distribution
The nominate subspecies has a broad range across the continent of Asia, including records in Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...
, Malaysia
Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...
, Singapore
Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...
, Malaya, Thailand
Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...
, Myanmar
Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...
, and India
India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
.[ There are also subspecies found in ]Sumatra
Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi. ...
, Java
Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...
, and Borneo
Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...
.
Life cycle
The species is a parasitoid
In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...
of the scarabaeid Atlas beetle, '' Chalcosoma atlas''. The wasp paralyzes a beetle grub with its sting, then lays an egg on it and buries it in an underground cell. When the wasp larva hatches, it consumes its still-living host before pupating inside its remains.
Subspecies
There are four subspecies of ''M. procer'':
* '' Megascolia procer procer'' (Illiger, 1802)
* '' Megascolia procer bimaculata'' (Gribodo, 1893)
* '' Megascolia procer javanensis'' Betrem, 1964
* '' Megascolia procer nigriventris'' (Mantero, 1903)
See also
* List of largest insects
References
{{Taxonbar, from=Q3022446
Scoliidae
Hymenoptera of Asia
Insects of Indonesia
Insects of Java
Insects of Borneo
Insects described in 1802