Megalyroidea is a small

hymenoptera Hymenoptera is a large order (biology), order of insects, comprising the sawfly, sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are Par ...

n superfamily of wasps that includes a single family, Megalyridae, with eight extant genera (plus around a dozen extinct ones) and 49 described species. Modern megalyrids are found primarily in the southern hemisphere, though fossils have only been found in the northern hemisphere. The most abundant and species-rich megalyrid fauna is in

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. Another peak of diversity appears to be in the

relict A relict is a surviving remnant of a natural phenomenon. Biology A relict (or relic) is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas. Geology and geomorphology In geology, a r ...

forests of

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

, but most of these species are still undescribed. Historically, there has been much confusion about the definition of this family. Species now placed in Megalyridae have in the past been classified into as many as six other families (

Braconidae The Braconidae are a family of parasitoid wasps. After the closely related Ichneumonidae, braconids make up the second-largest family in the order Hymenoptera, with about 17,000 recognized species and many thousands more undescribed. One analysis ...

Evaniidae Evaniidae is a family of parasitoid wasps also known as ensign wasps, nightshade wasps, hatchet wasps, or cockroach egg parasitoid wasps. They number around 20 extant genera containing over 400 described species, and are found all over the world e ...

Ichneumonidae The Ichneumonidae, also known as the ichneumon wasps, Darwin wasps, or ichneumonids, are a family (biology), family of parasitoid wasps of the insect order Hymenoptera. They are one of the most diverse groups within the Hymenoptera with roughly 2 ...

, and

Stephanidae The Stephanidae, sometimes called crown wasps, are a family of parasitoid wasps. They are the only living members of the superfamily Stephanoidea. Stephanidae has at least 345 living species in 11 genera. The family is considered cosmopolitan in ...

, as well as Dinapsidae and

Maimetshidae Maimetshidae is an extinct family of wasps, known from the Cretaceous period.M. S. Engel. 2016A new genus and species of maimetshid wasps in Lebanese Early Cretaceous amber (Hymenoptera: Maimetshidae).''Novitates Paleoentomologicae'' 18:1-14 While ...

, with Dinapsidae now considered to be within the Megalyridae. Maimetshidae is no longer considered closely related to Megalyridae, and has been included in Trigonaloidea with

Trigonalidae Trigonalidae (the spelling Trigonalyidae is incorrect under Article 29.5 of the ICZN,ICZN Code
29.5. Maintena ...

. The oldest fossils confidently identifiable as Megalyrids date to the

Early Cretaceous The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Pro ...

. The best defining feature, unique to the family, is the mesothoracic

spiracle Spiracle or spiraculum may refer to: * Spiracle (arthropods), opening in the exoskeletons of some arthropods * Spiracle (vertebrates), openings on the surface of some vertebrates * Spiraculum, a genus of land snails in family Cyclophoridae Cycl ...

has moved, and is actually located in the upper corner of 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 ...

, though this is a fairly obscure feature to see. Perhaps the most useful visible character is that the base of the antenna fits into a wide, concave groove below the eye, though a few other wasp families exhibit this trait. Females of '' Megalyra'' have ovipositors ranging from five to eight times their body length, but this is not true of the other genera. The largest known megalyrid is the female of the

n '' Megalyra shuckardi'', with a body length of and

ovipositor The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typical ...

length of . The smallest known megalyrid is the

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 ...

ian '' Cryptalyra plaumanni'', with a body length of and ovipositor long. Megalyrid wasps are thought to be

idiobiont In evolutionary ecology, a parasitoid is an organism that lives in close association with its host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionary strategies within parasiti ...

endoparasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionary strategies within parasitis ...

s of concealed insect larvae. One Australian species, '' Megalyra troglodytes'', attacks the larvae of '' Arpactophilus mimi'', a mud-nesting crabronid wasp. Oviposition habits of Megalyridae are regarded as quite primitive, with field observations suggesting they simply poke their ovipositors into pre-existing cavities, holes, or cracks, rather than drilling into the substrate as in other

Apocrita Apocrita is a suborder of insects in the order Hymenoptera. It includes wasps, bees, and ants, and consists of many families. It contains the most advanced hymenopterans and is distinguished from Symphyta by the narrow "waist" ( petiole) formed ...

Genera

Extant genera * '' Carminator'' East Asia, Southeast Asia, New Guinea * '' Cryptalyra'' Northern South America * '' Dinapsis'' Africa, Madagascar * '' Ettchellsia'' Southeast Asia * '' Megalyra'' Australia, New Guinea, Southeast Asia * '' Megalyridea'' South Africa * '' Neodinapsis'' Chile * ''

Rigel Rigel is a blue supergiant star in the constellation of Orion. It has the Bayer designation β Orionis, which is Latinized to Beta Orionis and abbreviated Beta Ori or β Ori. Rigel is the brightest and most massive componentand ...

'' Chile Extinct genera * †'' Megalava'' Perrichot 2009 Spanish amber, Early Cretaceous (

Albian The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0.9 M ...

) * †'' Megazar'' Perrichot 2009 Charentese amber, Late Cretaceous (

Cenomanian The Cenomanian is, in the ICS' geological timescale, the oldest or earliest age of the Late Cretaceous Epoch or the lowest stage of the Upper Cretaceous Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in the s ...

) * †'' Valaa'' Perrichot 2009 Spanish amber, Early Cretaceous (Albian) * †'' Prodinapsis'' Brues 1923

Oise amber Oise ( ; ; pcd, Oése) is a department in the north of France. It is named after the river Oise. Inhabitants of the department are called ''Oisiens'' () or ''Isariens'', after the Latin name for the river, Isara. It had a population of 829,419 ...

, France,

Bitterfeld amber The Baltic region is home to the largest known deposit of amber, called Baltic amber or succinite. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that these forests created more than 1 ...

, Germany,

Rovno amber Rivne amber, occasionally called Ukrainian amber, is amber found in the Rivne Oblast and surrounding regions of Ukraine and Belarus. The amber is dated between Late Eocene and Early Miocene, and suggested to be contemporaneous to Baltic amber. ...

, Ukraine,

Baltic amber The Baltic region is home to the largest known deposit of amber, called Baltic amber or succinite. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that these forests created more than 1 ...

Eocene The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...

References

Cited texts

* Rasnitsyn, A.P. & Brothers, D.J. 2009. New genera and species of Maimetshidae (Hymenoptera: Stephanoidea s.l.) from the Turonian of Botswana, with comments on the status of the family. ''

African Invertebrates ''African Invertebrates'' is a peer-reviewed open access scientific journal that covers the taxonomy, systematics, biogeography, ecology, conservation, and palaeontology of Afrotropical invertebrates, whether terrestrial, freshwater, or marine. I ...

'' 50 (1): 191-20
Abstract
https://web.archive.org/web/20110718201933/http://fossilinsects.net/pdfs/rasnitsyn_brothers_2009_AfrInv_50_1_MaimetshidaeTuronianOrapa_LR.pdf PDF]

External links

Tree of Life Megalyridae
{{Taxonbar, from=Q140741 Parasitica Apocrita families