The Glypheoidea is a group of lobster

Lobster

Clawed lobsters comprise a family of large marine crustaceans. Highly prized as seafood, lobsters are economically important, and are often one of the most profitable commodities in coastal areas they populate.Though several groups of crustaceans are known as lobsters, the clawed lobsters are most...

-like decapod

Decapoda

The decapods or Decapoda are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crayfish, crabs, lobsters, prawns and shrimp. Most decapods are scavengers. It is estimated that the order contains nearly 15,000 species in around 2,700 genera, with...

 crustacean

Crustacean

Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s which forms an important part of fossil faunas, such as the Solnhofen limestone

Solnhofen limestone

The Solnhofen Plattenkalk is a Jurassic Konservat-Lagerstätte that preserves a rare assemblage of fossilized organisms, including highly detailed imprints of soft bodied organisms such as sea jellies...

. These fossils included taxa such as Glyphea (from which the group takes its name), and Mecochirus, mostly with elongated (often semichelate) chelipeds. This group of decapods is a good example of a living fossil

Living fossil

Living fossil is an informal term for any living species which appears similar to a species otherwise only known from fossils and which has no close living relatives, or a group of organisms which have long fossil records...

, or a lazarus taxon

Lazarus taxon

In paleontology, a Lazarus taxon is a taxon that disappears from one or more periods of the fossil record, only to appear again later. The term refers to the account in the Gospel of John, in which Jesus raised Lazarus from the dead...

, since until their discovery in the 1970s, the group was considered to have become extinct in the Eocene

Eocene

The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

. The superfamily

Taxonomic rank

In biological classification, rank is the level in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, and class. Each rank subsumes under it a number of less general categories...

 Glypheoidea comprises five families. The two extant species, Neoglyphea inopinata and Laurentaeglyphea neocaledonica, are both in the Glypheidae.

The Glypheoidea was originally considered to be a purely fossil group. That opinion had to be altered when a single male specimen was discovered in the collections of the Smithsonian Institution

Smithsonian Institution

The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...

 in 1975. It had been caught off the Philippines

Philippines

The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...

 in 1908 and preserved, without its full significance being realised. Over sixty years later, the specimen was rediscovered, and described by two French scientists as a new genus and species, Neoglyphea inopinata in 1975, meaning "unexpected new Glyphea". More individuals were caught on subsequent expeditions in 1976, 1980 and 1985, allowing for a complete description. A second species was discovered in the Coral Sea

Coral Sea

The Coral Sea is a marginal sea off the northeast coast of Australia. It is bounded in the west by the east coast of Queensland, thereby including the Great Barrier Reef, in the east by Vanuatu and by New Caledonia, and in the north approximately by the southern extremity of the Solomon Islands...

, near New Caledonia

New Caledonia

New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

, in 2005. First described as Neoglyphea neocaledonica, in 2006, it has been transferred to a new genus Laurentaeglyphea, much closer to fossil forms.

Classification

Five families are recognised, containing a total of 21 genera, all but two of which are extinct:

• Chimaerastacidae †

Chimaerastacus †

• Glypheidae

Cedrillosa †

Glyphea †

Laurentaeglyphea

Neoglyphea

Paralitogaster †

Squamosoglyphea †

Trachysoma †

• Mecochiridae †

Huhatanka †

Jabaloya †

Mecochirus

Mecochirus

Mecochirus is an extinct genus of lobster-like decapod crustaceans, containing 17 species....

†

Meyeria †

Preatya †

Pseudoglyphea †

Selenisca †

• Pemphicidae †

Pemphix †

Pseudopemphix †

Sinopemphix †

• Platychelidae †

Glaessnericaris †

Platychela †

Platypleon †