Achelata
Infraorder of crustaceans
title: "Achelata" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["achelata", "arthropod-infraorders", "extant-late-jurassic-first-appearances"] description: "Infraorder of crustaceans" topic_path: "general/achelata" source: "https://en.wikipedia.org/wiki/Achelata" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary Infraorder of crustaceans ::
| fossil_range = | image = Haeckel Phyllosoma.jpg | image_caption = The phyllosoma larva is characteristic of the Achelata (drawing by Haeckel) | display_parents = 2 | taxon = Achelata | authority = Scholtz & Richter, 1995 | subdivision_ranks = Families | subdivision =
The Achelata is an infraorder of the decapod crustaceans, holding the spiny lobsters, slipper lobsters and their fossil relatives.
Description
The name "Achelata" derives from the fact that all the members of this group lack the chelae (claws) that are found on almost all other decapods (from the Ancient Greek , grc = "not", , grc = "claw"). They are further united by the great enlargement of the second antennae, by the special "phyllosoma" form of the larva, and by a number of other characters.
::figure[src="https://upload.wikimedia.org/wikipedia/commons/6/6b/Larva_de_phyllosoma.jpg" caption="Phyllosoma larva (micrograph)}}"] ::
Classification and fossil record
The infraorder Achelata belongs to the group Reptantia, which consists of the walking/crawling decapods (lobsters and crabs). The cladogram below shows Achelata's placement within the larger order Decapoda, from analysis by Wolfe et al., 2019.
Achelata contains the spiny lobsters (Palinuridae), the slipper lobsters (Scyllaridae) and the furry lobsters (Synaxidae, now usually included in Palinuridae), as well as two extinct families, Cancrinidae and Tricarinidae.
| direction = horizontal | align = left | header = Extant families of Achelata | width1 = 200 | image1 = Monaco.Musée océanographique089.jpg | caption1 = Palinurus elephas Palinuridae | width2 = 200 | image2 = Blind furry lobster.jpg | caption2 = Palinurellus gundlachi Palinuridae, formerly Synaxidae | width3 = 226 | image3 = Scyllarides latus.jpg | caption3 = Scyllarides latus Scyllaridae
Both Palinuridae and Scyllaridae have a fossil record extending back to the Cretaceous. The two fossil families contain a single genus each; Tricarina is known from a single Cretaceous fossil, while Cancrinos is known from the Jurassic and Cretaceous. One estimate of the divergence between Achelata and its closest relatives places it at about .
References
References
- (1995). "Phylogenetic systematics of the reptantian Decapoda (Crustacea, Malacostraca)". [[Zoological Journal of the Linnean Society]].
- (24 April 2019). "A phylogenomic framework, evolutionary timeline and genomic resources for comparative studies of decapod crustaceans". Proceedings of the Royal Society B.
- (2009). "Phylogenetic relationships between spiny, slipper and coral lobsters (Crustacea, Decapoda, Achelata)". [[Molecular Phylogenetics and Evolution]].
- (2009). "A classification of living and fossil genera of decapod crustaceans". [[Raffles Bulletin of Zoology]].
- (2006). "El Espinal, a new plattenkalk facies locality from the Lower Cretaceous Sierra Madre Formation, Chiapas, southeastern Mexico". [[Revista Mexicana de Ciencias Geológicas]].
- (2009). "Development in Mesozoic scyllarids and implications for the evolution of Achelata (Reptantia, Decapoda, Crustacea)". [[Palaeodiversity]].
- (2007). "A new family, genus, and species of lobster (Decapoda: Achelata) from the Gadvan Formation (Early Cretaceous) of Iran". [[Journal of Paleontology]].
- (2009). "The Timetree of Life". [[Oxford University Press]].
::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::