Ascothoracida

Ascothoracida
A member of the Dendrogaster genus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Thecostraca
Subclass: Ascothoracida
Lacaze-Duthiers, 1880 [1]
Orders and families [2]

Dendrogastrida Grygier, 1987

Laurida Grygier, 1987

Ascothoracida is a small group of parasitic marine crustaceans, comprising around 100 species and divided into Dendrogastrida and Laurida.[3] They are found throughout the world on cnidarians and echinoderms.[4] Dendrogastrida are parasites on echinoderms, and Laurida are parasites on cnidarians, except from the species Waginella Grygier, which is also a parasite on echinoderms (crinoids). Piercing and sucking mouthparts are used for feeding, and more advanced forms also absorbs nutrients through a modified integument of the carapace. More basal forms are ectoparasitic, but most genera are meso- and endoparasitic. The sexes are separate, except from secondary hermaphroditic species of the Petrarcidae. In many species the larger female often have smaller males living inside her mantle cavity.[5][6]

Ascothoracida was previously ranked as an order within the infraclass Cirripedia (barnacles), but now both Ascothoracida and Cirripedia are considered separate subclasses. Those two subclasses, along with Facetotecta, make up the class Thecostraca.[2][7][8]

The thorax of Ascothoracida species has six pair of biramous appendages, while the abdomen has four segments and a terminal telson with a caudal furca.[9] This arrangement is similar to that seen in copepods.[9] In addition, there is a bivalved carapace, which is expanded in females.[9]

  1. ^ "Ascothoracida Lacaze-Duthiers, 1880". Integrated Taxonomic Information System. Retrieved December 8, 2010.
  2. ^ a b Cite error: The named reference M&D was invoked but never defined (see the help page).
  3. ^ Paul Schmid-Hempel (2011). "The diversity and natural history of parasites". Evolutionary Parasitology: the Integrated Study of Infections, Immunology, Ecology, and Genetics. Oxford University Press. pp. 18–51. ISBN 978-0-19-922949-9.
  4. ^ J. K. Lowry (October 2, 1999). "Ascothoracida (Thecostraca, Maxillipoda)". Crustacea, the Higher Taxa: Description, Identification, and Information Retrieval. Australian Museum. Archived from the original on February 24, 2012. Retrieved December 31, 2009.
  5. ^ Parasitic Crustacea: State of Knowledge and Future Trends
  6. ^ Atlas of Crustacean Larvae
  7. ^ Cite error: The named reference Chan2021 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference worms was invoked but never defined (see the help page).
  9. ^ a b c D. R. Khanna (2004). "Segmentation in arthropods". Biology of Arthropoda. Discovery Publishing House. pp. 316–394. ISBN 978-81-7141-897-8.