go to the Tree of Life home page
advanced
Complete
This is an archived version of a Tree of Life page. For up-to-date information, please refer to the current version of this page.

Myopsida Naef, 1916

Michael Vecchione and Richard E. Young
taxon links [down<--]Decapodiformes [up-->]Australiteuthidae [up-->]Loliginidae Interpreting the tree
close box

This tree diagram shows the relationships between several groups of organisms.

The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life. The basal branching point in the tree represents the ancestor of the other groups in the tree. This ancestor diversified over time into several descendent subgroups, which are represented as internal nodes and terminal taxa to the right.

example of a tree diagram

You can click on the root to travel down the Tree of Life all the way to the root of all Life, and you can click on the names of descendent subgroups to travel up the Tree of Life all the way to individual species.

For more information on ToL tree formatting, please see Interpreting the Tree or Classification. To learn more about phylogenetic trees, please visit our Phylogenetic Biology pages.

close box
Containing group: Decapodiformes

Introduction

Myopsid squids are, neritic, often in very shallow water, or upper slope demersal species. Many species are strong swimmers, occur in large schools and are fished commercially for food. The Loliginidae contains many species some of which reach a rather large size (at least 90 cm ML in Loligo forbesii) but those in Pickfordiateuthis, are dwarf species where males may mature at less than 14 mm ML (Brachoniecki, 1996). The Australiteuthidae contains a single species that is also a dwarf with males that mature as small as 17 mm ML (Lu, 2005).

Diagnosis

A decapodiform ...

Characteristics

  1. Arms
    1. Suckers of arms (and tentacles) with circularis muscles (unknown in Australiteuthidae).
  2. Tentacles
    1. Club without proximal (= carpal) locking-apparatus.
    2. Figure. Oral view of the tentacular club of Loligo plei, 105 mm ML, preserved. Photograph by R. Young.

  3. Buccal crown
    1. Buccal supports with or without suckers.
  4. Head
    1. Head with tentacle pocket.
    2. Eyes with corneal membranes covering lenses.
    3. Eyes without secondary (= ventral) eyelid.
    4. Figure. Left - Dorsal view of the head of Sepioteuthis sp. (Loliginidae) showing cornea covering lens. Photograph by Mark Norman. Right - Ventrolateral view of the head of Lollicuncula diomedeae showing the absence of a ventral eyelid. Photograph by R. Young.

  5. Funnel
    1. Funnel without lateral adductor muscles.
  6. Mantle
    1. Mantle locking-apparatus extends to mantle edge (except Australiteuthidae)
  7. Fins
    1. Fins with or without posterior lobes.
  8. Shell
    1. Shell a gladius.
  9. Viscera
    1. Gills with branchial canal (except Pickfordiateuthis, unknown in Australiteuthis).
    2. Right oviduct absent.
    3. Females with accessory nidamental glands.
    4. Figure. Diagramatic cross-section through gills. Drawing modified from Naef (1921-23).

  10. Eggs
    1. Eggs, where known, attached to substrate.
    2. Embryo with large external yolk sac.

Discussion of Phylogenetic Relationships

The two families of the Myopsida appear to be closely related. The Australiteuthidae differs from the Loliginidae primarily in the structure of the funnel/mantle locking-apparatus and the position of the mantle component which does not reach the mantle margin. A number of features of phylogenetic importance in the Australiteuthidae, however, are not known: the presence or absence of a branchial canal, an anterior eye pocket, circularis muscles in the suckers, an interstellate connective; the location of spermathecae; the symmetry of the gills; the type and place (pelagic or benthic) of deposition of egg masses and the position of the intestine relative to the cephalic vein and the vena cavae.

References

Brakoniecki, T. F. 1996. A revision of the genus Pickfordiateuthis Voss, 1953 (Cephalopoda; Myopsida). Bull. Mar. Sci., 58: 9-28.

Lu, C. C. 2005. A new family of myopsid squid from Australasian waters (Cepahlopoda: Teuthida). P. 71-82. In: Chotiyaputta, C., E. M. C. Hatfield and C. C. Lu (editors). Cephalopod biology, recruitment and culture. International Cephalopod Symposium and Workshop, 17-21 Feb. 2003. Research Bulletin, Phyuket Marine Biological Center, No. 66, Published by the Center Phuket, Thailand, July 2005, 365 pp.

Naef, A. 1921-1923. Die Cephalopoden. Fauna e Flora del Golfo di Napoli, Monographie 35, Vol I, Parts I and II, Systematik, pp 1-863.

Title Illustrations
Scientific Name Loligo plei
Specimen Condition Live Specimen
View Dorsal
Size 105 mm ML
Copyright ©
About This Page



National Marine Fisheries Service
Systematics Laboratory
National Museum of Natural History
Washington, D. C. 20560
USA

Richard E. Young

Dept of Oceanography
University of Hawaii
Honolulu, Hawaii 96822
USA

Citing this page:

Vecchione, Michael and Young, Richard E. 2005. Myopsida Naef, 1916. Version 20 September 2005 (complete). http://tolweb.org/Myopsida/52670/2005.09.20 in The Tree of Life Web Project, http://tolweb.org/

close box

This page is a Tree of Life Branch Page.

Each ToL branch page provides a synopsis of the characteristics of a group of organisms representing a branch of the Tree of Life. The major distinction between a branch and a leaf of the Tree of Life is that each branch can be further subdivided into descendent branches, that is, subgroups representing distinct genetic lineages.

For a more detailed explanation of the different ToL page types, have a look at the Structure of the Tree of Life page.

close box

Myopsida

Page Content

Articles

Treehouses

Explore Other Groups

random page

top