Complete

Enoploteuthidae Pfeffer 1900

Kotaro Tsuchiya and Richard E. Young
Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window
The family contains the following four genera and about 40 species.
Containing group: Enoploteuthid families

Introduction

Enoploteuthid squid are small, between 3 and 13 cm in mantle length. All open-ocean species occupy upper mesopelagic waters during the day. In the regions where the mesopelagic zone intersects the slopes of land masses (i.e., the mesopelagic boundary zone) some species may occur at shallower depths. Many species are known to undergo extensive daily vertical migrations which may be characteristic of all species in the family. The species are noted for their colorful array of numerous photophores distributed primarily over the ventral surfaces of the head, arms, funnel and mantle.

Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window

Figure. Ventral view of a bioluminescing Watasenia scintillans, Sea of Japan. Photograph by Danté Fenolio

Brief diagnosis:

A member of the enoploteuthid families ...

Characteristics

From Young, et al., 1998.
  1. Tentacles
    1. Armature on club manus in two or three series including one or two series of hooks.

  2. Arms
    1. Hooks, in two series, present on all arms; suckers present on all arm tips except arms IV in Abraliopsis and Watasenia.

  3. Photophores
    1. Numerous, small integumental photophores on mantle, funnel, head and arms.
    2. Photophores absent from tentacles, viscera and, usually, fins.
    3. Eyeball with photophores in single line; anterior and posterior-most photophores generally largest.

  4. Tail
    1. Tail broad and extends well beyond conus of gladius.
    2. Tail tissue with numerous vesicles.

  5. Viscera
    1. Nidamental glands absent.

Comments

The following table compares characteristics of subadults for the genera of Enoploteuthidae.

  Enoploteuthis
Abralia
Abraliopsis
Watasenia
Thick tail extends beyond posterior end of fins
Yes
No
No
No
Number of hook series on tentacular clubs
2
1
2
1
Tips of arms IV with large, spherical photophores covered with black chromatophores
No
No
Yes
Yes
Hectocotylus
 Right arm IV
 Left or Right arm IV
  Right arm IV  Right arm IV
Arms with distal suckers
Arms I-IV
 Arms I-IV  Arms I-III  Arms I-III
Pigmentation of oral surface of buccal membrane
Primarily in chromatophores
In chromatophores
In epithelium
In epithelium
Habitat
Tropical/temperate waters world wide
Tropical/temperate waters world wideTropical/temperate waters world wideTemperate waters of Northwest Pacific

Nomenclature

A list of all nominal genera and species in the Enoploteuthidae can be found here. The list includes the current status and type species of all genera, and the current status, type repository and type locality of all species and all pertinent references.

Discussion of Phylogenetic Relationships

Young and Bennett (1988) found strong similarities in photophore structure between Watasenia and Abraliopsis and between Abralia and Enoploteuthis. They did not, however, distinguish between plesiomorphic and apomorphic characters. Relationships, therefore, remain uncertain although the similarity between Watasenia and Abraliopsis is supported by the shared presence of several other characters (see respective pages).

Life history

Members of the family lack nidamental glands but have enlarged oviducal glands. Spawning females produce long gelatinous strings with eggs embedded in a single series. The eggs are about 1 mm long and oval to spherical in shape, depending on the species. Developing embryos are often found in plankton tows taken in tropical near-surface waters. The enoploteuthid eggs in the photo on the left, taken from a plankton tow, consist of two Abralia trigonura on the left (one with its jelly layer still somewhat intact), probably Abraliopsis sp. in the center and Enoploteuthis reticulata on the right. The latter is distinctive in having a pitted chorion which scatters the light giving a less transparent appearance.

Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window

Figure. The advanced embryo on the left (photograph enlarged relative to that of the eggs on the right) shows the large internal yolk sac and a central black dot which is the developing ink sac. Enoploteuthid paralarvae are often the most abundant young cephalopods found in the near-surface plankton of tropical and subtropical seas (Young and Harman, 1985). Enoploteuthid eggs, off Hawaii. Abraliopsis sp. embryo, off Hawaii. Copyright © 1996, R. E. Young.

References

Young, R. E. and T. M. Bennett. 1988. Photophore structure and evolution within the Enoploteuthidae (Cephalopoda). P. 241-251. In: M. R. Clarke and E. R. Trueman (Eds.). The Mollusca. Vol. 12 Paleontology and Neotology of Cephalopods. Academic Press, N.Y., 355pp.

Young, R. E. and R. Harman. 1985. Early life history stages of enoploteuthin squid (Cephalopoda: Teuthoidea: Enoploteuthidae) from Hawaiian waters. Vie Milieu 35: 181-201.

Young, R. E., L. A. Burgess, C. F. E. Roper, M. J. Sweeney and S. J. Stephen. 1998. Classification of the Enoploteuthidae, Pyroteuthidae and Ancistrocheiridae. Smithson. Contr. Zool., 586: 239-256.

Title Illustrations
Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window
Scientific Name Abralia trigonura
Location Off Kona coast of Hawaii Island
Specimen Condition Live Specimen
Identified By R. E. Young
Behavior Squid swimming close to ocean floor at night at a depth of about 25 m, attracted by photographer's lights.
Sex Female
Size 30- 40 mm ML (guess)
Copyright © 2017 Jeffrey Milisen
About This Page


Tokyo University of Fisheries, Tokyo, Japan


University of Hawaii, Honolulu, HI, USA

Correspondence regarding this page should be directed to Kotaro Tsuchiya at

All Rights Reserved.

Citing this page:

Tsuchiya, Kotaro and Richard E. Young. 2018. Enoploteuthidae Pfeffer 1900. Version 29 March 2018. http://tolweb.org/Enoploteuthidae/19634/2018.03.29 in The Tree of Life Web Project, http://tolweb.org/

edit this page
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

Enoploteuthidae

Page Content

articles & notes

collections

people

Explore Other Groups

random page

  go to the Tree of Life home page
top