Overview

Brief Summary

Introduction

Iridoteuthis iris is a small heteroteuthin (28 mm ML) with very large eyes, short mantle that projects ventrally anterior to the eye lenses and unusually large fins. It is known only from Hawaiian waters.



Figure. Iridoteuthis iris. Top - Dorsal and ventral views, male. Drawings from Harman and Seki (1990). Bottom - Ventrolateral view of live animal. © 1996 Thomas Burch.

Brief diagnosis

An Iridoteuthis ...

  • without elaborate ventral protective membrane on right arm I in mature males.
  • with size differentials in some arm suckers between dorsal and ventral series in males.
  • with bare, elongate sucker stalks on tips of arms III and IV in females.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Comprehensive Description

Characteristics

  1. Arms (Harman and Seki, 1990)
    1. Males
      1. Arms I in males with dorsal series of suckers reduced in size on distal region of arms.
      2. Arms II in males each with slightly enlarged suckers on middle of arms.
      3. Arms III in males each with several greatly enlarged suckers in midarm of dorsal series; distal to enlarged suckers a short area without suckers and only sucker stalks (=pedicels).
      4. Arms IV ends in males each with suckers in four series.
      5. Enlarged dorsal keels (flags) at tips of arms I-III in males.
      6. Figure. Oral view of the brachial crown of I. iris, male, 24 mm ML. Drawing from Harman and Seki (1990).


        Figure. Oral view of the arm crown of I. iris, male. This appears to be the same specimen from which the above drawing was made. Photograph by R. Young.

        Figure. Arm tips of I. iris, male, same specimen as above. Left - Oral view of arms I and II. Middle - Oral view of arm III. Right - Medial view of arm IV. Photographs by R. Young.

    2. Females
      1. Tips of arms I in females bare.
      2. Distal region of each arm III with elongate trabeculae, no suckers.
      3. Distal region of each arm IV with elongate trabeculae, no suckers; proximal half with relatively large suckers; next quarter with smaller suckers in somewhat irregular series.
      4. Figure. Oral view of the brachial crown of I. iris, female, 21 mm ML. Drawing from Harman and Seki (1990).

        Figure. Oral views of the arms of I. iris, female. Specimen appears to be the same as that from which the drawing above was made. Left - Left arms I-IV with arm I on the left of the photograph. Middle - Arm III tip. Right - Arm IV tip. Photographs by R. Young.

Comments

More details of the description of I. iris can be found here.

Sexual dimorphism of arms apparent in animals larger than 8 mm ML (Harman and Seki, 1990).

See the Iridoteuthis page for a table comparing the most obvious differences between the species.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Range Description

Iridoteuthis iris occurs in the open ocean near to the Hawaii Islands and Colahan and Kammu seamounts (Reid and Jereb 2005). It has been captured at a variety of localities along the Hawaiian Archipelago from about 21 °N, 157 °W to about 32 °N, 177 °E. All captures are close to islands or seamounts and are from relatively shallow fishing depths (c. 150-300 m).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Type locality: Off the south coast of Molokai Isl, Hawaiian Archipelago, central North Pacific from over a bottom depth of 280 m. Subsequently captured at a variety of localities along the Hawaiian Archipelago from about 21°N, 157°W to about 32°N, 177°E. All captures are close to islands or seamounts and are from relatively shallow fishing depths (ca. 150-300 m). I. iris appears to be a member of the mesopelagic boundary fauna occuring over bottom depths of less than 450 m (Young, 1995).

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
Females attain a larger body size (up to 28mm in mantle length) compared to males (up to 24 mm in mantle length) (Reid and Jereb 2005). This is a pelagic species (Reid and Jereb 2005). Mature males have enlarged suckers on their third pair of arms (Norman 2003). Members of the subfamily Heteroteuthinae are free swimming in the open ocean (Norman 2003). Iridoteuthis iris appears to be a member of the mesopelagic boundary fauna occurring over bottom depths of less than 450 m (Young 1995).

Systems
  • Marine
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Pelagic, found in the open ocean.
  • Jereb, P.; Roper, C.F.E. (Eds)(2005). An annotated an illustrated catalogue of cephalopod species known to date. Volume 1: Chambered nautilusses and sepioids (Nautilidae, Sepiidae, Sepiolidae, Sepiadariidae, Idiosepiidae and Spirulidae). FAO Species Catalogue for Fishery Purposes 4(1). FAO, Rome. 262p., 9 colour plates.
Creative Commons Attribution 3.0 (CC BY 3.0)

© WoRMS for SMEBD

Source: World Register of Marine Species

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

bathyal
  • UNESCO-IOC Register of Marine Organisms
Creative Commons Attribution 3.0 (CC BY 3.0)

© WoRMS for SMEBD

Source: World Register of Marine Species

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Depth range based on 3 specimens in 1 taxon.
Water temperature and chemistry ranges based on 3 samples.

Environmental ranges
  Depth range (m): 202 - 236
  Temperature range (°C): 14.581 - 15.502
  Nitrate (umol/L): 5.474 - 7.983
  Salinity (PPS): 34.555 - 34.631
  Oxygen (ml/l): 4.891 - 4.897
  Phosphate (umol/l): 0.457 - 0.699
  Silicate (umol/l): 6.541 - 9.519

Graphical representation

Depth range (m): 202 - 236

Temperature range (°C): 14.581 - 15.502

Nitrate (umol/L): 5.474 - 7.983

Salinity (PPS): 34.555 - 34.631

Oxygen (ml/l): 4.891 - 4.897

Phosphate (umol/l): 0.457 - 0.699

Silicate (umol/l): 6.541 - 9.519
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
DD
Data Deficient

Red List Criteria

Version
3.1

Year Assessed
2012

Assessor/s
Barratt, I. & Allcock, L.

Reviewer/s
Reid, A., Rogers, Alex & Bohm, M.

Contributor/s
Herdson, R. & Duncan, C.

Justification
Iridoteuthis iris has been assessed as Data Deficient as very little is known of this species. Further research is recommended before an accurate assessment can be made.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Population

Population
The population size of this species is unknown.

Population Trend
Unknown
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Threats

Major Threats
The threats to this species are unknown.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Management

Conservation Actions

Conservation Actions
Basic research is required on this species to elucidate its distribution, population size and life history characteristics.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Iridoteuthis iris

Iridoteuthis iris is a species of bobtail squid native to the northern central Pacific Ocean; it occurs near the Hawaiian Islands off the southeast and northwest Hancock, Colahan, and Kammu seamounts. There exists a doubtful record from the Ceram Sea. Unlike most other bobtail squid, I. iris is pelagic and lives in the open ocean.[1][2]

Females of this species grow to 28 mm in mantle length (ML), while males are not known to exceed 24 mm ML.[1]

The type specimen was collected off the south coast of Molokai in Hawaii. It was originally deposited at the National Museum of Natural History in Washington, D.C., but is no longer extant.[3]

References

  1. ^ a b Reid, A. & P. Jereb 2005. Family Sepiolidae. In: P. Jereb & C.F.E. Roper, eds. Cephalopods of the world. An annotated and illustrated catalogue of species known to date. Volume 1. Chambered nautiluses and sepioids (Nautilidae, Sepiidae, Sepiolidae, Sepiadariidae, Idiosepiidae and Spirulidae). FAO Species Catalogue for Fishery Purposes. No. 4, Vol. 1. Rome, FAO. pp. 153–203.
  2. ^ Harman, R.F. & M.P. Seki 1990. Iridioteuthis iris (Cephalopoda: Sepiolidae): new records from the central north Pacific and first description of adults. Pacific Science 44(2): 171-179.
  3. ^ Current Classification of Recent Cephalopoda
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!