Egea inermis Joubin, 1933

Egea contains one recognized species. Voss, et al. (1992), however, suggest that two species exist.

Introduction

These are moderately sized squid reaching 420 mm ML Nesis, (1982) and are poorly known.

Diagnosis

A taoniin ...

• with anterior third of fins attaching to mantle.
• with S-shaped lateral ocular photophore.
• with funnel valve.

Characteristics

1. Arms
1. Arms I and II of large males with modified tips with abruptly much smaller suckers arranged in four series.
2. Arms III of large females with terminal photophores.
   
   

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   Figure. E. inermis, oral views of the modified arm tips of a large male and a large female. Drawings from N. Voss, 1974 (p. 944, Figs. 2a, 2d, 2e).
   

2. Tentacles
1. Tentacular club with suckers only.
2. Tentacular club without carpal cluster.
3. Two series of suckers and pads on distal 3/4 of tentacular stalk.
   
   

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   Figure. E. inermis, male, 198 mm ML. Oral view of the tentacle. Drawing from Voss, 1974 (p. 943, Fig. 1b).

   
   
3. Head
   
   1. Beaks: Descriptions can be found here: Lower beak; upper beak.
      
      
4. Funnel
   1. Valve present.*
   2. Funnel organ with inverted V-shaped ventral pads and triangular flaps on dorsal organ.
      

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      Figure. Ventral view of funnel organ and funnel valve of E. inermis, subadult male, 207 mm ML. Drawing from Voss (1980, p. 397).

5. Mantle
   1. Tubercles absent from point of funnel-mantle fusion.
      
      
6. Fins
1. Anterior third or more of fin attaches to mantle.**
   
   
7. Photophores
1. Two ocular photophores: medial organ with narrow, crescent-shaped photogenetic region; lateral organ with narrow S-shaped photogenetic region and encircling 2/3 of lens.
2. Photophores on tips of arms III in subadults; adults unknown.
   

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   Figure. Lateral and lateroventral views of ocular photophores of E. inermis, subadult male, 207 mm ML. Drawings from Voss (1980, p. 397).

*Unusual within subfamily; shared with Megalocranchia.
**Unusual within subfamily; shared with Teuthowenia.

Comments

Characteristics are from Voss (1980).

Life History

Two young stages have been illustrated.

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Figure. Top - Dorsal view of paralarva of E. inermis, ca. 7 mm ML. Bottom - Ventral view of a juvenile of E. inermis, ca 48 mm ML. Drawings from Voss (1980, p. 397).

Distribution

Egea inermis is distributed circumglobally in tropical waters, and extends into the Gulf of Mexico, the western North Atlantic in the Gulf Stream system and in the northwestern Pacific in the Kuroshio System (Voss, 1980).

Other Names for Egea inermis Joubin, 1933

• Egea Joubin, 1933

References

Nesis, K. N. 1982/87. Abridged key to the cephalopod mollusks of the world's ocean. 385,ii pp. Light and Food Industry Publishing House, Moscow. (In Russian.). Translated into English by B. S. Levitov, ed. by L. A. Burgess (1987), Cephalopods of the world. T. F. H. Publications, Neptune City, NJ, 351pp.

Voss, N. A. 1974. A Redescription of Egea Inermis Joubin, 1933 Voss, N. A. 1980. A generic revision of the Cranchiidae (Cephalopoda; Oegopsida). Bull. Mar. Sci. 30: 365-412.

Voss, N. A. 1980. A generic revision of the Cranchiidae (Cephalopoda; Oegopsida). Bull. Mar. Sci., 30: 365-412.

Voss N. A., S. J. Stephen and Zh. Dong 1992. Family Cranchiidae Prosch, 1849. Smithson. Contr. Zool., 513: 187-210.