Mastigoteuthis agassizii Verrill, 1881

Introduction

M. agassizii is the type species of the genus.

Diagnosis

A mastigoteuthid ...

• with integumental photophores.
• with smooth-ringed arm suckers.

Characteristics

1. Arms
   1. Arm suckers with oblique aperatures on inner rings and smooth inner margins. image info

      Figure. Oral view of sucker of M. agassizii from middle of a lateral arm. Drawing from Verrill (1881b).

2. Tentacles
   1. Tentacles shaped like "whip-lash." Club covers half of tentacle length. Club base with scattered suckers mostly in two series for some distance. (Verrill, 1881b).
   2. Club suckers with circular aperature often with 2-3 teeth on one side (Verrill, 1881b).
      image infoimage info

      Figure. Tentacular club of M. agassizii. Left - Aboral view of a portion of the club. Right - Various views of club suckers. Drawings from Verrill (1881b).

3. Funnel locking-apparatus
   1. Funnel locking apparatus: "...earshaped, elevated cartilage, on each side, fitting into corresponding deep, circumscribed pits..." (Verrill, 1881b).
   image infoimage info

   Figure. Funnel-mantle locking-apparatus of M. agassizii. Left - Frontal view of the funnel component, fresh squid, off N.E. coast of USA. Photograph by M. Vecchione. Right - Lateral view of the head and funnel showing the funnel locking-apparatus and a portion of the mantle reflected back to reveal a frontal view of the mantle component. Drawing from Verrill (1881b).

4. Mantle
   1. Tubercules absent from mantle and other integument.
5. Photophores
1. Integumental photophores on dorsal and ventral mantle, dorsal fin, head and arms (Verrill, 1881b).
2. Eyelid photophores present (Young, 1972). image info

   Figure. External view of a portion of the mantle skin of M. agassizii showing bare photophores (black arrows) and photophores with their covering chromatophores (white arrows), fresh squid, off N.E. coast of USA. Photograph by M. Vecchione.

6. Fins
   1. Fin length about half combined head and body.
7. Measurements

   Source	Verrill, 1881b	Verrill, 1881b
   Sex	Male	Male
   Mantle length	46	99
   Mantle width	15	23
   Fin length	30	60
   Fin width	42	75
   Eye diameter	7.5	9
   Arm I, length	24	45
   Arm II, length	33	60
   Arm III, length	34	60
   Arm IV, length	80	112
   Tentacle length	--	312

Comments

This is the only species of Mastigoteuthis that has integumental photophores but smooth arm sucker rings.

Distribution

Type locality: Off northeast coast of the United States at 33°25'N, 76°W and 34°28'N, 75°23'W.

References

Verrill, A.E. 1881a. Report on the Cephalopods, and on Some Additional Species Dredged by the U.S. Fish Commission Steamer "Fish Hawk", During the Season of 1880. Bulletin of the Museum of Comparative Zoology, 8(5):99-116.

Verrill, A.E. 1881b. The Cephalopods of the North-eastern Coast of America. Part II. The Smaller Cephalopods, Including the "Squids" and the Octopi, with Other Allied Forms. Transactions of the Connecticut Academy of Sciences, 5: 259-446.