Neoteuthidae

Figure. Neoteuthis thielei, ~ 10 cm ML, in situ photograph at a depth of 1130 m by an ROV from the NOAA ship R/V OKEANOS EXPLORER. Arrow points to anterior tip of fin.

The genera are compared in the following table:

1. Arms
   1. Arms with biserial suckers.
   2. Buccal connectives attach to the dorsal margins of arms IV.
      
      
2. Tentacles
   1. Manus of tentacular club divided into two regions, a distal manus with large suckers in mostly four series and a proximal manus with small suckers in more than 10 series. (The number of series may be slightly more at the interface between the proximal and distal manus and, in Narrowteuthis, somewhat less on the distal portion of the dactylus.)
   2. Club locking apparatus extends, at least, along the length of the proximal manus.
   3. Club morphology varies greatly between genera.
   
   
   

   Figure. Top - Oral views of tentacular clubs of Neoteuthis thielei, 83 mm ML, off California. drawing from Young, 1978. Bottom - Alluroteuthis antarctica, Antarctic waters. Drawing from Roper, et al., 1969.

3. Funnel
   1. Funnel with straight locking-apparatus.
      
      
4. Fins
   1. Anterior fin lobes absent; posterior fin lobes free.
   2. Fins mostly attach to dorsolateral sides of mantle.
      

      Figure. Left - Dorsal view of mantle of Neoteuthis sp., 83 mm ML, off California (from Young, 1972). Right - Ventral view of mantle of Alluroteuthis antarctica (from Roper et al., 1969).

5. Photophores
   1. Photophores absent.
      
      
6. Skin
   1. Outer surfaces of arms, head and mantle with thick white tissue (presumably silver in life) in most genera.

No paralarva of any neoteuthid has been positively identified. However, a paralarva off Hawaii was tentatively identified to this genus by a process of elimination rather than the more reliable process of following a size series to identifiable juveniles. One of the keys to identification is the position of the digestive gland in an anterior postion adjacent to the cephalic cartilage. This feature is usually characteristic of families with buccal connectives that attach to the dorsal borders of arms IV. This paralarva had thick, iridescent tissue overlying the posterior part of the head but much of the skin was missing from other regions so the extent of iridescent tissue in an undamaged paralarva is unknown. Head and arm chromatophore patterns are incomplete due to damage. The dotted line indicates the size and position of the digestive gland.

Figure. Ventral and dorsal views of a paralarva tentatively identified as Neoteuthis sp., 5.8 mm ML, Hawaiian waters. The digestive gland (dotted line) is elongate with a blunt anterior end where it abuts the cephalic cartilage.