Martialia hyadesi: Description continued

1. Arms
   1. Arms < half ML; arms II=III>I=II.
   2. Arm suckers biserially arranged and relatively small (largest suckers midarm); except for hectocotylus, each arm usually with 75-78 suckers (range 66-87).
      
   3. Arm suckers with 5,7 or 9 teeth on distal 2/3 of sucker rings, depending on sucker size; central tooth generally slightly larger than lateral teeth.
      
      

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      Figure. Oral views of the largest arm suckers of M. hyadesi showing sucker dentition. Drawings from Rodhouse and Yeatman (1990).

2. Tentacles
   1. Proximal region of club with suckers in two series with each sucker attached to base of trabecula as on arms, no locking apparatus is present; middle (manus) region suckers in tetraserial arrangement with small lateral suckers attached to trabeculae and large medial suckers attached directly to club; carpal area suckers similar in dentition to arms suckers.
      
   2. Manus area of club with suckers in four series; large, medial club suckers with 15 relatively large, sharp teeth alternating with 15 smaller blunt teeth around entire ring; distal teeth, especially blunt ones, distinctly larger; distal medial tooth larger than others but degree of enlargement variable.
      
      

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      Figure. Oral views of club suckers of M. hyadesi showing dentition. Drawings from Rodhouse and Yeatman (1990).

   3. Dactylus area of club with suckers in four series; trabeculae reduced, low protective membrane better developed on ventral margin; sucker dentition similar to that of manus-area suckers.
   4. Club generally with about 155 suckers total.
   photo
3. Head
   1. Beaks
      1. Lower beak with shoulder tooth, transparent strip along jaw-edge extension, low wing fold, broad hood with notch, rostral edge about equal to hood length; lateral wall without fold, rostrum with pronounced hook. Color blacker than general in ommastrephids.
         
      2. Calculated regression (r² = 0.756; n = 67) of lower rostral length (r) in mm against wet weight in grams  (w):

         ln w = 2.405 = 2.012 ln r

      3. Calculated regression (r² = 0.736; n = 67) of lower rostral length (r) in mm against mantle length in mm (l):

         l = 102.0 + 29.47 r
         

         

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

         
         

         Figure. Four views of the lower beak of M. hyadesi and a side view (lower right) of the upper beak. Drawings from Rodhouse and Yeatman (1990).

   2. Foveola, in funnel groove, with 7 longitudinal folds; side pockets absent.
      

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      Figure. Ventral view of the funnel groove of M. hyadesi showing the foveola. Drawing from Rodhouse and Yeatman (1990).

   3. Statoliths
      
      

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      Figure. Anterior (left) and posterior (right) views of a statolith of M. hyadesi. Statolith length - 1.1 mm. Drawings from Rodhouse and Yeatman (1990).

4. Funnel
   1. Funnel organ
      
      

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      Figure. Ventral view of the funnel cut open of M. hyadesi showing the shape of the funnel organ. Drawing from Rodhouse and Yeatman (1990).

       

   2. Funnel/mantle locking apparatus typical for family but with mantle component showing similarity to that of Todarodes pacificus in cartilage at the anterior tip (see Comparisons of  the funnel-locking appartus).
      
      

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      Figure. Frontal views of the funnel/mantle -locking apparatus of M. hyadesi. Photographs by R. Young. Drawing from Rodhouse and Yeatman (1990).

5. Fins
   1. Fin length about 40% of ML.
   2. Posterior fin angle 47-55°.
      
      
6. Photophores
   1. Photophores absent.
      
      
7. Pigmentation
   1. In live specimens: Dorsal surface of mantle with very dark purple coloration; lateral mantle red/brown; ventral mantle silver/white.
      
      
8. Gladius
   1. Gladius with typical ommastrephid shape, reinforced with one central and two lateral ribs; vane 20% of total length.
      
   

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   Figure. Ventral view of the gladius of M. hyadesi with cross-sections. Drawing from Rodhouse and Yeatman (1990).

9. Viscera
   1. Spermatophore
      
      

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      Figure. Spermatophore of M. hyadesi. Drawing from Rodhouse and Yeatman (1990).

10. Measurements and counts
    

    Character	Range	mean	+/-sd		Range	mean	+/-sd	Type specimen
    Males				Females
    Mantle width index	19.0-29.7	23.4	2.1		19.9-26.8	22.8	1.6	19.0
    Head length index	12.9-17.4	15.8	1.0		12.6-17.6	15.7	1.0	19.0
    Head width index	12.0-18.4	15.5	1.4		13.2-17.7	15.5	1.2
    Fin length index	38.2-45.6	41.6	1.9		38.4-45.5	42.0	1.8	43.0
    Fin width index	54.3-66.5	60.0	2.8		55.5-64.3	59.4	2.3	55.5
    Arm I length index	29.5-43.8	37.8	3.3		29.9-43.2	36.9	2.8	37.0
    Arm II length index	34.6-48.8	41.5	3.0		35.2-45.7	40.4	2.7	41.0
    Arm III length index	35.5-49.2	42.0	3.2		35.7-46.1	40.9	2.6	43.0
    Arm IV length index	27.7-36.5	32.5	2.3		30.1-40.8	35.2	2.6	37.0
    Hecto length index	6.6-14.9	10.5	2.3
    Tentacle length index	49.3-66.9	58.6	4.7		44.9-70.2	59.8	5.2
    Club length index	38.2-55.6	48.4	4.1		37.3-57.0	48.6	4.2	50.0
    Gladius length index	91.9-100.0	95.1	1.6		91.9-89.9	95.5	1.6
    Gladius width index	2.8-4.7	3.3	0.4		2.6-3.7	3.1	0.2
    Rhachis length index	74.5-85.5	78.5	2.6		72.6-81.7	77.4	2.0
    Rhachis width index	3.8-4.7	4.3	0.2		3.9-5.0	4.3	0.3

Comments

The above characteristics are from Rodhouse and Yeatman (1990). 

References

Rodhouse, P. G. and J. Yeatman. 1990. Redescription of Martialia hyadesi Rochebrune and Mabille, 1889 (Mollusca: Cephalopoda) from the Southern ocean.Bull. Br. Mus. nat. Hist (Zool.), 56(2): 135-143.