Onychoteuthis meridiopacifica: Description Continued

1. Arms
1. Length subequal but with arms I slightly smaller; 27-44% of ML.
2. About 50-60 suckers on each arm. 
3. Inner sucker rings smooth.


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Figure. Side view of arm suckers of O. meridiopacifica. Drawings from Rancurel, 1970.

2. Head
1. 8-12 occipital folds are present on each side. The illustration shows 10 folds including the upper one that is barely visible in this drawing. Note the olfactory organ on fold no. 2 from the ventral end.


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Figure. Side-view of head of O. meridiopacifica showing occipital folds. Drawing from Rancurel, 1970.

2. Radula
1. Marginal tooth very long relative to rhachidian tooth and very curved. 
2. Rachidian tooth with small lateral cusps.


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Figure. Radular teeth of O. meridiopacifica in a transverse row. Drawing modified from Rancurel, 1970.

3. Fins
1. Fin length 40-50% of ML.
2. Fin width 70-90% of ML.
3. Apical fin angle 120-140°.
4. Gladius
1. The gladius with solid dorsal keel.
2. Conus with flared ventral margin.
3. Rostrum a small flap arising from the posterior end of the keel.


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Figure. Various aspects of the gladius of O. meridiopacifica. Top - Side and ventral views of gladius. Bottom left- Ventral view of the conus and rostrum. Bottom middle - Cross-section of gladius. Bottom right - Side view of gladius conus and rostrum. All drawings from Rancurel (1970).

5. Measurements

   Specimen	1	2	3	4	5	6	7	8	9	10
   Sex	Male	Male	Fem.	Male	Fem.	Fem.	Fem.	Fem.	Fem.	Male	Mean
   Mantle length, mm	61	52	43	62	56	51	45	42	55	63
   Mantle width, %ML	30	32	35	31	34	38	32	33	28	28	31.9
   Fin length, %ML	43	46	48	45	42	45	42	45	41	46	44.3
   Fin width, %ML	86	90	90	75	86	81	80	87	73	84	83.2
   Head width, %ML	22	26	24	21	21	26	21	23	25	22	23.0
   Arm I, length, mm	33	27	31	36	28	31	30	31	27	34	30.7
   Arm II, length, mm	35	38	35	37	34	37	33	37	32	39	35.7
   Arm III, length, mm	34	37	37	40	34	38	36	36	33	40	36.4
   Arm IV, length, mm	35	39	32	39	38	34	33	33	37	44	36.1
   Tentacle length, %ML	54	73	58	53	60	53	55	53	50	58	56.7
   Tentacle club, %ML	24	23	25	21	22	22	22	22	20	20	22.0
   Hook count	16	17	17	19	18	18	17	18	18	18

   These measurements and counts are from Rancurel and Okutani, 1990. Most of the figures have been rounded to the nearest whole number.

Comments

This description is from Rancurel (1970) and Rancurel and Okutani (1990).

References

Rancurel, P. 1970. Les contenus stomacuax d'Alepisaurus ferox dans le Sud-ouest Pacifique (céphalopodes). Cah. O.R.S.T.O.M., ser. Océanogr., 8: 3-87.

Rancurel, P. and T. Okutani. 1990. A new species of squid genus Onychoteuthis from the Southwest Pacific. Venus, 49: 25-30.