Paralarvae are known as small as 1.9 mm ML. The smallest paralarvae are extremely slender with a mantle width about 25% of the ML. Between this size and about 4-5 mm ML (Fig. A) they are easily recognized by their slender appearance and a distinctive elongate patch of large chromatophores along the dorsal midline. The eyes are dorsoventrally elongate and strongly buldge from the head. Club suckers are in two series, large (about the same size as the arm suckers) and prominent. At roughly 4-5 mm ML (Fig. B) the paralarvae begin a strong morphological change. They start to become relative broad, the eyes become hemispherical and the fins become much more prominent. At 7 mm (Fig. C) the squid is very broad for its length. Chromatophores are small and scattered but larger on the dorsal surfaces than ventral surfaces. On the ventral surface of the head the chromatophores are deep within the tissue and not readily visible in preserved specimens. By 12 mm ML the V-shaped funnel groove and the distinctive rostrum are present and hooks are beginning to form in the medial-ventral series on the club.
Figure. Ventral and dorsal views of growth stages of paralarvae of W. rancureli, Hawaii. A - Small, slender-stage paralarva, 2.4 mm ML. B - Paralarva in transition between slender and squat-body forms, 4.5 mm ML. C - Squat-stage paralarva, 7.0 mm ML. The scale bar is 1 mm. Drawings by R. Young.
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