Chromatophore Arrangement and Distribution in the Gulf Squid Lolliguncula Brevis

Abstract

Fifteen Lolliguncula brevis were divided into three groups based on body size (mantle length). The dorsal mantle, ventral mantle and fins of those squids were observed and the arrangements of chromatophores in those areas were reproduced onto clear acetate. The anatomically fixed arrangements of chromatophores into morphological units and the distribution of those units on the body of the animal were described. There was a significant difference (P≤.01) between the number of chromatophores on the dorsal mantle vs the ventral mantle vs the fins within each of the three groups of animals. There was no significant difference (P≤.01) between the number of chromatophores per mm² for a given body region across the size range encompassed by the three groups (40 mm to 70 mm in mantle length).