Burrow morphology of two callianassid shrimps, Callianassa japonica Ortmann, 1891 and Callianassa sp. (=C. japonica: de Man, 1928) (Decapoda: Thalassinidea)

Polyester resin casts of burrows of the thalassinidean shrimps, Callianassajaponica Ortmann, 1891 and Callianassa sp. (= C. japonica: de Man, 1928), were collected on intertidal sandflats hi western Kyushu, Japan. The difference in basic architecture of the burrows of these two species was obvious: the burrow of C. japonica had alternating shafts and chambers, with a single surface opening, while that of Callianassa sp. was basically Y-shaped, with two surface openings. The average dimensions of individual components of the burrows are given for each species and possible functions of these components, especially with regard to the shrimps' trophic modes, are discussed.