Bioluminescent emissions of the deep-water pandalid shrimp, Heterocarpus sibogae De Man, 1917 (Decapoda, Caridea, Pandalidae) under laboratory conditions

Abstract

Bioluminescent behaviour of deep-sea decapods is difficult to study under long-term laboratorymaintenance, because most deep-sea organisms suffer from high mortality in such conditions. Theobjective of the present study was to determine the survival of the deep-water pandalid shrimp,Heterocarpus sibogaeDe Man, 1917 and its ability to produce bioluminescence when maintainedin the laboratory.H. sibogaeexhibited bioluminescence by emitting two streams of blue luminoussecretions from the mouth when disturbed. The luminous material decayed rapidly and disappearedin seconds. Shrimps retreated from the luminous region immediately after secretion, suggestingthat bioluminescence is a defence response. Under laboratory conditions,H. sibogaecan produceluminous secretions for at least 43 days of maintenance. Maximum emission time was recorded in anon-ovigerous female that reached 634 seconds. Males and non-ovigerous females showed a similaraverage emission time of about 30 seconds. Ovigerous females, however, produced significantlylonger emissions with an average of 103 seconds, suggesting that these may contain larger amountsof the key chemical for bioluminescence, coelenterazine, than males and non-ovigerous fe