THE BATHYPELAGIC ANGLER FISH 

 CERATIAS HOLBOLLI KROYER 



By Robert Clarke, m.a. 

 (Plate I; Text-figs. 1-6) . 



INTRODUCTION 



Bertelsen (1943) considers that the deep-sea angler fishes or Ceratioidea are, in some respects, the 

 most peculiar and specialized of all fishes. They derive their name from Ceratias holbolli Kroyer, which 

 is the largest species in the group and the fish from which Regan (1925a) first described dwarf-males. 

 Yet of this fish only twelve specimens, several of them damaged, have been recorded since Kroyer 

 erected the genus and species in 1844. Bertelsen gives a list of these, all of them from arctic or boreal- 

 arctic seas. 



Furthermore, Bertelsen has described the remarkable apparatus for extending and retracting the 

 fishing lure in C. holbolli. His new interpretation of the structures involved led him to revise the 

 systematics of the family Ceratiidae which Regan & Trewavas (1932) had divided into the three genera 

 Ceratias Kroyer, 1844, Mancalias Gill, 1878, and Cryptopsaras Gill, 1883. Bertelsen concludes that 

 Mancalias is invalid and actually comprises juveniles of Ceratias. Within the genus Ceratias he reduces 

 the number of species to a northern C. holbolli and a southern C. tentaculatus. 



The following account includes the description of a new specimen of C. holbolli. It is from Antarctic 

 seas, and its oceanic origin makes it specially interesting, since the other adult individuals have been 

 taken from neritic seas. Furthermore, it is the first large adult to be recorded from the southern 



hemisphere. 



MATERIAL 



During the Antarctic whaling season 1947-8 I was able to examine a number of Sperm Whales 

 {Physeter catodon) on board the whaling factory ship ' Southern Harvester'. The stomach contents of 

 these whales consisted principally of squid, but occasionally teleost fish were present. In a later 

 account it is hoped to deal generally with the occurrence of fish in the stomachs of Sperm Whales. 



The present paper refers repeatedly to a single adult female of Ceratias holbolli which was found in 

 the stomach of Whale no. SH 156, Sperm tf, 50-0 ft. (15-2 m.) long, on 21 December 1947. The whale 

 was worked up very shortly after capture, the noon position of the factory ship being then 61 ° 20' S, 

 102 50' E. The first stomach was full, containing many individuals of the squid Moroteuthis ingens 

 Smith. On raking these over I found a large Ceratiid fish scarcely touched by digestive action and with 

 the fishing lure intact. There were no other fish present. 



The specimen was removed from the flensing deck and was measured and sketched whilst still fresh. 

 The body cavity was injected with 10 % neutral sea-water formalin, and the fishing lure removed for 

 safe transport before both fish and lure were fixed in formalin. 



The fish has since been presented to the British Museum (Natural History) where I have been able 

 to examine it further and to compare it with other Ceratiids in the national collection. 



ACKNOWLEDGEMENTS 

 I am indebted to Messrs Christian Salvesen and Co., owners of the ' Southern Harvester', and to the 

 master, Captain Konrad Granoe, for facilities afforded on board that vessel. I also wish to thank the 

 Director and Trustees of the British Museum (Natural History) for working accommodation and for 



