FISHERY BULLETIN: VOL. 76. NO. 2 



Amphipods: also uncommon except in juveniles 

 which took the following 15 species: Caprella cicur 

 and two other species of^ Caprella, Cerapus sp., 

 Corophium sp., Gammaropsis sp., Lysianassa 

 ceratina, L. uariegata, Jassa sp., Maera sp., 

 Paramoera capensis, Parelasmopus suluensis, 

 Photis sp., and two unidentified species. 



Harpacticoid copepods: eight species. 



Insects: larvae of the chironomid Telmatogeton 

 minor. 



Tanaidaceans: Leptochelia barnardi, uncom- 

 mon. 



Molluscs: rhaciglossid. 



DENTITION AND GUT MORPHOLOGY 



Diplodus ceruinus — there are six upper and four 

 lower incisors which are narrower than those of Z). 



sargus, and there are fewer molars, the number 

 increasing with age (Figure lOA). This would in- 

 dicate that adult D. cervinus feed on softer foods 

 than D. sargus , which is borne out as the diet of the 

 former consists primarily of polychaetes, whereas 

 the latter took amphipods and molluscs as well. 

 The gut of D. ceruinus is short with a G/S ratio of 

 0.7 in a 16.5-mm fish and 0.95 in one 74 mm long. 



Diplodus sargus — there are four stout incisors 

 and three to four rows of fairly large molars in 

 each jaw (Figure lOB), the latter increasing in size 

 and number with age. The teeth are those of a 

 typical omnivore (Weatherly 1972). The G/S ratio 

 was 0.76 in a 16.5-mm fish and this is within the 

 range of omnivores as defined by Nikolsky ( 1963). 



Sarpa salpa — this species shows a change in 

 dentition correlated with age and diet. The young 

 fish are carnivorous and have short, pointed coni- 



FlGURE 10.— Dentition. A. Medial view of 

 the left upper and lower jaws oi Diplodus 

 cervinus (MSC 75-36, 94 mm SL). B. Me- 

 dial view of the left upper and lower jaws 

 ofZ). sargus (MSC 75-34, 107 mm SL). C. 

 Lateral view of the upper and lower jaws 

 of a juvenile Sarpa salpa (MSC 75-39, 20 

 mm SL). D. Lateral view of a single tooth 

 of a subadult S. salpa (MSC 75-37, 39 mm 

 SL). E. Lateral view of the upper and 

 lower jaws of an adult S. salpa (RUSI 74- 

 323, 99 mm SL). 



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