HOBSON: FEEDING RELATIONSHIPS OF FISHES 



Figure 37. — Exallias brevis, a blenny, showing typical diurnal attitude. 



In contrast to these food data, Hiatt and Stras- 

 burg (1960) found only filamentous algae and de- 

 tritus in the single E. brevis (80 mm) that they 

 examined in the Marshall Islands. 



CONCLUSION. — Exallias brevis is a diurnal 

 species that feeds largely on scleractinian corals, 

 both tissue and mucus. 



Cirripectits variolosus (Valenciennes) 



During the day, this relatively small blenny 

 moves about close to cover on the reef, remaining 

 in contact with the substratum. Though numer- 

 ous, it is not seen after dark, when presumably it is 

 secreted in reef crevices. 



The guts of both specimens (66 and 80 mm) 

 collected during midday contained filam.entous 

 algae (about 40% of the diet volume) and what 

 appeared to be detritus (50 to 60%). In addition, 

 one contained a few scleractinian coral fragments 

 (5%). Except for the coral fragments, the diet of 

 these two individuals was the same as that of one 

 specimen of this species examined by Hiatt and 

 Strasburg (1960) in the Marshall Islands. 



CONCLUSION. — Cirripectus variolosus is a 

 diurnal species that feeds mostly on algae and 

 detritus. 



Plogiotremus goslinei (Strasburg) — 

 sabre-toothed blenny 



During the day, P. goslinei hovers a meter or so 

 above the reef, from which position it attacks 

 larger fishes that incidentally pass by, striking 

 them unseen from below and behind, much as does 

 P. azalea in the eastern Pacific (Hobson, 1968a, 

 1969). But whereas P. azalea usually aggregates 

 when hovering above the reef, P. goslinei usually 

 is solitary. No specimens of P. goslinei were col- 

 lected, but presumably it feeds on the mucus and 

 dermal tissue of its victim, as do other species of 

 this genus, including P. rhinorhynchus (Wickler, 

 1960). P. azalea (Hobson, 1968a), and P. town- 

 sendi (Springer and Smith- Vaniz, 1972). These 

 species are called sabre-toothed blennies because 

 each carries in its lower jaw a pair of enormous 

 fangs. Eibl-Eibesfeldt ( 1955) and Strasburg ( 1960) 

 believed that these fangs are used in feeding, but 

 Wickler (1960) concluded from work in aquaria 



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