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Fishery Bulletin 90(2), 1992 



abundance for Norwegian flatfishes. However, during 

 the present study, some individuals had full and gorged 

 stomachs, filled only with either polychaetes or prawns. 

 This might indicate either greater availability or patchy 

 distribution of the major food items. Seshappa and 

 Bhimachar (1955) reported for Malabar sole Cyno- 

 ghssus semifasciatiis, from the west coast of India, that 

 during certain months the guts were gorged with only 

 one prey, mostly polychaetes. 



During the present investigation, most stomachs of 

 C. arel and C. lida were found to contain considerable 

 quantities of sediment (sand and mud). In some speci- 

 mens, the entire stomach was filled with sediment. 

 Algal filaments were also found in some stomachs. 

 Sediment and algal filaments were probably ingested 

 accidentally with bottom-living polychaetes and other 

 infauna. Since demersal fishes browse near the sea 

 bottom, some amount of sediment may frequently be 

 in their gut. This has been reported for other flat- 

 fishes, such as Malabar sole Cynoglosstis semifasciatics 

 (Seshappa and Bhimachar 1955) and C. lingua (Kutha- 

 lingam 1957), and for other demersal fishes (Sedberry 

 and Musick 1978). Stickney (1976) stated that the high 

 percentage occiu-rence of sand in the stomachs of 

 blackcheek tonguefish Symphurus -plagiusa might be 

 due to ingestion of a significant quantity of detrital 

 material in its feeding activities. It is unknown if sedi- 

 ment ingestion in C. arel and C. lida is accidental or 

 represents a deliberate feeding action. In situ or 

 aquarium studies on feeding habits would be required 

 to answer this question. 



Nematodes, present in stomachs of several specimens 

 of C. arel and C. lida, were not attached to the stomach 

 wall but, rather, appeared to be free-living species. 



age from growth to reproduction, so that the rate of 

 growth in males is reduced at an earlier age than in 

 females. Results of age and growth studies on yellow- 

 tail flounder Limandaferruginea from New England 

 (Lux and Nichy 1969), Limanda herzensteini from 

 Japan (Wada 1970a), Agulhas sole Aicstroglossus pec- 

 toralis from South Africa (Zoutendyk 1974a), and Solea 

 solea from Spain (Ramos 1982) are also consistent with 

 Pitt's view. In contrast to the above view, no signifi- 

 cant difference was observed between the growth 

 patterns in males and females of C. lida. 



It is important to know at what age fishes are 

 recruited to the fishery. The present study reveals that 

 C. arel and C lida reach commercial size during their 

 2d and 3d year. Botha et al. (1971) stated that Agulhas 

 sole Austroglossiis pectoralis off South Africa reached 

 commercial size during their 3d-5th years, and at 

 certain times their 2d-4th years. Lux and Nichy (1969) 

 observed that yellowtail flounder Limandaferruginea 

 of the New England fishing grounds recruited to the 

 commercial fishery during their 3d and 4th years. Ac- 

 cording to Seshappa and Bhimachar (1955), the bulk 

 of commercial catches of Malabar sole Cynoglossus 

 semifasciatus consisted of 2d-year individuals. 



Cynoglossus arel and C. lida have a life-span of a little 

 over 3 years in the southeast coast of India. The 

 longevity for C. lida from the west coast of India has 

 also been reported to be 3-4 years (Seshappa 1978). 

 Longevity in most tropical fish species is relatively 

 shorter and seldom exceeds 2-3 years (Qasim 1973b). 

 However, temperate flatfishes were reported to have 

 a longevity of 6-30 years (Devoid 1942, Arora 1951, 

 Pitt 1967, Lux and Nichy 1969, Lux 1970, Wada 1970a, 

 Zoutendyk 1974a, Smith and Daiber 1977). 



Age and growth 



In the present study, distinct annual markings were 

 not seen in scales, otoliths, opercular bones, and 

 supraoccipital crests of C. arel and C. lida. Struhsaker 

 and Uchiyama (1976) have stated that tropical and sub- 

 tropical fishes are difficult to age, because they general- 

 ly experience little seasonal and environmental changes 

 and so do not develop annual rings clearly. 



It was observed in C. arel and C. lida that after very 

 rapid growth during the first year, there is a consid- 

 erable reduction in the growth rate during the years 

 when sexual maturity sets in; afterwards, the growth 

 rate decreases slightly with age. This observation is 

 consistent with the findings of Ford (1933) and Devoid 

 (1942). 



Females of C. arel show faster growth, compared 

 with males, and also live longer. According to Pitt 

 (1966, 1967), since males mature earlier than females, 

 it seems likely that energy is diverted at an earlier 



Length-weight relationships 



During the present analyses, C. arel showed differ- 

 ences in characteristic length-weight slopes for males 

 and females. Similar observations were made by 

 Ketchen and Forrester (1966) and Powles (1967), while 

 analyzing the length-weight relationships of Petrale 

 sole Eopsetta jordani and American plaice Hippoglos- 

 soides platessoides, respectively. However, C. lida 

 showed no significant differences in characteristic 

 length-weight slopes for males and females. Zoutendyk 

 (1974b) on Agulhas sole Austroglossvs pectoralis, and 

 Smith and Daiber (1977) on summer flounder Para- 

 lichthys dentatus, did not report significant differences 

 in length-weight characteristics of males and females. 

 Cynoglossus arel and C. lida showed significant 

 regression coefficients (b-values), which differed 

 significantly from the hypothetical B value ( = 3). Webb 

 (1972) made similar observations for yellow-bellied 

 flounder Rhombosolea leporina. 



