664 



ONTOGENY AND SYSTEMATICS OF FISHES-AHLSTROM SYMPOSIUM 



Table 178. Size Data and Number of Elongate Dorsal Rays for Larvae of Symphurinae and Cynoglossinae. 



Cynoglossinae 



Cynogtossus ahbrevialus 

 (as Areliscus trigrammus 



3.2 



Fujita and Takila, 1965 



described several species from off west Africa. Life history seires 

 have been described for two achirine species of the western 

 North Atlantic, Trinectes maculatus and Achirus lineatus. Eggs 

 of achirines are smaller than in most soleines (Table 172) and, 

 accordingly, size at hatching is also smaller; achirines and some 

 soleines undergo notochord flexion and transformation at vei^ 

 small sizes (Table 1 77). Achirines are deep-bodied, with a large 

 gut that occupies a major portion of the body volume, a large 

 deep head with a distinct dorsal hump; eyes and jaws are large 

 (Fig. 356). Preflexion larvae of.-J. //«ea/M5 develop spinous ridges 

 above the eye (frontal bone), at the otic region (parietal and 

 autopterotic bones) and on the preopercle. Also, five rows of 

 papilla-like spines develop on the body. Larvae of T. maculatus 

 develop bony ridges on the frontal, parietal and autopterotic 

 bones. A. lineatus larvae are unique among described soleids in 

 having an elongate third dorsal ray. Early larvae of .-1. lineatus 

 are unpigmented but by late preflexion stage have developed 

 pigment on the head, gut, elongate dorsal ray, dorsal and ventral 

 body margins and blotches on the dorsal and anal fins. Early 

 larvae of T. maculatus are heavily pigmented and have three 

 large blotches in the dorsal finfold and two in the ventral finfold. 

 In later larvae these blotches become dusky bars that overlie 

 the nearly solid background pigment. 



Soleines have a large head and jaws as in achirines but the 

 eye is relatively smaller and the dorsal hump is less prominent 



(Fig. 356). Also, soleines are less deep-bodied and the gut oc- 

 cupies a relatively smaller portion of the body mass; in many 

 soleine species the rounded gut mass protrudes well beyond the 

 ventral profile. Pigmentation is highly varied ranging from species 

 of Aseraggodes which lack pigment to species such as Solea 

 solea. Pegusa lascans, Microchirus variegatus and Euryglossa 

 pan which are solidly covered with melanophores. A typical 

 pattern appearing in many described species consists of a series 

 of melanophores along the dorsum, ventrum and horizontal 

 septum, and melanophores on the head, gas bladder and fin- 

 folds (Fig. 356). 



Cynoglossidae {Fig. 357). — Two subfamilies, Symphurinae and 

 Cynoglossinae, are recognized in the family. The first larval 

 descriptions of the former are of Symphurus lacleus, S. ligulata 

 and S. pusilla (Kyle, 1913). Hildebrand and Cable (1930) de- 

 scribed a series as 5. plagiusa. but Olney and Grant (1976) 

 described a different series as S. plagiusa and pointed out that 

 Hildebrand and Cable's descriptions must refer to another 

 species. Pertseva-Ostroumova ( 1 965) ascribed a larval series to 

 S. orientalis and we have identified eggs and larvae of .S'. atn- 

 cauda. Larval series or metamorphosing specimens have been 

 ascribed to at least 1 1 types of cynoglossines; however, most of 

 these are incomplete series and identifications are tentative (Ta- 

 ble 178). Most cynoglossids are less than 2.5 mm at hatching; 



Fig. 353. Larvae of Pleuronectidae. (A) Glyptocephatus zachinis, 48.7 mm, redrawn from Ahlstrom and Moser, 1975; (B) G. stelleri. 24.6 

 mm, from Okiyama and Takahashi, 1976; (C) Tanakius kitaharai. 15.8 mm, ibid; (D) Microstomus achne. 8.8 mm, ibid; (E) Embassichthys 

 balhybius. 16.2 mm, from Richardson, 1981b. 



