AHLSTROM ET AL.: PLEURONECTIFORMES 



651 



Table 174. Numbers of Rays in Dorsal Crest and Size at Developmental Events in Paralichthyidae. 



along the ventral midline, and small melanophores on the trunk, 

 tail, ventral gut, pectoral fin, brain and lower jaw. During flexion 

 the entire body except for the caudal fin base becomes solidly 

 pigmented, a darker band forms forward of the caudal peduncle, 

 and the snout becomes heavily pigmented. 



Cilharuiae (Fig. 342). — Larvae of this family are known from 

 five specimens (4.0-8.0 mm) of Brachypleura novaezeelandiae 

 described by Pertseva-Ostroumova (1965). Notochord flexion 

 occurs between 5.0 and 7.0 mm and transformation at about 

 8.0 mm. Larvae have a moderately deep, thick body and a large 

 head with large jaws and eyes and about 10 large preopercular 

 spines; the sixth dorsal ray is elongate and the rays anterior to 

 it are assumed to be elongate, although damaged in all available 

 specimens; pelvic fins are elongate, extending beyond the anus; 

 pigment consists of a series of melanophores along the dorsum, 

 a series along the horizontal septum, and a postanal series along 

 the ventrum, melanophores below the gut, and on the pelvic 

 fin. 



Scophthalmidae (¥'\g. 343). — Larvae are known for 9 of the 10 

 species of this family. Petersen ( 1 909) described 5 of the 7 species 

 occurring in the eastern North Atlantic; Jones (1972) provided 

 excellent illustrations of the 2 species of eastern Atlantic Scoph- 

 thalmus and Bigelow and Welsh (1925) described larvae of 5. 

 aquosus. the only western Atlantic representative of the family. 

 Newly hatched larvae are 2.0-4.0 mm in length (Table 171); 

 size at notochord flexion for most species is 6.0-8.0 mm. Meta- 



morphosis can begin by 8 or 9 mm and be completed by 1 3 

 mm (S. aquosus. Phrynorhombus norvegicus, Zeugopterus 

 punctaius) or delayed to over 20 mm (S. maximus. S. rhombus). 

 Larvae are deep- and thick-bodied, especially at the gut, have 

 a large head and jaws and moderate to large eyes. Scophthalmid 

 larvae develop extensive head spination. Three species (Z. punc- 

 tatus, P. regius, Lepidorhoinbus whiffiagonis) develop paired 

 otic spines. In Z. punctatus, spines also develop at the lateral 

 aspect of the midbrain and on the opercle. Larvae of P. nor- 

 vegicus develop spines along the lower jaw, on the opercle and 

 preopercle, and at the shoulder (posttemporal region) while L. 

 boscii has preopercular spines and a shoulder cluster. S. ma.\- 

 imus and S. rhombus have a supraocular spiny ridge, numerous 

 spines on the opercle and preopercle and a shoulder cluster. 

 Pigmentation is heavy on the head and body in most species. 

 Z. pimctatus has a series of finfold bars and L. boscii develops 

 these and also incomplete bars on the body. Late larvae of all 

 species develop bars on the dorsal and anal fins. 



Paralichthyidae (Figs. 344, 345). — Three subgroups are recog- 

 nized in this family on the basis of adult characters: Paralichlhys 

 and relatives (Ancylopsella. Gaslropsella. Hippoglossina. Lio- 

 glosslna. Verecundum. Xystreurys): Pseudorhombus and rela- 

 tives (Cephalop.tetta. Tarphops): and Cyclopsetta and relatives 

 (Cltharlchthys. Eiropus. Syacium). 



In the first group larvae are known for species oi Paralichlhys 

 and Hippoglossina and for Xyslreurys liolepis and in the second 

 group larvae are known for Pseudorhombus and Tarphops. In 



