Jordan and Evermann, — Fishes of North America. 2007 



II.— PLEURONECTIN^. 



(Flounder Tribe.) 



Month small, unsymmetrical, the Jaws on the eyed side with nearly 

 straight outline, the bones on the blind side strongly carved; dentition 

 chiefly developed on the blind side; eyes large; edge of preopercle not 

 hidden by the scales; pectoral fins well developed; vertical fins well 

 separated; ventral fins nearly or quite symmetrical, that of the eyed side 

 not prolonged along the ridge of the abdomen ; anal spine usually strong 

 (obsolete in Microstoiiius and Embassichthys). Body dextral (except fre- 

 quently in Platichthys stellatus). Species arctic or subarctic in distribution. 



a. Vertebra} in moderate number, from 10 + 26 = 36 to 11 +33=: 44; dorsal rays 65 to 

 80; anal rays 45 to GO. 

 b. Teeth small, acute, in several series; lateral Hue nearly straight, with an acces- 

 sory dorsal branch; lower pharyngeals narrow, with small biserial teeth; 

 scales cycloid, 

 c. Lips thick, eiich with several longitudinal folds; dorsal tin beginning on 

 the blind side; vertebri© 38 to 40. Pleuronichthys, 1029. 



cc. Lips simple; dorsal tin beginning on the median line; vertebras (in H.gut- 

 tvlata) 11 + 24 = 35. Hypsopsetta, 1030. 



66. Teeth chietly uuiserial, all more or less blunt, conical or incisor-like. 

 d. L.ateral line with an accessory dorsal branch. 

 e. Lateral line withoiit distinct arch in front. 

 /. Teeth compressed, incisor-Uke, close set. 



g. Scales closely imbricated, mostly cycloid; upper eye on 



median line; vertebrae (in P. vetulus) 11 + 33 = 44. 



^ Pakophrys, 1031. 



gg. Scales scarcely imbricated, all very strongly ctenoid ; eyes 



both lateral. Inopsetta, 1032 



ff. Teeth conical, separated, not incisor-like ; scales closely imbri 



Gated, all strongly ctenoid ; mouth comparatively large (ap 



preaching that of Psettiehthys) ; vertebra* (in /. Isolepis) 10+ 



32 =: 42. IsopsETTA, 1033 



ee. Lateral line with a distinct arch in front; scales imbricated, rough 



ctenoid; vertebrae (in L.bilineata) 11 + 29 = 40. 



LEPmOPSETTA, 1034 



dd. Lateral line without accessory dorsal branch. 



h. Lateral line with a distinct arch in front; scales imbricated, rough 

 ctenoid; vertebrae (in i. Zi)/i«»da) about 40. Limanda, 1035 



hh. Lateral line without distinct arch in front. 



i. Scales regularly imbricate, all (on eyed sidef ctenoid in both 

 se.xes ; no stellate tubercles on head nor on bases of dorsal 

 and anal fins; teeth, incisor-like, close set; lower pharyn- 

 geals very narrow, each with 2 rows of separate, conical 

 teeth; fin rays scaly. Pseudopledronectes, 1036. 



ii. Scales imperfectly imbricated, or else not all ctenoid. 



j. Scales chiefly cycloid in both sexes ; lower pharyngeals 

 small and narrow, separate, each with about 1 row of 

 small, bluntish teeth ; teeth incisor-like, close set, 

 forming a cutting edge; no stellate scales at base of 

 dorsal and anal. Pleuronectes, 1037. 



jj. Scales rough ctenoid in the male, more or less cycloid in 

 the female (fin rays scaly in the male, naked in the 

 female) ; lower pharyngeals very large, more or less 

 united in the adult, their surface somewhat concave, 

 the teeth in 5 or 6 rows, large, blunt, close set; teeth 

 in jaws incisor-like; flu rays of dorsal and anal with- 

 out tubercles at base. Liopsetta, 1038. 



