NORTH AMERICAN SALMONIDAE 265 



B. Teeth on both head and shaft of vomer: supraethmoid short, width ine<liiini to broad, notched posteriorly; 

 latenil-line si-iilps ltKV-138 : anal fin rays !)-l(! ; all liave black body spots or siH-ckling but may also have light 

 spots or areas at some stages; fins without conspicuous white leading edge. 



Genus SALMO, Atlantic salmons and treats. 

 BB. Teeth on head (anterior end) of vomer only; supraethmoid long, narrow, with pKisterior projections: lateral- 

 line scales 109-131 ; anal fin rays 8-12 ; bo<ly siwts yellow to red or gray, never black ; no lateral body stripe ; 

 white leading edge on paired fins. 



C. Basibranchial (hyoid) teeth numerous and strong: supnilingual (tongue) teeth in parallel rows: pyloric 

 caeca 95-179 (average about 127-138) ; caudal fin deeply forked; pearl organs in adults: no bright colors, but 

 spotted with gray ; egg diameter less than 5.0 mm. ; lacustrine ; diploid chromosome nimiber 84. 



Genus CRISTIVOUER, lake trouts. 



CC. Basibranchial (hyoid) teeth few or missing, weak; supralingual (tongue) teeth form equal sides of an 



isdceles triangle; pyloric caeca 20-64 (average about 2S— 16. ,30-!)0 in N. tiiirculux) ; caudal fin very little to 



deeply forked; no pearl organs; brightly c<)lore<l in fresh water, spotted with yellow, pink, or red, lower fins 



usually brightly colored ; egg diameter usually more than 5.0 mm. ; adfluvial, fltivial, or optionally anadromous. 



Genus 8ALVELINU8, charrs. 



KEY TO SPECIES 



Salvelinus. Charrs 



A. Basibranchial (hyoid) teeth absent or rare: back with dark wavy "wormlike" verniiciilations extending onto 

 dorsal fin; lower fins with white front edge followed by a black stripe: tip of lower jaw black: some of lateral 

 spots may be pink or re<l with a blue halo; r<X)f of mouth black: end of caudal fin almo.<t square in adults; anal fin 

 falcate; diploid chromosome number 84; optionally anadromous, fluvial, or adfluvial: very shoi^ migrations in 



the sea j? Salvelinus fontinalis. Speckled eharr or eastern charr (eastern brook trout). 



AA. Basibranchial (hyoid) teeth usually present, weak to moderate: vernilculations on back ab.sent or faint: no 

 black stripe on lower fins : tip of lower jaw white to reddish : lateral si)<>ts without blue borders : caudal fin 

 slightly to well-forked Ln adults : optionally anadromous. adfluvial, or lacustrine. 



B. Pyloric caeca 20-39 (average about 28-29) ; numerous red dots on sides (-I-50) smaller than diameter of pupil; 

 pectoral fins very .seldom if ever with white anterior margin ; caudal fin almost square in adults ; optionally 



anadromous or fluvial; short migrations in the sea Salvelinus malma, dolly varden charr. 



BB. Pyloric caeca 20-99 (average about 38-46) : spots on sides orange: all lower fins with white anterior margin: 

 caudal fin well-forked ; optionally anadromous, adfluvial, or lacustrine. 



C. Maxillary extending about to pt>sterior margin of eye; lateral spots (orange or yellowish) very small and 

 numerous; roof of mouth white; white margin of lower flns narrow; adfluvial. 



Sah-elimts oquassa, blueback charr. 



Salvelinus o. marstoni, red Quebec charr. 



CC. Maxillary extending well beyond posterior margin of eye: orange or yellowish lateral spots small to large; 



broad white anterior edge on lower fins, roof of mouth white to blackish ; optionally anadromous or adfluvial ; 



.short migrations in the sea {alpinus) Salvelinus alpinus, Arctic charr. 



Salvelinus a. aureolus, golden charr or Sunapee charr. 



Salmo. Salmons and trouts 



A. Parr with small orange blotches or spots on sides adjac-ent to lateral line: black spots on caudal fin absent or 



few ; adults may have pink or blue halo surrounding black spots on body ; adult S. salar sehago may have some 



colored sjxjts ; caudal peduncle stout or slender, anal fin rays 9-11 (complete count). 



B. Teeth on head and shaft of vomer s-trong and well-develoi^ed ; branchiostegal rays average 10.0: oblique scale 

 rows 116-1.36; end of maxillary usually not far behind ix)sterior margin of eye: large black spots on body with 

 .-ionie often surrounded by pink or re<l halo: few smaller rertdish siMtts adjacent to lateral line: orange blotch 

 on adipose usually present even in sea-nni indi\iduals. no colored lateral band : tail never deeply forked, square 

 to fan-shaijed in older fish: tail unsi)otted : caudal peduncle stout: diploid chromosome number 80: optionally 

 anadromous, fluvial, or adfluvial: .short migrations in the sea Salmo trutta, brown trout. 



BB. Teeth on vomer all short weak; branchiostegal rays average 11.9; oblique scale rows 111-118; maxillary 

 extending to or slightly behind posterior margin of eye: small black si>ots, often x-shaped, numerous on upper 

 bofly, sometimes extending slightly onto rtor.-;al. adiiMise. and anal fins: landbx-ked varieties may have some 

 lighter spots on body: caudal i>eduncle slender: no colortMl lateral band; caudal usually without spots, caudal 

 slightly to well-forked in adults ; .some adults die after spawning ; diploid chromosome number 60 ; optionally 



anadromous or adfluvial; longTnigrations in the sea : not abundant far offshore Salmo salar. Atlantic sabnon. 



Salmo s. seltago, landlocked salmon. 



