▁any ▁other ▁fish . ▁ ▁Minn ows ▁can ▁be ▁hard ▁to ▁distinguish ▁because ▁many ▁look ▁al ike . ▁ ▁All ▁min n ows ▁have ▁one ▁d ors al ▁fin , ▁vent ral ▁fins ▁near ▁the ▁an us , ▁a ▁later al ▁line ▁system ▁( in ▁most ▁species ), ▁and ▁smooth , ▁round ▁cy clo id ▁scales . ▁ ▁Their ▁j aws ▁lack ▁teeth , ▁but ▁they ▁have ▁one ▁to ▁three ▁rows ▁of ▁ph ary n ge al ▁teeth ▁to ▁gr ind ▁food . ▁ ▁Def ining ▁physical ▁characteristics ▁such ▁as ▁the ▁number ▁and ▁type ▁of ▁fin ▁ray s , ▁type ▁of ▁scales , ▁and ▁pattern ▁of ▁ph ary n ge al ▁teeth ▁are ▁used ▁to ▁distinguish ▁min n ows . ▁ ▁Silver j aw ▁min n ows ▁have ▁a ▁head ▁with ▁a ▁flat ▁unders ide ▁and ▁large ▁sil very - white ▁ch amb ers ▁on ▁the ▁sides ▁that ▁form ▁their ▁complete ▁later al ▁line ▁system . ▁Since ▁these ▁fish ▁are ▁relatively ▁small , ▁ 2 - 3 ▁inches ▁in ▁length , ▁large ▁numbers ▁can ▁exist ▁in ▁a ▁small ▁area ▁and ▁still ▁find ▁necessary ▁resources . ▁ ▁They ▁are ▁native ▁to ▁many ▁streams ▁and ▁rivers ▁in ▁the ▁United ▁States ▁in ▁a ▁dis j unct ▁distribution . ▁ ▁Phys ical ▁description ▁ ▁The ▁silver j aw ▁min now ▁has ▁a ▁later al ▁line ▁system ▁with ▁many ▁distinct ive ▁sil very - white ▁por es ▁connecting ▁to ▁an ▁internal ▁canal ▁that ▁helps ▁the ▁fish ▁detect ▁pre y . ▁ ▁One ▁key ▁feature ▁of ▁all ▁min n