icks ▁ ▁Gem st ones ▁ ▁Mo ▁E azy ▁Son orous ▁ ▁References ▁▁ ▁Category : N iger ian ▁drama ▁television ▁series ▁Category : 2 0 1 7 ▁Niger ian ▁television ▁series ▁deb uts <0x0A> </s> ▁The ▁New ▁Zealand ▁gray ling ▁( Pro tot ro ct es ▁o xy rh yn chus ) ▁is ▁an ▁ext inct ▁sm elt ▁of ▁the ▁genus ▁Pro tot ro ct es , ▁which ▁was ▁found ▁only ▁in ▁low land ▁rivers ▁and ▁streams ▁of ▁New ▁Zealand . ▁They ▁were ▁an ▁am ph id rom ous ▁species — sp aw ning ▁in ▁fresh water ▁streams ▁and ▁developing ▁to ▁m atur ity ▁in ▁salt water . ▁Their ▁length ▁was ▁between ▁ 2 0 ▁and ▁ 4 0   cm . ▁ ▁Though ▁abund ant ▁through ▁the ▁early ▁colonial ▁period , ▁by ▁the ▁ 1 8 7 0 s ▁their ▁population ▁had ▁decl ined . ▁The ▁last ▁known ▁spec imen ▁was ▁caught ▁in ▁the ▁late ▁ 1 9 2 0 s ▁to ▁early ▁ 1 9 3 0 s . ▁De for est ation ▁and ▁pred ation , ▁competition ▁and ▁disease ▁from ▁introduced ▁tr out ▁likely ▁led ▁to ▁the ▁New ▁Zealand ▁gray ling ' s ▁ext inction . ▁The ▁impact ▁of ▁introduced ▁dise ases ▁from ▁tr out ▁has ▁a ▁parallel ▁in ▁Australia , ▁where ▁utter ly ▁immense ▁fish ▁k ills ▁of ▁the ▁closely ▁related ▁Australian ▁gray ling ▁were ▁caused ▁by ▁introduced ▁stra ins ▁of ▁S ap ro leg nia ▁shortly ▁after ▁w ides p read ▁tr out ▁stock ing ▁comm enced