• adipose fin is present
• the length of the base of the dorsal fin is greater than the length of the base of the anal fin
• back of the anal fin is vertical (straight up and down, not angled)
• no spots on dorsal fin
• weakly forked to square tail
• colouration includes light coloured spots (not parr) on darker side of fish (light spots on dark background)
• no spots on fins
  

Known distribution in Yukon: Central Yukon, headwaters of the Yukon, Liard and Peel River systems. Transplanted/stocked in some southern Yukon Lakes.

Other notable comments and clues:

• The most distinguishing feature of these fish is their distribution.
• Generally speaking, people field-classify this type of fish found in the Peel/MacKenzie River system as arctic char, while fish found in the Yukon River system are classified as dolly varden, and fish found in the headwaters of the Liard River are bull trout.
• Officially, the current understanding of the distribution of dolly varden and their cousins is: dolly varden are present in the Peel River system including upstream of Aberdeen Falls; arctic char are in the lower Peel system as well as dolly varden; dolly varden are present in some Yukon River tributaries that abut the Peel system, however only the Rackla is identified; bull trout are present in the Liard River system and in some Yukon River tributaries that abut the Liard (Swift and Jennings); dolly varden are present in some Alsek River tributaries.
• These three fish are so similar in their physical characteristics as juveniles you can only ID them genetically which means analyzing their genes in a laboratory environment. Take note of the area you sampled in as sometimes these fish are known to inhabit specific water systems.