You must learn a special skill to tame Lesser Dragonkin. For pets of this family other than cloud serpents, the skill is taught by the tome, How to Train a Dragonkin. This is awarded by Kaestrasz in Valdrakken at renown level 23 with the Valdrakken Accord. It is only awarded to hunter characters with the appropriate renown, you cannot achieve the renown on a non-hunter alt.
Appearance:
Location:
Located in Viridescent Thicket, The Emerald Dream.