Don't ask how I even stumbled upon this...All I will say is curiousity. Freaks me out just looking at it.. but it is called a fissured tongue or lingua plicata.  It is a familial, but not always a congenital condition. The fissures are of variable depth and usually extend laterally from a median groove.   It is an asymptomatic condition, unless food particles and debris lodging in the depths of the fissures cause a mild glossitis...You're welcome.