I didn't even realize you could Special Summon the same monster you discarded, but turns out you can. Pretty cool, looks like I need to go farm for a third FE.
No, you can not simply summon the discarded monster. You need to already have a dinosaur in your graveyard even before you activate the trap card.
Only possible way: Have a random dinosaur in your graveyard, then activate the trap card, discard Black Tyranno and now choose him to be summoned (as he is now part of the graveyard).
It's not like Black Tyranno's effect is that useful anyway. Any Spell/Trap on their field will stop it, and as long as you can destroy your opponent's Def. Pos. monsters with your weaker Dinos, you achieve the same result anyway. I've been trying out FE recently, and it's actually pretty solid. Nothing game changing, but still quite good.