The Japanese name of this monster is most likely a reference to 'pteranodon', a genus of flying reptiles that could have a wingspan of over 7 meters in the larger species. They lived during late Coniacian to early Campanian stages of the Cretaceous period, and most likely lived on offshore rookeries from which they ranged over sea and land and fed on various fish.
Pterodactyls, or more properly Pterodactylus, is another genus of flying reptiles of the order Pterosauria. They were much smaller, having a wingspan of only around 1 meter, and fed on fish and small land animals.
プテラノゴン [pteranogon] in Japanese.
Final Fantasy III

Level: 33, Number: 129, Type: Flying, Family: Pterodactyl
HP: 1,570, ATK: 68, DEF: 25, MDEF: 6, STR: 32, VIT: 30, INT: 25, MND: 28, AGI: 30, WGT: 11
GIL: 640 / EXP: 3,280
Immunity: Mini, Toad
Weakness: Wind 50%, Piercing 50%
Resistance: Earth 50%
Abilities: Attack (uses with 100% chance), attacks once per round
Drops: Hi-Potion ~2.9%, Phoenix Down ~0.1%
Steal: Hi-Potion (99.8% @ THF99)
Place: Temple of Time
Drop Rate: 3%
Drop Table: 1 Hi-Potion, 2 Hi-Potion, 3 Hi-Potion, 4 Hi-Potion, 5 Hi-Potion, 6 Hi-Potion, 7 Hi-Potion, 8 Phoenix Down
Category: Bestiary