Frogs

From Animal Crossing - Wiki on Neoseeker

The frog is a villager species that has appeared in every game of the series. They are defined by their large heads and their eyes on top of their heads.

Trivia

Gigi is the only frog that is new in Animal Crossing: City Folk.
Seven frogs have appeared in all of the Animal Crossing games.

Villager Species

Name	Games	Birthday	Picture Inscription
Camofrog	Animal Crossing Animal Crossing: Wild World Animal Crossing: City Folk	June 5th	"You can't see me."
Cousteau	Animal Crossing Animal Crossing: City Folk	December 17th	N/A
Drift	Animal Crossing Animal Crossing: Wild World Animal Crossing: City Folk	October 9th	"Always go for the gold!"
Emerald	Animal Crossing	Unknown	N/A
Frobert	Animal Crossing Animal Crossing: Wild World	February 8th	"I don't wanna see any lily-livered jumping! Always aim high!"
Gigi	Animal Crossing: City Folk	August 11th	N/A
Huck	Animal Crossing	Unknown	N/A
Jambette	Animal Crossing Animal Crossing: City Folk	October 27th	N/A
Jeremiah	Animal Crossing Animal Crossing: Wild World Animal Crossing: City Folk	July 8th	"Think about it man. Bull frog is only one letter away from blue frog"
Lily	Animal Crossing Animal Crossing: Wild World Animal Crossing: City Folk	February 4th	"Don't jump to conclusions!"
Prince	Animal Crossing Animal Crossing: City Folk	July 21st	N/A
Puddles	Animal Crossing Animal Crossing: Wild World Animal Crossing: City Folk	January 13th	"HIP HOP HO! Hey, let's go!"
Ribbot	Animal Crossing Animal Crossing: Wild World Animal Crossing: City Folk	February 13th	"Never rest, never rust."
Tad	Animal Crossing	Unknown	N/A
Wart Jr.	Animal Crossing Animal Crossing: Wild World Animal Crossing: City Folk	August 21st	"I've got my eye on you."