First (and only) Appearance: TBFGK Epilogue 13
Wanda was an orange spotted fish, one of Al Frappacino's pet fish living in the courtyard fountain of Aqua Velva. Jillian Zamussels croaked it for food, but was eventually persuaded to leave the fish alone and use Aqua Velva's food stores instead.
Some have speculated that Jillian's croaking of Wanda the fish may be foreshadowing a similar fate for Wanda Firebaugh.
Real World References
A Fish Called Wanda is a 1988 heist-comedy film.