All the pet species Dittoed needs to complete:

Addow
Arinya (Limited Edition)
Astro (Limited Edition)
Azul
Basil (Limited Edition)
Bolimo
Chibs (Limited Edition)
Crikey (Limited Edition)
Crindol
Daisy (Restricted)
Dakota (Limited Edition)
Decadal (Retired Restricted)
Doyle
Echlin (Restricted)
Equilor
Ercuw (Limited Edition)
Eyru (Limited Edition)
Fasoro
Feliz
Figaro (Restricted)
Flab
Gizmo (Limited Edition)
Gobble (Restricted)
Gonk
Grint
Hump (Restricted)
Huthiq (Limited Edition)
Ideus
Ike (Limited Edition)
Jessup
Justin (Restricted)
Kaala
Kidlet
Knutt
Kronk (Limited Edition)
Kujo (Limited Edition)
Lati (Limited Edition)
Leido
Limax (Restricted)
Lorius (Limited Edition)
Mordo (Limited Edition)
Murfin
Newth
Nino (Limited Edition)
Oglue (Limited Edition)
Osafo
Paffuto
Phanty (Limited Edition)
Poera (Limited Edition)
Pucu (Limited Edition)
Quell (Limited Edition)
Raulf (Restricted)
Reese
Renat
Rofling (Limited Edition)
Rusty (Limited Edition)
Sindi (Limited Edition)
Snookle (Limited Edition)
Speiro
Straya (Restricted)
Sybri (Restricted)
Tantua
Tasi (Limited Edition)
Troit ( Limited Edition)
Ushunda (Limited Edition)
Viotto (Limited Edition)
Vixen (Restricted)
Vlad (Restricted)
Walee
Wallop (Restricted)
Willa (Restricted)
Xoi
Yakubi
Yuni (Limited Edition)
Zetlian
Zoink (Limited Edition)
Zola (Restricted)
Zoosh