Wrath:
(1)EoE: Malygos
(4)Vault of Archavon: Archavon, Emalon, Koralon, Toravon
(15)Naxx
(1)OS: Satharion
(14)Ulduar
(5)TotC
(1)Onyxia
(12)ICC
(1)RS: Halion
Wrath Total: 54 raid bosses (16 off them basicly reused)
Legion:
(15)Broken isles world bosses
(7)Emerald Nightmare
(3)Trial of Valor
(10)Nighthold
(9)Tomb of Sargeras
(11)Antorus
(6)Invasion points
Legion Total: 61, no reused(possibly more, realisticly its all we get)
Edit:
Cata:
(3)Baradin Hold
(6)Blackwing Descent
(4)Bastion of Twilight
(2)Throne of the four Winds
(7)Firelands
(8)Dragon Soul
Cataclysm Total: 30