Pokemon give an amount of EPs depending on their stage in a line. For example:
Bulbasaur 1sp.Atk
Ivysaur 1sp.Atk 1sp.Def
Venusaur 2sp.Atk 1sp.Def
1 2 3
3 is max. and 1 min.
Chansey always gave 2 EP despite being the 1st in it's evolutionary line.
Gen 4 arrives
Oh, hi Happiny
The following is a list of Pokemon which give more than 1 EP altough they're the 1st stage of their line:
Kangaskhan 2 HP
Pinsir 2 Atk (despite Scyther giving 1)
Tauros 1 Atk 1 Spe
Lickitung 2 HP (Lickilicky 3 HP)
Lapras 2 HP
Aerodactyl 2 Spe
Girafarig 2 S.Atk (Stantler which seems like the same league gives 1)
Heracross 2 Atk
Corsola 1 Def 1 S.Def
Skarmory 2 Def (like Mantine, who got a pre-evo)
Miltank 2 Def
Sableye 1 Atk 1 Def
Mawile 1 Atk 1 Def
Torkoal 2 Def
Zangoose 2 Atk
Seviper 1 Atk 1 S.Atk
Solrock 2 Atk
Lunatone 2 S.Atk
Tropius 2 HP
Absol 2 Atk (Chimecho too, got pre-evo)
Relicanth 1 HP 1 Def
Carnivine 2 Atk
I left out stuff that surely won't have a pre-evo like Unown, but maybe missed some