Originally Posted by flink

It also depend on the type.


I can also confirm that.

For the event boss, the rewards are as follow:
Dummer Bee => (Lv + 9) Dahma Nactar Spheres
Nemura Dummer Bee => (Lv + 19) Dahma Nactar Spheres

The Seedy Seed and the Queen Wasp gives the same amount of equipment seed for the same level.
(but it's not linear)
The Scoll Scoville gives much more equipment seed for the same level.

Thanks for clearing that confusion. I thought it was all random. I recorded some but I lost track.