Summon Thanadaemon

Conjuration (Summoning) [evil]
Level: Cleric */Oracle * 9, Sorcerer */Wizard * 9, Warlock * 9
Components: V, S, F (two silver coins)
Casting Time: 1 round
Range: close (25 ft. + 5 ft./2 levels)
Effect: one summoned creature
Duration: 1 round/level (D)
Saving Throw: None
Spell Resistance: no
  This spell functions like summon monster, except it summons a single thanadaemon. You can only use this spell in an area with enough open water to accommodate the daemon's skiff, or when on the Astral Plane or Ethereal Plane.