Because the spell beast shape I is a spell of the polymorph subschool, the only attacks that are gained from the spell are natural attacks:
[Y]ou gain any of the natural attacks of the base creature, including proficiency in those attacks. These attacks are based on your base attack bonus, modified by your Strength or Dexterity as appropriate, and use your Strength modifier for determining damage bonuses.
A caster that uses beast shape I to assume a form that has more than one natural attack can use all of those attacks during as a full attack action (but no iterative attacks when employing them), using the caster's base attack bonus as described above.
Unfortunately for the caster, the game defines carefully natural attacks:
Most creatures possess one or more natural attacks (attacks made without a weapon). These attacks fall into one of two categories, primary and secondary attacks. Primary attacks are made using the creature’s full base attack bonus and add the creature’s full Strength bonus on damage rolls. Secondary attacks are made using the creature’s base attack bonus –5 and add only 1/2 the creature’s Strength bonus on damage rolls.
...And so on. There's a table, and tongue, fiery body (a supernatural ability), and bone spikes aren't on it.
You can learn more about natural attacks in Pathfinder from this question, this question, this question, this question, and probably others. (Apparently, Pathfinder should make this topic a little clearer.)