Salamanders and attacks of opportunity

[Gnarnia]

Salamanders (http://www.d20srd.org/srd/monsters/salamander.htm) have a tail whip attack that can be used as a secondary attack in concert with manufactured weapon attacks (the manufactured weapon attacks are primary / iterative).

It's their only natural weapon though, so is it actually a primary attack that's relegated to use as a secondary attack when wielding natural weapons? They don't have a claw attack or anything.

I ask because their tails have a 10' natural reach (for average salamanders), but their melee weapons have a 5' reach. Attacks of opportunity need to be made with one's primary weapon, so can a salamander use their tail to take an ATOO against someone who moves into and out of that square 10' distant?

Salamander nobles (on the same page) sometimes use longspears specified with a 20' reach (same as their tails). Can they make the choice to use their spear or their tail for the ATOO?

[Flickerdart]

I can find no rule requiring you to use only primary weapons for an AoO.

[Gnarnia]

Hmmm, looks like I misread it in the "reading the monster entries" page in srd (the in most cases being the important part).

http://www.d20srd.org/srd/monsters/intro.htm it has this

"Attack
This line shows the single attack the creature makes with an attack action. In most cases, this is also the attack the creature uses when making an attack of opportunity as well. The attack line provides the weapon used (natural or manufactured), attack bonus, and form of attack (melee or ranged). The attack bonus given includes modifications for size and Strength (for melee attacks) or Dexterity (for ranged attacks). A creature with the Weapon Finesse feat can use its Dexterity modifier on melee attacks. If the creature uses natural attacks, the natural weapon given here is the creature’s primary natural weapon. If the creature has several different weapons at its disposal, the alternatives are shown, with each different attack separated by the word "or." A creature can use one of its secondary natural weapons when making an attack action, but if it does it takes an attack penalty, as noted in the Full Attack section below. The damage that each attack deals is noted parenthetically. Damage from an attack is always at least 1 point, even if a subtraction from a die roll reduces the result to 0 or lower."

Digging around, I also found this https://www.wizards.com/default.asp?x=dnd/glossary&term=Glossary_dnd_naturalweapon&alpha= which says "Attacks with secondary natural weapons are less effective and are made with a -5 penalty on the attack roll, no matter how many there are. (Creatures with the Multiattack feat take only a -2 penalty on secondary attacks.) This penalty applies even when the creature makes a single attack with the secondary weapon as part of the attack action or as an attack of opportunity."

So it looks like they do have the option of using their tails for the ATOO when it's more beneficial.

[KillianHawkeye]

Not 100% sure, but I wouldn't think that their tail would continue to be a secondary weapon when it's not their turn. It only becomes that when they also attack with their main weapon, after all.