You do not gain any extraordinary special attacks or special qualities not noted above under physical qualities, such as darkvision, low-light vision, blindsense, blindsight, fast healing, regeneration, scent, and so forth.
Not everyone agree on what you get from Alter self.
Personally, I do not get the bold part of the sentence. Physical Qualities are, as far as I know, never defined anywhere and there is no Physical Qualities part on a stat block. Special Attacks and Special Qualities are the only existing ones.
So, do you get anything? Nothing? And if you do get something, what do you get?
Let's take examples. (And pretend we are the right type in order to take these forms)
- Flamebrother, Salamander: Under special Attacks, you have Constrict, Heat and Improved grab. Do you get any of these? They all are, under the COMBAT part of the creature's stat block, and listed as (Ex)traordinary.
- Aranea: Special Attacks, Poison, Spells, Web. Obviously we are not getting spells. But what about poison and web? They are listed in the attack routine of the monster after all.
- Lantern Archon: Its attack is neither under Special Attacks or Special Qualities but only under COMBAT or directly under Attack or Full Attack. What does that mean? If you do not get ANY (Ex) attacks or special attacks, you would be unable to attack as a Lantern Archon?