n large beast ethereal 

Perception +12; darkvision

Languages Aklo

Skills Athletics +12, Stealth +15

Str +5 Dex +4 Con +3 Int -2 Wis +1 Cha +7

AC  21; Fort +12, Ref +15, Will +10

HP 75

Speed 40 feet, climb 20 feet

Melee [>] fangs +15 (magical), Damage 1d10+7 piercing plus ether spider venom and Grab

Ranged [>] web +14 (magical, range increment 30 feet), Effect ethereal web trap

Ether Spider Venom (poison) Saving Throw DC 22 Fortitude; Maximum Duration 6 rounds; Stage 1 1d6 poison damage and clumsy 1 (1 round); Stage 2 2d6 poison damage, clumsy 2 and slowed 1 (1 round); Stage 3 3d6 poison damage, clumsy 3 and slowed 2 (1 round)

Ethereal Step [>] The ether spider shifts to either the Ethereal Plane or the Material Plane. The ether spider can remain on the Ethereal Plane indefinitely without ill effect. While there, it can see clearly onto the Material Plane with a range of 60 feet. On its first round in an encounter, the ether spider can use this ability once as a free action.

Ethereal Web Trap A creature hit by the ether spider's web attack is immobilized and stuck to the nearest surface (Escape DC 22).

Web Burst [>>] Frequency once per day; Effect The ether spider flings a gout of stored webs in a 30-foot cone. These webs can pass between the Material Plane and the Ethereal Plane. Each creature in the area is immobilized, as ethereal web trap, unless it succeeds at a DC 22 Reflex save.

Bestiary, page 155.