Snow Spider, Small (CR 1/2)

Small Vermin
Alignment: Always neutral
Initiative: +4 (Dex); Senses: darkvision 60 ft., tremorsense 60 ft., and Spot +8

AC: 15 (+1 size, +4 Dex), touch 15, flat-footed 11
Hit Dice: 1d8 (4 hp)
Fort +2, Ref +4, Will +0
Speed: 30 ft., climb 30 ft.
Space: 5 ft./5 ft.
Base Attack +0; Grapple -6
Attack: Bite +5 melee
Full Attack: Bite +5 melee
Damage: Bite 1d4-2 plus poison
Special Attacks/Actions: Leap, poison
Abilities: Str 7, Dex 18, Con 11, Int -, Wis 10, Cha 2
Special Qualities: vermin traits
Feats: Spring Attack; Weapon Finesse
Skills: Climb +12, Hide +12~, Jump +24, and Spot +8
Advancement: -
Climate/Terrain: Cold marshes
Organization: Colony (2-5) or nest (6-11)
Treasure: None

Source: Frostburn

This big spider is covered in tufts of stiff white hair and has eight pale blue eyes. Its huge fangs are tucked beneath its horrible head.

Snow spiders are aggressive hunting spiders that roam the tundra, bogs, and everfrost of cold regions. They paralyze their prey for later consumption.