Fulminating Crab (Zap Crab) (CR 1)

Small Vermin (Aquatic)
Alignment: Always neutral
Initiative: +0; Senses: darkvision 60 ft. and Spot +8

AC: 14 (+1 size, +3 natural), touch 11, flat-footed 14
Hit Dice: 1d8+3 (7 hp)
Fort +2, Ref +0, Will +0
Speed: 20 ft., burrow 5 ft., swim 10 ft.
Space: 5 ft./5 ft.
Base Attack +0; Grapple -6
Attack: 2 claws -1 melee
Full Attack: 2 claws -1 melee
Damage: Claw 1d4-2
Special Attacks/Actions: Bioelectrical shock, improved grab, psionics, squeeze
Abilities: Str 7, Dex 11, Con 11, Int --, Wis 10, Cha 4
Special Qualities: immunity to electricity, vermin traits
Feats: Toughness (B)
Skills: Hide +12, Spot +8, Survival +3, and Swim +10
Advancement: 2-3 HD (Medium-size)
Climate/Terrain: Temperate and warm aquatic and marsh
Organization: Colony (2-5) or herd (6-11)
Treasure: None

Source: Web

Fulminating crabs (also known as zap crabs) are relatively peaceful scavengers that use psionic powers to protect themselves from larger creatures. They prefer to stay in the water, but they sometimes venture onto the shore in search of food.

A zap crab looks like a large crab with a dull blue shell and a white underside. When frightened, small electrical discharges crackle between its claws. Psionic gourmets consider zap crabs a delicacy.

Aquatic Subtype

Creatures with the aquatic subtype always have swim speeds and thus can move in water without making Swim checks. An aquatic creature can breathe underwater. It cannot also breathe air unless it has the amphibious special quality.