Scarab Beetle, Giant (CR 2)

Large Magical Beast
Alignment: Always neutral
Initiative: -1 (Dex); Senses: darkvision 60 ft., Listen +2, and Spot +2

AC: 12 (-1 size, -1 Dex, +4 natural), touch 8, flat-footed 12
Hit Dice: 5d10 (37 hp)
Fort +6, Ref +3, Will +1
Speed: 20 ft., burrow 5 ft.
Space: 10 ft./5 ft.
Base Attack +5; Grapple +12
Attack: Bite +7 melee
Full Attack: bite +7 melee
Damage: Bite 1d8+3
Special Attacks/Actions: Flare
Abilities: Str 16, Dex 9, Con 15, Int 1, Wis 10, Cha 9
Special Qualities: glide, immune mind-affecting effects
Feats: Alertness; Skill Focus (Jump)
Skills: Jump +46 (includes a +40 racial bonus), Listen +2, and Spot +2
Advancement: 6-9 HD (Large), 10-15 HD (Huge)
Climate/Terrain: Any underground
Organization: Solitary, pair, or herd (8-20)
Treasure/Possessions: None

Source: Dungeon #134

Flare (Su): As a move action, scarab beetles can use their wings to ignite the phosphorescence in their abdomens, generating an intense light. In addition to illuminating the area around the beetle within a 150-foot radius, the light dispels all magical darkness effects within 20 feet that originate from spells up to 2nd level. The searing light also causes 1d6 points of damage per round to any undead or creature from the plane of shadow (such as shadow mastiffs) within 20 feet. A scarab beetle's flare lasts for one round per HD, after which the scarab beetle undergoes a refractory period of 1d4 rounds before it can flare again. As it uses its wings to propel the flare, a scarab beetle loses its racial bonus to jump checks and its glide ability while its flare is active.

Glide (Ex): A giant scarab beetle cannot fly, however its wings give it a +40 racial bonus on jump checks. In addition, any time it falls more than 10 feet it is entitled to a DC 15 Reflex save. Success halves the damage from a fall of any height.