Tiny Beast, unaligned
Armor Class 13
Hit Points 2 (1d4)
Speed swim +30, walk +30
Challenge 1/8
Senses blindsight 10 ft., passive Perception 10
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 1 piercing damage, and the target must make a DC 10 Constitution saving throw, taking 5 (2d4) poison damage on a failed save, or half as much damage on a successful one.
Source: 5e Core Rules · OGL/Open