On these two pages, you will see all the Biomorph Enhancements available to the majority of the Tyranids. Beneath the image and title of the enhancement you will find a short paragraph entitled "What It Does." This text contains an abbreviated rule about how this enhancement works on the tabletop. For a more detailed description, turn to pp.32-33 of Codex: Tyranids.

Acid Maw

What It Does.
A creature with an Acid Maw may reroll unsuccessful rolls to Wound in the 1st round of a close combat.

Adrenal Gland
What It Does:
Adrenal Glands add +1 to a creature's Weapon Skill or Initiative characteristics.
Bio-Plasma*
What It Does:
Creatures with Bio-Plasma may make a single extra close-combat Attack, worked out at double the model's Initiative.
Bonded Exoskeleton
What It Does:
A creature with a Bonded Exoskeleton gains +1 Toughness.
Enhanced Senses
What It Does:
Creatures with Enhanced Senses gain +1 Ballistic Skill.
Extended Carapace
What It Does:
A Tyranid with an Extended Carapace gains +1 to its Armor save, so a Tyranid with a 5+ Armor save will instead have a 4+ Armor save, and so on.
Feeder Tendrils*
What It Does:
A creature with Feeder Tendrils always counts as having the Preferred Enemy unit special rule. Any Tyranid brood with a model within 2" of the creature also benefits from this special rule.
Flesh Hooks*
What It Does:
A creature with Flesh Hooks counts as being equipped with frag grenades in close combat. Creatures with Flesh Hooks count "vertically impassable" terrain as Difficult Terrain instead.
Implant Attack*
What It Does:
A model that does not save a Wound from a creature with an Implant Attack suffers 2 Wounds instead of 1. Implant Attacks are effective only in close combat and have no effect on Wounds inflicted by Bio-Plasma.
Leaping
What It Does:
Leaping creatures gain a Fast Charge of 12", though they do not become Beasts. A creature with Leaping may make its full Attacks when within 3" of a friendly model in base contact rather than the usual 2".
Mace Tail*
What It Does:
The creature may make a special close-combat Attack each turn if more than four enemy models are in base contact with it at the beginning of that Assault Phase. These Attacks are conducted at Initiative 1 at the creature’s full Strength.
Scythe Tail*
What It Does:
The creature may make a special close-combat Attack each turn if more than four enemy models are in base contact with it at the start of that Assault Phase. These D3 Attacks are at Initiative 1 at half the creature’s Strength (round down).
Acid Maw through Scythe TailRegenerate through Winged

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