Critters III! Now also in 5e!

[Metastachydium]

http://fxb.worth1000.com/entries/585079/cowbird

Pterotaurs for the win!

Molothrus bos

Might I suggest boviceps ('cattle-headed') instead of bos?

Hero Shrew

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Special Qualities: Darkvision 60 ft., DR 5/-, Immune to Fear, Superhero, Energy Resistance 5
Saves: Fort +5, Ref +7, Will +1
Abilities: Str 10, Dex 18, Con 12, Int 6, Wis 12, Cha 8

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Superhero (Ex): Hero Shrews take no Size Penalties to opposed Combat Checks.

Hm. No STR penalty and no size penalties in combat on a diminutive creature paired with that DR kind of hammers the point home, but given the crazy real life version, this could arguably use more weird stuff. I don't know, something like being considered two size categories larger when calculating encumbrance or immunity to damage from falling objects.

Time Flies

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Blowfly swarms

Those might not be the droids words you're looking for.

Hebecnema tempus

I'd go with temporalis (the adjective) or at least temporis (the genetive).