Spider's calf

Pitfall

named for the video game; the marks on the right fluke look like someone swinging on a vine

Tenedor's calf

Chinook

the black mark on the right fluke reminds one of a salmon swimming upstream

Tongs's calf

Mousetrap

the black marks on the right fluke appear to be a basket ready to drop down on the trap, as in the kid's game

Ursa's calf

Mobila

the reverse image on the left fluke resembles a manta ray swimming at you (with two eyes high on its head)

Warrior's calf

Paintball

splats of dark color remind one of the effects of a paintball attack

Non-calves

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Calves

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