Pajama Cardinalfish (Sphaeramia nematoptera)

The Pajama Cardinalfish looks like it got dressed by committee — a yellow-striped face, a copper saddle, and a rear half covered in dark polka dots that don't match anything else on its body. Those oversized eyes are built for naturally nocturnal feeding habits, and like every cardinalfish it's a mouthbrooder, with males fasting for about a week while carrying a clutch of eggs.

Care level: Easy · Temperament: Peaceful, shoaling · Max size: ~3" · Min tank: 30 gal · Diet: Carnivore, meaty foods