Urinant positioned vertically with heads sinking downwards -a rare posture. Naiant swimming fesswise -a common posture. Embowed applies to any fish that has its body arched as if it were leaping. Think of hauriant with the fish curved in an arc with the bend to the right. Less common than passant.
Sejant beast is seated with forelegs down and together.
Tail is up by default if the beast has a tail . A common posture for carnivorous beasts and monsters. A common posture for non-carnivorous beasts. If the beast has a tail it is down and coiled around the animal. Very rare in period.