Question

in the blanks
The tubelike
like mouthpart of a butterfly is called a​

Answer 1

Proboscis  is the tubelike  mouthpart of a butterfly.

Explanation:

During rest, the tube-like structure which acts as the mouth part of the butterfly called the proboscis stays attached firmly against the head.  When the butterfly moves to encourage upon the nectar of a blossom or something associated, the proboscis spreads out to expand descending into the middle of the flower.

The uncoiling is started in the muscle nearest to the head, the basal galeal muscle, which lifts the loops somewhat to "open" it from its firmly held position.