Trapezius 1
I would imagine that would be the trapezius muscles.
Upper fibres of the trapezius, rhomboid minor and major and levator scapulae.
The serratus anterior is one, and the lower trapezius muscles are the others. The SA muscles pull the scapulae downward and anteriorly while the lower traps pull downward and medially.
Levator scapulae
Levator scapulae.
Levator scapulae and trapezius
The muscles involved in elevating the shoulder girdle (e.g. shrugging your shoulders) are the upper fibers of trapezius, levator scapulae, rhomboid major and rhomboid minor.
elevates, adducts, depresses, or rotates the scapula
a combined contraction of the levator scapulae, rhomboid major and minor muscles and the latissimus dorsi muscle.I would narrow this answer down to the Rhomboid Muscles-Luceinrhomboids
Trapezius and Levator Scapulae
levator scapulae
serratus anterior