The Philanthus does not paralyse merely, but kills.
This is one step gained.

The murderer chooses the point below the chin as the point of attack, in order to reach the principal centres of innervation, the cephalic ganglions, and thus to abolish life at a single blow.

The vital centres being poisoned, immediate death must follow.

If the object of the Philanthus were merely to cause paralysis she would plunge her sting into the defective corselet, as does the Cerceris in attacking the weevil, whose armour is quite unlike the bee's.

Her aim is to kill outright, as we shall presently see; she wants a corpse, not a paralytic.