Abstract: A tube valve, an actuator mechanism for a tube valve, a jaw for a tube valve, and a tube valve assembly including all of them. In one embodiment the tube valve has a valve body and a jaw movably mounted thereon, the jaw suitable for holding hollow flexible tubing and moving it into operative contact with a valving member for providing valving action of closing-off and opening-up the tubing to the flow of fluid therethrough. The valving member may be movably disposed through the valve body so that it can be moved into and out of operative contact with the tubing while the jaw is in position about the plunger. A latch assembly may be provided for holding the jaw in position about the plunger. In one embodiment the latch assembly includes a neck and a shaft attached thereto, the neck pivotably mounted to the valve body so that it can be pivoted to move the shaft into a holding recess in the jaw. The actuator mechanism has a lever member pivotably mounted to a housing.