Yes, the Phalanx is from Macross - it's probably the most obscure Human-side mecha from the original show. As I mentioned above, it shares the lower torso and legs of the Defender and Tomahawk.
All three were commonly used as either mobile turret emplacements on the outer hull or gathered in the fore part of the Daedalus carrier as part of the "Daedalus Maneuver" where the Macross would literally punch the carrier into the hull of a Zentraedi ship and then the massed mecha would unload their payloads as the main door of the carrier opened up inside the enemy craft.
All three were commonly used as either mobile turret emplacements on the outer hull or gathered in the fore part of the Daedalus carrier as part of the "Daedalus Maneuver" where the Macross would literally punch the carrier into the hull of a Zentraedi ship and then the massed mecha would unload their payloads as the main door of the carrier opened up inside the enemy craft.