It is a martelo that starts from the ground. The Martelo no Chão is delivered from a lower position usually right before a rolé while in esquiva baixa or downward going into a queda de rins.
Starting from the negativa position, bring your weight forward and pull your hips up off of the floor. Once your hips are up I the leg that you were sitting on will come around like a roundhouse kick to strike at either the legs, stomach, or head of your target. This kick can be very difficult to do because it does come from a very awkward position. For this reason a requires a lot of practice and comfort with moving on the floor. It’s also very important to practice some of the more fundamental movements that were mentioned (ie. Rolê, , and Martelo). The kick finishes in the base position of the Ginga where you can transition into any other movement.