A new myrmecophytic species, Neonauclea viridiflora, is described from Eastern Samar, Philippines. It bears similarity to N. formicaria, but is easily distinguished by having obovate leaves, smaller flowering heads of 30–35 mm, persistent calyces that are glabrous inside the tube, calyx shafts that are connate at the bases for 0.8–2.5mmor sometimes entirely connate with the adjacent lobe, apical portions of the calyces that are bluntly turbinate but globose to clavate when dry, calyx summits that are bluntly conical but the apex is somewhat flattened when dry, and smaller and slender light green corollas. Comparative illustrations of the calyx lobes, a key to the Philippine myrmecophytic Neonauclea species, and a map for these species' distributions in the Philippines are provided in the study.