It is known from the Kanneliya-Dediyagala-Nakiyadeniya, Kitulgala, and Kottawa Forest Reserves and from the Sinharaja World Heritage Site.

[1][3] The specific name singu is Sinhalese for "horn" and refers to the horn-like tubercles on the upper eyelids of this frog.

There are scattered tubercles in the head, back, and the flanks; skin on the throat, chest, belly, and ventral sides of thighs is granular.

[2] Pseudophilautus singu occurs in lowland and mid-elevation rainforests at 60–513 m (197–1,683 ft) above sea level.

Forest reserves are at risk from encroachment by tea growers, and the associated use of biocides and fertilizers represent an additional threat to this species.