[2][3][4] Common name Holt's robber frog has been coined for this species.

The dorsum is smooth to granular, with small granulations on the sides.

The dorsal coloration is variable: uniformly dark brown or gray, exhibiting green or irregularly distributed red spots, sometimes with two dark longitudinal bands running from the eyes to the posterior region, or light green with brown spots.

[3] Ischnocnema holti inhabits forests, ravines, and high-altitude grasslands.

Its altitudinal range in Itatiaia is 2,000–2,400 m (6,600–7,900 ft) above sea level, although a male was heard calling at 1670 m in Garganta do Registro [pt].