...the body length of a natterjack toad is 4.5-5.5 cm. It is characterised by warty, dry skin. On the sides of the head, there are small parotoid poison glands, which are dark red or brown in colour. The back is yellowish-grey or greenish-brown with more or less dark speckling. A narrow, yellowish stripe characteristic of the species runs down the back. The underside is light with small, dark spots. The pupils are horizontal. The male is smaller; during the spawning season, it differs from the female by having dark brown nuptial pads on the inner side of the forelimbs and a dark throat. The internal vocal sac is well-developed; it sings quite intensely throughout the spawning period; the song is very specific, resembling the loud chirping of a cricket, which can be heard for kilometres on quiet summer nights..