Like a weapon shield the lesser boatsman's head is placed in front of the body, which enables it to storm through the underwater world without much difficulty. Placed in an aquarium it seems that the insect at periods tries to burst through the glass with it's head. In a side view it looks like a strange alien mask. (see the picture at the right, can be enlarged by clicking). The single chitin plates which build the head can not be found because of their seamless "welding", on the left picture you can see a reverted-U shaped groove running at the front side, marked at the lower end by little brown lines. (Please click on the picture to see more detail) The head is connected without distinctive marking to the ribbed snout, which ends in a small mouth opening. The ribs are used by the male to create the chirping sound. The snout or proboscis is stiff and broad, very different from the normal agile and needle shaped one most bugs have. The lesser boatsman doesn't need it: it's mouth is more a sort of vacuum cleaner, with which it sucks up the food particles collected by the front legs. But some of them are capable of stabbing their food, for example algae, water plants or insect-eggs.
The scull of many lesser water boatman is pointed on the top as you see on the left. SOme of them have a deep groove between the eyes, others have a haired face. These characteristics are used in determination of the species.
The eyes are relatively large and are composed of hundreds of facets. They are colored red during the first days after a moult, after that they gradually darken to a brown colour.