Marpissa pikei has a very elongated form, which enables it to hide while stretching along twigs or blades of grass.

While the male has a broad black median stripe spanning the whole body and orange first legs and carapace orange, the female has a duller coloration, with the abdomen pale cream-colored, speckled with black.

When males spot a female, they approach it with their front legs extended and waving, prior to mating.

Kaston (1981) reports it as readily swept from tall grasses, especially along seashores.

This species is commonly called Pike Slender Jumper or Long-bodied Jumping Spider.