The nematode galls measured 0.5–1 mm in diameter for all the localities. Most nematode galls were single and separated from each, but some were clustered together (Fig. 5a and c). The nematode galls on the grass stems were softer in texture than those situated on insect galls and were deep purple to blackish in colour, non-pedunculate but slightly elevated above the surface of the grass stems and leaf sheaths (Fig. 5a–c). Galls on dry, brown stems and leaves were dark brown and somewhat elevated, but never pedunculated (Fig. 5f). The nematodes inside them were still alive. Insect galls were found on grass from Langebaan and Blouberg only. The nematode galls situated on top of the insect galls were always clustered, brown to dark brown in colour, matching the colour of the insect galls (Fig. 5d). They were also harder and drier and some of these dried-up galls contained no nematodes but were filled with particles that looked like debris under the microscope. No nematode galls were found on the insect galls from Blouberg (Table 3).

Galls formed by a nematode, Anguina woodi, were found on the stems, leaves and leaf sheaths of dune grass, Ehrharta villosa var. villosa on Milnerton Beach, Blouberg Beach and Langebaan, Western Cape Province, South Africa. These galls were spongy in texture, deep purple to blackish in colour and non-pedunculate. They were found in clusters, but also as single entities.

Nematode galls sometimes situated on top of, or next to the insects’ galls, were always brown to dark brown in colour, and appeared harder and drier than those found on grass stems and leaves.