Olenidae
| Olenidae | |
|---|---|
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | †Trilobita |
| Order: | †Ptychopariida |
| Suborder: | †Olenina |
| Superfamily: | †Olenoidea |
| Family: | †Olenidae Burmeister, 1843 |
| genera | |
|
see text | |
Olenidae is a family of ptychopariid trilobites. Some genera, Balnibarbi and Cloacaspis, are thought to have evolved a symbiotic relationship with sulfur-eating bacteria from which they derived nutrition.