Species
Didymograptus primigenius Bulman, 1950
Classification
| Organism group | Biota |
| Kingdom | Animalia |
| Phylum | Hemichordata |
| Class | Pterobranchia |
| Subclass | Graptolithina |
| Order | Graptoloidea |
| Suborder | Dichograptina |
| Family | Didymograptidae |
| Genus | Didymograptus |
| Species | acutus |
| artus | |
| broggeri | |
| cinereus | |
| decens | |
| ensjoensis | |
| extensus | |
| flexilis | |
| geminus | |
| goldschmidti | |
| grandis | |
| holtedahli | |
| kreklingensis | |
| leptograptoides | |
| murchisoni | |
| opimus | |
| oscillatoris | |
| pakrianus | |
| primigenius | |
| propinquus | |
| protoindentus | |
| serpens | |
| slemmestadi | |
| stensbergensis | |
| vicinatus |