<==o Pycnogonida Latreille, 1810 (sea spiders; merilukit)
|?-o †Nectopantopoda
| `--o †Haliestidae
| `-- †Haliestes dasos Siveter, Suton, Briggs & Siveter, 2004
|?-o †Palaeoisopoda
| `--o †Palaeoisopodidae
| `-- †Palaeoisopodus problematicus Broili, 1928
|?-o †Palaeopantopoda
| `--o †Palaeopantopodidae
| `-- †Palaeopantopus maucheri Broili, 1929
`--o Pantopoda
|--o Stiripasterida
| `-- Austrodecidae Stock, 1954
`--o Eupantopodida
|-- Endeis [Endeidae]
|--o Ascorhynchoidea
| |-- Ammotheidae Dohrn, 1881 [Acheliidae; Ammothellidae; Tanystylidae]
| `-- Ascorhynchidae Hoek, 1881 [Eurycydidae Sars, 1891]
|--o Colossendeidoidea
| `-- Colossendeidae Hoek, 1881 [Rhopalorhynchidae]
|--o Nymphonoidea
| |-- Callipallenidae
| |-- Nymphonidae
| `-- Pallenopsidae
|--o Phoxichilidoidea
| `--o Phoxicilidiidae [Anoplodactylidae]
| |-- Anoplodactylus
| |-- Phoxichilidium
| |-- Phoxiphilyra
| |-- Pycnosomia
| |?- Halosoma
| `?- Philyra
|--o Pycnogonoidea
| `--o Pycnogonidae
| |-- Clotenopsa
| |-- Pentapycnon
| `-- Pycnogonum
`--o Rhynchothoracoidea
`--o Rhynchothoracidae
`-- Rhynchothorax
Reference(s):