Nelson (and ITIS and other sites that follow him) places this group of fishes as suborder Syngnathoidei of Gasterosteiformes. Nelson and Keivany (2006) found Gasterosteiformes (including Syngnathoidei) to be monophyletic, while Kawahara et al. (2008) found it not to be.
- Keivany, Y. and Nelson, J.S. 2006: Interrelationships of Gasterosteiformes (Actinopterygii, Percomorpha). Journal of Ichthyology 46 Supplement 1, S84-S96. doi: 10.1134/S0032945206100055
- Kawahara, R., M. Miya, K. Mabuchi, S. Lavoué, J.G. Inoue, T.P. Satoh, A. Kawaguchi, and M. Nishida 2008: Interrelationships of the 11 gasterosteiform families (sticklebacks, pipefishes, and their relatives): A new perspective based on whole mitogenome sequences from 75 higher teleosts. Molecular Phylogenetics and Evolution 46 Issue 1, Pages 224-236. doi: 10.1016/j.ympev.2007.07.009