(of)Keferstein, W. (1866). Untersuchungen uber einige amerikanische Sipunculiden. <em>Nachrichten von der Königlichen Gesellschaft der Wissenschaften und der Georg-August-Universität zu Göttingen.</em> 14: 215-228.[details]
Saiz, J. (2021). World Sipuncula Database. Phascolosoma (Phascolosoma) agassizii Keferstein, 1866. Accessed through: Xu, K., An, J., Ding, L., Dong, D., Gao, Y., Huang, Y., Jiang, W., Lei, Y., Li, K., Li, X., Li, Y., Liang, X., Lin, G., Lin, M., Liu, H., Liu, J., Liu, W., Liu, X., Lu, D., Ma, Z., Ren, X., Sha, Z., Sun, J., Sun, S., Sun, Z., Tian, L., Wang, D., Wang, J., Wu, X., Xia, B., Xiao, N., Yin, J., Zhang, J., Zhang, S., Zhang, X., Zhao, E., Zheng, X., Zhou, H., Zhou, J. & Zhou, K. (2021) Chinese Register of Marine Species at: https://marinespecies.org/charms/aphia.php?p=taxdetails&id=266496 on 2026-07-13
Xu, K., An, J., Ding, L., Dong, D., Gao, Y., Huang, Y., Jiang, W., Lei, Y., Li, K., Li, X., Li, Y., Liang, X., Lin, G., Lin, M., Liu, H., Liu, J., Liu, W., Liu, X., Lu, D., Ma, Z., Ren, X., Sha, Z., Sun, J., Sun, S., Sun, Z., Tian, L., Wang, D., Wang, J., Wu, X., Xia, B., Xiao, N., Yin, J., Zhang, J., Zhang, S., Zhang, X., Zhao, E., Zheng, X., Zhou, H., Zhou, J. & Zhou, K. (2026). Chinese Register of Marine Species. Phascolosoma (Phascolosoma) agassizii Keferstein, 1866. Accessed at: https://marinespecies.org/charms/aphia.php?p=taxdetails&id=266496 on 2026-07-13
original description(of)Keferstein, W. (1866). Untersuchungen uber einige amerikanische Sipunculiden. <em>Nachrichten von der Königlichen Gesellschaft der Wissenschaften und der Georg-August-Universität zu Göttingen.</em> 14: 215-228.[details]
additional sourceCutler, E.B. (2009). Phylum Sipuncula: peanut worms, in: Gordon, D.P. (Ed.) (2009). New Zealand inventory of biodiversity: 1. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. pp. 302-307.[details]
source of synonymyCutler, Norma J.; Cutler, Edward B. (1990). A revision of the subgenus Phascolosoma (Sipuncula: Phascolosoma). <em>Proceedings of the Biological Society of Washington.</em> 103(3) : 691-730., available online athttps://www.biodiversitylibrary.org/page/34592151[details] Available for editors
source of synonymyFisher, W. K. (1952). The Sipunculid Worms of California and Baja California. <em>Proceedings of the United States National Museum.</em> 102(3306): 371-450. plates 18-39., available online athttps://doi.org/10.5479/si.00963801.102-3306.371[details]
Present Inaccurate Introduced: alien Containing type locality