Spengel, J.W. (1893). Die Enteropneusten des Golfes von Neapel. in: Fauna und Flora des Golfes von Neapel und der angrenzenden Meeres-Abschnitte. Herausgegeben von der Zoologischen Station zu Neapel, Berlin. pp. 756., available online athttps://doi.org/10.5962/bhl.title.11517 page(s): 359 [details]
Swalla, B.J.; van der Land, J. (2025). Hemichordata World Database. Ptychoderidae Spengel, 1893. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=2019 on 2025-04-15
original descriptionSpengel, J.W. (1893). Die Enteropneusten des Golfes von Neapel. in: Fauna und Flora des Golfes von Neapel und der angrenzenden Meeres-Abschnitte. Herausgegeben von der Zoologischen Station zu Neapel, Berlin. pp. 756., available online athttps://doi.org/10.5962/bhl.title.11517 page(s): 359 [details]
basis of recordvan der Land, J. (2001). Hemichordata, in: Costello, M.J. et al. (Ed.) (2001). European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels, 50: pp. 336 (look up in IMIS) [details]
Other
additional sourceHayward, P.J. & J.S. Ryland (Eds.). (1990). The marine fauna of the British Isles and North-West Europe: 1. Introduction and protozoans to arthropods. Clarendon Press: Oxford, UK. 627 pp. (look up in IMIS) [details] Available for editors [request]
Present 