Journal of the Marine Biological Association of the United Kingdom

Research Article

A re-examination of siphonophore terminology and morphology, applied to the description of two new prayine species with remarkable bio-optical properties

Steven H.D.  Haddock a1c1, Casey W.  Dunn a2 and Philip R.  Pugh a3
a1 Monterey Bay Aquarium Research Institute, 7700 Sandholdt Rd, Moss Landing, California, 95039, USA
a2 Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, 06520 USA
a3 National Oceanography Centre, Southampton, SO14 3ZH, UK

Article author query
haddock sh   [PubMed][Google Scholar] 
dunn cw   [PubMed][Google Scholar] 
pugh pr   [PubMed][Google Scholar] 


Siphonophores (Cnidaria: Hydrozoa) are dominant members of the carnivorous plankton, and they are known for their ability to produce bioluminescence. Here we describe two new calycophoran species (sub-family Prayinae) that are unique in their morphological and optical traits. One species, Gymnopraia lapislazula gen. nov., sp. nov., displays a dramatic form of blue structural coloration, and the other, Lilyopsis fluoracantha, sp. nov., bears an exceptional amount of fluorescence–enough to give a greenish cast during white-light illumination. We also introduce a consistent terminology for siphonophore axes and zooids, discuss characters important for distinguishing the known prayine genera, and suggest that the presence or absence of a disjunct pedicular canal could be of diagnostic value for the group.

(Received February 19 2005)
(Accepted March 27 2005)

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