Morphological variation between Lion's Mane jellyfishes from Australian coastal waters

Rob Condon
University of Maryland

Wednesday, October 6, 1999
3:00 p.m.—Pacific Forum

The proper taxonomic classification of Lion’s Mane jellyfishes, genus Cyanea (Scyphozoa; Semaeostomeae), over the past century and a half has been problematic. Poor taxonomy, lack of data, and differing approaches amongst cnidarian researchers has resulted in considerable confusion regarding the classification of Cyanea. Such confusion currently exists for Cyanea jellyfish distributed in Australian coastal waters. For example, medusae from temperate Australian waters morphologically resemble a cold water species, C. lamarcki. However, like many other worldwide members of this genus, this scyphomedusan is grouped under the "cosmopolitan" species, C. capillata.

In order to resolve this conflict, I examined in detail the external morphology of specimens housed in the major Australian museums and medusae collected from the field in Northern and Southeast Australian waters. Additional information on nematocyst abundance and ultrastructure within and across life cycle stages was collected and explored as a possible alternative in the determination of Cyanea species. The results of this study will be presented in this seminar as well as comments on the use of the nematocyst in the delineation of scyphozoan species.

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