|Haliscera conica Vanhoffen, 1902, top; H. bigelowi Kramp, 1947, bottom
Phylum Cnidaria / Class Hydrozoa / Order Trachymedusae / Family Halicreatidae
Both of these deep-water species are commonly collected in mid-water trawls. They are characterized by a bell width no more than 2.5 cm, and a rounded to conical apical projection (more pronounced in Haliscera conica). The mouth and stomach are circular, and connect to 8 broad radial canals. The canals are typically swollen in their midsection by flat. oval gonads. The velum is quite broad. About 160 tentacles (lost in these trawl collected specimens) line the bell margin. They have nematocysts concentrated in the distal (farthest) ends, and are about 1 to 3 times as long as the bell width. Both species are transparent and colorless, but may have an orange tinge to the canals and gonads, or rose-pink stomach and mouth (as seen in the photo of Haliscera bigelowi). They inhabit mid-water zones in both the Atlantic and Pacific Oceans.
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