Solmissus marshalli A. agassiz and Mayer, 1902. Common name(s): Dinner plate medusa
Synonyms:
Phylum Cnidaria  Class Hydrozoa  Subclass Trachylina  Order Narcomedusae  Family Cuninidae
	Solmissus marshalli, about 3.5 cm diameter, dorsal view. The gray blotches in the stomach pouches under the tentacles and lappets are apparently statocysts.
	(Photo by:  Dave Cowles, June 2025. Collected by Jamie Fields from Sharpe Cove dock at night)

Description:  This species has a bell which is fairly thick in the center but has thinner side walls. It is much wider than tall, which leads to the "dinner plate" name. Unlike most hydromedusae, it has no extensive manubrium at its mouth-instead the mouth is a simple hole in the middle of the subumbrella. Instead of having radial canals, the stomach is large, extends nearly out to the tentacles, and ends with a series of oval or squared-off pouches that extend under each tentacle (photo above). Up to several gray stomatocysts may be in the area of each pocket (photo above). The ring of 8-40(usually 16)  tentacles is spaced out evenly and  based well up the outer surface of the bell (exumbrella). They extend upward near the base but when extended curve downward at the distal end. The species has marginal lappets near the tentacles, each of which has up to 20 sensory clubs, but has no otoporpae (bristled tracts running up the external margin of the bell). The bell diameter is up to 6 cm, and usually transparent with no color, but may have some pink or blue coloration. 

How to Distinguish from Similar Species:Solmissus  incisa is less common, can be larger (up to 10 cm diameter), is found more commonly offshore, and has fewer sensory clubs (2-5 per pocket). Cumina sp. has octoporpae.

Geographical Range:  Worldwide in tropical and temperate oceans.

Depth Range:  From the surface down to abyssalpelagic depths (at least 4000 meters)

Habitat:  Pelagic

Biology/Natural History:  Members of Order Narcomedusae lack polyps in their life cycle. Diet includes other medusae, ctenophores, and salps.

References:

General References:
  Wrobel and Mills, 1998 

Scientific Articles:
Robison, B. and J. Connor, 1999. The deep sea. Monterey Bay Aquarium Press, Monterey, CA

Web sites:

General Notes and Observations: Locations, abundances, unusual behaviors:

This oblique view clearly shows the partly-retracted tentacles attached to the exumbrella well above the margin of the bell.

Authors and Editors of Page:
Dave Cowles (2025):  Created original page
CSS coding for page developed by Jonathan Cowles

Salish Sea Invertebrates web site provided courtesy of Walla Walla University