Neoturris brevicornis (Murbach and Shearer, 1902)

Common name(s): 
Synonyms: Neoturris brevicornis
Phylum Cnidaria 
Order Hydroida 
Suborder Athecata (Anthomedusae) 
Family Pandeidae 
 
Neoturris brevicornis, about 2 cm diameter, Collected from Rosario Strait
(Photo by:  Dave Cowles, August 2010)
Description:  This hydroid medusa has numerous (usually >100) unbranched tentacles originating at the margin of the bell and evenly distributed around the bell margin.  The bell is not opaque.  The tentacle bases usually have an orange tinge but have no ocelli.  The tentacles have no prominent rings of nematocysts.  The four broad radial canals have jagged edges but do not branch nor do they have prominent lateral diverticula.  The gonads are associated with the stomach, not with the radial canals.  The height of the bell is greater than or equal to its diameter and the jelly is thick at the apex of the bell.  The manubrium usually has an orange tinge (this one doesn't appear to (photo)).  Bell height to 5.3 cm.

How to Distinguish from Similar Species: Catablema multicirrata has a similar shape and many tentacles but the apex of the bell usually has a large, bulbous projection and it doesn't have orange on it.

Geographical Range: North Pacific (Bering Sea to Monterey Bay), Arctic, and North Atlantic oceans.

Depth Range:

Habitat:  Pelagic

Biology/Natural History:  The polyp stage is unknown for this species.  Very little seems to be known about its biology. 

.The normal life cycle of hydrozoans is for male and female medusae to release sperm and eggs. After fertilization, the fertilized egg divides and becomes a small, ciliated planula larva. The planula settles to a surface and grows into a branched colony of attached polyps. Medusae bud from some of the polyps in the colony to complete the life cycle. Another athecate hydrozoan, Turritopsis dohrnii, however, which is widespread in warm oceans, has recently been discovered to have an unusual skill. If the sexually mature medusae are injured or encounter unfavorable conditions such as warmth, modified salinity, or pinching, the mature, differentiated cells of the medusa can de-specialize and form into a cyst, which is a ball of pluropotent stem cells. The cyst settles to the bottom and grows back into a new polyp colony. This behavior thus allows them to take a shortcut backwards to an earlier stage in their life cycle. Currently this is the only known sexually mature, multicellular animal that can do this. Not even Turritopsis rubra, a member of the same genus, appears to be able to do this. Some of the main scientists who discovered this phenomenon include Maria Pia Miglietta, Maria Pascual-Turner, and Stefano Piraino. A summary of their research and a list of several key references can be found here in the journal "The Scientist". Whether other athecate  hydroids such as Neoturris can do this is not known.


 
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References:

Dichotomous Keys:
  Carlton, 2007
  Kozloff, 1987, 1996

General References:
  Wrobel and Mills, 1998

Scientific Articles:

Web sites:

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


Manubrium

The manubrium can be seen in this closeup.


Authors and Editors of Page:
Dave Cowles (2010):  Created original page
CSS coding for page developed by Jonathan Cowles (2007)

Rosario Invertebrates web site provided courtesy of Walla Walla University