Dendronotus dalli Bergh, 1879

Common name(s): Dall's frond-aeolis

Synonyms: Dendronotus elegans Dendronotus dalli
Phylum Mollusca 
Class Gastropoda 
Subclass Heterobranchia (Opisthobranchia invalid)
Heteroclass Euthyneura
Subterclass Ringipleura 
Superorder Nudipleura 
Suborder Cladobranchia 
Superfamily Dendronotoidea 
          (Suborder Dendronotacea invalid)
Family Dendronotidae 
A small Dendronotus dalli, 3 cm long, found at 50 foot depth near Coffin Rocks, WA
(Photo by:  Dave Cowles, July 2020)

Description:  Dendronotids are Nudibranchs with the anus on the right side of the body and with 4-10 dorsal  cerata which are club-shaped, paddlelike or bushy; sometimes no cerata but numerous gills. Either way, they are arranged in 2 dorsolateral rows. The clavus of the rhinophore can be partly or fully retracted into its sheath. Dendronotus dalli has a sluglike body with 6-7 pairs of bushy cerata in 2 dorsolateral rows and with white on the distal third; large, prominent bushy rhinophores with white tips and a sheath that is drawn out into 4-12 (usually 5) moderately branched papillae in a crownlike shape (the two the rhinophores may have different numbers of papillae). The rhinophore stalk has lateral papillae but no posterior bushy outgrowths. It has an oral veil with 4-5 pairs of short, moderately branched papillae but the veil is not wide and only slightly overhangs the mouth. It has 20 (30) or more small, fingerlike lip papillae. The foot has no red or white line around its margin and the dorsum does not have 4 parallel reddish-brown longitudinal lines. The body is translucent white or pink. Length usually 4-8 cm but may be up to 14 cm. 

How to Distinguish from Similar Species:  Dendronotus iris has bushy outgrowths on the posterior part of the rhinophore stalk. Several other Dendronotus species such as Dendronotus albus have white tips on the cerata, but these also have a dorsomedial white line extending at least from the posterior cerata to the tip of the tail.

Geographical Range:  Bering Sea to Puget Sound, WA

Depth Range:  Very low intertidal to subtidal.

Habitat:  Lives and feeds on stalked bryozoans and hydroids, especially Abietinaria.

Biology/Natural History:  This species feeds on hydroids and on stalked bryozoans (photo). It is a good swimmer. It lays large, coiled egg masses with white or cream-colored eggs in summer (photo). 



 

References:

Dichotomous Keys:
  Kozloff, 1987, 1996

General References:
  Behrens, 1991
  Behrens and Hermosillo, 2005
  Byersdorfer and Watson, 2010
  Lamb and Hanby, 2005
  O'Clair and O'Clair, 1998

Scientific Articles:
 

Web sites:


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

On Abietinaria
This species lives and feeds on hydroids such as this Abietinaria it was found on, and on stalked bryozoans. Photo by Dave Cowles, July 2020

Eggs
The species lays coils of white or cream-colored eggs.


Authors and Editors of Page:
Dave Cowles (2018):  Created original page
CSS coding for page developed by Jonathan Cowles

Salish Sea Invertebrates web site provided courtesy of Walla Walla University