Diadumene lineata (Verrill, 1871) Common name(s): Orange-striped green anemone, lined anemone, Japanese anemone
Synonyms: Haliplanella lineata, Haliplanella luciae, Diadumene luceae, Aiptasiomorpha luciae
Phylum Cnidaria Class Anthozoa Subclass Zoantharia (Hexacorallia) Order Actiniaria Family Haliplanellidae
	Diadumene lineata, 0.8 cm diameter, attached to a pebble from the muddy east side of Padilla Bay
	(Photo by: Dave Cowles, June 2022 )

Description:  Like most (but not all) anemones this small but colorful anemone has a flat pedal disk and adheres to solid objects such as rocks, wood, and shells. It has acontia which it can extrude from the column walls for defense when damaged or disturbed. The column is green (occasionally brownish) with 7-19 orange or yellow (sometimes white) vertical stripes. It has more than 24 but less than 100 tentacles. Height up to 2 (3) cm and 1 cm diameter (up to 4 cm at the base where the pedal disk may spread out). 

How to Distinguish from Similar Species:  Few other anemones have acontia, and the others in the Salish Sea that do (Metridium spp) are generally orders of magnitude larger than this species and have many more, fine tentacles. Unfortunately, anemones don't always extrude their acontia when disturbed so this is not a completely reliable characteristic. It does not have tubercles on the column wall so when closed it can be confused with small Epiactis species The vertical orange stripes on the column wall are broader than those found in some Epiactis and are quite distinctive.  It also does not appear to have colored bands on the oral disk as most Epiactis do although I could be wrong on this.. D. franciscana from San Francisco bay is very similar but the tentacles opposite the corners of the mouth have yellow bases and the column has white stripes.

Geographical Range:  Very broadly distributed. Alaska to southern California on our coast.

Depth Range:  Intertidal or shallow subtidal

Habitat:  Lives in the high intertidal zone in quiet bays and estuaries, often inside shell fragments or empty barnacle tests, cracks in rock or wood, often near mud, or on floats and pilings..

Biology/Natural History:  This small anemone is easily (and accidentally) transported by humans and is the most widely distributed anemone species in the world. It probably originated in northeast Asia. It is thought to have been introduced into the Salish Sea along with oysters imported from Japan. This species may be found in aggregations, especially in crevices, due to asexual reproduction (accomplished by binary fission similar to that of Anthopleura elegantissima). This species is fed on by nudibranchs such as Cuthona perca and Hermissenda crassicornis.

References:

General References:
  Harbo, 2011
  Kozloff, 1993 (as Haliplanella lineata)
  Lamb and Hanby, 2005
  Ricketts and Calvin, 1985 (As Haliplanella luciae)

Scientific Articles:
 

Web sites:

General Notes and Observations: Locations, abundances, unusual behaviors:
 
Diadumene lineata is quite common in some of the muddier portions of Padilla Bay. This photo shows an aggregation of Diadumene lineata and Batillaria attramentaria clustered on the broken, intertidal top of a piling that is elevated just above the mud at low tide in eastern Padilla Bay along the shoreline just south of Samish Island. Photo by Dave Cowles August 2022

Authors and Editors of Page:
Dave Cowles (2022):  Created original page
CSS coding for page developed by Jonathan Cowles

Salish Sea Invertebrates web site provided courtesy of Walla Walla University