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Name derivation:

Palmaria= L. palma: palm of the hand or shaped like a hand

palmata=  L. palma: palm of the hand or with branches radiating from a central area

Common names: dulse and dillisk

Dulse is a good snack food after being dried and with little other preparation

Classification:

Palmaria  Stackhouse  1802;  10 of 19 species descriptions are currently accepted taxonomically (Guiry and Guiry 2014).

Order Palmariales;  Family Palmariaceae

 

Morphology:

Algae composed of multiple purple-reddish foliose fronds that are attached to a discoid holdfast. Fronds are highly variable, being strap-shaped, simple, dichotomously, or palmately divided and often having multiple marginal proliferations. Life histories are heteromorphic.  Male and tetrasporangial algae are large foliaceous fronds, with blades having 1-2 layers of large, spherical medullary cells and a cortex of pigmented small cells.  Tetrasporangia are cruciate and form dark sori  on the outer frond surface.  Male algae have surficial spermatangia , occurring in continuous irregular sori and appearing as yellowish patches. Female algae are minute cushions with embedded carpogonia. Tetrasporangial and spermatangial algae are common throughout the year. The algae is either a perennial or aseasonal annual.

Similar genera:

Superficially looks like the introduced Asiatic taxon Grateloupia turuturu, but it lacks spherical medullary cells, has conspicuous filamentous medullary cells,  and has a slimy surface texture.

Habitat:

Present year-round, growing on large algae (e.g. kelp stipes), on intertidal rocks and pilings, in tide pools and to 20 m.

 

 

References:

Bird, C. J., and McLachlan  1992.  Seaweed flora of the maritimes 1. Rhodophyta – the red algae. Biopress Ltd., Bristol, England, v + 177 pp.

Guiry, M.D. and G.M. Guiry  2014.  AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 19 December 2012.

Taylor, W. R.  1957.  Marine Algae of the Northeastern Coast of North America. Revised edition. Univ. Michigan Press., Ann Arbor, ix + 509 pp. (as Rhodymenia palmata)