Pleurophycus gardneri is a species of brown alga. It is a deciduous kelp, primarily found in lower, rocky inter-tidal and shallow, rocky sub-tidal locations[1][2] and is one of the most abundant kelps found within the Pleurophycus Zone (roughly 30-45m depth).[3] It is not commonly present deeper in the ocean than 30m and is considered a stipitate kelp.[3] P. gardneri forms aggregates of densities up to 10m−2 . These kelp beds reside below giant kelp forests, and were therefore often overlooked by researchers for many years.[3] This kelp has a range from Central California to British Columbia, Canada, with a lifespan of only 3 – 6 years.[2]
| Pleurophycus gardneri | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Clade: | Diaphoretickes |
| Clade: | SAR |
| Clade: | Stramenopiles |
| Phylum: | Gyrista |
| Subphylum: | Ochrophytina |
| Class: | Phaeophyceae |
| Order: | Laminariales |
| Family: | Alariaceae |
| Genus: | Pleurophycus |
| Species: | P. gardneri
|
| Binomial name | |
| Pleurophycus gardneri Setchell & Saunders ex Tilden
| |
The family of P. gardneri was previously believed to be Laminariaceae and not Alariaceae, but molecular data supports this particular kelp to be of the family Alariaceae.[4] P. gardneri has been referred to as Tender Kelp (1980) or Sea spatula (1985).[5]
Interactions with other species
editPleurophycus gardneri is a habitat to many species of amphipod, and most commonly supports species specific to stipe burrowing.[2] Amphipods decrease the lifespan of this kelp due to damages caused by burrowing; any breaks in the plants' holdfast up to its stipe will kill the plant, hence its heightened mortality rate due to stipe burrowing amphipods. Breaks above the abscission zone of the plants' frond will not kill the plant, but may still decrease fitness.[2]
Reproduction
editPleurophycus gardneri reproduces in the same way as all other kelp. It has diploid sporophytes and a microscopic haploid gametophyte stage.[2] Mature algal blades have a thick mid-rib which contain sori for reproduction.[3] A sorus is able to produce gametes for the kelp.
Perennial characteristics
editMature algal blades have a length of roughly 150 cm.[3] Annual banding can be found in the stipe of the plant due to its deciduous nature, which researchers often use to identify plant age.[2] P. gardneri loses all foliage by late fall and then soon thereafter (after a roughly two-week dormancy) begins to grow new blades.[6] For new blades to begin growing, light must be present. [6][3] Premature blade deterioration and breakages were seen as a direct result of warmed ocean temperatures. It is believed that temperatures around 14-15 C trigger blade deterioration. Following an El Niño, this kelp was recorded to have prematurely dropped blades.[6]
References
edit- ^ Erickson, Richard A.; Burt, Weston G. (2019-04-17). "Additional Information on a Nonnative Whiptail Population (Aspidoscelis flagellicauda/sonorae complex) in Suburban Orange County, California". Bulletin, Southern California Academy of Sciences. 118 (1): 76. doi:10.3160/0038-3872-118.1.76. ISSN 0038-3872. S2CID 146050615.
- ^ a b c d e f Pfister, Catherine A.; Betcher, Samuel P. (26 October 2017). Wernberg, T. (ed.). "Climate drivers and animal host use determine kelp performance over decadal scales in the kelp Pleurophycus gardneri (Laminariales, Phaeophyceae)". Journal of Phycology. 54 (1): 1–11. doi:10.1111/jpy.12601. PMID 29072316.
- ^ a b c d e f Spalding, Heather; Foster, Michael S.; Heine, John N. (28 March 2003). "COMPOSITION, DISTRIBUTION, AND ABUNDANCE OF DEEP-WATER (>30 m) MACROALGAE IN CENTRAL CALIFORNIA". Journal of Phycology. 39 (2): 273–284. doi:10.1046/j.1529-8817.2003.02010.x. S2CID 85144311.
- ^ Silva, Paul C. (2009-04-14). "Historical, Nomenclatural, and Distributional Notes on Two Pacific Coast Kelps: Lessoniopsis littoralis and Pleurophycus gardneri (Phaeophyceae, laminariales, alariaceae)". Madroño. 56 (2): 112–117. doi:10.3120/0024-9637-56.2.112. ISSN 0024-9637. S2CID 86302490.
- ^ "Pleurophycus gardneri Setchell & Saunders ex Tilden 1900 :: Algaebase". www.algaebase.org. Retrieved 2020-04-12.
- ^ a b c Germann, Iddamaria (1986-11-01). "Growth phenology of Pleurophycus gardneri (Phaeophyceae, Laminariales), a deciduous kelp of the northeast Pacific". Canadian Journal of Botany. 64 (11): 2538–2547. doi:10.1139/b86-336. ISSN 0008-4026.