Pelvetiopsis californica
Hesperophycus californicus
Range and habitat 3
Pelvetiopsis californica (previously Hesperophycus californicus) ranges from Monterey Bay, CA (USA) to Punta Eugenia, Baja (MEX) including the Channel Islands. P. californica is spatially patchy in its distribution and is absent from large stretches along its range on the mainland in southern California. This rockweed is found in the high intertidal zone near Endocladia muricata and normally above the larger confamilial rockweed, Silvetia compressa.
Morphology and identification 3
P. californica is a medium sized (40 cm max length) rockweed that varies in color from olive green to brown or almost black when desiccated, but is easily identified by two rows of tufts of white hairs (cryptostomata) running down both sides of wide (5.5-8 mm) flat dichotomous branches. Cryptostomata can be worn down by wave action and may be more conspicuous seasonally. When reproductive, P. californica has spatulate shaped receptacles at the end of branches that become filled with air. Pelvetiopsis californica has wider blades and two rows of cryptostomata on both sizes of branches but can be confused with Silvetia compressa, Pelvetiopsis hybrida, and Pelvetiopsis limitata. Compared to P. californica, Silvetia compressa has narrower more rounded branches and adult individuals are much larger (100 cm max length). Meanwhile, Pelvetiopsis limitata and P. hybrida are smaller (20 cm max length) with narrower width (2.5-5 mm) branches. P. limitata has no cryptostomata and P. hybrida only has cryptostomata on one side of branches.
Ecology and genetics 3
Rockweeds are ecosystem engineers that modify their environment by providing shade and habitat for other species. Pelvetiopsis californica has been shown to withstand desiccation better than Silvetia compressa, the rockweed found in the mid and high zone that P. californica competes with for space. P. californica was recently moved from the genus Hesperophycus, where it was the sole member, to Pelvetiopsis based on genetic analyses. Additionally, Pelvetiopsis californica hybridized with the Monterey endemic rockweed, Pelvetiopsis arborescens to form Pelvetiopsis hybrida.
Sources and Credits
- (c) intertidalecologist, all rights reserved, uploaded by intertidalecologist
- (c) Laura Camp, some rights reserved (CC BY-SA), https://www.flickr.com/photos/24284031@N00/22769202415/
- (c) intertidalecologist, some rights reserved (CC BY-SA)
More Info
Range Map
iNat Map
| Common name | Algae, Brown Algae |
|---|---|
| Region | Channel Islands South, Government Point to Mexico, San Francisco to Government Point |
