Invasive SpeciesHeterosiphonia

Dasysiphonia japonica
FOUND by jmiller33
ID Questioned
Quality checked by Jeremy Miller
Peer reviewed by
Field Notes
On about Christmas day, my next door neighbor, Gary Sredzienski - known as "The Creekman" - reported seeing considerable amounts of an orange-red plant over a wide area in Spruce Creek. He swims in Spruce Creek (and other spots in the region) at least 300 days per year. He reported never seeing this phenomenon before. I got him to bring in a specimen, which he did, and which appears to be Heterosiphonia japonica: heavily corticated main branches, 4-pericentral cells forming secondary branches, single-cell ultimate branches with no "lobster-claw" tips. It appears to match on-line photos of the species (and not other local Rhodomelaceae).
Supporting Evidence
Photo of my evidence.
microscope photos taken at Wells NERR. Sample may have been bleached by sun/preservative.
Photo of my evidence.
attempt at close up. Sample may have been bleached by sun/preservative
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Common name:
Scientific name:
Dasysiphonia japonica
Sampling method: 
Just looking around
Photo of our sampling method.
Place Studied
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Map this species
N 43.092427 °
W -70.720410 °
Observation Site Information
A photo of our study site.
Coastal - Mudflat
Trip Information
Spruce Creek, Kittery, ME
Trip date: 
Fri, 2017-01-06 09:22
Town or city: 
Type of investigation: 
Species Survey
Time of low tide: 
Fri, 2017-01-06 10:54


What about the cells? Did you put it under a microscope? and if so look at the tips and see if you find single cells. Thanks :)