The articulated corallines
constitute a diverse group of branched, calcified red algae. Found in nearly
all of the world's marine habitats, articulates primarily occupy intertidal
and subtidal coastal areas. Spotting these algae in even deeper waters is
not uncommon though. Their characteristic branching and calcium carbonate
cell walls make them difficult to miss.
Most articulates grow
as individual plants on rocks or granular substrates. However, some of these
algae can grow as epiphytes, growing on the shells of benthic marine organisms
or other algae. Corallines often grow bunched together in clusters but some
species are distributed more sparsely.
Corallina is just one example of
an articulated coralline.
All corallines share common
characteristics, including calcification, reproduction in conceptacles,
and filamentous organization. The primary characteristic that separates
the articulates from their crustrose brethren is the presence of flexible,
uncalcified joints called genicula. These joints give the articulates the
flexibility needed to withstand the fierce and volatile motions that come
with life in the oceans.
Even though the subfamilies
of articulates have many similarities, they also have bear some striking
differences. The most notable features that distinguish groups of geniculates
from each other are branching patterns and thickness, location of reproductive
organs, and cell organization within tissues. Sometimes it is impossible
to differentiate amongst species without sectioning samples and looking
at them under a microscope.
colony of articulated corallines found ninety feet deep in the Monterey
I hope this site presents
a clear and interesting portrait of the articulates. They are a most fascinating
group of organisms. Below are links to broad categories within which information
is organized into specific topics. Links back to these broad topics can
be found at the bottom of each page. Please enjoy.
Evolution | Ecology | Systematics | Mechanics | Pigmentation | Morphology | Reproduction | Life
History | References | Procedures Acknowledgements | Main
Ian Ehrenreich. All rights reserved.