Great thread - sorry I was away for the weekend and just got back late last night .
OK, let'd do this one - And although it sure would be fun to do as a discussion in person, the fact is that we type..so
The word hermatypic and ahermatypic have long been misused, even in the scientific literature. The answer is in:
Schumacher, Helmut, and Helmut Zibrowius. 1985. What is hermatypic?: a redefinition of ecological groups in corals and other organisms. Coral Reefs 4: 1-9.
Helmut also wrote and article about hermatypic soft corals. Some Sinularia produce suh dense and numerous sclerites in their base that they are larger and more enduring and dense than the skeletons of most stony corals...therefore, even soft corals can be hermatypic. OTOH, many do not recogize Galaxea or Blastomussa as hermatypic because the skeleton is so fragile it just falls apart on the reef over time. A motile gastropod, for example, is not hermatypic because it down not build reef structure. It is calcareous, and *secretes* or *accretes* (not excretes) a skeleton, but is not hermatypic.
hermatypic means reef -building, more or less. Actually means cointributing "significantly" to the structure of a reef
ahermatypic means "not reef -building" more or less
The ability of some reef organisms to photosynthesize greatly enhances their ability in number and amount to calcify, and therefore be hermatypic. Photosynthesis does not, however, equate at all to hermatypic.
Tubastraea micrantha, and in some areas other tubastraea spp., are hermatypic. With the exception of T. micrantha, other Tubastraea spp. are usually not considered herematypic)
So, a photosynthetic organism can be a plant, a microbe, or an animal harboring symbionts.
Symbionts in corals are various zooxanthellae. Thus, the proper term of corals having photosynthetic symbionts is zoxanthellate. Photosynthetic corals are symbiotic corals are zooxanthellate corals, although the latter term is the most correct.
Symbionts in other animals may be things other than zooxanthellae.
So, the great debate rages thus:
If Lophelia, being azooxanthellate, vreates the large caclium structures, are they hermatypes? The technical answer is no, because hermatypic means contributing to reef structure. Let me go further here:
The definition of a coral reef is "massive, wave-resistant, biogenic (has its origins in biologic life) carbonate structures with positive topographic features that are built over millennia, mainly through the actions of hermatypic corals and crustose coralline algae"
The following came as part of one of several recent debates on NOAA's Coral-list:
<<'The term "coral reef" commonly refers to a marine ecosystem in which a
prominent ecological functional role is played by scleractinian corals. A
"structural coral reef" differs from a "non-structural coral community" in
being associated with a geomorphologically significant calcium carbonate
(limestone) structure of meters to hundreds of meters height above
surrounding substrate, deposited by components of a coral reef ecosystem.
The term "coral reef" is often applied to both types of ecosystem or their
fossil remains, although many scientists, especially geomorphologists,
reserve the term for structural coral reefs and their underlying limestone.'>>
It is agreed upon that the term "wave resistant is probably only a hangover from the nautical usage of the word "reef". It is also agreed that Lophelia creates bioherms - not coral reefs, as coral reef has too many other atttributes other than solely the calcium deposits of corals. However, these bioherms also have signficant biodiversity similar to coral reefs, proper.
So, the debate rages on...and why this thread is such a good one.
Let's continue....
Is everyone clear, at least, on hermatypic v. photsynthetic (zooxanthellate)?
Eric
