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Examples of identifying species


Identifying a species can range from being very easy, to nearly impossible with the naked eye.  Soft corals notoriously fall into the difficult to ID.  As a result, we all need to be very cautious and avoid using assumptions when ID'ing a soft corals. 


Below are some anatomy features to corals, as well as some examples of soft coral ID, to demonstrate the potential difficulty.

Genus Dendronephthya

Genus Dendronephthya

This is a very complex genus to ID as nearly all ID's require a macro shot of the poly area, or a microscope. 


I have added one ID I believe to be accurate based on the description of the original document.


Below information is based on original description: Found here

There are 3 "types" of Dendronephthya; Glomerate, Divaricate and Umbellate as described below by the original description. 


"Kükenthal has divided this difficult genus into three main groups: (I) Glomerate; (II) Divaricate; (III) Umbellate, giving precision to similar suggestions by previous workers such as Holm. 


 I.  The Glomerate are characterized by:

  • a. The comparatively slight branching of the polyparium;
  • b. The grouping of numerous bundles of polyps into roundish bunches which make the surface of the polyparium entirely irregular.
  • c. There is a marked definiteness about the Glomerate division which suggests "naturalness" and makes it easy to refer to a species to the group. Text-fig. 1 is a diagrammatic illustration of what is meant by the Glomerate habit of growth.

II.  The Divaricate are characterized by:

  • a. The profuse branching of the polyparium;
  • b. The length and slenderness of the twigs;
  • c. The divergent separateness of the polyp bundles;
  • d. The absence of anything that can be called bunches of the Glomerate type or umbels of the Umbellate type.


    It should be noted that a Divaricate polyparium may have a continuous contour like that of a well-pruned tree (see diagram).

III.  The Umbellate are characterized by:

    a   The umbel like or sometimes corymb like aggregates formed by terminal twigs, heads of the umbels being bundles of polyps

    b   The disposition of all or most of the polyp heads on the surface of the colony.

Identifying which is a Glomerate, Divaricate or Umbellate form is relatively simple. However, if one goes deeper into a single form, it will prove to be very difficult.


Here is an example of a specie I am reasonably certain is accurate, thanks to a great photo provided by Cornelis Opstal, via Dreamstime.com.


The Diagnosis of Dendronephthya suensoni, found on page 52 is as follows:


"Divaricate; outline irregular; not obviously flattened; polyps in little groups (4 - 10 ), distinctly scattered; polyps stalks medium; supporting bundle medium; point spicules one pair only, of which one member is a long projecting curved spindle associated with a much smaller one at its base; crown of some 6 rows of horizontally disposed spindles; grade VI; spicules: canal-walls show numerous forms with greatly developed thorns; colour: cortex and polyps have deep red spicules, polyps grey-yellow."

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