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Solutions today for reefs tomorrow


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Lesion Terminology and Visualization

Lesion Description Diagram

Lesion Description

  • Color Change – include corals exhibiting change from their normal pigmentation or lack of pigmentation in tissues, typically exemplified by a white color
  • Growth Anomaly – include corals exhibiting excessive or apparently uncontrolled growth of skeleton or soft tissues in relation to adjacent polyps on the same colony
  • Tissue Loss – include corals manifesting absence of tissues with or without intact skeleton
  • Skeletal Damage – structural change to the skeleton caused by anthropogenic, biological agent or environmental events
Lesion Shape

Lesion Shape

  • Annular – of, relating to, or forming a ring
  • Circular – having the form of a circle
  • Irregular – lacking perfect symmetry of form: not straight, smooth, even, or regular
  • Linear – of, relating to, or resembling a line
  • Oblong – deviating from a square, circular, or spherical form by elongation in one dimension
Lesion Distribution

Lesion Distribution

  • Coalescing – to grow together
  • Diffuse – not concentrated or localized
  • Focal – of, relating to, being, or having a focus
  • Linear – of, relating to, or resembling a line
  • Multifocal – arising from or occurring in more than one focus or location
Lesion Location

Lesion Location

  • Apical – situated near the apex or tip of a structure, as in the apical portion of a cell, opposite of basal
  • Central/Medial – lying or extending in the middleCoalescing – to grow together
  • Basal/Peripheral – situated near the base of a structure in relation to a specific reference point, opposite of apical
Lesion Location

Lesion Edges

  • Annular – of, relating to, or forming a ring
  • Distinct – distinguishable to the eye or mind as discrete
  • Indistinct – not sharply outlined or separable
Lesion Margins

Lesion Margin

Lesion Relief

  • Bosselated – marked or covered with small bosses (protuberant parts or bodies)
  • Exophtic – tending to grow outward beyond the surface epithelium from which it originates
  • Nodular – of, relating to, characterized by, or occurring in the form of a nodule (a small node, a circumscribed mass of tissue, or knob-like or knotty swelling of tissue)
  • Umbonate – a rounded elevation

Lesion Assessment

Coral diseases are diagnosed through a tiered process that begins with a field lesion assessment, which describes the gross lesion appearance using the terms listed above without the need for sampling. You can download a field lesion assessment form here. After this initial assessment, it may be possible to to identify a common field name that describes the disease in a particular coral and apply the same terminology to other corals (regardless of species) with similar gross visible signs using the Coral ID Decision Tree.

Coral Disease Assessment Form
Download the coral disease assessment form to accurately record coral lesions in the field.