PACIFIC CORAL REEF ECOSYSTEM BENTHIC HABITAT MAPPING CLASSIFICATION SCHEME
            ** SCLERACTINIAN CORAL CLASSIFICATIONS      
System[1] code[2] Zone[3] code[4] Percentage of Substrate code[5] Living Cover[6] code[7] Coral Genera  (HI only) code[8] Coral Growth Morphology code[9] Holes[10] code[11]
basalt island[12] bi intertidal [13] it UNCONSOLIDATED[14] u seagrass[15] sg Pocillopora pp Massive m no cavities no
sea stack[16] ss lagoon[17] lg      mud[18] m non-scleractinian coral[19] ns Porities (massive & encrusting) pm Plate-like p few small cavities  fs
carbonate island[20] ci reef flat[21] rf      sand[22] s scleractinian coral**[23] sc Porities compressa pc Encrusting e many small cavities ms
closed atoll[24] ca back reef[25] br   coralline algae[26] ca Montipora m Branching b few large cavities  fl
open atoll[27] oa reef crest[28] rc     coral or coralline algae[29] cc Acropora a Columnar c many large cavities  ml
submerged bank/reef[30] sb fore reef[31] fr HARDBOTTOM[32] h macroalgae[33] ma Other live coral ol Free-living f few sml and lrg cavities  fsl
continental reef[34] cr shelf[35] sh     rubble[36] rb turf algae ta unencrusted coral ue     many sml & lrg cavities  msl
    escarpment[37] es     boulder[38] b unclassified algae[39] ua         many sml & few lrg cavities msf
    land[40] ln     rock[41] rk emergent vegetation[42] ev            
            man-made structure[43] mm Giant Clam gc            
          Other non-mobile inverts[44] nm            
            None[45] no            
                           
                           
unclassified[46] uc unclassified[47] uc unclassified[48] uc unclassified[49] uc unclassified[50] uc unclassified[51] uc unclassified[52] uc
[1]
The "system" category includes the the largest scale of interest here and encompasses entire coral reef ecosystems.
[2]
Code number to enter into classifcation template.
[3]
The "Zones" category includes some indication of the location of the feature relative to the shoreline and open ocean, and may include a description of seafloor shape as well.

[4]
Code number to enter into classifcation template.
[5]
Code number to enter into classifcation template.
[6]
The  cover" category quantifies  the occurance of macroscopic organisms growing on and attached to the sea floor. Quantities listed are the total percentage of seafloor that the organism covers. They may be expressed as measured percentages, or  binned into the following groups:

0% = none;
0> to <= 10% = sparse;
>10 to <= 50% = moderate
 >50% to <= 90% = dense;
>90% = continuous

The organisms listed here include those that have been observed colonizing the seafloor in Pacific coral reef ecosystems. Other organisms may be included as they are encountered.

Turf algae covers most hard substrate not otherwise colonized in these ecosystems. Too small to be readily identified in most benthic photographs, it is not included in this listing.

It is  not be practical to  include rarely observed species in these gereral-purpose maps, and it is recommended that entries in this category be limited to more commonly-encountered benthic colonizers.  The occurrence of rare species can be recorded in data layers designed for that purpose.
[7]
Code number to enter into classifcation template.
[8]
Code number to enter into classifcation template.
[9]
Code number to enter into classifcation template.
[10]
Although very hard to detect and rigorously quantify, the strong association of important fish and invertebrate species with cavities in the seafloor makes them of particular biological importance. These categories have been modified slightly from those developed by the Hawaii Undersea Research laboratory.
[11]
Code number to enter into classifcation template.
[12]
An island of volcanic origin and in which some volcanic material is still subaerially visible. Also known as high islands.
[13]
That portion of the substrate that is both subaerially exposed and underwater during some portion of a normal lunar tidal cycle.
[14]
Unconsolidated sediments are defined here as being composed of predominantly sand-size or smaller (<2 mm mean diameter) grains. It may be hard, without actually moving material around on the seafloor, to distinguish between rubble or boulders or solid rock. Rubble and boulders may also be covered by benthic algae or other colonizing organisms, further conplicating their differentiation. Accordingly, they are included here within the "hardbottom" category.  Sand-sized or smaller sediments, on the other hand, are relatively mobile  and tend to preclude the settlement and growth of many benthic colonizing organisms, making them easier to distinguish from rubble, boulders, and solid rock.

If you can not distinguish whether most of the material is composed of sand or mud sized grains, just go with "unconsolidated."
[15]
The percentage of live seagrass visible on the surface of the seafloor.
[16]
A steep-sided, mostly barren, rock island formed by the eroded remnants of a larger formation, e.g., La Perouse Pinnacle, Necker Island, and Gardner Pinnacles.
[17]
A shallow body of water near but separated from the open ocean by a barrier reef or other structure.*
[18]
Sediment with a grain size of < 1/16 mm.
[19]
The percentage of seafloor covered by non-scleractinian coral fauna. This category includes hydrocorals, hydroids, soft corals, sea fans, sea pens, anemones, black corals, sponges, oysters and other encusting bivalves and molluscs, etc.
[20]
An island composed of carbonate reef and detrital material without any volcanic structure evident above sea level (although it may be built on a volcanic edifice. Typically of low elevation, these are also referred to as "low islands."
[21]
Flat and shallow (typically depths less than a few meters) areas shoreward of a reef and characterized by coarse rubble, algae and sand.**
[22]
Unconsolidated sediment composed predominantely of grains with a mean diameter between  of ≥ 1/16 mm  and < 2 mm.
[23]
The percentage of live scleractinian coral covering the seafloor. These data are broken out as a separate layer as well.
[24]
A ring-shaped coral reef that surrounds a lagoon, is surrounded by the open sea, and contains one or more passages.
[25]
The area between a reef and the shoreline, especially that portion of a reef structure inhabited by reef-building organisms and landward of the reef crest. In a barrier reef setting the landward boundary of the back reef is the seaward edge of the lagoon floor. In a fringing reef environment, the landward edge of the back reef (if present at all) may be marked by a shift from heavy colonization by reef building organisms to a  zone of sparse colonization of the reef flat.* ** ***
[26]
The percentage of seafloor covered by living  coralline algae.
[27]
An atoll in which much of the perimeter reef is absent.
[28]
A band or line that is typically parallel to the shoreline and represents the highest elevations of a fringing or barrier reef. The reef crest is often near mean sea level and may be subaerially exposed at low tide.
[29]
The percentage of seafloor covered by growth that can be identified as either coral or coralline algae, but not  differentiated as to which of those it is.
[30]
A raised portion of the sea floor occurring at shallow depth but below the intertidal zone.*
[31]
The upper part of the outer or seaward slope of a reef, extending from the reef crest or seaward edge of the reef flat down to an area with a reduced slope marking the start of a shelf, or the point at which abundant growth of coral and coralline algae is restricted due to light limitation.* ***
[32]
Hard, consolidated substrate. Note that rubble and boulder categories are typically classified as large-grained sediments. However, they may be covered by algae, corals or other benthic colonizers and therefore indistinguishable from consolidated rock Accordingly, they are included within the hardbottom sub-category.
[33]
The percentage of macroalgal growth that is large enough to be readily visible to a diver a few meters above the seafloor. This category excludes low turf algae, which colonize most hard substrates that are not otherwise colonized, but are too small to be seen in many optical and diver-based surveys.
[34]
A coral reef ecosystem located adjacent to a continental land mass.
[35]
A generally flat,  benchlike,  projecting ledge of rock.*
[36]
Fragments of coral or other carbonate reef material, typically of cobble size but with finer and coarser sediments mixed in.
[37]
The edge of a bank, island, or shelf where depths increase rapidly into deep oceanic water.***
[38]
Substrate composed predominantly of pieces of rock with a diameter of 256 mm or larger.
[39]
This category is used when the observer dan identify living cover as either macroalgae, turf, or clacareous algae, but is unable to distinguish which.
[40]
Any portion of the substrate at an elevation above the intertidal zone.
[41]
Consolidated, hard substrate or boulders   (fragments with a mean diameter ≥ 256 mm) composed of any type of volcanic or carbonate rock.
[42]
The percentage of the seafloor covered by vegetation, such as mangrove, that is located seaward of the low tide line but is also subaerially exposed.
[43]
     Most hard benthic substrates in the photic zone and not otherwise colonized will rapidly become colonized by turf algae.  However, very often turf algal communities are often too small to be distinguishable, in which case the substrate type is listed.
     As with sediments, man-made structures may be listed under "Substrate Composition" and may also be appropriate "Cover" category entries.
[44]
Bivalves, molluscs, or other sessile invertebrates that are fixed to the substrate.
[45]
Most hard substrates not otherwise colonized are assumed to have turf algae, so this category is limited to sandy or substrates.
[46]
A particular data entry may be unclassified because image quality was poor, because not enough of an area was seen to classify, etc.
[47]
A particular data entry may be unclassified because image quality was poor, because not enough of an area was seen to classify, etc.
[48]
A particular data entry may be unclassified because image quality was poor, because not enough of an area was seen to classify, etc.
[49]
A particular data entry may be unclassified because image quality was poor, because not enough of an area was seen to classify, etc.
[50]
A particular data entry may be unclassified because image quality was poor, because not enough of an area was seen to classify, etc.
[51]
A particular data entry may be unclassified because image quality was poor, because not enough of an area was seen to classify, etc.
[52]
A particular data entry may be unclassified because image quality was poor, because not enough of an area was seen to classify, etc.