January 2003

"JODC Taxonomic Code of Marine Organisms (Plankton)" is a digital code for marine organisms, mainly zooplankton, developed to realise efficient management of information through the use of computers. The JODC Taxonomic code has registered 8,088 marine organisms (8,242 including subspecies) in the 2001 Edition.

1. Structure of the Marine Taxonomic Codes

Species of all marine organisms, registered in the JODC, are listed in the order of taxonomic hierarchy as shown below.

Explanation of details to follow.

Field Category Description
Name Code Organism name code,
00001 to 99999 (numerals only)
Taxonomic Code Organism taxonomic name code,
01000000000000 to 99999999999999 (numerals only)
06-07 Phylum (Division)
08-09 Class
10-11 Order
12-13 Family
14-15 Genus
16-17 Species
18-19 Subspecies (Variety, Form)
Name Flag Blank : Scientific name (Nomen)
J: Japanese name
D: Doubtful species inhabited around Japan
S: Synonym
L: Larva
Z: Larva Synonym
Organism Name Scientific name, Japanese name, Vernacular name, etc.

2. Limits of Species

Basically, all marine organisms are registered in taxonomic hierarchy from Phylum to Order. However, the following are not represented because these do not often occur in marine plankton:

Below Order, the JODC code is focused on the planktonic forms of marine organisms. Benthos, Nekton, as well as parasitic organisms are represented together in groups of species that are limited in its classification.

The new 2001 Edition refers to the "Japanese Marine Plankton Reference Chart" (Chihara Mitsuo and Murano Masaaki, 1996, Tokai University) and adopts the latest accepted view of plankton taxonomy in addition to the "JODC Marine Organism Codes (Plankton)" that was published in 1988.

3. Coding Method

Each species is identified by code composed of two sets of numbers. The two types of code sets, "Taxonomic Code" and "Name Code", are prepared as follows:

  1. Taxonomic Code

    The Taxonomic Code is a 14-digit integer. A 2-digit integer is assigned to each rank such as Phylum and Class. The code set is designed to match the most recent accepted hierarchy for planktonic organisms. However, there are arrangements to reflect relationships in the taxonomy of each organism. For example, if a Suborder consists of a large number of families, it will be used instead of the Order.
    The first 2 digit integers are set as follows:
    Kingdom Monera 01 - 09
    Kingdom Protoctista 11 - 39
    Kingdom Plantae 46 - 49
    Kingdom Animalia 51 - 96
  2. Name Code

    A Name Code is a 5-digit integer. It is a one-to-one correspondence with the name of the organism genus or species. In contrast with "Taxonomic Code”, a Name Code will never change even if the species changes genus or it’s name becomes invalid. Consequently, this code set has the following advantages:
    1. A Name Code consists of less digits than a Taxonomic Code. When digitising data, including names of species, which is recorded in an observation chart, "Name Code" will reduce the number of input errors and save the trouble of converting to "Taxonomic Code".
    2. Some organisms are known by several names such as the use of a synonym or it’s Japanese name. Because an organism is given a single Taxonomic Code, when the name is converted to the Taxonomic Code, the information from the original observation would be lost if the original name was not preserved by the Name Code.
    3. There may be a change in the status of an organism whose taxonomy is unknown. Using the Name Code will enable the database to cope with taxonomy changes.

  3. Name Flag

    The Name Flag indicates the origins of the organism name. Following the explanation of each flag:

    " " a blank indicates that this is the scientific name.
    "J" indicates the most common Japanese name used for this organism.
    "S" indicates the synonym of its scientific name and/or the synonym to its Japanese name. However, in case that it separates in to several species and its scientific name changes in the partial sea region such as of the adjacent sea of Japan while its species name of the base production region remains the same, a SENSU personnel name is attached after its specie name in order to distinguish it as the synonym only for the population in the partial sea region. Furthermore, a common species group name that may have become invalid may still be registered with the "S" flag under the existing superior specie group that resembles the organized species.
    "D" indicates a species that is not recognised to occur in Japanese water, a doubtful species. In the past, old Japanese books frequently and carelessly reproduced illustrations of foreign species as occurring in Japanese water. These illustrated books were difficult to ignore due to the eye-catching publications.
    "L" indicates Larva.
    "Z" indicates the synonym of larva.

  4. Organism Name

    The position of the scientific names are shifted to right by one letter space for each taxonomic rank (Phylum, Class, Order, Family) starting from the Phylum to the Family. A shift to the right stops at the Family class and is not applied to any classification below the Family class.

  5. Explanation of "sp."

    A generic name differs from the classification group name above the Family class by not having a common rule to the changes in their word endings. Considering this, "sp." is added at the end of all names at the time of register in order to enable a distinction. Consequently, though this may not be the proper format, "sp." is attached even to the genera with one species.

4. Macrotaxonomy

Both the Members of the Marine Organisms Data Management Advisory Group and consulted experts from around the world have expressed different views on plankton hierarchy. In the future, it may be necessary to alter or adjust the taxonomy of marine organisms to reflect changes in perception.