The Joseph Britton Freshwater Mussel Collection User Guide: Specimen Records

Object records contain information concerning the specimen's collection, identification, and physical characteristics. These records were developed from the Elm Fork Natural Heritage Museum records which are based on the original field notes and collecting records for these specimens. This section details the fields and data available in the library records about the individual specimens in the collection.

Linked Terms in Library Records
Terms that appear as links in the library record (green text) will link to a results list of records that contain that term. For instance, subjects and keywords appear as links in the record. By selecting one of these links, a results page will be generated containing objects that include that term in their records. Use this feature to find similar objects and view all objects sharing a particular attribute.

Example Specimen Record

Sample Full Record

Specimen Record Fields

A selection of the most pertinent fields used in the specimen records is given below with an explanation of each field and the possible values it may contain. Additional details about the physical attributes described in the specimen records are available in the Physical Features of Freshwater Mussels page of this guide.

Description - A descriptive paragraph containing the following information about the specimen's physical characteristics: number of valves, shell shape, shell thickness, beak sculpturing, internal and external coloring, external sculpturing, shell length, and shell condition. This paragraph also includes the drainage where this specimen was collected.

  • Number of Valves indicates whether the collection contains both of the valves or just a left/right valve.
  • Shell Shape is defined as one of the following: elliptical, oval, quadrate, rhomboidal, round, or triangular.
  • Shell Thickness is either thick, moderately thick, or thin.
  • Internal Color (Nacre Color) is the color of the inside of a valve. It can be one of the following colors: white, pink, yellow, purple, bluish-white, salmon, blue or purplish-white.
  • Beak Sculpturing is described as either single looped or double looped.
  • External Color is the color of the valve's dermis. It can be one of the following colors: black, dark brown, reddish-brown, brown, tan, olive, off-white, yellow, green, or orange. For valves with no remaining dermis, no external color is listed.
  • External Sculpturing can be smooth or in the form of pustules, ridges, or pustules and ridges.
  • Shell Length is given in four different ranges, 0-60 mm, 60-100 mm, 100-120mm, or greater than 120 mm.
  • Shell Condition is defined as the state the shell was in when collected. Possible values for this field include the following:

    • Live: the specimen was live upon collection.
    • Very-recently dead: Both the dermis and nacre are in good condition. There are internal signs of tissue attachment.
    • Recently dead: Both the dermis and nacre are in good condition. There are no signs of tissue attachment.
    • Relatively-recently dead: The dermis is in good condition. The nacre no longer has any luster and there are signs of algal staining, calcium deposition, or erosion.
    • Long dead: Both the dermis and nacre show some signs of erosion, calcium deposition, or algal staining.
    • Very-long dead: Very little dermis remains and there are significant signs of calcium deposition, erosion, or algal staining.
    • Sub-fossil: No dermis remains and the specimen is obviously eroded.

Physical Description - A physical description of the specimen including the number of valves, internal and external coloring, and shell length.

Collector - Name of the person who collected the specimen.

Contributing Author - The name of the species author.

Owner - The institution that owns the specimen.

Expert - The name of the person who verified the species determination.


  • Keywords - these specimen data have been included in the record as keywords: the common name of the specimen; the water body and drainage where the specimen was collected.

  • Library of Congress Subject Headings - Standard subjects selected from the Library of Congress Subject Headings list. Two subject headings have been applied to all specimens in this collection: Freshwater mussels -- Texas; and Zoological specimens -- Texas.

  • Scientific Name - The specimen's scientific name (Genus, species).


  • Accession or Local Control No. - Contains the catalog number used by the Elm Fork Natural Heritage Museum for specimen identification.

  • Other - Contains the alternate catalog number recorded on the specimen by a previous owner. Applicable for specimens donated to the Elm Fork Natural History Museum or owned by another institution.

  • Archival Resource Key - Archival resource key used to identify the digital object.

Creation Date - Date the specimen was collected.

Place Name - The country, state, and county where the specimen was collected.

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