E-Fauna Photo Gallery

Briarosaccus auratum  (Parasitic Barnacle)

Photo of Briarosaccus auratum by Aaron Baldwin
© Aaron Baldwin (Photo ID #90313)

Photographer's Submitted Details

Photo Location Endicott Arm, Alaska Photographer Aaron Baldwin
Habitat Inside Lithodes aequispinus king crabs
Photo Date February 22, 2016 Upload Date February 22, 2016
Elevation (m)
UTM Zone # Latitude
UTM Easting Longitude
UTM Northing Photo ID # 90313
Notes This is the embryo-containing sack of the bizarre parasitic barnacle Briarosaccus. The actual barnacle is a fine branching root-like structure that fills the body of the crab and infiltrates every organ system. When the larvae are mature they will leave the externae to go infect new crabs. The infection is permanent. Prior to infection, this crab was a male. The barnacle absorbs the testes and secretes hormones that makes the crab develop female characteristics. Formerly Briarosaccus callosus.


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