Scientists aim to describe a single 'tree of life' that reflects the evolutionary relationships of living things. However, evolutionary relationships are a matter of ongoing discovery, and there are different opinions about how living things should be grouped and named. EOL reflects these differences by supporting several different scientific 'classifications'. Some species have been named more than once. Such duplicates are listed under synonyms. EOL also provides support for common names which may vary across regions as well as languages.

Preferred marks the preferred classification for this taxon.

Recognized By Rank Classification
NCBI Taxonomy
view in classification
Species Import
BOLDS resource for species-level taxa
DiscoverLife map resource
  • Halgerda willeyi
EOL Group on Flickr
view in classification
BOLDS images II Species
Inventaire National du Patrimoine Naturel Species
AquaMaps Resource
OBIS Environmental Information
  • Halgerda willeyi Eliot, 1904
OBIS depth range resource
Ocean Genome Resource- genomic DNA available
Wikimedia Commons


EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

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