''Chrysaora helvola'' is a jellyfish in the family

Pelagiidae The Pelagiidae are a family of jellyfish. Members of the family ''Pelagiidae'' have no ring canal, and the marginal tentacles arise from umbrella margin. Genera There are four genera currently recognized: *Genus ''Chrysaora'' – (14 species) *G ...

. Although still recognized as a valid species by the

World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive list of names of marine organisms. Content The content of the registry is edited and maintained by scientific speciali ...

, its

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. A ...

history is confusing and recent reviews of the genus have not recognized it.

Taxonomy

'' C. fuscescens'' was described in 1835 by Johann Friedrich von Brandt and three years later he described ''C. helvola'' (a name he preferred), noting that ''C. fuscescens'' was its

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are al ...

. This is contrary to the

ICZN Code The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the Int ...

, which states that the oldest name must be used (the younger becomes a junior synonym), but Brandt's publications resulted in confusion and it was only in the 1980s that ''C. fuscescens'' again was recognized as a valid species. Nevertheless, the long history of the name ''C. helvola'' means that it still appears, although recent reviews of the genus have not recognized it. A secondary taxonomic problem related to '' C. chinensis'' of the central

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

, which formerly was listed as a synonym of ''C. helvola''.

References

Chrysaora Animals described in 1838 {{scyphozoa-stub