Oncaea venusta

{{Short description|Species of crustacean}}

{{Speciesbox

| image = Oncaea venusta.jpg

| image_upright = 0.6

| taxon = Oncaea venusta

| authority = Philippi, 1843

}}

Oncaea venusta is a species of copepod with a cosmopolitan distribution, but lacking from the Arctic Ocean.{{cite web |author=Ruth Böttger-Schnack, Juliana Kouwenberg & Geoff Boxshall |year=2011 |title=Oncaea venusta Philippi, 1843 |editor=T. Chad Walter & Geoff Boxshall |work=World Copepoda database |publisher=World Register of Marine Species |url=http://www.marinespecies.org/aphia.php?p=taxdetails&id=128954 |accessdate=June 24, 2011}} Females are {{convert|1.1|-|1.3|mm|abbr=on}} long, while males are only {{convert|0.8|-|1.0|mm|abbr=on}} long.{{cite book |author=William S. Johnson, Dennis M. Allen & Marni Fylling |year=2005 |title=Zooplankton of the Atlantic and Gulf Coasts: a Guide to their Identification and Ecology |publisher=Johns Hopkins University Press |isbn=978-0-8018-8168-8 |chapter=Poecilostomatiod [sic] copepods |pages=160–161 |url=https://books.google.com/books?id=A8iGP6acatgC&pg=PA160}} The front of the head is unusually wide, and the body is brightly coloured, usually yellow–orange, but sometimes red. O. venusta feeds on a variety of zooplankton and phytoplankton.