Trypaea

{{Short description|Genus of crustaceans}}

{{Use dmy dates|date=March 2020}}

{{Use Australian English|date=July 2011}}

{{Speciesbox

| image = Trypaea australiensis.jpg

| image_caption = Trypaea australiensis

| name = Trypaea australiensis

| display_parents = 2

| parent_authority = Dana, 1852

| taxon = Trypaea australiensis

| authority = Dana, 1852

}}

Trypaea australiensis, known as the (marine) yabby or ghost nipper in Australia, or as the one-arm bandit due to their occasional abnormally large arm,{{cite web |url=http://fishnet.com.au/default.aspx?id=234&articleId=2025 |title=Fishnet | Library |accessdate=2016-04-17 |url-status=dead |archiveurl=https://web.archive.org/web/20160508234415/http://www.fishnet.com.au/default.aspx?id=234 |archivedate=8 May 2016}} and as the Australian ghost shrimp elsewhere, is a common species of mud shrimp in south-eastern Australia,{{cite web |url=http://www.environment.gov.au/biodiversity/abrs/online-resources/fauna/afd/taxa/Trypaea_australiensis |work=Australian Faunal Directory |title=Species Trypaea australiensis Dana, 1852 |publisher=Department of the Environment, Water, Heritage and the Arts |date=3 June 2010 |accessdate=6 July 2011}} and may be the only extant species in the genus Trypaea.{{ITIS |id=552836 |taxon=Trypaea Dana, 1852 |accessdate=6 July 2011}}{{cite web |author=Gary Poore |year=2010 |title=Trypaea Dana, 1852 |publisher=World Register of Marine Species |url=http://www.marinespecies.org/aphia.php?p=taxdetails&id=465344 |accessdate=6 July 2011}} T. australiensis is a popular bait used live or frozen by Australians targeting a range of species.{{cite book |url=http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0005/375890/Ghost-nipper.pdf|chapter=Ghost nipper (Trypaea australiensis) |pages=143–144 |editor=K. Rowling, A. Hegarty & M. Ives |year=2010 |title=Status of Fisheries Resources in NSW 2008/09 |publisher=NSW Industry & Investment |location=Cronulla}} It grows to a length of {{convert|6|cm}} and lives in burrows in mudflats or sandbanks, especially in or near estuaries.{{cite web |url=http://www.sealifebase.org/summary/SpeciesSummary.php?id=14764 |title=Trypaea australiensis Dana, 1852, Australian ghost shrimp |work=SeaLifeBase |date=23 March 2010 |accessdate=6 July 2011}}