Cirrothauma murrayi

{{Short description|Species of octopus}}

{{Speciesbox

| image = CirrothaumaMurDraw2.jpg

| image_alt = A drawing of C. murrayi that shows its mantle, arms, and swimming fins.

| status = DD

| status_system = IUCN3.1

| status_ref = {{cite iucn |author=Lyons, G. |author2=Allcock, L. |date=2014 |title=Cirrothauma murrayi |volume=2014 |page=e.T163011A963624 |doi=10.2305/IUCN.UK.2014-3.RLTS.T163011A963624.en |access-date=20 November 2021}}

| genus = Cirrothauma

| species = murrayi

| authority = Chun, 1911

}}

Cirrothauma murrayi, the blind cirrate octopus,{{cite web |title=Cirrothauma murrayi Chun, 1911 |url=http://marinespecies.org/aphia.php?p=taxdetails&id=139174#vernaculars |website=World Register of Marine Species |publisher=MolluscaBase}} is a presumably blind octopus whose eyes can likely sense light, but not form images. It has been found worldwide, usually {{convert|1500|to|4500|m}} beneath the ocean's surface, but a single specimen was collected in the Arctic immediately below the sea ice.{{cite web|last1=Vecchione|first1=Michael|last2=Young|first2=Richard|title=Cirrothauma murrayi|url=http://tolweb.org/Cirrothauma_murrayi/20099|website=Tree of Life Web Project|access-date=12 March 2018|ref=Tree of Life}}{{Cite journal |last=Aldred |first=R. G. |last2=Nixon |first2=Marion |last3=Young |first3=John Zachary |date=1983 |title=Cirrothauma murrayi chun, a finned octopod |url=https://royalsocietypublishing.org/doi/10.1098/rstb.1983.0021 |journal=Philosophical Transactions of the Royal Society of London. B, Biological Sciences |volume=301 |issue=1103 |pages=1–54 |doi=10.1098/rstb.1983.0021|url-access=subscription }} Like other cirrates, it has an internal shell, muscular fins for swimming, and a web connecting the arms.{{cite web|last1=Mangold|first1=Katharina|last2=Vecchione|first2=Michael|last3=Young|first3=Richard|title=Cirrata|url=http://tolweb.org/Cirrata/20086|website=Tree of Life Web Project|access-date=12 March 2018|ref=Mangold}}

The species was first caught by an expedition led by Sir John Murray in 1910, and it was later named in honor of Murray. It was described by German marine biologist Carl Chun in 1911.

The diet of this species is unknown, but like other cirrate octopods, the buccal mass, esophagus, and stomach of Cirrothauma murrayi suggest whole (but very small) organisms, especially small crustaceans, are part of its diet (it has only a vestigial trace of a radula). The enzymatic action of salivary excretions separates the crustacean's musculoskeletal attachments and allows for the tissue to be removed, leaving the exoskeleton of the crustacean undamaged.

Molecular work suggests that Cirrothauma murrayi may comprise two similar species,{{Cite journal |last=Verhoeff |first=Tristan Joseph |last2=O'Shea |first2=Steve |date=2025-03-14 |title=A new southern hemisphere species of Cirroteuthis (Octopoda: Cirrata: Cirroteuthidae), and re-evaluation of the taxonomic status of Cirroteuthis hoylei Robson, 1932 |url=https://www.foliamalacologica.com/A-new-southern-hemisphere-species-of-Cirroteuthis-Octopoda-Cirrata-Cirroteuthidae,199484,0,2.html |journal=Folia Malacologica |language=english |issue=1 |doi=10.12657/folmal.033.003 |issn=1506-7629|doi-access=free }} indeed work on the species by Aldred et al. (1983) found that some specimens had sucker counts in the upper 30's per arm while others had counts around 60 per arm (despite the animals being similar in size), which may suggest two otherwise similar species.