Duobrachium is a monotypic genus of comb jellies (Ctenophora) belonging to the order Cydippida, family unknown.
The only known species is Duobrachium sparksae.
During Océano Profundo 2015 ("Deep Ocean 2015"), an expedition to explore seamounts, oceanic trenches and submarine troughs off Puerto Rico, shore-based scientists of the National Oceanic and Atmospheric Administration's (NOAA's) National Marine Fisheries Service, using the remotely operated undersea vehicle Deep Discoverer deployed from the research ship NOAAS Okeanos Explorer, captured video footage of three specimens of Duobrachium sparksae, a previously unknown species of comb jelly (Ctenophora), on 10 April 2015.
Deep Discoverer filmed the specimens moving just above the sea floor in the Arecibo Amphitheater inside the Guajataca Canyon, north-northwest of Puerto Rico, at a depth of 3,910 metres (12,828 ft).
The NOAA scientists announced the discovery of Duobrachium sparksae in November 2020.
