Image courtesy of NOAA Office of Ocean Exploration and Research, Gulf of Mexico 2017.
sea pens are sediment dwellers. This one has a mysid keeping it company. Mysids are commonly known as opossum shrimp, because they have brood pouches. You can catch a glimpse of the full red brood pouch as two red dots on either side of this mysid’s midsection. Download larger version (jpg, 574 KB).