Macrourus berglax shrimps, amphipods, polychaete worms, bivalve molluscs, isopods, brittle stars, other echinoderms and comb jellies. The roughhead grenadier is a slow growing fish. The females mature at an age of about 14 years and a length of while males reach maturity at a length of . The potential fecundity of the female is 17,000 to 56,000 eggs. The eggs are laid in batches and spawning takes place at any time of year, with a peak in late winter and early spring. The roughhead grenadier is landed as a by-catch when fishing for Greenland halibut ("Reinhardtius hippoglossoides") and Atlantic halibut ("Hippoglossus hippoglossus").
Flat pebblesnail Flat pebblesnail The flat pebblesnail ("Lepyrium showalteri") is a species of freshwater snail, an aquatic gastropod mollusk in the family Lithoglyphidae. This species is endemic to the United States. This snail has been listed as endangered on the United States Fish and Wildlife Service list of endangered species since October 28, 1998. "Lepyrium showalteri" is the only species in the genus Lepyrium. "Lepyrium showalteri" is the type species of the genus "Lepyrium". Lepyriidae is a synonym of Lithoglyphinae. The flat pebblesnail is a small snail in the family Lithoglyphidae; however, the species has a large and distinctive-looking shell. This snail's