Comparative biology of four species of glyphocrangonid and crangonid shrimp from the continental slope of the middle Atlantic Bight

Distribution, reproduction, food, and parasites of glyphocrangonid (Glyphocrangon sculpta and Glyphocrangon longirostris) and crangonid (Sabinea hystrix and Metacrangon jacqueti agassizi) shrimp were studied from otter trawl collections on the continental slope of the middle Atlantic Bight. Glyphocrangon sculpta and G. longirostris were found at depths of 2068–2679 m and 1111–2427 m respectively; S. hystrix was found from 452 to 2100 m and M. j. agassizi occurred from 616 to 1430 m. Among all four species, ovigerous females were significantly larger and more numerous than males. Sex ratio patterns expressed as percent male for depth and size are discussed for these species. Reproduction of all species was asynchronous and year-round; ovigerous females were captured during every month. Ovarian growth was continuous, enabling multiple spawnings of small numbers of large eggs. Stomach contents consisted almost entirely of benthic organisms and sediment, but the majority of stomachs were empty. Epibranchial bopyrid isopods were found on G. sculpta, G. longirostris, and M. j. agassizi. Parasite incidence among the species was low but, when present, retarded gonad development in female hosts.