Biochemical and energetic composition of bathyal echinoids and an asteroid, holothuroid and crinoid from the Bahamas
McClintock, JB.; Cameron, JL.; Young, CM.
Marine Biology (Berlin) 1052: 175-183
ISSN/ISBN: 0025-3162 DOI: 10.1007/bf01344284
The biochemical and energetic composition of body components of ten species of bathyal echinoids, and an asteroid, a holothuroid and a stalked crinoid were determined from individuals sampled from a variety of deep-water sites near the Bahamas (north Caribbean Sea) in October 1988. When compared with other studies of echinoderms, no geographic- or depth-related differences in biochemical or energetic composition were found. Body-wall tissue were composed primarily of skeletal material (mineral ash), but were comparatively high in organic material in the echinothuriid echinoids, and the asteroid and holothuroid. Gut tissues and pyloric cecae had high levels of lipid and protein, indicating their potential role in nutrient storage. Body-wall tissues were generally low in energy, but were highest in the echinoids Araeosoma belli (7.7 kJ g-1 dry wt) and Sperosoma antilense (8.0 kJ g-1 dry st), the asteroid Ophidiaster alexandri (8.9 kJ g-1 dry wt), and the holothuroid Eostichopus regalis (13.1 kJ g-1 dry wt). Energy levels of gut and pyloric cecal tissues were two to three times higher than those of body-wall tissues. Total somatic tissue energy values varied greatly among species, ranging from 1.5 kJ in the echinoid Aspidodiadema jacobyi to 142.1 kJ in E. regalis. As the bathyal echinoderms examined in this study occur in great abundance, they represent a significant reservoir of organic and inorganic materials and energy in deep-water benthic systems.