MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 583:149-161 (2017) - DOI: https://doi.org/10.3354/meps12335 Three-stage lipid dynamics during development of planktotrophic echinoderm larvae Thomas A. A. Prowse1,4, Mary A. Sewell2, Maria Byrne1,3,* 1School of Medical Sciences, University of Sydney, NSW 2006, Australia 2School of Biological Sciences, University of Auckland, Auckland, New Zealand 3School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia 4Present address: School of Mathematical Sciences, The University of Adelaide, SA 5005, Australia *Corresponding author: maria.byrne@sydney.usyd.edu.au ABSTRACT: The eggs of marine species with planktotrophic development must contain, at a minimum, sufficient material for production of a larva that can then sequester additional materials to grow and metamorphose successfully. In echinoderms, lipids perform crucial energy storage and structural functions during larval construction, but their roles during later development and metamorphosis are poorly understood. We investigated lipid-class depletion in early development and accumulation in late development and a lipid nutritional condition index (energetic lipid:sterol ratio) from the egg to the juvenile in the sea star Patiriella regularis and the sea urchin Heliocidaris tuberculata. Three phases were identified: (1) rapid depletion of energetic lipids during embryogenesis and the facultative feeding period (between feeding competence and exhaustion of energetic lipid reserves), (2) larval growth with no improvement in lipid nutritional condition, and (3) rapid lipid accumulation in advanced larvae prior to metamorphosis. Maternally derived energetic lipids were depleted more slowly in fed than unfed larvae but were still exhausted quickly. Patiriella regularis improved their lipid condition index during Phase 3 by accumulating energetic lipid (triacylglycerol [TAG], diacylglycerol ether [DAGE]) reserves that were then partially used to fuel settlement and metamorphosis. In contrast, Heliocidaris tuberculata did not accumulate TAG or DAGE during this phase, suggesting that metamorphosis is fuelled by other reserves, which we hypothesize may be phospholipids. KEY WORDS: Larval development · Maternal provisioning · Juveniles · Sea stars · Sea urchins Full text in pdf format PreviousNextCite this article as: Prowse TAA, Sewell MA, Byrne M (2017) Three-stage lipid dynamics during development of planktotrophic echinoderm larvae. Mar Ecol Prog Ser 583:149-161. https://doi.org/10.3354/meps12335 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 583. Online publication date: November 16, 2017 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2017 Inter-Research.