Assessment of investigation techniques for scyphozoan statoliths, with focus on early development of the jellyfish Sanderia malayensis

Abstract

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 591:37-56 (2018) - DOI: https://doi.org/10.3354/meps12292 Assessment of investigation techniques for scyphozoan statoliths, with focus on early development of the jellyfish Sanderia malayensis Anneke Heins1,2,*, Ilka Sötje3, Sabine Holst2 1University of Oldenburg, Institute for Biology and Environmental Sciences, 26129 Oldenburg, Germany 2Senckenberg am Meer, German Center for Marine Biodiversity Research, 20146 Hamburg, Germany 3University of Hamburg, Biocenter Grindel, Zoological Institute, 20146 Hamburg, Germany *Corresponding author: anneke.heins@uni-oldenburg.deAdvance View was available online October 6, 2017 ABSTRACT: Statolith ageing techniques provide a useful tool in the study of age, growth, and population structure of several marine organisms. Previous investigations on scyphozoan statoliths demonstrated increased statolith numbers and size with increasing medusa size, as well as taxon-specific variations in statolith shape. Thus, statoliths are potentially useful for age determination and taxonomic studies on medusae. Unfortunately, studies on statoliths are difficult because of the fragile structure of the numerous tiny crystals and their hygroscopic nature. We evaluated the potential of various modified study techniques for scyphozoan statocysts and statoliths applied to early medusa stages of Sanderia malayensis Goette, 1886. Light microscopy was suitable to follow the increase of statolith numbers and sizes with age and allowed differentiation of various statolith shape types, which were confirmed by scanning electron microscopy. The use of the fluorescent marker calcein provided direct evidence for measurable statolith growth. Our results indicated that statoliths stopped growing after reaching a certain size while additional statoliths developed in the basal region of the statocyst. Micro-computed tomography data allowed visualization and morphometric measurements of statoliths, revealing interspecific differences that may be useful for phylogenetic studies. Statolith numbers were positively correlated with medusa age and bell diameter. Thus, statolith analyses could provide information on medusa age or size, both of which are important parameters for population structure analyses that are difficult to assess with currently applied techniques. Our study provides methodological bases for future studies to reveal further potential of scyphozoan statolith investigations for phylogenetic and ecological studies. KEY WORDS: Cnidaria · Statocyst · Medusa · Slide scanner · Micro-tomography · Calcein · Scanning electron microscopy · SEM · Energy-dispersive X-ray spectroscopy · EDX Full text in pdf format Supplementary material PreviousNextCite this article as: Heins A, Sötje I, Holst S (2018) Assessment of investigation techniques for scyphozoan statoliths, with focus on early development of the jellyfish Sanderia malayensis . Mar Ecol Prog Ser 591:37-56. https://doi.org/10.3354/meps12292 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 591. Online publication date: March 19, 2018 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2018 Inter-Research.