Statolith Morphometrics Can Discriminate among Taxa of Cubozoan Jellyfishes

PLoS One. 2016 May 18;11(5):e0155719. doi: 10.1371/journal.pone.0155719. eCollection 2016.

Abstract

Identification of potentially harmful cubomedusae is difficult due to their gelatinous nature. The only hard structure of medusae, the statolith, has the potential to provide robust measurements for morphometric analysis. Traditional morphometric length to width ratios (L: W) and modern morphometric Elliptical Fourier Analysis (EFA) were applied to proximal, oral and lateral statolith faces of 12 cubozoan species. EFA outperformed L: W as L: W did not account for the curvature of the statolith. Best discrimination was achieved with Canonical Discriminant Analysis (CDA) when analysing proximal + oral + lateral statolith faces in combination. Normalised Elliptical Fourier (NEF) coefficients classified 98% of samples to their correct species and 94% to family group. Statolith shape agreed with currently accepted cubozoan taxonomy. This has potential to assist in identifying levels of risk and stock structure of populations in areas where box jellyfish envenomations are a concern as the severity of envenomation is family dependent. We have only studied 12 (27%) of the 45 currently accepted cubomedusae, but analyses demonstrated that statolith shape is an effective taxonomic discriminator within the Class.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cubozoa / anatomy & histology*
  • Cubozoa / classification*
  • Discriminant Analysis
  • Fourier Analysis

Associated data

  • Dryad/10.5061/dryad.n14ph

Grants and funding

This research was supported by a grant from the Australian Lions Foundation to CJM and Marine and Tropical Science Research Facility funding to MJK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.