Fukuyoa paulensis gen. et sp. nov., a new genus for the globular species of the dinoflagellate Gambierdiscus (Dinophyceae)

PLoS One. 2015 Apr 1;10(4):e0119676. doi: 10.1371/journal.pone.0119676. eCollection 2015.

Abstract

The marine epiphytic dinoflagellate Gambierdiscus is a toxicologically important genus responsible for ciguatera fish poisoning, the principal cause of non-bacterial illness associated with fish consumption. The genus currently contains species exhibiting either globular or anterior-posteriorly compressed morphologies with marked differences in cell shape and plate arrangement. Here we report a third globular, epiphytic and tychoplanktonic species from the coasts of Ubatuba, Brazil. The new species can be distinguished from G. yasumotoi and G. ruetzleri by its broader first apical plate that occupies a larger portion of the epitheca. Accordingly, phylogenetic trees from small subunit (SSU) and large subunit (LSU) ribosomal DNA sequences also showed strongly supported separation of the new species from the G. yasumotoi/G. ruetzleri group albeit with short distance. The molecular phylogenies, which included new sequences of the planktonic species Goniodoma polyedricum, further indicated that the globular species of Gambierdiscus formed a tight clade, clearly separated (with strong bootstrap support) from the clade of lenticular species including the type for Gambierdiscus. The morphological and molecular data in concert support the split of Gambierdiscus sensu lato into two genera. Gambierdiscus sensu stricto should be reserved for the species with lenticular shapes, highly compressed anterioposteriorly, with short-shank fishhook apical pore plate, large 2' plate, low and ascending cingular displacement, and pouch-like sulcal morphology. The new genus name Fukuyoa gen. nov. should be applied to the globular species, slightly laterally compressed, with long-shank fishhook apical pore plate, large 1' plate, greater and descending cingular displacement, and not pouch-like vertically-oriented sulcal morphology. Fukuyoa contains the new species Fukuyoa paulensis gen. et sp. nov., and F. yasumotoi comb. nov. and F. ruetzleri comb. nov.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Atlantic Ocean
  • Cell Line, Tumor
  • Dinoflagellida / chemistry
  • Dinoflagellida / classification*
  • Dinoflagellida / genetics
  • Dinoflagellida / growth & development
  • Haplotypes
  • Mice
  • Molecular Sequence Data
  • Phylogeny*

Associated data

  • GENBANK/KM886379

Grant support

This research is supported by the Brazilian Conselho Nacional de Desenvolvimento Científico e Tecnológico (grant numbers BJT 370646/2013-14 to F. G., and 402759/2012-5 and 311936/2013-0 to R. M. L.) and the Natural Science Foundation of China grants (41129001, 41330959 to S. L.), and United States National Science Foundation grant (EF-0629624 to S. L.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of manuscript.