Skip to main content
Journal cover image

The phylogeny of extant starfish (Asteroidea: Echinodermata) including Xyloplax, based on comparative transcriptomics.

Publication ,  Journal Article
Linchangco, GV; Foltz, DW; Reid, R; Williams, J; Nodzak, C; Kerr, AM; Miller, AK; Hunter, R; Wilson, NG; Nielsen, WJ; Mah, CL; Rouse, GW ...
Published in: Molecular phylogenetics and evolution
October 2017

Multi-locus phylogenetic studies of echinoderms based on Sanger and RNA-seq technologies and the fossil record have provided evidence for the Asterozoa-Echinozoa hypothesis. This hypothesis posits a sister relationship between asterozoan classes (Asteroidea and Ophiuroidea) and a similar relationship between echinozoan classes (Echinoidea and Holothuroidea). Despite this consensus around Asterozoa-Echinozoa, phylogenetic relationships within the class Asteroidea (sea stars or starfish) have been controversial for over a century. Open questions include relationships within asteroids and the status of the enigmatic taxon Xyloplax. Xyloplax is thought by some to represent a newly discovered sixth class of echinoderms - and by others to be an asteroid. To address these questions, we applied a novel workflow to a large RNA-seq dataset that encompassed a broad taxonomic and genomic sample. This study included 15 species sampled from all extant orders and 13 families, plus four ophiuroid species as an outgroup. To expand the taxonomic coverage, the study also incorporated five previously published transcriptomes and one previously published expressed sequence tags (EST) dataset. We developed and applied methods that used a range of alignment parameters with increasing permissiveness in terms of gap characters present within an alignment. This procedure facilitated the selection of phylogenomic data subsets from large amounts of transcriptome data. The results included 19 nested data subsets that ranged from 37 to 4,281loci. Tree searches on all data subsets reconstructed Xyloplax as a velatid asteroid rather than a new class. This result implies that asteroid morphology remains labile well beyond the establishment of the body plan of the group. In the phylogenetic tree with the highest average asteroid nodal support several monophyletic groups were recovered. In this tree, Forcipulatida and Velatida are monophyletic and form a clade that includes Brisingida as sister to Forcipulatida. Xyloplax is consistently recovered as sister to Pteraster. Paxillosida and Spinulosida are each monophyletic, with Notomyotida as sister to the Paxillosida. Valvatida is recovered as paraphyletic. The results from other data subsets are largely consistent with these results. Our results support the hypothesis that the earliest divergence event among extant asteroids separated Velatida and Forcipulatacea from Valvatacea and Spinulosida.

Duke Scholars

Altmetric Attention Stats
Dimensions Citation Stats

Published In

Molecular phylogenetics and evolution

DOI

EISSN

1095-9513

ISSN

1055-7903

Publication Date

October 2017

Volume

115

Start / End Page

161 / 170

Related Subject Headings

  • Transcriptome
  • Starfish
  • Sequence Analysis, RNA
  • Sequence Alignment
  • RNA
  • Phylogeny
  • Expressed Sequence Tags
  • Evolutionary Biology
  • Animals
  • 3109 Zoology
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Linchangco, G. V., Foltz, D. W., Reid, R., Williams, J., Nodzak, C., Kerr, A. M., … Janies, D. A. (2017). The phylogeny of extant starfish (Asteroidea: Echinodermata) including Xyloplax, based on comparative transcriptomics. Molecular Phylogenetics and Evolution, 115, 161–170. https://doi.org/10.1016/j.ympev.2017.07.022
Linchangco, Gregorio V., David W. Foltz, Rob Reid, John Williams, Conor Nodzak, Alexander M. Kerr, Allison K. Miller, et al. “The phylogeny of extant starfish (Asteroidea: Echinodermata) including Xyloplax, based on comparative transcriptomics.Molecular Phylogenetics and Evolution 115 (October 2017): 161–70. https://doi.org/10.1016/j.ympev.2017.07.022.
Linchangco GV, Foltz DW, Reid R, Williams J, Nodzak C, Kerr AM, et al. The phylogeny of extant starfish (Asteroidea: Echinodermata) including Xyloplax, based on comparative transcriptomics. Molecular phylogenetics and evolution. 2017 Oct;115:161–70.
Linchangco, Gregorio V., et al. “The phylogeny of extant starfish (Asteroidea: Echinodermata) including Xyloplax, based on comparative transcriptomics.Molecular Phylogenetics and Evolution, vol. 115, Oct. 2017, pp. 161–70. Epmc, doi:10.1016/j.ympev.2017.07.022.
Linchangco GV, Foltz DW, Reid R, Williams J, Nodzak C, Kerr AM, Miller AK, Hunter R, Wilson NG, Nielsen WJ, Mah CL, Rouse GW, Wray GA, Janies DA. The phylogeny of extant starfish (Asteroidea: Echinodermata) including Xyloplax, based on comparative transcriptomics. Molecular phylogenetics and evolution. 2017 Oct;115:161–170.
Journal cover image

Published In

Molecular phylogenetics and evolution

DOI

EISSN

1095-9513

ISSN

1055-7903

Publication Date

October 2017

Volume

115

Start / End Page

161 / 170

Related Subject Headings

  • Transcriptome
  • Starfish
  • Sequence Analysis, RNA
  • Sequence Alignment
  • RNA
  • Phylogeny
  • Expressed Sequence Tags
  • Evolutionary Biology
  • Animals
  • 3109 Zoology