Orbiniidae (Annelida: Errantia) from Lizard Island, Great Barrier Reef, Australia with notes on orbiniid phylogeny

Abstract

The fauna of Orbiniidae (Annelida: Errantia) from the Lizard Island has been studied. Five species were found and each was redescribed and illustrated using light microscopy and SEM. Scoloplos acutissimus Hartmann-Schröder, 1991 and Scoloplos dayi Hartmann-Schröder, 1980 collected for the first time since their original descriptions and confirmed through re-examination of their type materials. Molecular analyses were carried out using nuclear 18S rDNA and mitochondrial 16S rDNA and CO1 gene sequences with evolutionary distances and the Neighbor-Joining Method. The molecular analyses did not support the monophyly of the genera Scoloplos, Leitoscoloplos, Leodamas, and Naineris, and its results are incongruent with morphological data.

Polychaeta Orbiniidae from Antarctica, the Southern Ocean, the Abyssal Pacific Ocean, and off South America

“…Similar results suggest that common and widely distributed species of orbiniids may consist of suites of morphologically similar sibling species (Bleidorn et al 2006). A more recent molecular phylogeny of orbiniids using a larger suite of species by Zhadan et al (2015) also did not support the monophyly of several well-known genera; their tree topologies, however, differed from the earlier results of Bleidorn et al (2009).…”

“…However, the original account was brief and certain key characters were not clearly discussed or illustrated. The species was subsequently reported from Viet Nam (Gallardo 1967), the Andaman Sea (Eibye-Jacobsen 2002), and Australia (HartmannSchröder 1979 as L. rubra australiensis fide Eibye-Jacobsen 2002) and Zhadan et al (2015). The two latter accounts reported considerable variability in the size, shape, and degree of curvature of the abdominal neuropodial uncini.…”

A new species of polychaete worm from Juan Fernandez Archipelago, Chile, Scoloplos juanfernandezensis n. sp. (Polychaeta: Orbiniidae)

“…Branchiae simple or branched, from chaetiger 8 or later. 1-2 thoracic neuropodial podial papillae, 0-2 thoracic subpodial papillae, 0-4 abdominal subpodial papillae, stomach papillae absent (Zhadan et al, 2015). Scoloplos juanfernandezensis n. sp.…”

“…The peristomium consists of one or two achaetous rings (Blake, 1996;Glasby, 2000;Solís-Weiss et al, 2009). Worldwide, the Orbiniidae consist of 17 genera and about 150 species (Zhadan et al, 2015).…”

“…Recent studies by Blake (2000), Kruse et al (2004), Bleidorn (2005), Bleidorn et al (2009), Dean & Blake (2015), and Zhadan et al (2015) have helped to clarify some questions about the family Orbiniidae and the ge-nus Scoloplos. Blake (2000), Bleidorn (2005), Bleidorn et al (2009) and Dean & Blake (2015) have considered the subgenera Scoloplos and Leodamas as separate genera because they are not closely related and do not constitute sister groups.…”