Spirodiscus, Gunton & Kupriyanova & Alvestad & Avery & Blake & Biriukova & Böggemann & Borisova & Budaeva & Burghardt & Capa & Georgieva & Glasby & Hsueh & Hutchings & Jimi & Kongsrud & Langeneck & Meißner & Murray & Nikolic & Paxton & Ramos & Schulze & Sobczyk & Watson & Wiklund & Wilson & Zhadan & Zhang, 2021

Gunton, Laetitia M., Kupriyanova, Elena K., Alvestad, Tom, Avery, Lynda, Blake, James A., Biriukova, Olga, Boeggemann, Markus, Borisova, Polina, Budaeva, Nataliya, Burghardt, Ingo, Capa, Maria, Georgieva, Magdalena N., Glasby, Christopher J., Hsueh, Pan-Wen, Hutchings, Pat, Jimi, Naoto, Kongsrud, Jon A., Langeneck, Joachim, Meissner, Karin, Murray, Anna, Nikolic, Mark, Paxton, Hannelore, Ramos, Dino, Schulze, Anja, Sobczyk, Robert, Watson, Charlotte, Wiklund, Helena, Wilson, Robin S., Zhadan, Anna & Zhang, Jinghuai, 2021, Annelids of the eastern Australian abyss collected by the 2017 RV ' Investigator' voyage, ZooKeys 1020, pp. 1-198 : 1

Spirodiscus sp. nov. Fig. 28I

Diagnosis.

Tube less than 1 cm long, very characteristic, thin tusk-shaped and unattached. Tubes fluted with eight ridges (octagonal in cross-section) anteriorly, but tetragonal in cross-section posteriorly. Pinnulated peduncles, thick relative to normal radioles. Opercula cup-shaped with concave chitinous endplates. Five thoracic chaetigerous segments, including simple collar chaetae. Apomatus chaetae absent. Thoracic uncini saw-to-rasp-shaped with wide pegs divided into two lobes, abdominal uncini rasp-shaped. Abdominal chaetae short, with flat triangular denticulate blade.

Remarks.

The species is morphologically similar to Spirodiscus groenlandicus (McIntosh, 1877) known from the North Atlantic Ocean and Southern Indian Ocean but differs by the tube morphology. Specimens were reasonable common in samples collected by Brenke sledge.

Records.

126 specimens. Suppl. material 1: ops. 66, 79, 98, 103, 110 (AM).

Figures

Figure 28. Serpulidae A Bathyvermilia challengeri, tube only (AM W. 49722) B Bathyvermilia cf. kupriyanovae, tube only (AM W. 49707) C Bathyvermilia sp. nov. 3, specimen in white shiny tube (AM W. 49494) D Hyalopomatus dieteri, tube only (AM W. 49689) E Bathyvermilia sp. nov. 4, specimen in tube with high keel (AM W. 49448) F Hyalopomatus sp. nov. 2, specimen removed from the tube (AM W. 49727) G Hyalopomatus sp. nov. 3, specimen removed from the tube (AM W. 49494) H Protis sp. 3, specimen partly removed tube, with egg sacks (AM W. 49682) I Spirodiscus sp. nov., specimens in tubes (AM W. 49511). Scale bars: 2 mm (A, C); 10 mm (B, E); 1 mm (D, F, H); 0.5 mm (G); 2 mm (I).