Fabriciidae indet.

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

Fabriciidae indet.

Diagnosis.

One small complete specimen, ~ 2 mm long. Branchial crown with three pairs of radioles with long pinnules terminating at same height as radioles. Eight thoracic and three abdominal chaetigers. Peristomial collar low, membranous, entire ventrally, mid-dorsally incised, anterior margin with shallow lateral notches (ventral conical flap or lobe absent). Dorsal lips as low rounded structures, ventral filamentous appendages absent. Conical structure above mouth absent. Peristomial glandular patches present. All thoracic notochaetae of two lengths: superior elongate, narrowly hooded; inferior short, narrowly hooded. Notochaetae of segments 3-8 similar to those of 1 and 2, pseudospatulate notochaetae absent. Thoracic uncini acicular with few rows of similar-sized teeth above main fang, hood present. Abdominal uncini with rasp-shaped teeth and long manubrium. Pigmented pygidial eyespots absent.

Remarks.

This single specimen has been preserved in 95% ethanol and may have lost pigmentation of the peristomial and pygidial eyes. There are many similarities with the genus Fabriciola but the absence of ventral filamentous appendages is not typical for that genus, so the identification is tentative. More complete and well-preserved specimens would be required to provide a positive identification. This specimen also does not match the diagnosis for Pseudofabriciola , with which it is also similar. This specimen is also similar to that found in the deep GAB surveys of 2015 and 2017, recorded as '? Fabriciola sp.' ( MacIntosh et al. 2018: additional file 2).

Records.

1 specimen. Suppl. material 1: op. 54 (AM).