Bathyedithia sp.

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

Bathyedithia sp.

Diagnosis.

Specimen small-bodied, short, with 23 segments and 10 pairs of elytrophores. All elytra missing. Prostomium bilobed, median and lateral antennae absent, frontal filaments absent, facial tubercle absent. Jaws with lateral serrations, pharynx not everted, thus number of terminal papillae not observed. Palps with small palpophores, palps of similar length to tentacular cirri. Tentaculophores achaetous. Notopodia shorter than neuropodia, with elongate acicular lobes. Notochaetae slenderer than neurochaetae; notochaetae with subdistal rows of fine spines, neurochaetae flattened to concave, serrated along both margins. Ventral cirri from segment 3 inserted medially on neuropodia. Nephridial papillae not observed. Ventral keel absent posteriorly.

Remarks.

The specimen is damaged and fragile, and most notochaetae and all elytra are missing. Two genera share the characters which distinguish our specimen (10 pairs of elytra, median and lateral antennae absent): Bathyedithia and Polaruschakov . Both genera also have similar neurochaetae, which are flattened and serrated on both margins. Bathyedithia has seven or nine pairs of terminal papillae on the pharynx compared with Polaruschakov which has 14 pairs ( Pettibone 1976) but we have been unable to observe this character on our single fragile and damaged specimen. On the basis of the presence of lateral serrations of the jaws which were observed (and which are absent from Polaruschakov species) we assign this specimen to Bathyedithia .

Records.

1 specimen. Suppl. material 1: op. 31 (AM).