Panthalis 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

Panthalis sp. Fig. 2A

Diagnosis.

One damaged specimen, with 24 anterior segments measuring 1.2 cm long, 0.6 mm wide. Head region badly damaged, but some features recognisable: low rounded ommatophores without necks and colourless, a single long median antenna attached mid-prostomium, longer than prostomium length; lateral antennae and palps missing, however; tentaculophores with a few chaetae, styles missing; elytra present on segments 2, 4, 5, 7 and alternating segments thereafter, delicate, transparent. All chaetae simple. Acicular neurochaetae starting from chaetiger 3, notochaetae absent from chaetiger 4 and on all parapodia thereafter. Notopodia with notoaciculum and spinning glands internally, golden ‘spinning’ fibres emergent from the inner surface of the notopodial bract. Superior group of neurochaetae from chaetiger 9 onwards, of two types: long, with plumose (brush) tips, and shorter chaetae with few whorls of short widely spaced hairs along shafts; middle group of neurochaetae stout, acicular chaetae with hairy aristate tips; inferior group of neurochaetae curved, lanceolate, with many transverse rows of overlapping spines along shaft.

Remarks.

This specimen possesses brush-tipped neurochaetae typical of the genera Acoetes and Panthalis , but lacks notochaetae in all middle segments, a feature which distinguishes it as a species of Panthalis . The genus Panthalis has not yet been reported from Australian waters; however, specimens have been collected previously from deep water in the Arafura Sea off Western Australia and Northern Territory ( Murray and Hutchings in prep.).

Records.

1 specimen. Suppl. material 1: op. 104 (AM).

Figures

Figure 2. Acoetidae, Chrysopetalidae, Nephtyidae, Oweniidae A Acoetidae, Panthalis sp., dorsal view (AM W. 50321) B Chrysopetalidae, Dysponetus cf. caecus, dorsal view C Dysponetus cf. caecus, ventral view D Nephtyidae, Aglaophamus sp. pre- and post-acicular chaetae E Nephtyidae, Nephtys cf. paradoxa (AM W. 52750) F Nephtyidae, Aglaophamus sp. G Oweniidae, Myriowenia sp. in tube (AM W. 51842). Scale bars: 2 mm (A); 1 mm (B, C); 50 µm (D); 5 mm (E, G); 3 mm (F).