Austrolaenilla 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

Austrolaenilla sp. Fig. 22B

Diagnosis.

Two complete specimens (AM W.52215; 1.5 cm long, 0.5 cm wide excluding chaetae; AM W.52016: 7 mm long, 3 mm wide excluding chaetae) with 30-35 segments, 14 or 15 pairs of elytrophores, on 2, 4, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 26, 29, 32, all elytra missing. Dorsum with transverse red-brown pigment on every segment to posterior. Head with small cephalic peaks, two pairs of eyes of similar small size, anterior pair situated mediodorsally and level with widest part of prostomium, posterior pair more dorsal. Median antenna with ceratophores inserted in anteromedial notch, style missing, lateral antennae with ceratophores inserted ventral to prostomial lobes, bases touching, with short papillated styles, less than half length of prostomium. Palps long, with rows of small papillae. Tentaculophores with stout notochaetae present. Dorsal cirri present throughout body; dorsal tubercles low, nodular. Parapodia with notopodia shorter than neuropodia, both with elongate acicular lobes, neuropodial acicular lobe with extended papilla-like process. Notochaetae all stout, thicker than neurochaetae, with rows of spines and blunt tips. Neurochaetae all long, fine capillaries, with rows of long slender spines longer than the width of the neurochaeta, and more distally, long fine hairs terminating in a tuft, some with capillary tips and some with truncate tips. No other types of neurochaetae present.

Remarks.

The small size of the specimens (30-35 segments, ~ 40+ segments for Austrolaenilla species) indicates that they may be juvenile, but the identification is based on the diagnostic feature for the genus: the presence of neurochaetae much slenderer than notochaetae, and with capillary tips that terminate distally in tufts of fine hairs, which these specimens possess. There are ten currently valid Austrolaenilla species ( Read and Fauchald 2020), some of which have been described and reported from southern Antarctic and New Zealand waters, but we are unwilling to attempt a more specific identification due to the small and probably juvenile nature of the specimens.

Records.

2 specimens. Suppl. material 1: ops. 4, 42 (AM).

Figures

Figure 22. Polynoidae A Admetella cf. longipedata anterior end, dorsal view (AM W. 51461) B Austrolaenilla sp. anterior end, dorsal view (AM W. 52215) C Bathyeliasona nigra anterior end, dorsal view (AM W. 52216) D Eunoe cf. abyssorum anterior end, dorsal view (AM W. 51463) E Eunoe cf. opalina dorsal view and elytra (AM W. 51464). Scale bars: 1 mm (A, D, E); 3 mm (B); 2 mm (C).