Lacydonia cf. laureci Laubier, 1975

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

Lacydonia cf. laureci Laubier, 1975

Diagnosis.

Specimen incomplete, ~ 2 mm wide excluding chaetae, 3 mm long for head plus 12 anterior segments. Body dorsoventrally flattened. Prostomium approximately as wide as long, somewhat indented anteriorly, with conspicuous lateral lobes present on posterior margin of prostomium, giving the appearance of a much wider than long prostomium. Eyes absent, median antenna missing. Pair of short digitiform to filiform lateral antennae located in slight incisions mid-prostomium; pair of similar-sized/shaped palps arising ventral to prostomial anterior margin. Faded pale brown pigment present on prostomium, dorsally and ventrally, and dorsally as transverse bands on tentacular segment and some other segments, and as spots on dorsal cirri and parapodia. Tentacular segment short, achaetous, with pair of ventrolateral cirri. Chaetigers 1-3 uniramous, with compound spinigerous chaetae, subsequent parapodia biramous, rami elongate and widely separated, with elongate supracicular lobes. Notochaetae simple capillary chaetae, finely spinulose distally; neurochaetae compound spinigers with heterogomph shaft-heads and long, finely spinulose blades. Dorsal cirri short, thick, digitiform, glandular, inserted basally on first three chaetigers, thereafter medially to distally on notopodia. Ventral cirri of similar size and shape, inserted distally on neuropodia. Posterior segments, pygidium and pygidial cirri, all missing and therefore unknown.

Remarks.

Lacydonia laureci Laubier, 1975 is the only currently described species that possesses conspicuous lateral lobes on the posterior margin of the prostomium. This specimen bears some similarity to L. laureci , because of these lobes, as well as the absence of eyes, but there are a few differences also apparent: Rizzo et al. (2016) report that L. laureci possesses capillary notochaetae that have coarse serrations on the distal part of the chaetae, but Böggemann (2009), however, describes fine serrations over the entire length of the notochaetae for that species, whereas this specimen from Australian waters appears to possess fine serrations only on the distal portion of the notochaetae. L. laureci has also been reported from several widely distributed locations in 1001-5497 m depths: the type locality, Matapan Trench, Mediterranean Sea ( Laubier 1975); Angola, Cape and Guinea Basin, SE Atlantic Ocean ( Böggemann 2009), and the Campos Basin off Brazil, South Atlantic Ocean ( Rizzo et al. 2016). Because this specimen consists of an anterior end only, this can only be a tentative identification.

Records.

1 specimen (incomplete). Suppl. material 1: op. 110 (AM).