Amythas Benham 1921

• Main Authors: Schiaparelli, Stefano, Jirkov, Igor A.
• Format: Text
• Language: unknown
• Published: Zenodo 2021
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Terebellida; Ampharetidae; Amythas; Antarctic; Southern Ocean; Malmgren; Commonwealth Bay; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.5281/zenodo.4529801; https://zenodo.org/record/4529801

Genus Amythas Benham, 1921 Type species (by monotypy) and type locality Amythas membranifera Benham, 1921. Type locality: Commonwealth Bay (Antarctica), 325 fathoms (594 m). Diagnosis PROSTOMIUM. Prostomium of Ampharete -like, subdivided by a U-shaped groove; median lobe anteriorly rounded; nuchal organs and ridges absent; lower lip not enlarged and longitudinally grooved; nephridial pores/papillae not visible. THORAX. Dorsal ridges absent. NOTOPODIA. Modified notopodia absent. NEUROPODIA. Neuropodia of single type, their uncini generally similar, enlarged neuropodia absent. Remarks Jirkov (2011) proposed the inclusion of Amythas in Neosabellides Hessle, 1917 with certain doubts. However, the new material from Antarctica available for this study clarifies the position of Amythas , which is here considered valid, and its type species redescribed. The status of Neosabellides has been clarified earlier (Jirkov 2018). Amythas has an Ampharete -like prostomium but it differs from all other known genera of Ampharetinae Malmgren, 1866 by the following combination of characters: i) absence of nephridial pores/papillae behind branchiae; ii) middle lobe of prostomium anteriorly rounded; iii) absence of nuchal ridges and any other structures of the prostomium; iv) thoracic and abdominal neuropodia of the same shape; v) absence of modified notopodia; vi) absence of dorsal ridges; vii) absence of enlarged neuropodia; viii) uncini of thoracic and abdominal neuropodia with similar morphology. The genus Amythas also differs from Ampharete Malmgren, 1866 by the absence of a pair of nephridial papillae behind branchiae. In this aspect Amythas is close to Amage , and that is why Amythas septemdecima Schüller & Jirkov, 2013 was initially placed in Amage . Due to the above considerations, Amage septemdecima (Schüller & Jirkov, 2013) is here transferred to the genus Amythas due to the combination of characters such as the shape of prostomium, the absence of nephridial papillae behind the branchiae, the similarity of uncini and neuropodia throughout the body and the absence of any specific characters of thorax. This is in accordance to Reuscher et al. (2015), who disagreed with the fact that A. septemdecima could be settled in Amage . : Published as part of Schiaparelli, Stefano & Jirkov, Igor A., 2021, Contribution to the taxonomic knowledge of Ampharetidae (Annelida) from Antarctica with the description of Amage giacomobovei sp. nov., pp. 125-145 in European Journal of Taxonomy 733 on pages 134-135, DOI: 10.5852/ejt.2021.733.1227, http://zenodo.org/record/4529795 : {"references": ["Benham W. B. 1921. Polychaeta. Australasian Antarctic Expedition 1911 - 1914, Scientific Reports, Series C - Zoology and Botany 6 (3): 1 - 128. Australasian Antarctic Expedition, Sydney. Available from https: // doi. org / 10.5962 / bhl. title. 16201 [accessed 22 Jan. 2021].", "Jirkov I. A. 2011. Discussion of taxonomic characters and classification of Ampharetidae (Polychaeta). Italian Journal of Zoology 78: 78 - 94. https: // doi. org / 10.1080 / 11250003.2011.617216", "Jirkov I. A. 2018. Redescription of Pavelius uschakovi (Annelida: Ampharetidae). Invertebrate Zoology 15 (4): 340 - 347. https: // doi. org / 10.15298 / invertzool. 15.4.03", "Malmgren A. J. 1866. Nordiska Hafs-Annulater. Ofversigt af Koniglich Vetenskapsakademiens Forhandlingar, Stockholm 22 (3): 355 - 410. Available from https: // biodiversitylibrary. org / page / 32339631 [accessed 22 Jan. 2021].", "Schuller M. & Jirkov I. A. 2013. New Ampharetidae (Polychaeta) from the deep Southern Ocean and shallow Patagonian waters. Zootaxa 3692 (1): 204 - 237. https: // doi. org / 10.11646 / zootaxa. 3692.1.11", "Reuscher M. G., Fiege D. & Imajima M. 2015. Ampharetidae (Annelida: Polychaeta) from Japanese waters. Part IV. Miscellaneous genera. Journal of the Marine Biological Association of the United Kingdom 95 (6): 1105 - 1125. https: // doi. org / 10.1017 / S 0025315415000545"]}