Dysponetinae Aguado, Nygren and Rouse 2015

• Main Authors: Watson, Charlotte, Faulwetter, Sarah
• Format: Text
• Language: unknown
• Published: Zenodo 2017
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Phyllodocida; Chrysopetalidae; Arctic; Southern Ocean; Noto; Rouse; Chivers; Darbyshire; Nygren; North East Atlantic
• Online Access: https://dx.doi.org/10.5281/zenodo.5192342; https://zenodo.org/record/5192342

Subfamily DYSPONETINAE Aguado, Nygren and Rouse, 2015 Subfamily diagnosis Very small to small bodied. Prostomium well developed or simple lobe; with lateral and median antennae, ventral palps; eyes present or absent; nuchal structure ciliated dorsolateral patches. Strongly muscularized pharynx with little proboscidial development, terminal proboscidial papillae, pair of stylet jaws; mouth cover absent, buccal cirri may be present. Notochaetal spines; neurochaetae compound, neurochaetal simple spines may be present. Camerate noto- and neurochaetal shafts. Simple body wall musculature. Body ciliation and lateral organs absent. Pygidium rounded with conical projection. Remarks Diagnosis is based on Aguado et al. (2015) with additional information by senior author (CW). Dysponetinae comprise free-living species belonging to Dysponetus Levinsen 1879, a speciose genus exhibiting the most extensive geographical and depth ranges of all taxa within the family Chrysopetalidae. The subfamily also includes Pseudodysponetus Böggemann, 2009, a monotypic deep-water genus (Böggemann 2009, p. 291, figure 27A). Its type material was examined by CW (HZM D.25012). This taxon is very small, possessing aberrant anterior segments and a pair of very small stylets. The tanned, simple elongate jaws with a small mid-way swelling are similar to the simple rod-like pair of stylets, as seen in Dysponetus species. Dysponetus displays alternative morphological states of sensory structures of the anterior end (see below) but lacks complex body wall musculature and ciliated and glandular fields (Tzetlin et al. 2002). Dysponetus macroculatus Dahlgren, 1996 and Dysponetus populonectens Pleijel, Aguado and Rouse, 2012 have been reported as gonochoristic and Dysponetus pygmaeus Levinsen, 1879 as a protrandic hermaphrodite with filiform sperm (Tzetlin et al. 2002). Males of Dysponetus pygmaeus and other particularly small species (e.g. Dysponetus bipapillatus Dahlgren, 1996 and Dysponetus ovalisetosus Darbyshire and Brewin, 2015) exhibit copulatory organs. Epitokous swimming neurochaetae in Dysponetus caecus (Langerhans, 1880) have been reported by Watson et al. (2014) and Dysponetus cf. pygmaeus larvae have been recorded from the plankton (Watson Russell 1987). : Published as part of Watson, Charlotte & Faulwetter, Sarah, 2017, Stylet jaws of Chrysopetalidae (Annelida), pp. 2863-2924 in Journal of Natural History 51 (47 - 48) on page 2894, DOI: 10.1080/00222933.2017.1395919, http://zenodo.org/record/5184119 : {"references": ["Aguado MT, Nygren A, Rouse GW. 2015. Corrigendum. Diagnosis of Dysponetinae (Chrysopetalidae, Annelida). Cladistics. 32: 219 - 220.", "Levinsen GMR. 1879. Om to nye Slaegter af arctiske chaetopode Annelider. [On new genera of arctic Annelida Chaetopoda]. Vidensk Medd Naturhist Foren KjObenhavn. 80: 9 - 18. Danish.", "Boggemann M. 2009. Polychaetes (Annelida) of the abyssal SE Atlantic. Org Divers Evol. 9: 251 - 428.", "Tzetlin A, Dahlgren T, Purschke G. 2002. Ultrastructure of the body wall, body cavity, nephridia and spermatozoa in four species of the Chrysopetalidae (Annelida, ' Polychaeta'). Zool Anz. 241: 37 - 55.", "Dahlgren TG. 1996. Two new species of Dysponetus (Polychaeta: Chrysopetalidae) from Italy and Papua New Guinea. Proc Biol Soc Wash. 109: 575 - 585.", "Pleijel F, Aguado MT, Rouse GW. 2012. New and lesser known species of Chrysopetalidae, Phyllodocidae and Syllidae from Southern California (Phyllodocida, Aciculata, Annelida). Zootaxa. 3506: 1 - 25.", "Darbyshire T, Brewin PE. 2015. Three new species of Dysponetus Levinsen, 1879 (Polychaeta: Chrysopetalidae) from the South Atlantic and Southern Ocean, with a re-description of Dysponetus bulbosus Hartmann-Schroder, 1982. Zootaxa. 4040: 359 - 370.", "Langerhans P. 1880. Die Wurmfauna von Madeira [The worm fauna of Madeira]. Z Wiss Zool. 33: 267 - 316. German.", "Watson C, Chivers A, Narayanaswamy BE, Lamont PA, Turnewitsch R. 2014. Chrysopetalidae (Annelida: Phyllodocida) from the Senghor Seamount, north-east Atlantic: taxa with deep-sea affinities and morphological adaptations. Mem Vict Mus. 71: 311 - 325.", "Watson Russell C. 1987. Chrysopetalidae. In: Bhaud M, Cazaux C, editors. Description and identification of polychaete larvae; their implications in current biological problems. Oceanis. Vol. 13, Paris: Institut Oceanographique. p. 660 - 670."]}