Potamethus malmgreni (Hansen, 1878)

Tovar-Hernandez, Maria Ana & Jirkov, Igor A., 2024, Jasmineira filatovae Levenstein, 1961, the deepest known sabellid is a Potamethus Chamberlin, 1919: redescription, new combination and generic emendation, Zootaxa 5486 (1), pp. 48-70 : 62

Potamethus malmgreni (Hansen, 1878)

Figures 6–7

Potamilla malmgreni Hansen, 1878, p. 13 , pl. IX, figs. 9–13.

Patamilla malmgreni Hansen, 1882, p. 42 –43, pl. VII, figs. 23–27.

Gorbunovia malmgreni Annenkova, 1952: 152–153 , figs. 7–8 fide Hartman, 1965a: 76.

Potamethus malmgreni — Hartman, 1965a: 77.— Knight-Jones, 1983: 271.— Jirkov, 2001, 549, figs. 1–6.— Budaeva et al., 2014: 227.

Material examined

Norwegian Sea and Arctic Ocean ( DGEH and ZIN): samples from several oceanographic cruises ( Table 3 ).

Figures

FIGURE 6. Potamethus malmgreni (Hansen, 1878) from the Norwegian Sea stained with methylene blue, light microscopy images. A) Collar and base of radiolar crown, ventral view, B) same, dorsal view, C) same, ventral view, D) ventral shields and transition of thorax and abdomen, E) ventral shields from posterior abdomen, F) thoracic uncini, arrow points to uncinal hump. Abbreviations: 1, 2) number of chaetigers, apr) anterior peristomial ring, pl) parallel lamella, vsa) ventral shields of abdominal segments, vsc) ventral shield of collar, vst) ventral shield of thoracic segments. Scale bars: A–C, E) 500 µm, D) 1 mm, F) not scaled.

FIGURE 7. Light microscopy images of thoracic and abdominal chaetae of Potamethus malmgreni (Hansen, 1878) from the Norwegian Sea. A) Collar chaetiger, B) close up of collar chaetae, C–E) thoracic uncini and companion chaetae from chaetiger 4, F) thoracic chaetiger 5, G) superior thoracic elongate, narrowly hooded chaetae from chaetiger 5, H) inferior paleate chaetae from chaetiger 5, I) abdominal chaetiger 6, J, K) abdominal uncini from chaetiger 4, L) detail of inferior group of abdominal chaetae from chaetiger 6. Scale bars: A) 100 µm, rest not to scale.