New species of Chaetozone and Tharyx (Polychaeta: Cirratulidae) from the Alaskan and Canadian Arctic and the Northeastern Pacific, including <br />a description of the lectotype of Chaetozone setosa Malmgren from Spitsbergen in the Norwegian Arctic

Abstract

Eight new species of cirratulid polychaetes of the genus Chaetozone from the Alaskan (Beaufort Sea) and Canadian Arctic (Baffin Island, Baffin Bay, Labrador, Hudson Strait, and Hudson Bay) and the Northeastern Pacific are reported together with two new species of Tharyx from the Alaskan Beaufort Sea and the Strait of Juan de Fuca. The new species of Chaetozone and Tharyx are compared with related species; distinct species groups within these genera are discussed. A redescription of C. setosa Malmgren, 1867, the type species of the genus from Spitsbergen, based on a lectotype and associated paralectotypes designated by the late Dr. Mary E. Petersen is presented. A review of characters important in the taxonomy of the genera Chaetozone and Tharyx is presented. A key to species of Chaetozone from the Northeastern Pacific and North American Arctic is provided.

Kirkegaardia (Polychaeta, Cirratulidae), new name for Monticellina Laubier, preoccupied in the Rhabdocoela, together with new records and descriptions of eight previously known and sixteen new species from the Atlantic, Pacific, and Southern Oceans

“…sp., also occurs in related bi-tentaculate species of Chaetozone. However, Chaetozone species also have these spines and capillaries in the notopodia which together with the neuropodial spines form posterior cinctures with a distinct armature (Blake 2015). Heavy spines are absent in notopodia of K. araiotrachela n. sp.…”

A new species of Chaetozone (Polychaeta, Cirratulidae) from the Bay of Biscay offshore France, together with a review of Chaetozone species from the North Atlantic and adjacent waters

“…Blake 2015). Prostomium blunt to conical, usually lacking eyespots, with a pair of small nuchal slits or depressions at posterior edge; with a single pair of grooved dorsal tentacles arising from posterior edge of peristomium, or sometimes more posterior on an achaetous anterior segment, or rarely an anterior setiger.…”

“…New investigations have demonstrated that the majority of these records are actually distinct species (see Blake 1996;2006, 2015Chambers 2000;Doner & Blake 2006), with C. setosa itself limited to arctic and subarctic sites in the eastern North Atlantic (Chambers 2000;Blake 2015).…”

“…Due to the increasing number of species of Chaetozone being described, Blake (2015) listed a series of characters important for their identification and suggested that these could also be used to separate certain species into groups. The new species from the Bay of Biscay has several identifying characters including the presence of a distinct dorsal crest on the peristomium, a separate achaetous segment with branchiae anterior to the first setiger, a swollen fusiform-shaped anterior body region, and numerous subdermal glands that produce an elaborate and complex Methyl Green staining pattern.…”

“…Chaetozone bathyala, C. careyi Blake, 2015, C. malmgreni Blake, 2015, C. palaea Blake, 2006, C. pigmentata Blake, 2015, and C. pugettensis Blake, 2015. Blake (2015 provided comparative details of these species; none of these species has a large swollen anterior region similar to that of C. elakata n. sp.…”