Chaetocirratulus Blake 2018
Genus Chaetocirratulus Blake, 2018 Type species: Heterocirrus andersenensis Augener, 1932. Original designation by Blake 2018. Diagnosis. (after Blake 2018) Prostomium broadly rounded anteriorly or wedge-shaped; eyespots absent; with a pair of small nuchal organs as slits or depressions at posterior...
| Main Author: | |
|---|---|
| Format: | Other/Unknown Material |
| Language: | unknown |
| Published: |
2022
|
| Subjects: | |
| Online Access: | https://zenodo.org/record/6958000 https://doi.org/10.5281/zenodo.6958000 |
| Summary: | Genus Chaetocirratulus Blake, 2018 Type species: Heterocirrus andersenensis Augener, 1932. Original designation by Blake 2018. Diagnosis. (after Blake 2018) Prostomium broadly rounded anteriorly or wedge-shaped; eyespots absent; with a pair of small nuchal organs as slits or depressions at posterior edge. Peristomium with a single pair of grooved dorsal tentacles arising from posterior margin or interface with setiger 1. First pair of branchiae arising from posterior margin of peristomium, an achaetous segment, or setiger 1. Body typically thick and fusiform over many segments, rarely with middle or posterior body segments beaded or moniliform; individual segments short, numerous. Setae include capillaries on most setigers and thick, pointed acicular spines in neuropodia and a few in notopodia or spines in neuropodia only; spines few, often small and inconspicuous, not forming cinctures. Individual spines straight to weakly sigmoid. Pygidium a simple ventral lobe. Remarks. Species of Chaetocirratulus include a heterogeneous group of cirratulids that share characteristics of both the multitentaculate genus Cirratulus Lamarck, 1818 and the bitentaculate genus Chaetozone. The genus was established by Blake (2018) to accommodate a group of Chaetozone species that had large, often fusiform bodies with only a few acicular spines that were not arranged in spreading fascicles or in the more typical cinctures. Petersen (1991) had earlier recognized that these species did not agree with Chaetozone and referred them to the multitentaculate genus Cirratulus and redefined the genus to include species having two tentacular cirri in addition to multiple pairs of tentacles. Two species previously described from the western North Atlantic Ocean considered to possibly belong to Chaetocirratulus are Chaetozone benthaliana McIntosh, 1885 from off Nova Scotia in 2275 m and Chaetozone gayheadia Hartman, 1961 from off New England in 300 m. Comments on Chaetozone benthaliana . Chaetozone benthaliana is an enigma because the holotype ... |
|---|