Oweniidae Rioja, 1917
Galathowenia Kirkegaard, 1959
Galathowenia sp. 1
Voucher specimens. SEA LION: station 6MFB, 9MFB and 51MFB.
Diagnosis. Few large and robust and several small and slender specimens were collected, which are here considered as adult and juvenile examples of the same species; all in tough (hard to open) tubes composed of particles and internally lined with membrane. Voucher is a relatively large, robust specimen 17mm long, about 0.8mm wide, posteriorly incomplete. Prostomium collar-like, short (similar in length to chaetiger 1); no eyes. Thorax composed of 3 uniramous chaetigers of varying length: 1st short, 2nd longer (1.5 – 2x the length of 1st chaetiger), 3rd short again. Abdominal segments very long (till end of body, which is an incomplete fragment). Notochaetae long, coarsely serrated capillaries; neuropodial hooks from chaetiger 4, arranged in many (about 20) alternating rows in anterior abdomen and in about 13 irregular rows in posterior abdomen. Form of uncini similar in anterior and posterior abdomen, all bidentate, with equally sized, slender, widely separated teeth arranged dorsally and ventrally; manubrium straight (slightly larger just below the teeth, but not forming subdistal knob). Pygidium uknown.
Remarks. Galathowenia scotiae (Hartman, 1978) – described with prostomium missing by Hartman (1978) who reported there are only 2 instead of 3 thoracic (uniramous) chaetigers. Based on Hartman’s drawing the chaetiger 2 (which she considered chaetiger 1) is about the same length as the following chaetiger, however in key provided by De León-González & Sanchez-Hernández, 2012 and in Capa et al. 2012 G. scotiae is cited as having 2nd thoracic segment twice the length of the 1st and 3rd, which corresponds well with FI specimen. However G. scotiae differs from Falkland Islands’ specimens in that the manubrium of uncini has an abvious enlarged subdistal knob and two unicnal teeth appear to be close together. Importantly, there is a “groove” present between 1st and 2nd chaetigers in G. scotiae and this feature was not unambiguously confirmed in Falkland Islands’ specimens. Parapar (2003) suggested: “There is a need for a revision of the genus Galathowenia, and particularly of the sibling species characterized by the absence of eyes, the presence of a thoracic slit between the first and second setigers, and a similar head and hook shape”. The most similar species outside the geographical area is G. piltzi described by Blake (2000) from 92m, off California, which possesses similar types of hooks and sparse serration on notochaetae as seen in Falkland Islands specimens, but the 3 thoracic segments are all of the same length. With current evidence we assign Falkland Islands specimens to Galathowenia sp. 1.
Other Galtahowenia species known from the region, differ in following (main) characters:
G. longicollaris (Hartmann-Schröder & Rosenfeldt, 1989) – with 3 thoracic chaetigers, its prostomium is much (about 4x) longer than the first segment.
G. joinvillensis (Hartmann-Schröder & Rosenfeldt, 1989) – with only 2 thoracic chaetigers.
G. antarctica Cantone & Di Pietro 2001 – with 2 short thoracic chaetigers.
