Spiophanes Grube, 1860
Spiophanes algidus Meißner, 2005
Spiophanes algidus Meißner, 2005
Voucher specimens. Sea Lion: Stations 28 MFC and 32MFC large, adult specimen; Station 20MFB example of juvenile
Diagnosis. Vouchers incomplete specimens with 23-24 chaetigers, 0.8 mm wide and 4.3-6 mm long (adults). Prostomium bell-shaped, with short anterolateral horns in adult; in juveniles prostomial shape more variable anteriorly rounded to triangular with anterolateral horns less to well developed. Occipital antenna present, large, ciriform. Eyes absent. Dorsal ciliated organs present as two mediolateral lines extending to about chaetigers 14-15 (often indistinct). Peristomium poorly to moderately developed.
Chaetigers 14 with long cirriform to triangular notopodial postchaetal lamellae. Chaetal spreader 0+1 type (see Meißner (2005) for definition) with semicircular glandular opening well developed in chaetigers 57. Ventrolateral intersegmental pouches present from between chaetigers 15-16 (in some juveniles the pouches can appear slightly later in between chaetigers 17-18). Dorsal ciliated crests distinct from about chaetigers 17-18, well developed from about chaetiger 20.
Chaetae of 4 types: capillaries (simple and narrowly limbate); single stout, crook-like chaeta in the neuropodium of chaetiger 1; ventral, granulated at tip sabre chaetae from chaetiger 4; 5-6 neuropodial hooks without hoods from chaetiger 15. Pygidium unknown.
Remarks. The specimens collected from Falkland Islands agree well with the description of S. algidus, which also has sub-Antarctic distribution (known from near Crozet Island) in possessing bell-shaped prostomia with an occipital antenna, long dorsal ciliated organs and intersegmental ventrolateral pouches from segment 15 to 16. The Falkland Island specimens differ in the lack of observable pigmentation noted in S. algidus by Meißner (2005). A large number of small specimens has been collected during the 2012 survey. Given the size of these specimens and the fact that these agree well with the description above (see note on the start of pouches above), the conclusion was made that these represent a juvenile stage of S. algidus. Meißner (2005) remarked that S. algidus is most similar to S. kroyeri, whose distribution has been restricted to Northern Europe. Previous faunistic studies recorded S. kroyeri from Falkland Islands (e.g. Blake 1983), but it is likely that these records belong in fact to S. algidus.
Distribution. Southern Ocean (Crozet Island), Falkland Islands.