Metaconchoecia skogsbergi Iles, 1953
Size
| Southern O. | N | Mean mm | s.d. | Range mm |
♀ |
152 |
1.43 |
0.073 |
1.30-1.68 |
♂ |
63 |
1.40 |
0.070 |
1.32-1.66 |
A-1 |
50 |
1.12 |
0.054 |
1.08-1.26 |
A-2 |
7 |
0.86 |
0.035 |
0.80-0.92 |
A-3 |
||||
| 9969 | n | Mean mm | s.d. | Range mm |
♀ |
157 |
1.40 |
0.030 |
1.34-1.50 |
♂ |
160 |
1.37 |
0.027 |
1.32-1.46 |
A-1 |
157 |
1.09 |
0.034 |
1.00-1.22 |
A-2 |
147 |
0.82 |
0.022 |
0.76-0.88 |
A-3 |
111 |
0.63 |
0.019 |
0.58-0.66 |
Gooday (1981) reported three size groups of specimens consistent with Skogsberg's description in the Southern Ocean. Granata and Caporiacco (1949) placed Muller’s rotundata group in a separate genus, Metaconchoecia, but failed to designate either type specimens, species or localities.
In his description of Conchoecia rotundata, Müller (1890) suggested two forms, one long the other short. Iles (1953) split these forms into separate species C. teretivalvata (short form) and C. skogsbergi (long form), using Skogsberg’s (1920) account of the long form as the definitive description for Conchoecia skogsbergi. Consequently neither type material nor type localities were designated for either species.
Habitat
-
Large specimens of Metaconchoecia frequently occur at deep mesopelagic depths and these have been usually been referred to as M. skogsbergi. The size ranges we give below were for specimens collected at 600-700m in a single horizontal tow at Discovery station 9969 (59°S; 20°W south of the Polar Front), and are typical of the smaller of the size forms. Females of the larger forms can reach 1.8mm. It is predominantly a Southern Hemisphere species, with the majority of the records coming from latitudes <22°S. However, there have been occasional records from deep water in the Northern Hemisphere.
-
Leung reported this species as being caught in samples collected from the Fletcher Ice Island between 54° and 61°N but without giving precise co-ordinates. Similarly Chavtur (1976) reported it from several positions between 46°-55°N in the North Pacific but has since (2003) described these specimens as new species.
-
Angel (1968) reported a single female specimen collected in the Norwegian Sea at 65°N 20°W, which Gooday (1981) re-examined and concluded it was similar to, but not necessarily identical with Southern Ocean specimens. He therefore designated this specimen as C. aff. skogsbergi, and probably this name should be given to all specimens and records from the Northern Hemisphere until they can be critically re-examined.
Created: December 27, 2010
