Gooday, 1981
Diagnosis
Carapace shape typical of the rotundata group (= Claus' genus Metaconchoecia). The dorsal margin more or less straight, ventral margin curves smoothly into the posterior margin (C. discoveryi Habitus 1, C. discoveryi Habitus 3). In ventral view, the rostrum is just visible, but otherwise the appearance is symmetrical (C. discoveryi Habitus 2, C. discoveryi Habitus 4). Sculpturing absent. The right asymmetrical gland opens posterior of the rostrum, left asymmetrical gland opens immediately under the posterior end of the hinge.
Female, frontal organ capitulum slightly differentiated from the stem (C. discoveryi 1). Second antenna endopodite with "a" seta half length of "b", both setae are bare (C. discoveryi 2).
Male, capitulum clearly differentiated (C. discoveryi 3). The first antenna with long "a" seta and minute "c" seta. The "e" seta armature eleven pairs of proximally pointing spines (C. discoveryi 4).
Remarks
Gooday, 1981 recently revised the rotundata group from the Atlantic, the species from other oceans will need a similar revision. C. discoveryi is most similar to C. fowleri (Conchoecia fowleri) but its carapace tapers less anteriorly and the posterior end is more clearly upturned. C. discoveryi is distinguished from all other similar species by the relatively posterior position of the opening of the left asymmetrical gland, and the shortness of the "e" seta of the male first antenna.
Distribution
This species occurs throughout those areas of the North Atlantic which have been sampled recently by R. R. S. Discovery, but it is most abundant at 40°-60°N. Its occurrence in other oceans awaits confirmation. Its full bathymetric range is 600-1500m, but is most abundant at 900-1500m. Mesopelagic/Bathypelagic. Atlantic 0°-60°N. 1, 2, 3 (R.R.S. Discovery Map). At 53°N 20°W males and juveniles were most abundant at 600-800m, whereas females were most abundant at 1000- 1500m.
Type specimens
Holotype, a dissected male specimen. Deposited in the British Museum (Natural History) No. 1979.693. Paratypes, a dissected female No. 1979.694 and 14 females and 13 males No. 1979.785-794.
Type locality
Discovery Station 7711 haul 32: 52°54.7'N, 20°12.6'W, depth 600-700m, 22-23 May 1971, 2249-0049h, RMT 1.