(Lubbock, 1860)
Description
Small, globular appearance and highly sculptured shell is typical of curta group. Carapace height is two thirds the length [C.curta-fem-lat; C.curta-male-lat]. Male rostrum straight, female rostrum curved. The male carapace tapers anteriorly; development of the shoulder vaults gives biconvex outline to flanks in ventral aspect. Right asymmetrical gland opens at postero- ventral corner; left asymmetrical gland at postero-dorsal corner.
Female, frontal organ undifferentiated, the capitulum a slight terminal swelling extending slightly beyond the end of first antenna [C.curta-1 ]. The first antenna with a dorsal seta; sensory setae bifid [C.curta-1 ].
Male, frontal organ with down-turned capitulum. The first antenna with bifid "a" seta, minute "c." seta, remaining setae subequal [C.curta-3 ]. The armature of the "e" seta is reduced to a single row of 8-13 well spaced pegs [C.curta-4 ]. Right second antenna, the hook appendage of endopodite with spinose recurved tip; "i" seta with spinose base [C.curta-5 ].
Size
Female 0.8-0.9 mm, male 0.75-0.95 mm carapace length.
Depth range
Epipelagic to shallow mesopelagic; females extend down to deep mesopelagic.
Distribution in the North Sea
No information available.
World distribution
All oceans; 60°N-37°S in Atlantic, but seasonal in occurrence at latitudes higher than 40°.
Remarks
According to recent taxonomic revision, the species curta is placed in the genus Mikroconchoecia (M.V. Angel, pers. com.). However, for technical reasons the former generic name Conchoecia had to be maintained in the multimedia files.
Adult C. curta are difficult to distinguish from C. echinulata [Conchoecia echinulata]. C. curta is slightly larger and there are minor differences in the pattern of sculpture. The position of the right asymmetrical gland (which in C. echinulata is a third the way up the posterior margin) is definitive but difficult to see. The armature of the "e" seta has >8 pegs in C. curta [C.curta-4 ]. Copulatory organ normal size (cf. large organ in C. echinulata).
[After Angel, 2000]