Conchoecia loricata

Claus, 1894

Diagnosis
Carapace strongly tapers anteriorly. Maximum height of about 50% length, at about five sixths of the length (C. loricata Habitus 1, C. loricata Habitus 3). Shoulder vaults clearly visible in profile. The postero-dorsal corner right-angled. Sculpture, longitudinal striae on dorsal region of the rostra, and oblique striae across antero-ventral region below incisure intercepting ventral margin at about 45°. Left asymmetrical gland opening at the postero-dorsal corner; right asymmetrical gland opening at the postero-ventral corner with a supplementary group of cells opening immediately alongside.
Female, frontal organ well differentiated, capitulum slightly down-turned, finely spinose along most of ventral margin, but only a third of dorsal margin (C. loricata 1). Dorsal margin of capitulum concave, produced into a terminal rounded process, giving a characteristic outline. First antenna with clear segmentation, a long dorsal seta present, "a"-"d" setae are about half the length of the "e" seta.
Male, frontal organ, capitulum down-turned, dorsal surface concave, ventral margin finely spinose on basal half to two-thirds (C. loricata 3). First antenna with short, U-shaped "a" seta, "e" seta armature a double row of about 22 short spines slightly off-set, proximally decreasing in size (C. loricata 4). Second antenna endopodite, "b" seta with patch of long hairs at midlength (C. loricata 5), sensory seta ("h", "i", and "j") a third the length of the "f" seta.

Remarks
This species is similar to C. ctenophora (Conchoecia ctenophora) from which it is most readily distinguished on the basis of size. Poulsen, 1973 separated these species under his new genus Loricoecia and Chavtur, 1977 included his new species L. acutimarginata (Conchoecia acutimarginata). Müller, 1906 reported a smaller form of C. loricata (Conchoecia loricata) from the tropical Atlantic and Indian Oceans (females 1.6-1.7mm, males 1.55mm), which may turn out to be another sibling species.

Distribution
Reported from all oceans, 60°N-37°S in Atlantic. Common mesopelagic species in the North Atlantic at depths of 500-900m. 1, 2, 3 (R.R.S. Discovery Map).

Type specimens
None designated; status of original material uncertain.

Type locality
Original description based on material from two stations in the North Atlantic at 33°N 20°52'W and 32°35'N 19°48'W.

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