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Lamprocyrtis heteroporos (Hays, 1965)

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Lamprocyclas heteroporos
Shell rough, campanulate, with indistinct collar stricture but distinct lumbar stricture; relative length of three joints 2.5:5:7, although in some specimens the thorax and abdomen are nearly equal. Cephalis hemispherical, pores, circular to subcircular with diameter about equal to bar width. Cephalis bears a long three-bladed apical horn, as long as, to three times as long as, cephalis. Thorax campanulate, with pores similar in size and shape to those of cephalis, arranged in irregular longitudinal rows, 5-7 pores per row; pores increase in size distally. Abdomen cylindrical to slightly conical with maximum diameter just above mouth; pores large, irregular in size and shape, separated by thick bars; abdominal pores 2-3 times the size of thoracic pores. Aperture slightly constricted, 3-5 poorly developed short terminal teeth extend downward from a thick peristomal ring: Length of apical horn 22-60, of cephalis 15-25, of thorax 48-65, of abdomen 55-70. Maximum width of shell 88-100, diameter of thoracic pores 4-9, usually about 6, of abdominal pores 10-22.
L.heteroporos is easily distinguished from other members of the genus by its cylindrical abdomen and the contrast between the large pores of the abdomen and the smaller pores of the thorax.
Distribution: Lamprocyrtis heteroporos is restricted to zone ϕ in the area of this study and occurs only in three cores, V-16-66, V-17-88 and V-18-69, all of which were taken north of the Polar Front. Its absence from the rich red clay assemblage of V-16-66 and V-17-88 suggest that it was a warm-water species, not tolerant of the colder waters that lay to the south. Its range is shown in Figures 27, 31 and 33.
Hays 1965











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