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Lychnocanoma conica (Clark and Campbell, 1942)

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Lynchnocanium (Lynchnocanella) conicum (sic)

Shell broadly conical; apical horn conical, circular in section, probably elongate; cephalis conical with very strongly convex sides, its basal diameter about equal to the altitude, collar distinct, chiefly separated from the thorax by a change in contour rather than by sharp stricture; thorax asymmetrically truncate-conical with strongly convex sides which reach the greatest diameter well below the middle and just above the level of the origin of the feet, thence the sides contracting rapidly to the flattened apertural face; feet, three in number, equal, equidistant, with slightly expanded and reticulated bases (the legs all broken in the writers' specimens); wall thick, dense; surface of horn, hyaline; of cephalis, smooth and hyaline and without pores; of thorax, with strong subhexagonal, concave areas the angles of which hexagons bear stubby, broad, and blunted sepaloid points so that the surface is rough, a subcircular pore in the center of each of the areas, pores uniform, subregularly in more or less vertical rows; framework rather heavy; aperture small, inconspicuous. Length of shell, 160; of horn, 20(broken); of cephalis, 50; breadth of base of cephalis, 49.6 ; of maximum of thorax, 110 ; diameter of pores, 8.8 .
Lychnocanium conicum n.sp. is not so smooth as continuum Ehrenberg (1875) (Barbados), without sharp collar stricture as pyriforme Haeckel (1887) (Barbados and Recent), and also probably with very different feet, not nodose as tribulus Ehrenberg (1875) (Barbados), and not carinate as carinatum Ehrenberg (1875) (Barbados); it is rough unlike bellum n.sp. which accompanies it in this collection.
Clark and Campbell 1942
Similar to Lychnocanoma sp. A, but smaller in size with a larger cephalis in comparison to the thorax, which is more separated. Cephalis with scattered small circular pores, bearing a conical apical horn of approximately the same length as the cephalis. Thorax with hexagonally framed circular to subcircular pores arranged in longitudinal rows. Three short stout three-bladed feet, slightly divergent.

This species can be distinguished from Lychnocanoma sp. A by its smaller size, its larger and more separated cephalis, the longer and pronounced feet, the smoother surfaceof the shell, and the longitudinal rows of pores.
Abelmann 1990











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