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Lophoconus titanothericeras Clark and Campbell, 1942

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Shell rather large, sooth, cephalis with two forked, very prominent horns, decidedly unequal, the major one much the stronger, subvertical (usually 0.3-0.36 total length), the shorter, minor one at an angle to the longer (32-43°), its length usually about 0.4 length of longer horn, both horns stout (3°), equally four-bladed, the angles decurrent distally, strong basally, slightly twisted, blades arising directly and seperately on the roof of the cephalis; cephalis with asymmetrical, flattened to and sloping sides which expand evenly to the base, its height usually about 0.18 total length, the base commonly as wide as high, sometimes more; thorax widely conical (commonly 35°-55°), with strongly convex sides, occasionally asymmetrical, its length as high as that of the cephalis or somewhat more, and its basal diameter, which is limited by a relatively wide, horizontal septal band, 0.46 total length, the septal band, forming around the outside of the shell an indented ring; abdomen rather variable, its extreme length being 0.4 total length on one hand, and on the other it is reduced to a mere skirt; in more usual individuals it is about 0.3 total length; in shape it may be subcylindrical, barrel-like, or perhaps, more usually, inverted, truncate-conical (27°) with contracted aperture, and asymmetrical, convex sides; aperture the simple shell openig which has a diameter of 0.23-0.34 total length; wall rather thick in the thorax, otherwise thinner; surface of horns, hyaline; of cephalis, more or less smooth, glassy; of thorax, with large, scattered, circular pores which are sunken into concave areas, these areas with knoblike sepaloid points, so that the general thoracic surface is knobby; of abdomen, with about fifty or sixty large, circular pores, these pores nearly twice the diameter of those of the thorax, without sepaloid points so that the general abdominal surface is neatly smooth; rarely a few pores fuse in pairs; margin of abdomen with inconspicious subregular arches or more commonly rough as if torn. Length of shell , 133-250µ; of horns, 26.8-83.5µ; of cephalis and thorax to septal band, 73µ; diameter of abdominal pores, 9µ.
Clark and Campbell 1942











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