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Cycladophora conica Lombari and Lazarus, 1988

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Cephalis is simple, of medium size, subspherical with numerous subcircular pores and two apical horns. Horns are bladed and one may possess thorns. They are 1-1.5 times the diameter of the cephalis in length. Cephalis is slightly depressed into the upper thorax, creating a weak spinal furrow. Lateral spines are rarely expressed externally. Upper thorax is compressed, weakly flared, and fairly flat in outline with subcircular to irregularly shaped pores. Pores are small, though non-uniform in size and irregularly arranged. In some specimens the last 1-2 rows of upper thorax pores are arranged in horizontal rows. There may be a gradual, weak pore size gradient increasing distally. Pores are open with pore bars of moderate width and thickness devoid of ornamentation. Lower thorax suture is unconstricted. However, in some specimens a slight constriction appears on one side. Lower thorax is elongate, weakly to moderately flared, and fairly flat in outline. Pores are hexagonal in shape, medium to large in size, and arranged in staggered horizontal rows. A gradual, strong pore size gradient increases distally. Pores are open with narrow pore bars of moderate thickness. Pore bars are free of spines, costae and sponge. Lower thoracic suture is unconstricted. Abdomen is rarely present as 1-2 rows of large, open, hexagonally framed pores. There may be one row of short basal spines and the basal opening is partially closed by a plate consisting of 1-2 rows of pores. These pores are of irregular shape and size.
Lombari and Lazarus 1988


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