Gyrophyllites kwassicensis Glocker, 1841

Diagnosis.—Horizontal, straight to club-shaped lobes radiating from single point; may have burrow fills of different color from host lithology, thin ring of disturbed sediment surrounding radiat ing lobes, and/or lobes that appear bifurcated.

Description: Vertical or oblique shaft from which 10 to several tens of straight, closely spaced tunnels radiate in whorled or stacked arrangement; rosettes up to 9 cm in diameter preserved in epirelief or full relief; central shaft has an incomplete
depth of 5 cm, possibly only representing a small part of its original extent; shaft diameter is 10-14 mm and internally the mica
grains show a preferred orientation parallel to the wall; from the shaft the radial burrows emerge very closely in a constricted interval, less than 4cm thick, often cutting one another; tunnels are 6-15 mm in width, may expand distally and comprise
an active fill; tunnels are lined with micaceous muds; mica-flakes stand more of less parallel to the burrow axis; in the distal end the lining closes the tunnel; fill is normally structureless, but in a few cases in which meniscus structures are distinguished, concave towards the central
tube.