TAPHONOMIC ANALYSIS OF FUSULINID EPIBIONTS (TOLYPAMMINA AND SERPULOPSIS) AND ITS IMPLICATIONS FOR THE PALEOECOLOGY OF THE UPPER PENNSYLVANIAN (HUGHES CREEK SHALE, EAST-CENTRAL KANSAS)

Extremely well preserved specimens of Triticites ventricosus occur in the Hughes Creek Shale Member of the Foraker Limestone. Examination of 900 specimens of T. ventricosus from a single locality shows that the 63% of the specimens have epibionts. The major encruster is the agglutinated foraminifer, Tolypammina (Ammodiscidae) while the minor encruster is Serpulopsis insita (Serpulimorpha). Serpulopsis insita does not reveal a preferred orientation on the test but does seem to be more abundant on fusulinids that have experienced either lengthier seafloor exposure times or higher energy levels.

This analysis focuses on Tolypammina's presence on fusulinid tests that have not been obscured by damage (e.g., physical breakage, corrasion, and diagenesis). Recorded for 250 fusulinids was the position of the Tolypammina on the last volution of the fusulinid. Positions were categorized into 1) sagittal sections for left, central, or right comparisons of the fusiform test and 2) transverse quarters of the last test volution. The sagittal analysis of the epibionts reveals the largest number of encrusters (59%) is on the largest substrate, the central section. The remainder of the encrusters are evenly distributed on the poles with 20.7% on the left and 20.3% on the right. The transverse quarters of the fusulinid test show that Tolypammina does reveal a strong preference for encrusting on two of the four quarters. The two quarters comprising the last half of the final volution possessed 67.3% of the Tolypammina.

Results indicate that upon death these fusulinids were gently rolling in this low energy, clay-rich environment. The best preserved specimens were buried immediately or experienced minimal seafloor exposure. However, the majority of the fusulinids were gently rolling and then temporarily settling in preferred orientations making Tolypammina twice as likely to colonize on one side. The preferred orientation was caused by the antetheca bearing side of the test catching on the seafloor to stop the rolling, similar to a gastropod aperture catching. This process would have happened repeatedly until final burial.