2007 GSA Denver Annual Meeting (28–31 October 2007)

Paper No. 14
Presentation Time: 8:00 AM-12:00 PM

MORPHOLOGICAL ABNORMALITIES IN ARCHAIAS ANGULATUS (FORAMINIFERA) FROM THE FLORIDA KEYS (USA): AN INDICATION OF ENVIRONMMENTAL CHANGE?


SOUDER, Heidi Crevison and HALLOCK, Pamela, College of Marine Science, University of South Florida, 140 7th Ave. S, St. Petersburg, FL 33701, hsouder@marine.usf.edu

In May 2004, morphological and surface texture anomalies were observed on living Archaias angulatus individuals collected from the Florida Keys. Six types of test anomalies were documented by SEM analysis: microborings, pitted surfaces, microbial biofilms, calcification (structural) anomalies, dissolution, and deformation. In 2006, a comprehensive study was undertaken to see if the occurrence and types of morphological abnormalities have changed in A. angulatus from the Florida Keys over the past 2.5 decades. Archived samples of A. angulatus collected in 1982-83 from John Pennekamp Coral Reef State Park were compared to recent samples. Thus far 9 different types of morphological abnormalities and 22 combinations of abnormalities have been found in the 2006 samples. Types of morphological abnormalities found in the 2006 samples included profoundly deformed tests, curled, creased, asymmetrical or uncoiled tests, irregular suture lines, and surface texture anomalies. The 1982-83 samples also had morphological abnormalities but it has yet to be determined if the 2006 samples are significantly different form the samples collected in 1982. Additional research will be required to determine experimentally if reduced carbonate saturation can induce such anomalies.