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...Barman, Georgia College State University, Milledgeville, GA 31061. The adult size of Nearctic Dytiscidae is highly variable with lengths ranging from about 1.0 to 34 mm. The objective of this study is the examination of the distribution of adult size within the context of a recent phylogenetic hypothesis. Minimum and maximum body length data for 188 species of North American Dytiscidae (representing 23 genera, 11 tribes, and 5 sub-families) were gathered from the literature. Hierarchical cluster analyses of length data were then used to group sub-families and tribes and results from these groupings were used to construct dendrograms, using average linkage between groups. Relationships between and among the various taxa based on cluster analyses of length were then compared to those indicated by recent phylogenetic studies based on other morphometric characters, including morphology of the dytiscid female reproductive systems. Preliminary results of an analysis of the distribution of adult size among the clades within Dytiscidae indicate two major size-related lineages. A major clade that includes the Hydroporinae appears to be characterized by a progressive reduction in size. Larger beetles (Dytiscinae) are restricted to the second lineage. This project was supported in part by a Faculty Research Grant, Office of Research Services, GC & SU. Aquatic Coleoptera Laboratory Contribution No. 64.
9:15 THE MORPHOLOGY OF THE MATURE LARVA OF HYDATICUS BIMARGINATUS (Say) (COLEOPTERA: DYTISCIDAE: DYTISCINAE), Reginald Jackson * (1), E. H. Barman (1), and B. P. White (2), (1) Georgia College & State University, Milledgeville, GA 31061 and (2) Georgia Military College, Warner Robins, GA 31093. The cosmopolitan genus Hydaticus is represented in Georgia by two species, H. bimarginatus and H. cinctipennis. Mature larvae collected from lower Piedmont and upper Coastal Plain ephemeral habitats were identifiable as Hydaticus by the presence of a broadly rounded nasale, lobes on the labium between the palps, and swimming hairs on the seventh and eighth abdominal segments. The tentative identification of these larvae as H. bimarginatus was based on the relationship between adult total body length and larval cranial length. The cervical region of the cranium has lateral as well as dorsal and ventral notches. Swimming hairs are present on coxae, trochanters, femora, tibiae, and tarsi. The number and distribution of non-natatory sensilla on legs are consistent with those of the family and subfamily. This project was supported in part by a Faculty Research Grant, Office of Research Services, GC & SU. Aquatic Coleoptera Laboratory Contribution No. 63.
9:30 THE IMPACTS OF WHITE-TAILED DEER HERBIVORY AND LONICERA JAPONICA ON THE POPULATION DYNAMICS OF THE ENDANGERED TRILLIUM RELIQUUM, Jacob S. Thompson * and L.M. Leege, Georgia Southern University, Statesboro, GA 30458. Trillium reliquum is a federally endangered herb restricted to 21 populations in Alabama, Georgia, and South Carolina. It is threatened throughout its range by white-tailed deer herbivory and invasive Lonicera japonica, both known to reduce plant fitness. In spring 2005, five populations were chosen to determine the effects of white-tailed deer herbivory and L. japonica across the range of T. reliquum. Four treatments were established within each population, including: 1) deer excluded, honeysuckle present 2) deer excluded, honeysuckle removed 3) deer accessible, honeysuckle present (control), and 4) deer accessible, honeysuckle removed. Trillium reliquum was censused within each treatment. The density of T. reliquum ranged from 0.6 to 9.3 individuals/[m.sup.2]. Non-reproductive sub-adult stages comprised 52 [+ or -] 8% of the population while seedlings made up only 5 [+ or -] 1%. Only 26% of flowering plants set seed. In spring 2005, deer herbivory ranged from 1 to 10% across populations. With low reproductive rates, poor recruitment, increasing deer herbivory, and the presence of L. japonica, the already globally small populations of this rare species may be vulnerable to decline.
9:45 A SURVEY AND ANALYSIS OF FISH DIVERSITY IN THE ALAPAHOOCHEE RIVER OF SOUTH GEORGIA, David L. Bechler, Department of Biology, Valdosta State University, Valdosta, GA 31698-0015. A survey of the fish fauna of the Alapahoochee River basin was conducted from August 2004-December 2005. The Alapahoochee River, a blackwater system, is formed by the confluences of Knights, Mud and Grand Bay creeks. The majority of the drainage basin lies in flatwoods habitat with low stream gradients except in the Alapahoochee River where stream gradient increases markedly as it flows through Tertiary limestone. The 27 sampling sites produced 39 species in 14 families. Centrarchidae was the most speciose with 13 species, five families were represented by only one species and the remaining families were represented by two to four species. Species diversity was examined using a between sample similarity index [SI = 2C/(A+B)]. SI values between sites showed no specific pattern over the course of any creek or the Alapahoochee River. Some of the lowest SI indexes and species diversities were found on the Alaphoochee River where it passes through limestone beds providing minimal habitat. Habitat structure at individual collecting sites combined with anthropogenic activities such as channeling of stream beds and bridge building are seen as major factors influencing fish diversity.
10:00 Section Business Meeting
10:30 POSTER SESSION in B atrium
POSTERS
B-Atrium
ONGOING BIOMECHANICAL ANALYSIS OF MANDIBULAR VARIATION IN SELECTED DYTISCIDAE (COLEOPTERA) LARVAE, Christy C. Cecil *, W. P. Wall, and E. H. Barman, Georgia College & State University, Milledgeville GA 31061. Third instar larvae of Matus bicarinatus, Coptotomus lenticus, Laccophilus maculosus, and Copelatus glyphicus were examined more closely following an earlier study. The mandibles of these taxa were analyzed using biomechanical parameters. The indices used were basal angle, arc, angle of attack, maximum camber, position of maximum camber, and gear ratio. The objective of this assessment was to better understand food acquisition and manipulation via the mandibles using biomechanics. While the basal angles of C. lenticus, L. maculosus, and C. glyphicus appear to be similar, M. bicarinatus has a larger basal angle. C. lenticus has the smallest arc; C. glyphicus has the largest arc. C. glyphicus and C. lenticus have similar angles of attack, while M. bicarinatus is slightly larger and L. maculosus shows the largest angle of attack. M. bicarinatus, C. lenticus, and L. maculosus display comparable maximum camber; however, C. glyphicus has a somewhat greater maximum camber. Values obtained for position of maximum camber appear to be very similar between taxa. Gear ratio analysis indicates that the mandibles of M. bicarinatus, C. lenticus, and L. maculosus seem to be optimized for force of closure, whereas the mandibles of C. glyphicus appear to be optimized for opening speed. This project was supported in part by a Faculty Research Grant, Office of Research Services, Georgia College & State University. Aquatic Coleoptera Laboratory Project No. 65.
AN EVALUATION OF THE PREFERENCE OF THE YELLOW BELLIED- SAPSUCKER FOR THE HOPHORNBEAM OVER THE IRONWOOD **, Catrice Hayes * and Jim Ferrari, Wesleyan College, Macon, GA 31210. The Yellow-bellied Sapsucker, Sphyrapicus varius, uses as one of its food sources phloem sap obtained by drilling holes into living trees. Two tree species within the birch family, ironwood (Carpinus caroliniana) and hophornbeam (Ostrya virginiana), were examined to determine if the sapsucker attacked one preferentially over the other. In a randomly chosen plot containing 117 hophornbeam and 50 ironwood trees, the trees were labeled and tagged. Five characteristics of these trees were measured and tabulated. These characteristics were 1) tree vigor 2) diameter of tree at breast height (dbh) 3) the height of the tree 4) the presence of fungi and 5) the sapsucker damage at various heights. A chi-square test of association showed that the Yellow-bellied Sapsucker preferentially attacked hophornbeam more than ironwood ([X.sup.2] = 8.296, df = 1, P <0.01). In both hophornbeam and ironwood, Yellow-bellied Sapsuckers preferentially attacked larger trees (dbh 10.0 - 22.0 cm) over smaller ones (dbh 2.5 - 9.9 cm; [c.sup.2] = 45.8, df = 1, P <0.001). A variety of hypotheses for the Yellow-bellied Sapsucker's preference of hophornbeam over ironwood are being tested. Sap sugar content will be measured using a hand refractometer and soil moisture content will be measured gravimetrically. A torque wrench will be utilized to determine the force that is required to turn the wrench which will be taken as a measure of wood density. Bark thickness and moisture content, along with tree vigor, soil pH, and relative abundance, will be also tested.
HISTOPATHOLOGICAL CHANGES DUE TO INFECTION BY ASPERGILLUS FLAVUS IN PEANUTS, Karen Hermetz * (1), Premila Achar (1), Robert P. Apkarian (2), and Jeanette Taylor (2), (1) Kennesaw State University, Kennesaw, GA 30144 and (2) IM&MF at Emory University, Atlanta, GA 30322. Aspergillus flavus can invade peanuts in the field before harvest, or poor storage can lead to infection by the mould, releasing carcinogenic aflatoxins. A thorough understanding of the host-pathogen interaction between peanuts and A. flavus may provide information to develop novel detection and screening methods for peanuts. The aim of this study was to establish the seed-borne nature of A. flavus and its significance in seedling infection using light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Results revealed dramatic differences between healthy and diseased tissues. The fungus infected the host tissues, both intercellular and intracellular, aided by haustoria-like structures. While the fungal matrix contained a normal complement of cell organelles and several lipid droplets, cells of the invaded host tissues were irregular or completely destroyed. Moreover, cell wall lysis, granulation of cytoplasm, shrinkage of the protoplast, and cell wall disruption were very common. There were fewer chloroplasts in the diseased compared to healthy leaf tissues and the plasmalemma was pulled away from the cell wall. Infection led to collapse of the stomata, general disorganization of cell organelles, and necrotic collapse of the diseased tissues. Since the mycelium of A. flavus establishes in the seed to a great extent, the present investigation reveals that the peanut seeds are an important source of inoculum for seedling infection and contamination from one seed to another at storage and elsewhere.
THE ECOLOGY OF THE SNAIL LITTORARIA IRRORATA IN TWO GEORGIA SALT MARSHES, Chad Hubbard *, Kelly Kutrufis *, Anthony Zukoff and Sophie B. George, Georgia Southern University, Statesboro, GA 30458. The purpose of this study was to document the distribution and abundance of snails, vertical migration up Spartina alterniflora stems, and predation intensity on snails at two Georgia salt marshes. From May through October 2005, a 50x50 cm quadrat was laid randomly 10 times in each of three zones at low tide. Spartina height, the height of each snail on Spartina sp. stalks, snail length and any damages on snails were noted. Size frequency distribution varied throughout the summer between sites and zones. At the Tybee Island salt marsh, snails were significantly larger and more abundant in the high zone and significantly smaller and less abundant in the mid and lower zones. Though a similar trend was observed at the Crooked River site, the percentage of large snails was significantly lower at this site than at Tybee Island. At both sites, snails were significantly higher up Spartina stalks in the lower zones where stalks were taller than in the upper high zone where the stalks were shorter. The size range of snails most vulnerable to predation at Tybee Island varied from 12.5 to 20 mm in height, and the most common type of damage observed was fractures followed by holes + chips, and fractures + chips. Differences in snail size frequency distribution between zones and sites might be due to variation over time in predator size, species and predation intensity. Destruction of high marsh might lead to the disappearance of large snails and the loss of a major food source for blue crabs, mud crabs, birds and other predators in the salt marsh.
A LIGHT AND SCANNING ELECTRON MICROSCOPE STUDY OF THE MARINE DIATOM NEOHUTTONIA REICHARDTII (GRUNOW) KUNTZE (TRICERATIACEAE), A. K. S. K. Prasad (1) and J. A. Nienow * (2), (1) Florida State University, Tallahassee FL 32306, (2) Valdosta State University, Valdosta GA 31698. Neohuttonia reichardtii (Grunow) O. Kuntze is a distinctive, but rarely reported, marine diatom from tropical and subtropical waters. Its presence in samples from the Gulf and Atlantic coasts of Florida prompted us to perform a more thorough investigation of its structure, including a critical examination of Grunow's original material in the Grunow Collection in Vienna and the Hustedt Collection in Germany. Examination of Slide 796 in the Grunow Collection confirmed the identity of our specimens; we propose to designate this slide as the lectotype of the basionym Cerataulus? reichardtii Grunow. SEM observations revealed the fine structure of the two large ocelli on the mantle and of the transapically-oriented pseudosepta. The areolae appear to be pseudoloculate. There is a single, simple median rimoportula on the valve mantle. No strutted processes, occluded processes, or any type of linking spines were observed. The epicingulum consists of at least four open bands--the valvocopula and three ligulate pleurae. The structures of the ocelli and the areolae suggest that Neohuttonia reichardtii is more closely allied with the Triceratiaceae/Eupodiscaceae, as suggested by Simonsen (1979) and Garcia (2004), than with the Biddulphiaceae, as suggested by Nikolaev and Harwood (2000).
INFAUNAL COMMUNITIES IN HEALTHY AND UNHEALTHY MARSHES OF SOUTHEASTERN GEORGIA **, Anthony Zukoff *, Sophie George, Georgia Southern University, Statesboro, GA 30458. The preservation of Georgia's coastal environment and the health of salt marshes depend upon determining the extent to which the epifauna and infauna have been affected by recent die-offs along the Georgia coast and developing recommendations for conserving and restoring these areas. A coast-wide survey conducted by the Georgia DNR, the University of Georgia, and Savannah State University indicated that epifaunal abundance did not differ between healthy and unhealthy marsh. In the present study, six 0.5 x 0.5 m permanent quadrats were set up in spring 2005 at four sites (two healthy, two unhealthy) along the Crooked River in Camden County, GA. In June, July, August and October, three random core samples 8 cm deep were collected with 50 ml centrifuge tubes from each permanent quadrat (18 core samples/site/month) for a total of 288 core samples. In the laboratory, each core was separated into meiofaunal and macrofaunal components and examined under a microscope after preserving and staining with Rose Bengal in 70% alcohol. Results indicate a lower abundance and lower diversity of infaunal organisms from an unhealthy site and a higher abundance and diversity from a healthy site. Tanaids, nematodes and a variety of polychaetes were abundant at the healthy site. Only one species of polychaete and an abundance of individuals belonging to the phylum Kinoryncha was associated with the unhealthy site.
Section II: Chemistry
B-1900
Kenneth Martin, presiding
7:45 DEVELOPMENT OF AN EFFICIENT ROUTE TO A WIDE VARIETY OF HIGHLY FUNCTIONALIZED AROMATICS FOR USE AS PROBES IN CHEMICAL BIOLOGY, Omar Khatib *, Kevin M. Bucholtz, Department of Chemistry, Mercer University, Macon, GA 31204. In the developing field of chemical biology many endeavors utilize small organic molecules to perturb a particular life process and determine the resulting consequence. With this approach, there is a necessity for the development of new synthetic transformations that allow for a very...
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