Marine bivalves of the Florida Keys: discovered biodiversity

Malacologia, 2004

Marine bivalve biodiversity in the waters surrounding the Florida Keys, an island archi-pelago off southern Florida, including the Florida Keys National Marine Sanctuary, was studied from ten years of original collections as well as from a critical review of museum specimens and literature data. A database of more than 12,000 records representing 389 species (half of which were ranked as abundant or common) was assembled and analyzed, resulting in a 139% increase of the known bivalve fauna of this region compared to the most recent prior (1995) checklist. Of the 389 species, 42% have not been positively recorded as live-collected, and 12.5% are represented only as singletons or doubletons. Using multivariate non-metric statistics and a priori geographic groupings along the island chain (Upper, Middle, Lower Keys; Dry Tortugas) and across the island chain (Florida Bay, shallow Atlantic waters [< 35m], deeper Atlantic waters [35−300 m]), the data showed distinct differences in benthic community structure across several spatial gradients. A pronounced northeast-to-southwest gradient was found on the Florida Bay-side of the island chain, although none was evident along the oceanside in either shallow or deep depth zones. Although they shared dominant species, the shallow-water communities of bayside and oceanside differed significantly in the percentage distributions of co-occurring species. In contrast, the deeper oceanside community differed substantially from both shallow-water groups in supporting a different set of species. A comparison of the bivalve fauna of the Keys with other well-documented faunas of the western Atlantic indicated that the Florida Keys fauna groups more closely to the Gulf of Mexico and Cuba than to eastern peninsular Florida, Yucatan, or the Bahamas. The impact of the heterogeneous nature of the dataset (live-specimen, dead-shell; and original collections, museum, and literature) is discussed and compared to analyses based on live-only data: the latter resulting in less spatial resolution but the same general patterns. In a comparison of data sources (original collections, museum records, gray literature and traditional literature), original collections were least effective (51%) in capturing the total species list despite representing approximately half of the total records. Literature was most successful (90%) in capturing the list but only when gray literature was included. Rapid assessment methods contrasted against the long-term results showed effectiveness when based on a range of sample types and habitats

Malacologia, 2004

Literature data contributing to a biodiversity survey of bivalve species of the Florida Keys are presented in the form of 361 annotated references and a documented species list. 389 species are recorded as identified to at least the species level; all except ten species can be traced to at least one literature citation. Thirty-one nominal species-level taxa were originally described from Florida Keys material or had their type localites designated as such. Annotations on synonyms, confirmed or suspected misidentifications, and a discussion of problematic geographic information are included, as tools for accessing and interpreting the full body of literature, including 19th century works and 91 entries of "gray" literature (i.e., non-peer-reviewed reports, newsletters, unpublished dissertations, websites, etc.). This paper provides supporting data for an analysis of the bivalve fauna of the Florida Keys, based on a new database of over 12,000 original, museum, and literature records, included elsewhere in this volume.

Eight species from three bivalve families were collected and/or observed in the MiddleFlorida Keys. Diagnoses based on shell characters are given for Botula fusca, Lithophagaantillarum, L. aristata, and L. bisulcata in the Mytilidae, and Gastrochaena hians in theGastrochaenidae. Shell and anatomical comparisons are made for three members of thePetricolidae, Petricola lapicida, Choristodon robustum, and Choristodon sp. A, which isnot attributable to a described Recent Choristodon species. These bivalves bore into limestone and dead coral, and in one case into living coral.Observations substantiated previous findings of primary chemical boring processes in Botulaand Petricola.

Malacologia, 2004

To broaden the anatomical knowledge of marine bivalves, detailed gross anatomical studies of 20 species from the Florida Keys are presented, representing 19 families: (Cardiidae) and Scis-sula similis (J. Sowerby, 1806) (Tellinidae). These taxa represent various clades of the class Bivalvia and interface with broader regional and phylogenetic studies (e.g., the Bivalve Tree of Life, http://www.bivatol.org, and Bivalves-in-Time-and-Space, http://www.bivatol.org/bits), in which many serve as exemplar species in different contexts. These descriptions provide the most complete anatomical descriptions yet presented for all species, most especially for Solemya occidentalis, Limopsis aff. cristata, Hyotissa mcgintyi, H. hyotis, Carditamera flori-dana, Entodesma beana, Chama macerophylla and Polymesoda floridana, for which no or only minimal anatomical information has been previously published. This work presents the first anatomical description of any species of Scissula, based on S. similis. Two controversial characters – the promyal passages (in Hyotissa spp., in Anomia simplex noted here for the first time, and in Crassostrea reported in the literature) and the various kinds of posterior apertures and siphons present in the species examined and across the Bivalvia – emphasize the need for further comparative study to confirm homologies. Conspecificity of Brazilian material with that from the North American coast is clarified for all species, resulting in nine species being removed from Brazilian checklists (S. occidentalis, B. exustus, I. alatus, P. carnea, C. floridana, C. macerophylla, L. hians, L. serratum, and S. similis). Pertinent anatomical characters are summarized in a data matrix, and an analysis is provided to demonstrate the utility and resolving power of such characters (but from this limited taxon sampling is not intended to provide a revised phylogenetic hypothesis of bivalve relationships); data for three additional species from Florida, published earlier, are included in the analysis and discussion.

Community composition of the infaunal bivalve fauna of the St. Lucie Estuary and southern Indian River Lagoon, eastern Florida was sampled quarterly for 10 years as part of a long-term benthic monitoring program. A total of 38,514 bivalves of 137 taxa were collected and identified.We utilized this data, along with sediment samples and environmental measurements gathered concurrently, to assess the community composition, distribution, and ecological drivers of the infaunal bivalves of this estuary system. Salinity had the strongest influence on bivalve assemblage across the 15 sites, superseding the influences of sediment type, water turbidity, temperature and other environmental parameters. The greatest diversity was found in higher salinity euhaline sites, while the greatest abundance of individual bivalves was found in medium salinity mixohaline sites, the lowest diversity and abundances were found in the low salinity oligohaline sites, demonstrating a strong positive association between salinity and diversity/abundance. Water management decisions for the estuary should incorporate understanding of the role of salinity on bivalve diversity, abundance, and ecosystemfunction.

As part of an U.S. EPA/USGS project to predict the relative vulnerability of near-coastal species to climate change along the Pacific Coast, we have synthesized the biogeographic distributions and abundances of bivalves found in depths &lt;200 m. We have included the twelve “Marine Ecoregions of the World” (MEOW) ecoregions that range from the Beaufort Sea to the Gulf of California (GOC). The biogeographic patterns and life history traits are being synthesized in a web-based tool, the Coastal Biogeographic Risk Analysis Tool (CBRAT). A total of 889 bivalve species have been reported over this domain, with the GOC having the greatest species richness (627) and the Beaufort the lowest (66). There are 31 endemic bivalves, with the GOC having the majority (19) and Southern California the next highest concentration (8). Of the 71 families present, Veneridae is the most speciose with 86 species, while 10 families are only represented by a single species, of which two are considered nonind...

In spite of the high species diversity and commercial importance of bivalve mollusks, there appears to be a recent decline in the amount of published research on this fascinating group (Morton, 1992). With this in mind, Brian Morton, Gene Coan, and Paul Scott set about to generate new interest in bivalves, and present an opportunity for many bivalve workers to exchange ideas and techniques. The 1991 bivalve symposium in Berkeley, California, sponsored by the American Malacological Union and the Western Society of Malacologists, was the initial step in bringing researchers together (see proceedings in American Malacological Bulletin 9(2):105-215). Following the symposium, the California Malacozoological Society and the Western Society of Malacologists sponsored a workshop at Moss Landing, California from 5-1 9 July 1991. The eight papers that follow in this issue of Ihe Veliger represent research that was begun during the workshop.

Bulletin of Marine Science, 2007

A study of the rocky intertidal environments of the Florida Keys by Stephenson and Stephenson (1950) serves as a valuable baseline of littoral communities prior to extensive development and human population pressures. Five of the study areas originally surveyed in 1947 were resurveyed in 1999 to assess any community changes which may have occurred in the intervening 52 yrs. A more extensive sampling effort in 1999 yielded a greater number of taxa as compared to 1947 (120 vs 78). However, one intertidal zone showed a decrease in taxa richness, not all species recorded in 1947 were seen in 1999, and others had shifts in abundance or zones of occurrence. The gray zone at the high mean water mark may have experienced degradation from the deposition of seagrass, debris, or hydrophobic substances as suggested by a 79% decrease in the species that occurred there, despite an increase in the number of species found in all other zones. Harvesting, pollution, or general habitat degradation may explain the complete absence or reduced abundance of some species, particularly those considered as dominant or characteristic intertidal community members in 1947. Increased nearshore eutrophication and/or changes in grazer communities may explain an apparent upward shift of some macroalgal species and the appearance at more heavily developed sites of algal nutrient indicator species (e.g., Cladophora, Chaetomorpha, and Enteromorpha). Our results are consistent with increasing evidence that disturbances, such as eutrophication, are having a negative effect on rocky intertidal communities of the Florida Keys.