U.S. DEPARTMENT OF THE INTERIOR 

U. S. GEOLOGICAL SURVEY

Benthic Foraminifera and Ostracoda from Virginia Continental Shelf

By Thomas M. Cronin, Scott Ishman, Robert Wagner 

U.S.Geological Survey 

Reston, Virginia 20192

and

G.R. Cutter, Jr.

Virginia Institute of Marine Science 

Gloucester Point, Virginia 23062

OPEN-FILE REPORT 98-29

Prepared in collaboration with Virginia Institute of Marine Science for Minerals 

Management Service, Office of International Activities and Marine Minerals Agreement 

No. 14-35-0001-30807.

This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial 

standards nor with the North American Stratigraphic Code. Any use of trade, product, or firm names is 

for descriptive purposes only and does not imply endorsement by the U.S. Government.
Introduction

Benthic meiofaunas living on continental shelves comprise a significant proportion 

of the total biomass and species diversity in shallow marine environments and play 

important roles in the functioning of shallow marine ecosystem. Two important meiofaunal 

groups, benthic foraminifers (protists) and ostracodes (bivalved Crustacea), have been 

especially important in studies of benthic communities living along the U.S. Atlantic 

continental shelf. Buzas and Culver (1980) estimated that the number of benthic 

foraminifers in marine environments exceeds 10 6 per square meter and wet-weight 

biomass ranges from 0.02 to more than 10 g/m2 . Numerous other studies have 

documented the zoogeographic and bathymetric distribution of more than 800 species of 

benthic foraminifera (e.g., Culver and Buzas 1980; Buzas and Culver 1980) and several 

hundred species of marine ostracodes (Valentine 1971; Hazel 1970, 1975; Cronin 1983) 

along the U.S. Atlantic coast.

Most previous studies of Atlantic continental shelf foraminifers and ostracodes, 

however, were conducted at very large spatial and temporal scales. For example, the large 

USGS/Woods Hole Continental Margin Program which took thousands of Atlantic shelf 

and slope sediment samples during the 1960's (Emery 1966) provided extensive ostracode 

zoogeographic data spanning several marine zoogeographic provinces and climatic zones 

(e.g. Hazel 1970). Likewise, Culver and Buzas (1980) compiled foraminiferal species' 

distribution data from hundreds of published sources to produce distribution maps of the 

150 most common species for the western North Atlantic Ocean. Prior studies of fossil 

benthic foraminifers and ostracodes of the Atlantic margin have also focused on long-term 

changes in microfaunal assemblages resulting from glacial-interglacial climatic cycles 

(Hazel 1968; Cronin 1988) and from community evolution over millions of years (Buzas 

and Culver 1984, 1989).

While these studies of living and fossil foraminifers and ostracodes provide 

excellent baseline information, they are insufficient to understand the small scale
distribution of species within a limited region of the continental shelf, nor to understand 

short-term variability in meiobenthic populations. Such information is essential in the 

evaluation of potential impacts of short-term environmental disturbances from sand mining, 

pollution and nutrient influx or high-frequency climatic variability on continental shelf 

ecosystems.

Our main goal in the present study is to provide baseline information on the 

abundance and species diversity of foraminiCers and ostracodes living in three potential 

sand mining areas off Virginia Beach. This study was carried out in collaboration with the 

Virginia Institute of Marine Science, College of William and Mary, in support of the 

Minerals Management Service program to understand environmental aspects of potential 

sand mining off the city of Virginia Beach, Virginia

Study Area

The study region is located in the warm temperate marine climatic zone of the

western North Atlantic Ocean between about 36.7 to 37.91 ° N and 75.85 to 75.92 ° W.

(Figure 1). The oceanography of the region is dominated by the cool, southward flowing 

Virginia Coastal Current and the warmer, northward-flowing Gulf Stream/Florida Current. 

These currents converge near Cape Hatteras where strong isothermal convergence creates 

thermal barriers to the poleward and equatorward distribution of thermophilic (warm water) 

and cryophilic (cool water) species respectively. Off southeastern Virginia, the coldest

bottom waters usually occur during February and range from about 5 to 10 °C, with 

generally cooler temperatures closer to shore. The wannest temperatures occur in AugustSeptember, reaching > 25 °C, decreasing offshore to 17-20 °C in the middle shelf region

(Walford and Wicklund 1968).

On the geographic scale of faunal provinces, winter and/or summer bottom water 

temperatures are dominant factors influencing large-scale latitudinal distribution of
ostracode and foraminiferal species on continental shelves (Hazel 1970). The Virginia shelf 

is located just north of the major zoogeographic boundary near the Cape Hatteras region. 

The benthic fauna off southeastern Virginia is composed mainly of temperate species 

common in regions north of Cape Hatteras. Many species living on the Virginia shelf are 

near the southernmost limit of their latitudinal distribution because either they cannot 

tolerate wanner water temperatures to the south or they require cooler winter temperatures 

for survival and/or reproduction (Hazel 197Q).

As one moves from nearshore to offshore regions of the Atlantic margin (from the 

continental shelf to the slope), factors such as dissolved oxygen, light penetration, 

sediment texture and composition, and decreasing temperatures of the thermocline affect the 

distribution of species. For example, environmental gradients at the shelf/slope transition 

result in a major bathymetric turnover of benthic ostracode (Cronin 1983) and foraminiferal 

species (Culver and Buzas 1983) between 150-500 m water depth. All the samples in the 

present study came from the mid- to inner continental shelf and the studied fauna is not 

affected by the thermocline or by hypoxia.

Substrate is another important factor in the small-scale distribution of benthic 

foraminifers and ostracodes. Buzas et al. (1989), for example, conducted experiments with 

benthic foraminifers and showed a small amount of mud in a sandy benthic habitat can have 

important affects on benthic foraminiferal densities. Many ostracode species are also 

substrate-specific in nearshore and estuarine habitats (Cronin 1979). The shelf off 

southeastern Virginia is mainly composed of sands (Hollister 1973) and provides an ideal 

substrate for sand-dwelling taxa.

Methods

Surface sediment samples were collected on May 15 and June 5-6,1996 (Spring 

samples) and October 21 and November 6,1996 (Fall samples) from the VIMS R/V Bay 

Eagle. Collections were made from three regions which are referred to here as the
northern, central and southern regions. There are no obvious barriers between or 

environmental differences among the three regions. All three are characterized by sandy 

substrates and generally similar temperature and salinity regimes. The regions were 

divided into a grid like pattern using longitude and latitude. Each square of the grids was 

considered a cell. These individual cells were assigned numbers 1-400. Of these, 39 were 

sampled for the Spring and 25 for the fall. Figure 2 shows the location of all the cells that 

were sampled. Figures 3-12 show sample stations for designated seasons; Appendices 1-3 

give the latitude and longitude for each station. Additional information about the cruises 

can be found in the companion report by Diaz, Cutter et al. (in press).

Samples were obtained using a Smith/Mclntyre grab sampler. Surface sediment 

from the uppermost 1-2 cm was scraped from a 10 cm2 area within the grab sample and 

placed in plastic sample bags. The sediment samples were immediately stained shipboard 

with Rose Bengal to help distinguish between living and dead ostracodes and foraminifera 

(see Walton 1952).

Surface sediment samples were processed for foraminifera and ostracodes using

standard procedures. The sediments were washed through a 63 |nm sieve and dried at

50°C at VIMS laboratories. A total of 300 benthic foraminifers were picked from the

residues when available. Samples yielding fewer than 300 specimens were picked of all 

the foraminifera present. All the samples in Appendices 1 and 2 contained stained 

representatives and we assume the populations represented at each site were living close to 

the time of collection. A total of 20 foraminiferal species were found.

Ostracodes were picked at the same time as foraminifers from the same quantity of 

sediment needed to obtain 300 foraminifers (time constraints did not allow us to pick the 

entire sample). Ostracodes occurred in most samples; they are typically less abundant than 

foraminifers in sandy substrates such as those of the Virginia shelf (the number of
ostracodes specimens ranged from 0 to 36 per sample) compared to finer grained 

substrates of Atlantic estuaries and offshore continental slope regions.

A total of 31 ostracode species were found in the Virginia sandy shelf habitats. 

Many individual ostracodes (especially P. edwardsi, P. bradyi, C. seminuda, and 

Bensonocythere) were preserved as whole carapaces containing chitinous appendages and 

other "softparts". These specimens stained vivid pink and clearly were living at the time of 

collection. Other specimens, notably juvenile valves, stained faint pink in color and very 

likely represent the molt stages of living populations.

Foraminifera and ostracodes were examined under light and electron microscopes at 

the U.S. Geological Survey in Reston, Virginia. Specimens were identified to species 

level using USGS reference collections, following the taxonomy of Culver and Buzas 

(1980) and Loeblich and Tappan (1988) for foraminifers and Valentine (1971), Hazel 

(1975, 1983), and Cronin (1990) for ostracodes. The faunal slides containing 

foraminiferal and ostracodes are housed in the USGS microfaunal reference collections, 

Reston, Virginia 20191.

Results

The foraminiferal and ostracode species census data are given in Appendices 1-3 

and are available electronically from the authors (tcronin@usgs.gov). Figures 2-11 plot the 

distribution of more common species of foraminifera and ostracodes; Plates 1-5 illustrate 

most of the identified species with scanning electron photomicrographs.

Ostracodes

A total of 31 species of ostracode were found in the study area. The ostracode 

assemblage is dominated by Peratocytheridea bradyi, Hulingsina sp., Cushmanidea 

seminuda, and Protocytheretta edwardsi. These species are typical inhabitants of sandy
inner continental shelf environments of the temperate marine climatic zone of the Atlantic 

margin off the eastern United States.

The total species number and the composition of the ostracode assemblage is 

remarkably similar to that collected 30-35 years ago during the USGS-Woods Hole 

Oceanographic Institution (WHOI) Continental Margin Program (Emery 1966). A 

comparison between the assemblage found at station 43 of Valentine (1971) located near 

the current study area with our total 1996 assemblage indicates that Valentine found the 

same 31 species at this site in the 1960's sample found in the current study. These results 

leads to a fundamental conclusion from the current study that there has not been a long-term 

change in the overall ostracode assemblage at this site.

Although the overall ostracode fauna! assemblage has not seen any net change over 

the past 30 years, we discovered important heretofore undiscovered seasonal and onshoreoffshore variability in ostracode distributions revealed from the 1996 sampling program 

(Figures 6-11). Among the highlights:

 Several key ostracode species (Loxoconcha williamsi, Hulingsina rugipustulosa, 

Cushmanidea seminuda) have a more limited distribution in the Spring than in the Fall, 

suggesting there is a seasonal migration into new habitats during the Summer and early 

Fall months.

 The pattern of Summer/Fall range expansion may be related to the predominant 

southward direction to bottom drift of this region which may also be related to the 

prominent sand-swell crests in many regions of the mid-Atlantic shelf (Uchupi 1968; 

Hollister 1973).

 Several other species contract their range between the Spring and the Fall seasons. 

Peratocytheridea bradyi contracts its range from the northern and southern regions to 

only the southern region in the Fall. Hulingsina americana and Protocytheretta edwardsi 

are present in northern/central and northern/southern regions in the Spring, 

respectively, but they are almost totally absent from all samples taken in the Fall.

7
 The Virginia continental shelf contains several species encountered in sediments 

deposited over the past 1000 years in Chesapeake Bay. The shelf seems to serve as a 

source area for ostracodes species which periodically inhabit the more saline southern 

part and the deeper channel of Chesapeake Bay especially during periods when river 

discharge is reduced (Cronin unpublished data).

These results provide strong evidence that ostracode species have distinct 

population ecology linked to seasonal variability of the continental shelf. Major seasonal 

changes in ostracode populations have also been documented in estuarine ostracodes in the 

Patuxent River (Tressler and Smith 1948) and in Sippewisset Marsh, Cape Cod 

(Schweitzer and Lohman 1990) but until this time, were unknown for shelf species. We 

believe the southeastern Virginia 1996 data is the first to document such seasonality in 

Atlantic shelf marine ostracode distributions. Although additional analyses are merited to 

further document seasonal trends, we suspect that seasonal variability is related to bottom 

water currents. Southward flowing currents are considered especially important in 

affecting the distribution of Loxoconcha williamsi, Hulingsina rugipustulosa, Cushmanidea 

seminuda.

Benthic Foraminifera

A total of 20 species were identified from the surficial sediment samples. The 

dominant genus is Elphidium, a genus that includes several species common in nearshore 

environments of the North Atlantic Ocean. Elphidium is represented by three subspecies of 

E. excavatum (these are sometimes referred to separate species or distinct morphotypes of 

the same species): Elphidium excavatum clavata, E. excavatum selseyensis, and E. 

excavatum excavata. Figures 2 and 3 show the distributions of E. excavatum selseyense, 

the most abundant species found in our study, and E. excavatum clavata during Spring and 

Fall 1996.

8
Elphidium excavatum selseyensis is the dominant benthic foraminifer on the 

Virginia Beach continental shelf comprising up to 93% of the assemblage. The Spring 

distribution of E. selseyensis shows it comprises greater than 80% of the assemblage in 

northern and central areas, and 70% to 80% of the assemblage in the southern region. The 

distribution of E. selseyensis in the fall is reduced with a greater than 80% occurrence in 

the northern and central areas, and 60% to 80% in the southern area and the southern part 

of the central area.

Elphidium excavatum clavata is the dominant benthic foraminifer in the northern 

and southern areas. It makes up a much smaller percentage (< 8%) of the assemblage in 

the central area. This species expands to significant proportions in the fall where it 

composes greater than 8% (sometimes exceeding 16%) in much of the central and southern 

regions.

The occurrence off southeastern Virginia of these forms of the genus Elphidium is 

consistent with benthic foraminifer distributions reported from the mid-Atlantic continental 

shelf of North America. Murray (1991) and Culver and Buzas (1980), for example, 

mapped the Elphidium predominance from Cape Cod to Cape Hatteras and off the North 

American Atlantic coast, respectively. Schnitker (1971) also found an abundance of 

Elphidium clavatum north of Cape Hatteras on the inner shelf.

Other species occurring on the Virginia shelf, in order of abundance, include 

Quinqueloculina seminula, Ammonia parkinsoniana, Buccellafrigida, Hanzawaia 

atlanticus, Hanzawaia concentrica and Eggerella advena. Figures 4 and 5 show the 

distribution of A. parkinsoniana and Q. seminulum during Spring and Fall, 1996; plates 4 

and 5 illustrate most of these species.

Although the relative abundances of Ammonia parkinsoniana in the Virginia Beach 

shelf samples are low, 5% or less, the distribution of this species seems to reflect distinct 

environmental conditions in the central study area. A. parkinsoniana is common 

throughout the world in estuarine environments due to its tolerance of highly fluctuating
salinities ranging from brackish (oligohaline, 0.5-5 ppt) to hypersaline (>40 ppt). It lives 

on the surface of fine-grained sediments down to a depth of 10 cm into the substrate and 

has a complex life history involving bacterial and algal endosymbionts (Goldstein and 

Moodley 1993). Chandler et al. (1996) found that Ammonia would only reproduce in 

culture under specific conditions that included the addition of silty-clay obtained from the 

Gulf of Mexico and a regular diet of phytoplankton.

The Spring distribution of A. parkimoniana shows its greatest abundance in the 

southern part of the central area with only sparse occurrences in northern and southern 

regions. The fall distribution of A. parkinsoniana shows a slight expansion into the 

northern and western sections of the central area 2 but it is still rare to absent in northern 

and southern regions. It is unlikely that salinity variations restricted A. parkinsoniana from 

inhabiting northern and southern regions. Rather, we suspect that its limited range has 

more to do with resource limitations such as the availability of food, nutrients and/or finer 

grained sediments which may be available in the central region.

Quinqueloculina seminula is the dominant miliolid foraminifer that occurs in our 

surficial samples. It is present in percentages ranging from 5-10% to 20-25% in the central 

and southern regions in the Spring. However, its distribution changes in Fall when it 

expands into the northern region but disappears in parts of the central region. In the Fall its 

abundance is greatly reduced to < 2 %.

Conclusions

The modern benthic foraminiferal and ostracode faunas from three areas on the 

Virginia Beach continental shelf allow several important new conclusions about the 

meiobenthic fauna of sandy substrate environments of the continental shelf off Virginia 

Beach, Virginia.

10
 The 1996 faunal assemblages are extremely similar in species composition to those 

obtained in previous sampling program of the North American Atlantic continental shelf 

conducted during the 1960's. There has been no major long-term changes in the faunas 

from these regions.

 Seasonal benthic foraminiferal and ostracode distribution data show that significant 

changes in the relative abundance of the dominant species characterize the Spring and 

Fall assemblages. Several ostracode species expand their range southward from Spring 

to Fall suggesting bottom drift currents may play a role in seasonal dispersal of 

populations. Other ostracode species are common in the Spring but are almost totally 

absent in the Fall reflecting a complex, still poorly known population ecology.

 Foraminiferal species richness and geographic distributions are slightly greater in the 

fall with the expansion of the species E. clavata, A. parkinsoniana, and Q. seminula, 

and reduction in spatial distribution of E. selseyensis.

 Ammonia parkinsoniana has a distinct range limited to the central study region, 

possibly due to food and/or substrate limitations.

 The Virginia shelf is an important source habitat for species migrating into Chesapeake 

Bay. Two examples are the ostracode species, Loxoconcha williamsi and 

Protocytheretta edwardsi, which occur commonly on the Virginia shelf and have also 

been discovered in sediments in Chesapeake deposited prior to large-scale land clearing 

of the early 19th century.

Overall, our preliminary results indicate that a complex meiobenthic community 

inhabits the southeastern Virginia shelf. It is very likely that the entire community is 

potentially sensitive to environmental disruption to surficial sediments. However, due to 

the variable ecological requirements of each foraminiferal and ostracode species, the impact 

of habitat disturbance will vary widely among the 50 or so species recovered.

11
Furthermore, whereas the Virginia shelf is itself important habitat for meiobenthic 

species, this region must also be considered an important source area region for species 

able to migrate into coastal estuaries and bays like Chesapeake Bay. Consequently, 

species' population dynamics in the shelf region must be examined in the context of 

seasonal monitoring of conspecific populations living in adjacent areas.

Additional benthic sampling of the Virginia shelf through a second seasonal cycle, 

new sampling of the Virginia shelf/Chesapeake Bay mouth transition, supplemented by 

physical and chemical oceanographic data, would provide an ideal platform from which to 

fully understand shallow marine foraminiferal and ostracode species ecology and determine 

the least disruptive way to mine sand from shelf regions.

Acknowledgments

This study was conducted by the U.S. Geological Survey and Virginia Institute of 

Marine Science for Minerals Management Service, Cooperative Agreement No. 14-35-001- 

30807. We appreciate the encouragement of Barry Drucker of MMS during the course of 

this program, especially his support of multidisciplinary environmental studies of the 

continental shelf ecosystems. This study would not have been possible without the support 

and insights of C. H. (Woody) Hobbs, III and Robert Diaz of VIMS. We are grateful to 

the captain and crew of the Bay Eagle for their assistance in obtaining the samples for this 

study. Special thanks go to Colleen Cunningham for her diligence and patience in 

processing and picking foraminifera and ostracodes. Debra Willard and Scott Ishman 

kindly provided useful reviews of this report.

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Buzas, M. A. and S. J. Culver. 1980. Foraminifera: distribution of provinces in the 

western North Atlantic. Science, 209: 687-689.

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Buzas, M. A. and S. J. Culver. 1984. Species duration and evolution: benthic foraminifera

on the Atlantic continental margin of North America. Science, 225: 829-830. 

Buzas, M. A. and S. J. Culver. 1989. Biogeographic and evolutionary patterns of

continental margin benthic foraminifera. Paleobiology, 15: 11-19. 

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predation, substrate preference, and colonization of benthic foraminifera at the

shelfbreak off the Ft. Pierce Inlet, Florida. Journal of Foraminiferal Research, 19:

146-152. 

Chandler, G. T., D. F. Williams, H. J. Spero, G. Xiaodong. 1996. Sediment microhabitat

effects on carbon stable isotopic signatures of microcosm-cultured benthic

foraminifera. Limnology and Oceanography, 41: 680-688. 

Cronin, T. M. 1979. Late Pleistocene marginal marine ostracodes from the southeastern

Atlantic Coastal Plain and their paleoenvironmental interpretations. Geographic

Physique et Quaternaire, 33: 121-173. 

Cronin, T. M. 1983. Bathyal ostracodes from the Florida-Hatteras slope, the straits of

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Series B, 318, no. 1191: 661-678. 

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States Atlantic coastal Plain: Evolution and speciation in Ostracoda IV. U.S.

Geological Survey Professional Paper 1367-C. 

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North American Atlantic coast. Smithsonian Contributions to the Marine Sciences,

6: 512 p.

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Culver, S. J. and M. A. Buzas. 1983. Benthic foraminifera at the shelfbreak: North

American Atlantic and Gulf margins. Society of Economic Paleontologist and

Mineralogists Special Publication No. 33, pp. 359-371. 

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foraminifer Ammonia beccari (Linne) forma tepida (Cushman). Journal of

Foraminiferal Research, 23: 213-220. 

Hazel, J. E. 1968. Pleistocene ostracodes zoogeography in Atlantic coast submarine

canyons. Journal of Paleontology, 42: 1264-1271. 

Hazel, J. E. 1970. Atlantic continental shelf and slope of the United States-ostracode

zoogeography in the southern Nova Scotian and northern Virginian fauna!

provinces. U.S. Geological Survey Professional Paper 529-E. 

Hazel, J. E. 1975. Patterns of marine ostracode diversity in the Cape Hatteras, North

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14
Schnitker, D., 1971. Distribution of foraminifera on the North Carolina continental shelf.

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the ostracode genus Cyprideis. Paleobiology, 16: 107-125. 

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Ostracoda, Solomons Island, Maryland region. Chesapeake Biological Laboratory

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Figure Captions

Figure 1. Map showing general location of Virginia shelf study area.

Figure 2. Map showing the individual cells sampled within the three regions

Figure 3. Distribution map showing the proportions of Elphidium excavatum selseyense in 

total foraminiferal population on continental shelf off Virginia Beach during Spring 

(upper map) and Fall (lower map) 1996. Small dots indicate station locations.

15
Figure 4. Distribution map showing the proportions of Elphidiiun excavatwn clavata in

total foraminiferal population on continental shelf off Virginia Beach during Spring 

(upper map) and Fall (lower map) 1996. Small dots indicate station locations.

Figure 5. Distribution map showing the proportions of Ammonia parkinsoniana in total 

foraminiferal population on continental shelf off Virginia Beach during Spring 

(upper map) and Fall (lower map) 19.96. Small dots indicate station locations.

Figure 6. Distribution map showing the proportions of Quinqueloculina seminulwn in total 

foraminiferal population on continental shelf off Virginia Beach during Spring 

(upper map) and Fall (lower map) 1996. Small dots indicate station locations.

Figure 7. Distribution map showing the number of Peratocytheridea bradyi specimens on 

continental shelf off Virginia Beach during Spring (upper map) and Fall (lower 

map) 1996. Small dots indicate station locations.

Figure 8. Distribution map showing the number of Cushmanidea seminuda specimens on 

continental shelf off Virginia Beach during Spring (upper map) and Fall (lower 

map) 1996. Small dots indicate station locations.

Figure 9. Distribution map showing the number of Hulingsina rugipustulosa specimens on 

continental shelf off Virginia Beach during Spring (upper map) and Fall (lower 

map) 1996. Small dots indicate station locations.

Figure 10. Distribution map showing the number of Loxoconcha williamsi specimens on 

continental shelf off Virginia Beach during Spring (upper map) and Fall (lower 

map) 1996. Small dots indicate station locations.

16
Figure 11. Distribution map showing the number of Protocytheretta edwardsi specimens 

on continental shelf off Virginia Beach during Spring 1996. Small dots indicate 

station locations.

Figure 12. Distribution map showing the number of Hulingsina americana specimens on 

continental shelf off Virginia Beach during Spring 1996. Small dots indicate 

station locations.

17
Scanning Electron Microscope Plates of Virginia Shelf Ostracodes and 

Foraminifera

Plate 1

Figure 1: Bensonocythere sapeloensis Hall 1965. x 134, Sta. 64, Cell 308, female, left 

valve.

Figure 2: Bensonocythere sapeloensis Hall 1965. x 133, Sta. 62, Cell 316, female, right 

valve, internal view.

Figure 3: Bensonocythere sapeloensis Hall 1965. x 141, Sta. 1, Cell 209, male, left valve.

Figure 4: Puriana rugipunctata (Ulrich and Bassler 1904), x 143, Sta. 55, Cell 264, 

female, right valve.

Figure 5: Muellerina ohmerti Hazel 1983, x 178, Sta. 52, Cell 52, female, left valve.

Figure 6: Protocytheretta edwardsi (Cushman 1906)., x 83,4, Sta. 64, Cell 64, female, 

right valve.

Figure 7: Cytherettid, x 71,3, Sta. 62, Cell 316, female, left valve, internal view.

Figure 8: Protocytheretta edwardsi (Cushman 1906, x 91,7, Sta. 204, Cell 204, female, 

left valve, internal view.

18
Plate 2

Figure 1: Hulingsina americana (Cushman 1906). x 88,1 , Sta. 64, Cell 308, female?, 

left valve.

Figure 2: Cushmanidea seminuda (Cushman 1906). x 94,2 , Sta. R2, Cell 185, female, 

right valve.

Figure 3: Sahnia sp., x 141, Sta. 24, Cell 234, male, left valve.

Figure 4: Hulingsina mgipustulosa (Edwards 1944) x 147, Sta. 46, Cell 46, female, right 

valve.

Figure 5: Peratocytheridea bradyi (Stephenson 1938). x 139, Sta. 52, Cell 213, female, 

left valve, internal view.

Figure 6: Peratocytheridea bradyi (Stephenson 1938). x 124, Sta. 209, Cell 209, female, 

left valve.

Figure 7: Peratocytheridea bradyi (Stephenson 1938). x 134, Sta. 51, Cell 204, female, 

left valve, Note hole in middle where predator bored through carapace.

Figure 8: Eucythere declivis (Norman 1865). x 151, Sta. Rll, Cell 49, female?, left 

valve, soft parts.

19
Plate 3

Figure 1: Tetracytherura sp. A of Valentine 1971, x 166, Sta. Rll, Cell 49, male, left 

valve.

Figure 2: Tetracytherura sp. A of Valentine 1971, x 166, Sta. 64, Cell 308, left valve, 

internal view.

Figure 3: Cytherura sp., x 167, Sta. 64, Cell 64, female, left valve. 

Figure 4: Cytherura sp. x 307, Sta. 53, Cell 365, left valve.

Figure 5: Proteoconcha tuberculata (Puri 1960). x 104, Sta. 54, Cell 263, male, right 

valve.

Figure 6: Proteoconcha tuberculata (Puri 1960). x 121, Sta. 53, Cell 246, female?, left 

valve, internal view.

Figure 7: Loxoconcha williamsi (= aff granulata Sars 1865). x 151, Sta. RIO, Cell 66, 

female, left valve.

Figure 8: Cytherura wardensis Howe and Brown 1935. x 176, Sta. 229, Cell 229, 

female, left valve.

Figure 9: Microcythere sp., x 280, Sta. 53, Cell 365, lateral view. 

Figure 10: Microcythere sp. x 307, Sta. 53, Cell 365, dorsal view.

20
Plate 4

Figure 1: Elphidium clavata, x 191, Sta. 52, Cell 213.

Figure 2: E. selseyensis, x 164, Sta. 57, Cell 372.

Figure 3: Quinqueloculina seminuhim, x 122, Sta. 54, Cell 332.

Figure 4: E. clavata, x 176, Sta. 57, Cell 372.

Figure 5: E. selseyensis, x 178, Sta. Rll, Cell 49, aperture L.

Figure 6: Hanzawaia concentrica, x 147, Sta. R9, Cell 104.

Figure 7: Ammonia parkinsoniana, x 176, Sta. R2, Cell 185, spiral side.

21
Plate 5

Figure 1: Buccellafrigida, x 217, Sta. 57, Cell 372, umbilical view.

Figure 2: Ammonia parkinsoniana, x 181, Sta. R14, Cell 24, umbilical view.

Figure3: Planulina mera, x 141, Sta. 52, Cell 213.

Figure 4: Hanzawaia atlanticus, x 122, Sat. R4, Cell 183.

Figure 5: Guttulina lactea, x 176, Sta. 59, Cell 360.

Figure 6: Buccellafrigida, x 217, Sta. R2, Cell 185.

Figure 7: Hanzawaia concentrica, x 151, Sta. 51, Cell 204, flat side view.

22
% %L

"

\


H*'-

Kilometers
Virginia 

Beach

 31

61

13

201 204 209 

213

22S

234 -246 

264 '255

263

24

48 49 SO 

 'BO 

EE

704. .106

137

174. 

.J83. .« 

1S1 -194

176

332

361

307 ' '308

316 

342 ,..'336.347

3ES

360

372 I 377,

390

396

3 Miles

5 Kilometers

Figure . 1996 Smith-Maclntyre grab sample locations, and 

proposed borrow areas (delineated by red lines).
Elphidium excavatum

selseyense 

Spring 1996

| | St2m

Fallfortxt

Surface from Sprfortxt 

r~| 40 - 50

B

50-60 

60-70 

70-80

| | No Data

4 Kilometers

Elphidium excavatum

selseyense 

Fall 1996

I |St2m

Fallfortxt 

Surface from Fall'or.txt

] 40 - 50

j 50 - 60

| 60 - 70 

70-80

| 80 - 90 

__| 90 - 99 

| | No Data

4 Kilometers
Elphidium excavatum ciavata 

Spring 1996

I I St2^

Sprfoaxt

I

0-4-

12- :e

'3-20 

20-24 

No Data

2 4

E!phid:um excavatum ciavata 

Fail 13S6

I I S2rn

efface fr-M:i Fftiliwrtvt

B- 0-12

12- :e 

i 2n - 24
Ammcnia parkinscniana 

Spring 1996

I |S<2m

- Sprfor M 

Surface from Fs..for.txt I 10-1

IB4-5 

No Data

Ammonia park;nsomana 

Pail 1996

- Sprforlxt 

Siiffsc* frsn Pa-for.!:<t

rue--:

H-2

!

: -3 

3-4 

4-6 

' NO Jeta

I

I

024
Quinqueloculina seminulum 

Spring 1996

| |St2m

Fallfortxt

Surface from Sprfor.txt I IO-5 

I 15-10 

HI 10-15

 

15-20 

20-25 

__ 25 - 30 

| | No Data

2024 Kilometers

Quinqueloculina seminulum 

Fall 1996

| |St2m

Fallfor.txt 

Surface from Fallfor.txt

| [0-0.5

r5^ o.s -1

1-1.5

1.5-2

I No Data

2024 Kilometers
Peratccytheridsa bradii 

Spring 19S6

I | St2?ti

prosl:.L;:S 

STJ i :i forest, ^

CH2-3

NO Data

024

Peratocytheridea bradii 

Fall 1996

j | SS2m

Surface from

CH2-3

No Data
Cushrranidea seminuda 

Spring 1996

I ! St2rn

cuH

2-3 

3-3. 

3-4

W-^-E

J. Ui'-^*-- -4- JViCiii

Cushmanidea seminuda 

Fall 1996

j | St2m

. Fa'icsttxt 

Surface from Failosi.tici

B

2-3 

3-3

m 3-4

Vafoforam1.txt

N

t 

W

-A \
Hulingsina rugjpustulosa 

Spring 1996

| | St2m

 Sprost.txt 

Surface from Sprost.txt

B 1-1.5 

1.5-2 

2-2.5 

2.5-3 

I I No Data

w

2024 Kilometers

Hulingsina rugipustulosa 

Fall 1996

I I St2m

' Fallost.txt 

Surface from Fallost.txt 

 1-1.5 

. 1-5-2

Hi 25-3 

 Vabforam1.txt

202468 Kilometers
Loxoconcha williamsi 

Spring 1996

| |St2m

Sprost.txt

Surface from Sprost.txt 

| | 1-2 

| 12-2

J

2-3 

3-4 

| | No Data

w

4 Kilometers

Loxoconcha williamsi 

Fall 1996

St2m 

- Fallosttxt 

Surface from Fallost.txt 

 1-1.5

^1.5-2 

I No Data

w

8 Kilometers
Protocytheretta edwardsi 

Spring 1996

Sprost.txt St2m 

Surface from Sprost.txt

No 3-4 2-32-2

1-2

Data

N

W

4 Kilometers
Hulingsina americana 

Spring 1996

Sprost.txt

St2m

Surface from Sprost.txt 

| J2-2I 11-2 

No Data

N

W

4 Kilometers
Appendix 1: Species Census data of Foramlnlfera on the Virginia Continental Shelf, Spring 1996

Q

5

0)

6/5/96

5/15/96

5/15/96

5/15/96

5/15/96

5/15/96

5/15/96

5/15/96

5/15/96

5/15/96

5/15/96

6/6/96

6/6/96

6/6/96

6/6/96

6/6/96

6/6/96

6/6/96

6/6/96

6/6/96

6/6/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

6/5/96

308

316

360

361

372

332

342

365

377

264

264

246

213

204

263

234

201

205

229

13

24

61

50

49

66

104

106

115

137

181

183

194

185

174

3

75.875

75.883

75.861

75.897

75.892

75.896

75.893

75.881

75.872

75.865

75.865

75.858

75.875

75.872

75.869

75.869

75.885

75.868

75.869

75.93

75.923

75.932

75.916

75.902

75.912

75.915

75.907

75.908

75.9

75.917

75.908

75.903

75.901

75.907

Longitude

36.761

36.758

36.742

36.738

36.733

36.75

36.746

36.738

36.733

36.887

36.887

36.894

36.905

36.908

36.887

36.898

36.908

36.908

36.887

36.878

36.874

36.858

36.867

36.867

36.858

36.843

36.843

36.839

36.832

36.812

36.812

36.808

36.812

36.816

Latitude

i

!

]

! 

i

I 

6

1

I

I

i

I

15

10

8

4

6

3

2

4

4

5

4

3

1

6

1

8

i

17

24

69

13

23

30

38

10

43

22

1

1

1

i

|

249

234

221

188

206

14

232

207

240

251

223

234

253

243

247

255

267

225

223

228

222

227

101

183

209

140

16

250

253

192

241

81

99

77

|

i 

!

J

i

i

i

9

4

3

!"

!

1 

|

i

i 

1

13

5

13

28

24

8

44

51

40

32

5

1 5

20

6

1

16

6

1

12

20

7

10

26

10

28

20

1

1

2

6

2

8

3

3

4

6

6

j

1

3

1

1

6

1

1

1

2

4

6

1

Bucalla cfhamal

1

1

1

1

4

1

1

2

1

4

6

2

2

2

1

2

1

1

1

2

2

1 |

1

1

3

2

1

5

3

6

1

2

1

3

1

2

22

8

2

80

1

2

5

10

|

4

1

9

5

8

5

3

2

2

4

6

3

1

12

9

9

9

2

2

4

2

2

1

2

2

2

5

2

4

1

1

1

2

2

1

1

j

1

1

Guttullna lactaa

1

1

2

22

7

2

1

1

1

2

10

5

1

3

4

1

1

1

3

1

5

|

I

5

3

8

1

5

3

1

1

Cronin, Ishman, Wagner, Cutter
Appendix 2: Species Census data of Foraminifera on the Virginia Continental Shelf, Fall 

Q

CO

11/6/96

11/6/96

11/6/96

11/6/96

11/6/96

11/6/96

11/6/96

11/6/96

11/6/96

10/22/96

10/22/96

10/22/96

10/22/96

10/22/96

10/22/96

10/22/96

10/22/96

10/21/96

10/21/96

10/21/96

10/21/96

10/21/96

10/21/96

10/21/96

10/21/96

176

174

185

194

181

361

372

332

377

205

204

106

104

66

60

213

31

263

229

209

64

264

46

234

13

8

75.898

75.907

75.901

75.903

75.917

75.897

75.892

75.896

75.872

75.868

75.872

75.907

75.915

75.912

75.929

75.875

75.934

75.869

75.848

75.851

75.917

75.865

75.913

75.869

75.93

Longitude

36.816

36.816

36.812

36.808

36.812

36.738

36.733

36.75

36.733

36.908

36.908

36.843

36.843

36.858

36.862

36.905

36.874

36.887

36.902

36.908

36.857

36.887

36.867

36.898

36.878

Latitude

Elphldum axcavatum davata

5

22

13

31

5

13

10

16

33

41

20

25

17

11

32

11

1

26

15

11

25

54

46

24

28

275

225

272

Elphldum axcavatum aalaayanala

247

261

265

189

182

219

239

248

259

229

237

273

238

40

225

223

217

231

167

120

199

210

Elphldum axcavatum axcavata

8

14

5

12

3

23

5

43

29

23

18

10

6

3

14

13

9

38

77

9

12

13

27

1

1

5

4

2

3

5

4

1

1

1

2

2

9

1

1

15

9

11

4

9

lawatuo anaong

2

2

4

J

1

2

1

2

5

2

4

2

2

1

j

i

i 

1

t

2

7

5

6

1

1

4

3

5

1

3

2

3

2

5

Quinqualocullna aamlnula

6

2

6

2

2

1

6

1

5

4

4

3

4

3

1

1

i

1

1

2

2

1

2

1

2

2

5

1

6

1

6

3

4

1

1

5

1

,

1

1

1

1

eotoei aunntmo

1

3

1

1

1

1

2

1

1

OulnqualocuUnaJugoaa

1

1

1

,

5

2

2

3

6

9

4

1

2

1

1

1

1

,

1

2

3

2

1

6

4

1

Eggnlla advana

1

3

1

Cronin, Ishman, Wagner, Cutter
Appendix 3: Species Census data of Ostracoda on the Virginia Continental Shelf, Spring and Fall 1996

Q

CO 

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

May-96

May-96

May-96

May-96

May-96

May-96

May-96

May-96

May-96

May-96

8

307

308

318

316

336

347

360

361

372

332

342

353

365

377

390

264

263

246

213

204

229

234

201

205

229

106

115

137

181

183

194

185

174

36.843

36.839

36.832

36.812

36.812

36.808

36.812

36.816

36.761

36.761

36.758

36.758

36.75

36.746

36.742

36.738

36.733

36.75

36.746

36.742

36.738

36.733

36.73

36.887

36.887

36.894

36.905

36.908

36.902

36.898

36.908

36.908

36.902

Latitude

75.907

75.908

75.9

75.917

75.908

75.903

75.901

75.907

75.88

75.875

75.874

75.883

75.881

75.874

75.861

75.897

75.892

75.896

75.893

75.89

75.881

75.872

75.854

75.865

75.869

75.858

75.875

75.872

75.848

75.869

75.885

75.868

75.848

Longitude

1

Actino. captionla \

3

2

2

Benaon. ap. A\

5

1 1

3

1

1

Benaon.whttel |

1

1

e

Campylocythere laeva |

1

Cytherura howel \

Cytheromorpha wameri |

2

|

2

6

1

| |

1

1

4

2

1

1

3

1

CuahmanUea aemlnuda

2

1

2

2

1

2

1

2

Eucythere decllvia

2

1

Hemlcytherura

2

1

2

3

1

I

1

1

1

1

3

1

Hullnga.ruglpuatuloaa

1

Hullngalna ap.

1

1

1

1

1

3

1

1

1

a 

4

1

1

1

*

1

4

6

2

28

s

12

2

5

6

2

Mlcrocytherura ap. A

10

2

1

3

1

1

Mlcrocytherura ap. B

1

Muellerlna ohmerti

1

1

Paradox, dellcata

1

7

1

Peratocytherldea bradyl

1

5

3

5

8

5

Cronin, Ishman, Wagner, Cutter
Appendix 3: Species Census data of Ostracoda on the Virginia Continental Shelf, Spring and Fall 1996

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Oct-96

Jun-97

Jun-97

Jun-97

Jun-97

Jun-97

Jun-97

Jun-97

Jun-97

Jun-97

Jun-97

Jun-96

Jun-97

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Jun-96

Nov-96

Nov-96

Nov-96

Nov-96

Nov-96

Nov-96

Nov-96

Nov-96

Nov-96

361

372

332

377

263

229

209

205

204

106

104

66

64

60

55

52

46

31

24

13

255

246

234

209

205

201

104

13

169

13

24

61

50

49

66

104

176

174

185

194

181

36.908

36.908

36.908

36.843

36.843

36.858

36.857

36.862

36.863

36.862

36.867

36.874

36.874

36.878

36.891

36.894

36.898

36.908

36.908

36.908

36.908

36.843

36.878

36.878

36.8195

36.878

36.878

36.874

36.858

36.867

36.867

36.858

36.843

36.816

36.816

36.812

36.808

36.812

36.738

36.733

36.75

36.733

36.887

36.902

75.907

75.915

75.912

75.917

75.929

75.917

75.928

75.913

75.934

75.923

75.93

75.863

75.858

75.869

75.851

75.868

75.885

75.884

75.915

75.915

75.9304

75.901

75.93

75.93

75.923

75.932

75.916

75.902

75.912

75.915

75.898

75.907

75.901

75.903

75.917

75.897

75.892

75.896

75.872

75.869

75.848

75.851

75.868

75.872

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

2

1

1

2

1

1

1

1

1

2

1

1

1

2

6

4

1

1

5

3

1

2

3

2

2

2

5

1

2

1

1

1

1

1

1

1

4

1

2

2

1

1

1

1

1

1

3

1

1

1

4

1

1

1

1

1

2

2

3

1

1

2

1

1

3

2

1

2

1

1

1

1

1

1

1

1

2

1

1

1

1

1

1

1

1

1

1

1

3

6

1

1

2

4

1

4

5

6

2

3

5

1

1

1

Cronin, Ishman, Wagner, Cutter