Date Awarded


Document Type


Degree Name

Doctor of Philosophy (Ph.D.)


Virginia Institute of Marine Science


Willard A. Van Engel

Committee Member

George C. Grant

Committee Member

William G. MacIntyre

Committee Member

William C. Pinschmidt, Jr.

Committee Member

Marvin L. Wass


This dissertation is from the Joint Program Degree from the College of William & Mary and University of Virginia and awarded by the University of Virginia.

Provisional keys to the marine decapod crustacean zoeae of the Chesapeake Bay are presented. These keys provide distinguishing characters for the specific or generic identification of zoeae of 50 decapod species. Also, provisional classification schemes for the different morphological types of antennae and telsons exhibited by Chesapeake Bay brachyuran larvae are given, and the larval stages of each species or genus considered in the keys are briefly described.

The larval development of eight Chesapeake Bay decapod species for which the larvae were previously unknown was studied in detail. All larval stages of ~rides limicola and Libinia dubia and the first zoea of Arenaeus cribrarius are described from laboratory-reared specimens, and four larval stages of Callianassa sp. A (=.Q_. major?), two of Callianassa sp. B (=C. atlantica?), one of Callianassa sp. C, four of Upogebia affinis, and three of Lepidopa websteri (?) are described from specimens taken from the plankton.

Previous studies concerning the effects of temperature and salinity on larval development of Chesapeake Bay decapods are reviewed, and the results of an experiment to determine the effects of temperature and salinity on larval development of Palaemonetes vulgaris are presented • .!:• vulgaris larvae were reared in the laboratory in a factorial experiment employing three temperatures (20, 25 and 30 C) and six salinities (5, 10, 15, 20, 25 and 30 0/00). Considering survival, rate of development, and number of instars, optimal conditions for larval development were found to occur at a temperature of about 25 C in salinities of 10 to 30 0/00. Surface and bottom plankton samples taken with a Clarke-Bumpus Quantitative Plankton Sampler at monthly intervals over a two-year period were made available to me by Dr. V. G. Burrell, Jr. These samples were collected at 12 stations spread over a distance of about 80 miles from freshwater in the Pamunkey River, through the meso- and polyhaline York River, to euhaline conditions at the mouth of Chesapeake Bay. Some additional samples were collected with paired BCF Bongo samplers. Planktonic stages representing 37 species and genera of decapods were identified in these zooplankton collections.

Decapod larvae were numerous throughout the estuary during the summer. However, larvae of Crangon septemspinosa were abundant in the bay from late winter throughout the spring, and peak numbers were generally of the same order of magnitude as total concentrations of larvae of the other species at the bay stations during summer.



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