Alternate Title

Studies on the Larval Development of Rithropanopeus harrisii (Gould) of the Family Xanthidae (Brachyura)

Document Type



Because the early biologists did not see decapod larvae “in the act” of changing from one phase to another due to the fact that they were parts of planktonic collections and their parentage was unknown, each phase was given a generic and specific name of its own. Gurney (1921) did not concur with this practice, but was of the opinion that it is more profitable to assign larvae to definite genera or families, even if the reference proved to be wrong.

The chief difficulty encountered in rearing decapod larvae is the maintenance of a constant supply of suitable living food (Needham, 1959). The early embryonic studies of brachyuran crustaceans did not reveal complete life histories. This was due primarily to the lack of effective culture techniques. Birge (1883) gave no details of his culture methods in the study of the development of Panopeus sayi (Smith). Hyman (1925) gave no account of an attempt to culture larvae of xanthid crabs. In recent years the use of definite diets for the larvae has resulted in a knowledge of complete life histories. Knudsen (1959) used Artemia nauplii in feeding larvae of four xanthid crabs of the California coast. Chamberlain (1961) used various combinations of Artemia nauplii and two species of algae to feed larvae of three xanthid crabs of the North Carolina coast. His best results were with a diet of Artemia alone.

Former studies of brachyuran embryology at the Gulf Coast Research Laboratory were confined to the description of larvae taken in planktonic collections at or near the surface. Advanced larval forms are not found in such collections. It seldom happens that in planktonic material a series of stages of the same larvae is taken which is sufficiently complete to enable the genus to be determined. The remainder must be identified as nearly as possible by reference to published descriptions of larvae whose parentage is known, and such identification must in many cases be very speculative.

Hyman (1925) described a prezoeal, four zoeal and a megalops stage of Neopanope texana sayi (Smith) at Beaufort, North Carolina. Also in his studies is a description of a prezoeal and the first zoeal stage of Eurypanopeus depressus (Smith). Knudsen (1958, 1959, 1960) described culture methods and four zoeal stages and a megalops stage of four species of xanthid crabs from California. Prezoeae were described for two of these species. Chamberlain (1961) described culture methods and four zoeal stages and a megalops of Neopanope texana sayi (Smith) at Duke University Marine Laboratory, Beaufort, North Carolina.

This is a report of a study of the embryonic development of crabs of the family Xanthidae from Biloxi Bay. The larvae were hatched and reared in the laboratory. The work was supported by a Summer Research Grant from the National Science Foundation to the Gulf Coast Research Laboratory.

First Page


Last Page