Bulletin of the United States Fish Commission
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THE DECAPOD CRUSTACEANS OF BEAUFORT, N. C.~ AND THE SURROUNDING REGION By W. P. Hay and C. A. Shore Contribution from the United States Fisheries Biological Station. Beaufort. N. C. Blank page retained for pagination THE DECAPOD CRUSTACEANS OF BEAUFORT, N. C., AND THE SURROUNDING REGION. By W. P.RAY and C. A. SHORE. Contribution from the United States Fisheries Biological Station. Beaufort, N. C. ,;f INTRODUCTION. The following report on the decapod crustaceans of the region surrounding Beaufort, N. C., was begun by the junior author in 1904, while a student in the University of North Carolina, and was worked on actively for three years. During that time the crustacean material which had accumulated at the United States fisheries laboratory was studied and identified, much collecting was done and descriptions of most of the species known to occur in the region were prepared for publication. An extensive series of photo graphs was also made for the purpose of illustrating the paper. At this point other duties intervened and made it necessary to permanentlyabandon all hope of completing the report. In 1912 the senior author took up the work. It was hoped at first to bring the paper to an early conclusion, but it soon became evident that several seasons' work would be required to produce a satisfactory result. The nomenclature and synonymy of the species already described had to be brought up to date, the rather extensive coIIections of five or six years had to be worked over, and numerous additional descrip tions and photographs had to be prepared. As the work progressed it became clearly evident that the needs of the student of crustaceans would be best served by the prepara tion of entirely new and uniform descriptions of all the species. Although this involved the rewriting of all the descriptions of the junior author and the preparation of a new series of photographs, the task was undertaken and pushed forward as rapidly as other duties would permit. It is now brought to a conclusion with the belief that future collecting will add but few species to the list. The growth of our knowledge of the crustacean fauna of the Beaufort region has been slow and extends over many years. The first collector, of whose work we have a record, was William Stimpson, who visited Beaufort, in company with T. N. Gill, in 1860. In his brief account of this trip a he gives a list of 38 species of decapod crusta ceans which he had collected. In 1871 Elliott Coues, at 'that time an Army surgeon, stationed at Fort Macon, published the second of his" Notes on the fauna of Fort Macon, N. C., and vicinity (No. 2)"b which included a list of 27 species of decapods, a Amer. Jour. Sciences and Arts, series 2, vol, XXIX, p, 44.-445. 1860. b Prec. Acad. Nat. Sci. Phil., vol. xxm, p. 1.0-124. 1871. 371 372 BULLETIN OF THE BUREAU OF FISHERIES. 8 of which were additions to Stimpson's list. Seven years later Coues and Yarrow, in the fifth installment of "Notes on the fauna of Fort Macon, N. C., and vicinity (No. 5)"a gave a short list of 6 species, 2 of which had not appeared in any previous list. An appendix to the same paper, by J. S. Kingsley, entitled "A list of the decapod crus taceans of the Atlantic coast whose range embraces Fort Macon," b included 63 species, of which 51 were definitely credited to Beaufort or Fort Macon and 3 were additions to the fauna. A year later the same author published a paper under the title, "On a collection of crustaceans from Virginia, North Carolina, and Florida, with a revision of the genera of Crangonidee and Paleemonidse" C in which he mentions 36 species as having come from Beaufort or Fort Macon. Of these, 8 were new records. 'The collection which was the subject of Kingsley's report had been made by Prof. H. E. Webster, of Union College. It was later transferred, in part at least, to the United States National Museum and supplied the types of Lepidopa websteri Benedict and Pinnixa cristata Rathbun, both of which were collected near Beaufort. During the years that Johns Hopkins University maintained its seaside laboratory at Beaufort, the crustaceans were studied by Dr. Brooks and a number of his students. A great deal was added to the knowledge of the habits and development of some of the species, but only one or two new ones were added to the fauna.d 'The manuscript of the junior author included 87 species, but he omitted 8 which had been listed by the writers already mentioned. His additions to the fauna were 33 species, making a total of 95 species for the Beaufort region. The careful and systematic survey of the offshore fishing banks by the steamer Fisk Hawk during the summers of 1914 and 1915, energetic shore and shallow water collecting by parties from the laboratory and the inclusion of the fresh-water species of the region have enabled the senior author to add 57 species to those already known, and the detection by Dr. Mary J. Rathbun of a hitherto unknown species of Parapinnixa brings the total to 153. 'The status of some of these species may justly be questioned, but it has been thought advisable to include all that have been reported from the region and all which, from what is known of their habits and distribution, are reasonably certain, sooner or later, to fall into the hands of the collector. There are also included several species which are perhaps, strictly speaking, deep-water forms ranging well beyond the 50-fathom line. In nearly all cases, however, they are represented in our collections by specimens from shallower water or are known to enter shallower water in localities not far to the north or to the south. The report thus becomes virtually a descriptive list of the decapod crustaceans of the Middle Atlantic coast, and, to a large measure, fills the gap between the various lists of New England, New York, and New Jersey crustaceans, and the Porto Rican fauna described by Dr. Mary J. Rathbun. It includes a large proportion of the species whose northern limit of distribution has been supposed to be in the neigh borhood of Charleston, S. C., together with many that, up to the present, have not been known north of Florida or the West Indies. a Proc. Acad. Nat Sci. Phil., vol. xxx, p. '97-315. 1878. b Ibid., p. 316-330. C Proc. Acad. Nat. Sci. Phll., vol. XXXI, p. 38r4'7, pl. '4. 1879. cfStenotnu hisPidus, the larval fonn of which was reported by Brooks and Herrick (Mem. Nat. Acad. Sei., v, 33r35') is not included in the present paper. The adult has not been collected north 01the Bahamas. DECAPOD CRUSTACEANS OF THE BEAUFORT, N. C., REGION. 373 The general aspect of the decapod fauna of the Beaufort region is subtropical. Un questionably the great influx of species have been from the south, and the comparatively few northern ones that occur are evidently at a disadvantage. The Gulf Stream sweeping up along the coast at no great distance from the shore has doubtless been the route by which numerous crustaceans, often in the larval stages, have come northward. Some of these have been able to establish themselves while others ate more or less regularly replaced by new individuals as the old ones are killed during the colder months of the year. The offshore fishing banks a offer peculiarly favorable conditions for the life of these tropical species of crustaceans, and of fishes, echinoderms, coelenterates, and sponges as well, and have Yielded some 30 species of decapods which have rarely, if ever, been taken closer to the shore. The Gulf Stream and the prevailing south and southeast winds bring to the region, and often into the harbor, great quantities of drifting Sargassum among which large num bers of the smaller pelagic crabs and shrimps have taken shelter. In nearly all cases, the females of these species are laden with eggs, but it is probable that few if any of these survive the journey into the shallower and quieter waters along the coast. Some of the pelagic species, however. are so constant in their occurrence and their larval forms are so frequently met with that it is evident that they breed at no great distance from, if not within, the region. For the truly local fauna, comprising the species that are firmly established and which can readily be obtained by ordinary methods of collecting, the shallow waters of the sounds and Beaufort Harbor, with their broad expanses of sand and mud flats, and the salt marshes which extend for miles along their margins offer an ideal home. The shrimps and swimming crabs are found in abundance in the deeper waters or among the eel grass near the marshes. Mud crabs and various burrowing species occuron themuddy bottoms, and myriads of fiddler crabs are to be seen on the mud flats along the margin of the marshes at low tide. In certain parts of the harbor there are areas of shelly bottom of considerable extent, and it is in such places that shrimps of the genus Sicyonia and crabs of the genera Lithadia, Spelceophorus and Heterocrypia occur. On the sandy bottoms the purse crabs (Persephona) and the box crabs (Hepatus) are occasionally found along with numbers of lady crabs (Ovalipes) and blue crabs, both Callimecies sapidu« and C. ornatus. The sand flats, especially if there is an admixture of mud, are good collecting grounds for the burrowing and commensal species such as Upogebia affinis, Polyonyx macrocheles, and thevarious species of Pinnixa.