Proceedings of the United States National Museum
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PROCEEDINGS OF THE UNITED STATES NATIONAL MUSEUM issued M$(v d 0.?^ h the SMITHSONIAN INSTITUTION U. S. NATIONAL MUSEUM Vol. 99 Washington: 1949 No. 3235 A FURTHER CONTRIBUTION TO THE ICHTHYOLOGY OF VENEZUELA By Leonard P. Schultz This paper is the third report on the collections made by me in Venezuela during 1942 and those made by the U. S. S. Niagara in the Gulf of Venezuela during 1924 and 1925. Other miscellaneous small collections were included when they were found in the National Museum, as were others kindly lent for study and report. To the following I express my sincere gratitude for their kindness and coop- eration: Dr. Reeve M. Bailey, Museum of Zoology, University of Michigan, lent some of the Bond Venezuelan collections made in 1938-40. Dr. Karl P. Schmidt and Marion Grey, Chicago Natural History Museum, lent the W. H. Osgood specimens taken in the Maracaibo Basin. Dr. William Beebe, New York Zoological Society, lent his collections from the vicinity of Caripito. Isaac Ginsburg, U. S. Fish and WildUfe Service, identified all the specimens of Gobiidae and Eleotridae in the above-mentioned collections. Dr. Samuel F. Hildebrand, of the same Service, while working up his collections of marine fishes from Panama, identified several species of Venezuelan marine fishes and aided in many other ways. Luis Rene Rivas very kindly checked the spelling of the Spanish names of fishes and of the localities. My interest in Venezuelan ichthyology began in the winter of 1941- 42 when, at the invitation of Dr. GuiUermo Zuloaga, assistant chief of explorations, Creole Petroleum Corp., Caracas, I undertook to study 802207—i9 1 1 SEP 3 1952 2 PROCEEDINGS OF THE NATIONAL MUSEUM vol.99 and make collections of fishes in the Maracaibo Basm of Venezuela. This work continued from February through May of 1942. I pro- ceeded to Venezuela under the auspices of the Smithsonian Institution and of the United States Department of State and was a guest there of the then Standard Oil Co. of Venezuela, and of the Lago Petroleum Corp., Lago de Maracaibo. To the officials of these companies I again express my gratitude for their full cooperation. My first report on these collections was entitled "The Catfishes of Venezuela, with Descriptions of Thirty-eight New Forms," published February 11, 1944, in the Proceedings of the United States National Aluseum, volume 94, pp. 173-338, 5 figs., 14 pis. In this report is given an itinerary of my travels in Venezuela along with a Ust of col- lecting stations. The second report, "The Fishes of the Family Characinidae from Venezuela, with Descriptions of Seventeen New Forms/' was published September 6, 1944, in the same Proceedings, volume 95, pp. 235-367, 27 figs. A summary of my Venezuelan collections during 1942 reveals that the largest number of species taken in one locality was 45 from the Rio Negro. The next largest collection numbered 35 from the Rio San Juan (Motatdn system), 33 from the Rio San Pedro, and 33 from the Rio Socuy. In the stream systems where fairly representative collections were made the following number of species were preserved: Rio Motatdn, 54; Rio Negro, 45; Rio Palmar, 41; Rio Socuy, 33; Rio Ap6n. 31; Rio Machango, 31; and Rio Chama, 10. There were 56 species from Lago de Maracaibo and along the coast of Gulf of Vene- zuela to Cafio de Sagua. Altogether my collections contained 140 species from the Maracaibo-Gulf of Venezuela Basins; 25 from Rio Gudrico and Rio Torbes; 1 from Rio Tuy system; and 3 species com- mon to the first two basins, a total of 169 species and subspecies that I collected. The present report is not intended to be comprehensive in scope, since there are not yet sufficient collections of fishes from Venezuela to justify the writing of a descriptive catalog. It is rather a report on several collections of Venezuelan fishes, with descriptions of new species, and represents only the beginning in the study of the fish fauna of Venezuela. It is highly desirable that much more extensive collections be made in all the stream systems and lake basins of the country. Unless otherwise indicated all collections were made in 1942 by L. P. Schultz in the Maracaibo Basin. Abbreviations used to indicate museum catalog numbers are as follows: A. N. S. P. = Academy of Natural Sciences of Philadelphia. C. N. H. M. = Chicago Natural History Museum. U. M. M. Z. = University of Michigan Museum of Zoology. U. S. N. M. = United States National Museum. ICHTHYOLOGY OF VENEZTJELA—SCHULTZ 3 GEOGRAPHY AND CLIMATE OF THE MARACAIBO BASIN Lago de Maracaibo has an average depth of about 100 feet (maxi- mum 34 meters, or 11 iK feet) and a soft muddy bottom. From its southern end to the beginning of the channel at Punta de Pahnas, south of the city of Maracaibo, it is 154.5 kilometers, or 95.8 miles, long; the length of the channel from Punta de Palmas to Punta Vigia at entrance into El Tablazo is about 39% kilometers, or 24.3 miles; and from Punta Vigia across El Tablazo to the entrance into the Gulf of Venezuela at Castillo de San Carlos is 20.75 kilometers, or about 12.9 miles, making a total length from the Gulf of Venezuela to the southern end of the lake of 214.9 kilometers, or about 133.25 miles. The greatest width of the lake is about 121 kilometers, or 75 miles. The long axis of the lake is almost directly north-south. High mountain ranges enclose the T^Iaracaibo Basin on all sides except the north. The Sierra de Perija forms the western divide, whereas the Cordillera Oriental occurs at the southwestern side, and along the southern and southeastern side the lofty Cordillera de Los Andes, with Pico Bolivar reaching to a height of 5,005 meters. Another range of high hills and mountains forms the eastern rim of the basin. The northern end of the l\Iaracaibo Basin is semidesert, contrasting sharply with the tropical jungle at the southwestern and southern ends, where the rainfall is very great along the eastern slopes of the Cordil- leras de Perijd and Oriental even during the dry season. During 1941 the Maracaibo Nautical School recorded the following monthly average temperatures and total monthly rainfall at Mara- caibo, as published February 14, 1942, in the Maracaibo Herald: January, 81° F., 4 mm.; February, 83° F., 6 mm.; March, 82° F., no rainfall; April, 84° F., 16 mm.; May, 85° F., 144 mm.; June, 85° F., 85° 1 1 mm. ; July, 85° F., 9 mm. ; August, 85° F., 3 mm. ; September, F., 38 mm.; October, 83° F., 26 mm.; November, 84° F., 68 mm.; De- cember, 83° F., 5 mm. The rainfall thus totals 330 mm., or 13 inches. The average monthly rainfall for the eastern shore at LaguniUas is given below for a period of 14 years (1928-1941), from information furnished by the Lago Petroleum Corp. These records are in inches, with minima and maxima in parentheses. January, 0.22 (0.00 to 1.33); February, 0.26 (0.00 to 1.08); March, 0.69 (0.00 to 2.09); April, 1.59 (0.11 to 5.41); May, 4.47 (1.49 to 9.21); June, 3.20 (1.07 to 7.72); July, 3.81 (0.87 to 11.71); August, 4.05 (0.76 to 8.91); September, 4.89 (0.94 to 11.90); October, 6.21 (2.62 to 11.53); November, 3.52 (0.45 to 8.78); December, 0.80 (0.00 to 1.78). Total average rainfall 33.98 inches, with a minimum of 18.40 in 1939 and a maximum of 51.01 in 1933. These data indicate the increase in amount of rainfall southward in the Maracaibo Basin. Undoubtedly the heaviest rain- fall occurs at the southwestern corner of the Basin where the jungle is 4 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 99 heaviest and where the big rivers empty large quantities of muddy water into the lake. During the dry season from December through March the trade winds are strongest, blowing from the north and northeast through the channel and lengthwise across the lake, becommg strongest in the afternoon, late evening, or early part of the night. The surface water of the lake apparently has a counterclockwise rotation in the southern two-thirds of the lake. The specific gravity of the water was taken by means of a saU- nometor, and the following readings were recorded: Gulf of Venezuela, 1.021 at mouth of Cafio de Sagua on incoming tide; El Tablazo and at Maracaibo Yacht Club, 1.006; Lago de Maracaibo, 2 km. off Lagunillas, 1.004; and at southwestern end of the lake 2 Ian. off Rio Concha, 1.002. The turbidity of the water may increase its specific gravity a httle at the southern end of the lake. Undoubtedly the deeper waters of this lake are salty. FISHERIES OF THE GULF OF VENEZUELA-MARACAIBO BASIN The fishes of the Gulf of Venezuela and Lago de Maracaibo are almost untouched commercially as compared with the great fisheries of the North Sea and those of the Atlantic and Pacific coasts of North America. I believe the fisheries of Venezuela cannot be greatly developed until more modern fishing equipment, including quick- freezing refrigeration and power fishing boats with refrigeration equipment, are used extensively. Such equipment would permit fishermen to go farther, stay out longer, and still be able to bring back desirable fishes to the market without deterioration and spoilage.