DISTRIBUTION OF SIPHONOPHORES IN THE REGIONS 

 ADJACENT TO THE SUEZ AND PANAMA CANALS 



Angeles Alvarino^ 



ABSTRACT 



These studies are based on the material collected by Israeli cruises in the eastern Mediterranean 

 and the Red Sea (Gulf of Elat), and by Scripps Institution of Oceanography Expeditions in the 

 Caribbean and the Pacific regions adjacent to the Panama Canal. Published information on the 

 distribution of siphonophores in those areas and in adjacent regions is included. Distributional 

 tables and maps are also included. 



The eastern Mediterranean collections encompass 21 species of siphonophores. Most of these 

 species have been previously recorded in the western Mediterranean. Eudoxia russelli (eudoxid 

 of Chelophyes appendiculata), Sulculeolaria angusta, and S. chuni have not been previously 

 observed in any Mediterranean region. New records for the eastern Mediterrranean are: Ch. 

 contorta, Diphyes bojani. D. dispar. Lensia campanella, L. meteori, L. subtilis, S. quadrivalvis, 

 S. turgida. Rosacea plicata, Physophora hydrostatica , and Apolemia uvaria. Few sjjecies previously 

 observed in the Mediterranean were not present in the collections here analyzed. 



Fifteen species of siphonophores appeared in the material from the Gulf of Elat. New records 

 for the Red Sea are Ch. appendiculata, E. russelli, Diphyopsis mitra. The other species 

 present iCh. contorta, Diphyes dispar, L. subtilis, S. chuni, S. quadrivalvis, Abylopsis 

 eschscholtzi, A. tetragona, Enneagonum hyalinum, Cordagalma cordiformis, Agalma 

 elegans, and A. okeni) have been previously observed in the Red Sea. 



New records at both sides of the Suez Canal which could be considered indicative of 

 migration along this waterway are: Ch. appendiculata (Mediterranean to the Red Sea), and 

 S. chuni (Red Sea to the Mediterranean). However, the species are cosmopolitan in distribution, 

 and the source of the populations in the regions adjacent to the Suez Canal may be in the 

 adjacent oceanic regions. 



Thirty species of siphonophores were observed in the Caribbean and Pacific regions adjacent 

 to the Panama Canal. Most of the species are new records for those regions. Twenty one more 

 species, not present in the collections here analyzed, had been previously recorded at either or in 

 both the Caribbean, Gulf of Mexico and/or in regions of the Pacific adjacent to the area surveyed. 



Particular attention is devoted to the distribution of closely related pairs of allopatric species, 

 Muggiaea atlantica-M. kochi, and Ch. appendiculata-Ch. contorta. Muggiaea kochi (neritic species) 

 and Ch. appendiculata inhabit the Caribbean, Gulf of Mexico and adjacent regions of the 

 western tropical Atlantic. Muggiaea atlantica (neritic species) and Ch. contorta inhabit the 

 Pacific regions off Mexico and Central America. However, few specimens of Ch. contorta 

 and M. atlantica were also observed in the Caribbean at locations near the opening of the Panama 

 Canal, and specimens of Ch. appendiculata and M. kochi occurred at locations in the Pacific close 

 to the Panama Canal. This distributional incidence may suggest that migration or artificial 

 transport is taking place via the Panama Canal. It is also indicated that few specimens of 

 L. challengeri (Indo-Pacific species) were observed near the opening of the Panama Canal in 

 the Caribbean, 



New data have been published on the siphono- 

 phores of the regions adjacent to the Suez Canal 

 (eastern Mediterranean and the Red Sea), as well 

 as for the regions adjacent to the Panama Canal 

 (western Caribbean and the Central American 

 Pacific). Bigelow and Sears (1937) included data 

 on the distribution of the siphonophores in the 

 eastern Mediterranean, and Lakkis ( 1971) on the 



'Southwest Fisheries Center, National Marine Fisheries 

 Service, NOAA, P. O. Box 271, La Jolla, CA 92037. 



Manuscript accepted September 1973. 

 FISHERY BULLETIN: VOL. 72. NO. 2. 1974. 



Lebanese region. Schneider (1898), Totton (1954), 

 and Halim (1969) presented information on the 

 siphonophores of the Red Sea. Bigelow (1911) 

 analyzed the siphonophores of the eastern tropical 

 Pacific, which included few locations in the 

 regions here surveyed; Alvariho (1968, 1972) 

 studied the siphonophores of the tropico-equa- 

 torial oceanic regions, and Alvarino (1971) 

 covered the Central American Pacific including 

 also a compilation of distributional data for the 

 world oceans. 



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