RICHARD EDWARD YOU The Systematics r and Areal Distribution of Pelagic Cephalopods from the Seas off Southern California SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY NUMBER 97 SERIAL PUBLICATIONS OF THE SMITHSONIAN INSTITUTION The emphasis upon publications as a means of diffusing knowledge was expressed by the first Secretary of the Smithsonian Institution. In his formal plan for the Insti- tution, Joseph Henry articulated a program that included the following statement: "It is proposed to publish a series of reports, giving an account of the new discoveries in science, and of the changes made from year to year in all branches of knowledge." This keynote of basic research has been adhered to over the years in the issuance of thousands of titles in serial publications under the Smithsonian imprint, com- mencing with Smithsonian Contributions to Knowledge in 1848 and continuing with the following active series: Smithsonian Annals of Flight Smithsonian Contributions to Anthropology Smithsonian Contributions to Astrophysics Smithsonian Contributions to Botany Smithsonian Contributions to the Earth Sciences Smithsonian Contributions to Paleobiology Smithsonian Contributions to Zoology Smithsonian Studies in History and Technology In these series, the Institution publishes original articles and monographs dealing with the research and collections of its several museums and offices and of professional colleagues at other institutions of learning. These papers report newly acquired facts, synoptic interpretations of data, or original theory in specialized fields. These pub- lications are distributed by mailing lists to libraries, laboratories, and other interested institutions and specialists throughout the world. Individual copies may be obtained from the Smithsonian Institution Press as long as stocks are available. S. DILLON RIPLEY Secretary Smithsonian Institution INTERNATIONAL MOK YEAR • 1*72 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY NUMBER 97 Richard Edward Young The SyStematlCS and Areal Distribution of Pelagic Cephalopods from the Seas off Southern California SMITHSONIAN INSTITUTION PRESS CITY OF WASHINGTON 1972 ABSTRACT Young, Richard Edward. The Systematics and Areal Distribution of Pelagic Cephal- opods from the Seas off Southern California. Smithsonian Contributions to Zoology, number 97, 159 pages, 15 figures, 38 plates, 1972.—The mid-water cephalopods from off the coast of southern California and adjacent areas are described and their areal distribution is discussed. Forty-two species of pelagic cephalopods are now known from this area including ten new species. Off southern California the fauna is part of the transitional and subarctic fauna to the north, while primarily tropical species are found off northern Baja California. Official publication date is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Smithsonian Year. UNITED STATES GOVERNMENT PRINTING OFFICE WASHINGTON : 1972 For sale by the Superintendent of Documents. U.S. Government Printing Office Washington, D.C. 20402 - Price $2.00 (paper cover) Contents Page Introduction 1 Material and Methods 1 Acknowledgments 3 Description of Study Area 4 Zoogeography 5 Material Examined 7 Key to the Species Described in this Report 11 Systematics 13 Records of Additional Pelagic Species from off Southern California 98 Checklist of Cephalopods Definitely Known to Occur in Southern Cali- fornian or Neighboring Waters 99 Summary 100 Systematics 100 Distribution 101 Literature Cited 101 Appendix 1 106 Appendix 2 107 Plates 109 Richard Edward Young The SyStematlCS and Areal Distribution of Pelagic Cephalopods from the Seas off Southern California Introduction gathered by G. L. Voss at the University of Miami's Institute of Marine and Atmospheric Sciences. The The pelagic cephalopod fauna of the eastern North University of Southern California trawling pro- Pacific is poorly known. The single major paper gram initially studied the waters over the most acces- treating cephalopod systematics of this area (Berry sible inshore basin, the San Pedro Basin, which lies 1912b) dealt with only a small portion of the pelagic between the mainland and Santa Catalina Island. species. Material for this study was collected by the The program subsequently was extended to in- University of Southern California over a six-year clude the area of the Santa Caltalina Basin to span from the fall of 1960 to the fall of 1966. During the west of Santa Catalina Island. The most this period, 445 mid-water tows were taken with an intensive sampling (over 200 stations) has oc- Isaacs-Kidd mid-water trawl. This represents an esti- curred in this area. While never completely aban- mated 911 hours of "fishing" at discrete depths from doning these two basins, the program was extended to the surface to about 1200 meters. This program include San Nicolas Basin, San Clemente Basin, the yielded over 5,000 specimens of pelagic cephalopods waters just west of the continental slope, and the belonging to 40 species of which 33 are described in waters to the south as far as the vicinity of Guada- this report. lupe Island. The total area studied is well within a The present paper attempts to delineate the pelagic region extending from 28°N to 34°N. While the cephalopod fauna occurring in the waters off south- region sampled is rather small, it lies within a transi- ern California and to discuss the zoogeographic rela- tional faunal region and, as a result, distinct differ- tionships of this fauna. Subsequent papers will treat ences were noted in the species composition between the vertical and seasonal distribution of the most the northern and southern ends of this area. To abundant species. demonstrate such geographic differences, I have di- vided the area of study into seven zones (Figure 2) Materials and Methods so that each includes a major area of sampling. In this paper, the following abbreviations are used: Specimens were collected with an Isaacs-Kidd mid- Sta. no. number of station where specimen was water trawl with a mouth 10 feet in diameter. The captured net was operated from the University of Southern M.L. mantle length California's R/V VELERO IV. Comparative ma- M.W. mantle width terial was available from the large collections P.L. pen length Richard Edward Young, Department of Oceanography, P.W. greatest width of pen University of Hawaii, Honolulu, Hawaii 96822. F.L. fin length SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY 34° FIGURE 1.—Localities of trawling stations. Dots correspond to the midpoints of the trawl- ing transects. 120° 116° H.W. head width A.C. Hooks I-IV number of hooks on the indicated H.L. head length measured from the anterior end arm of the nuchal cartilage of the base of arms I Sucker D. diameter of largest arm sucker Tail L. tail length + accurate count or measurement greater than Arm L. I length of arm I measured from the arm given figure due to damaged arm. base, between arms I (where the muscular portion Club L. length of tentacular club of the arms join) to the arm tip Club H. number of hooks on club Arm L. II length of arm II measured from the arm Club H. F. club hook formula (number of hooks in base between arms II and III to the arm tip the dorsal medial row over the number in the ven- Arm L. Ill length of arm III measured from the tral medial row) arm base between arms II and III to the arm tip Club S. number of suckers on club Arm L. IV length of arm IV measured from the Club S. D. diameter (long axis) of largest club arm base between arms IV to the arm tip sucker A.C. I-IV arm count (Total number of suckers Carp. S. number of suckers in carpal cluster and/or hooks on the indicated arm) Carp. K. number of knobs in carpal cluster l/i A.C. I-IV total number of suckers and/or hooks Carp. F. carpal formula (number of carpal knobs on the proximal 50 percent of the arm length of over the number of carpal suckers) the indicated arm measured from the basal sucker Dact. S. number of suckers on the dactylus of the A.C. Dist. S. I-IV number of suckers distal to arm club hooks on the indicated arm Dact. T.S. number of suckers in the sucker pad at A.C. Prox. S. I-IV number of suckers proximal to the tip of the dactylus arm hooks on the indicated arm Tent. L. tentacle length NUMBER 9 7 FIGURE 2.—Breakdown of area studied into zones corresponding to major areas of sam- pling. 28° 120° 118° Stalk S. number of suckers on the tentacular stalk sides have been averaged to give single figures. Meas- D.S.S. number of suckers in the dorsal row on the urements are in mm and have been rounded to the tentacular stalk nearest whole number in most cases. V.S.S. number of suckers in the ventral row on the tentacular stalk Acknowledgments M.S.S. number of suckers in median portion of ten- tacular stalk I am indebted to many people who assisted me in R. right the present work. J. S. Savage, J. S. Garth, R. L. left Lavenberg, D. Bright, and R. Given associated Tub. L. length of cartilagenous strip bearing tuber- with the University of Southern California pro- cules vided specimens and data. F. Hochberg kindly Tubercles number of cartilagenous tubercules at supplied specimens taken by the R/V SWAN. G. funnel-mantle fusion Y. Hendrix of the University of Miami provided Gill L. gill length a considerable amount of help in sorting and car- G.C. gill count (total number of primary gill ing for the collection and in making preliminary lamellae) identifications during the early stages of this work. Gill W. gill width Diane McGinnis helped with sorting when time Lam. L. length of longest lamella was becoming a critical factor.