SMITHSONIAN INSTITUTION MUSEUM O F NATURAL HISTORY For sale by the Superintendent of Documents, U.S. Qovernment Printing Office Washington, D.C. 20402 - Price $1 (paper cover) UNITED STATES NATIONAL MUSEUM BULLETIN 251 Pacific Tunicata of the United States National Museum TAKASI TOKIOKA Seto Marine Biological Laboratory, Japan SMITHSONIAN PRESS WASHINGTON, D.C. 1967 Publications of the United States National Museum The scientific publications of ttie United States National Museum include two series, Proceedings of the United States National Museum and United States National Museum Bulletin. In these series are published original articles and monographs dealing with the collections and work of the Museum and setting forth newly acquired facts in the field of anthropology, biology, geology, history, and technology. Copies of each publication are distributed to libraries and scientific organizations and to specialists and others interested in the various subjects. The Proceedings, begun in 1878, are intended for the publication, in separate form, of shorter papers. These are gathered in volumes, octavo in size, with the publication date of each paper recorded in the table of contents of the volume. In the Bulletin series, the first of which was issued in 1875, appear longer, separate publications consisting of monographs (occasionally in several parts) and volumes in which are collected works on related subjects. Bnlletins are either octavo or quarto in size, depending on the needs of the presentation. Since 1902, papers relating to the botanical collections of the Museum have been published in the Bulletin series under the heading Contributions from the United States National Herbarium. This work forms number 251 of the Bulletin series. Frank A. Taylor Director, United States National Museum U.S. GOVERNMENT PRINTING OFFICE WASHINGTON : 1967 Contents Page Introduction 1 Ascidiacea 22 Order Aplousobranchia 22 Family Synoicidae 22 Family Didemnidae 62 Family Polycitoridae 101 Order Phlebobranchia 133 Family Diazonidae 133 Family Cionidae 133 Family Perophoridae 136 Family Ascidiidae 138 Family Rhodosomatidar' 148 Order Stolidobranchia 151 Family Botryllidae 151 Family Styelidae 162 Family Pyuridae 197 Family Molgulidae 222 Appendicularia 228 Family Oikopleuridae 228 Thaliacea 228 Family Doliolidae 228 Family Salpidae 229 Pyrosomata 230 Family Pyrosomidae 230 Literature cited 232 Index 239 Pacific Tunicata of the United States National Museum Introduction The previously unidentified Tunicata in the U.S. National Museum listed and described herein were collected from various parts of the Pacific, with the exception of the west coasts of North, Central, and South America. Most of the specimens belong to Ascidiacea, but a small number are pelagic tmiicates, including Appendicularia, Thalia- cea, and Pyrosomata. x\s studies of the ascidian fauna in various parts of the Pacific are in progress I think it better, at present, to refrain from writing on general aspects of the ascidian fauna of the Pacific, leaving them for a future paper. Many simple ascidians are identified rather easily, while the identi- fication of compound ascidians is usually very exacting. Even repeat- edly described species might be confused with others, as the range of intraspecific variation is not yet clearly defined for most species. Under these circumstances, it is rather useless to list only the species found in the material. Inevitably accurate descriptions accompanied Avith exact figures for those species must be made. Thus in this paper, most of the compound ascidians are described in detail, while most solitary forms are noted briefly. In descriptions of the branchial sac, the number of stigmata in respective rows and of branchial plications is always given for only one side of the sac. The number of inner longitudinal vessels on respective branchial plications indicates the total number of vessels on both surfaces of each plication. The specimens treated in this paper were examined during my stay at the United States National ]\Iuseum, from February to April 1957, work which was supported with the financial aid of the National Academy of Sciences. I am very grateful to the staff of the United States National Museum, ])articularly the members of the Division of Marine Invertebrates, Dr. Fenner A. Chace and others, for grant- ing me the space in the museum for research and assisting me in obtaining financial aid. Dr. Frederick M. Bayer, at that time of the 1 : ; ; ; ; 2 UNITED STATES NATIONAL MUSEUM BULLETIN 251 Division of Marine Invertebrates, who personally collected a large number of ascidians at Palau during the High Island-Atoll Project, Palau Islands, 1955, by the George Vanderbilt Foundation, and who kindly made all arrangements for me to carry out the present work. Indeed, without his generous help in providing every kind of facility for me, it would have been quite impossible to study so many speci- mens from various parts of the Pacific. I wish to express my hearty thanks to him for his kindness. Included in the material are a number of important collections from the following sources 1. United States Fish Commission Steamer Albatross during her North West Pacific Expedition 1899-1900, the Philippine Expedition 1907-09, and others; 2. The Palau Islands, 1955, by the George Vanderbilt Founda- tion; 3. Various parts of Japan, and presented to the United States National Museum by E. S. Morse, Professor at the Tokyo Imperial University, in exchange 4. From Philippine waters in January 1941, by W. R. Taylor, U.S. National Museum 5. In 1951 at the Gilbert Islands, by P. E. Cloud 6. Dr. S. F. Light, Professor at the University of Amoy, pre- sumably at Amoy, China 7. Ascidians of the university of Hawaii. In addition to these, a few specimens from other localities other than the Pacific were examined and described for comparison with the Pacific species. Following is a list of George Vanderbilt Foundation (hereafter ab- breviated GVF) stations at which tunicates were collected in the Palau Islands in 1955 by R. R. Harry and H. A. Fehlmann of Stanford Uni- versity and F. M. Bayer of the U.S. National Museum. Geographical coordinates of each locality based upon U.S. Navy Hydrographic Office (HO) charts. Numbers of traverses and islands in Iwayama Bay follow the work of Abe (1937) and of Abe, Eguchi, and Hiro (19>,7). Sta. 12. .Tilly. Madalai District, extreme west end of Koror Island, shore at south end of Arakahesan-Madalai causeway, nianffrove shore sradinp; into mud and sand flat: 7°20'36" N., 134°28'13" E. (IIO 6077, 1st ed., 1944). Depth 0-3 ft.; bottom of mud inshore grading into sand offshore; vegetation Enhalus acoroides. Didemnmn {Didemnutn) ternaianvm (Gottschaldt) ; Eudistoma laysani (Sluiter) ; E. pyriforme (Herdman). Sla. 16. 11 July. Madalai District, west end of Koror Island outside of re- taining wall enclosing sandy eelgrass flat. (Outer end of Abe's Traverse III) : 7°20'22" N., 134''28'05" E. (IIO 0077, 1st ed., 1944). Depth 3 ft: bottom sand coral, rock ; "olive green compound tunicate on Enhalus leaves." Didcmnum {Didemmtm) tcrnafanum (Gottschaldt). PACIFIC TUNICATA OF U.S. NATIONAL MUSEUM S Sta. 25. 19 July. Barrier reef S miles nortliwost of Koror Island: 7°24'30" .saiul N., 134°21'20" E. (HO 0102, 1st ed., 11)44). Deptli 3-7 ft. ; bottom and coral heads and dead coral. Ascidia minuta Tokioka ; Botrijlloidvn hjrcum llerdman ; Didcmnum {Didcm- ; 1). (D.) moscleyi num) candidum Savigny D. (D.) mosclcyi (Herdman) ; (Herdman) forma yrunuJalum Tokioka; D. (D.) nekozltu, u. .sp. ; B. {Polysyn- cratoii) sagamiana Tokioka; Eudistoma viridis Tokioka; LcptovUnkles reticu- Polymrpa sp. ; Trididem- latiis (Sluiter) ; Lissocliuum pulvinum (Tokioka) ; num savignii (Herdman). Sta. 23. 21 July. Outer reef at eastern end of Urukthapel Island, about V/i miles north of Pkuiasueh i'oiut: 7°1G'13" N., 134°27'35" E. (HO 0103, 1st ed., 1944) . Depth 2-4 ft., in breakers ; bottom covered with Turhinaria. BotryUoides violacciis margwatus, n. subsp. ; Botryllus tiiheratiis Ritter and Forsyth; PolycHnuin consteUatiiiii Savigny. Sla. 30. 22 July. Iwayama Bay, between south shore of Kaibakku (Island 7^19'12" 134°29'- XXIX) and Kogai Hauto, Auluptagel Island (traverse XI) : N.. 37" E. (HO 0070, 2d ed., 1944). Depth 0-3 ft. ; sand, coral, with vegetation con- sisting mainly of Enhahis and Caiilerpa. ApUdinm lohatum Savigny; Didcmnum (Didcmnum) mosclcyi (Herdman). Sla. 35. 24 July. Peliliu boat channel between Ngargersal and Kongauru I.s- 7°02'.51" 134°- lands approximately 1 mile east of north tip of Peliliu Island : N., 17'42" E. Depth 1-10 ft.; sand, silt, occasional coral; Enhuhia acoroidcs and 2 other ssp. eelgrass ; algae including Caulcrpa. Didcmnum {Didcmnum) nclcoziia, n. sp. Ssa. 53. 31 July. Ngaremdiu area, eastern Urukthapel ; rocky cape west of sand beach Oiratel-ruul : l°l~^'l~j" N., 134°20'51" E. (HO 0103, 1st ed., 1944). Depth 0-7 ft. ; sand, coral, rock. Green in life growing on hydroid. Eudistoma rdridis Tokioka. Sta. 60. 5 August. North shore of Koror Island, west of Ebadul's Pier: 7°20'48" N., 134°28'12" E. (HO 0070, 2d ed., 1944). Depth 0-5 ft; sand flat; occasional coral heads, with Enhalus growing on sandy areas, Sargassum attach- ed to rocks. Found with sponges. Eudistoma sp. aff. anyolaiium (Michaelsen). Sta. 61. 6 August. Seaward reef flat at south end of Ngemelis Island, west side of Palau Archipelago: 7°00'4r)" N., 134°14'40" E. (HO 0073, 2d ed., 1944). Depth 11/^-6 ft. ; coral and sand ; some Enhalus and Ilalimcda in sand patches, on gorgonian. BotryUoides riolaccus Oka; Didcmnutn (Didcmnu)n) mosclcyi (Herdman); Symplegma viridc Herdman. Sla. 67. 7 August. Reef in pass west of Nghus ("Ankosu") southern tip of Urukthapel : 7°13'14" N., 134°22'10" E. (HO 0078, 1st ed.). Depth r>-7 ft. ; bot- tom living and dead coral, sand, coi'al rubble. Didcmnum (Didcmnum) tcrnatanum (Gottschaldt).