STUDIES ON THE FAUNA OF CURAÇAO AND OTHER CARIBBEAN ISLANDS: No. 163 The Cirripedia of Trinidad by Peter R. Bacon (Dept. of Biological Sciences, University of the West Indies, Trinidad) Page Figure Introduction 3 4 1 Description of the area Material and Methods 5 2 LEPADIDAE 1. Lepas anatifera.! 6 2. Lepas hillii 7 3. Lepas anserifera 7 4. Oxynaspis hirtae 9 3-4 BALANIDAE 1. Balanus tintinnabulum antillensis 12 2. Balanus eburneus 13 3. Balanus improvisus assimilis 14 5 4. Balanus amphitrite amphitrite 18 5. Balanus pallidus 18 6 6. Balanus venustus venustus 20 7 7. Balanus reticulatus 22 8. Balanus subalbidus 23 9. Balanus trigonus 23 10. Balanus calidus 23 8 11. Balanus galeatus 24 9 12. Tetraclita stalactifera 27 13. Tetraclitella divisa 28 14. Newmanella radiata 28 15. Ceratoconcha quarta 29 10—11 16. Chelonibia testudinaria. 34 17. Chelonibia caretta 34 18. Platylepas hexostylos 34 2 CHTHAMALIDAE 1. Chthamalus bisinuatus 35 12d-g 2. Chthamalus angustitergum 36 12a-c 3. Chthamalus rhizophorae 38 13—16 SACCULINIDAE 1. Ptychascus glaber 48 Discussion 48 References 52 INTRODUCTION The cirripede fauna of the island of Trinidad has been little investigated. SOUTHWARD (1962) recorded five species collected in north-west Trinidad for experimental studies; he listed Chthamalus Darwin var. fragilis on mangroves, Balanusamphitrite on mangroves and harbour piles, B. tintinnabulumLinnaeus on piles and Tetraclita radiata Blainville and T. rocks. The deter- squamosa Bruguiere on minations for all these species have been revised recently (SOUTH- WARD, 1975). Specimens of Newmanella radiata Blainville from the collections described below were included by Ross (1969) in his revision of the Tetraclita. A list of the Trinidad genus provisional cirripedes was in local given an appendix to a report on a swamp (BACON, 1970a) and reports have also been published on the fouling of mangrove oysters by barnacles (BACON, 1970b), barnacles commensal on leatherback turtles nesting in Trinidad (BACON, 1970c), the seasonal of larvae in estuarine occurrence cirripede local plankton (BACON, 1971a) and the ecology of B. eburneus Gould in a west coast man- Barnacles from the grove area (BACON, 1971b). mangrove areas as- signed provisionally in these reports to “B. amphitrite” and “C. fragilis”required further taxonomic study. The north coast of Trinidad was reported as one locality for the recently described species B. subalbidus (HENRY, 1973), and SOUTH- WARD'S report on the Intertidal and Shallow Water Cirripedes of the Caribbean includes further material from Trinidad. 4 The report which follows is mostly concerned with species not recorded by other authors, together with further data on the dis- tribution and general ecology of the Trinidad cirripedes. I to am indebted Drs. E. L. BOUSFIELD, National Museum of Canada; A. Ross, San Diego Natural History Museum; V. A. ZULLO, California Academy of Sciences, and H. G. STUBBINGS, British Admiralty Materials Laboratory, for assistance with determinations during the early stages of this study. Special thanks are due to Dr. A.J. SOUTHWARD, Marine Biological Association Laboratory, Plymouth, for making available his on the Caribbean and for manuscript cirripedes many helpful sugges- tions during the preparation of this report. I to the who assisted with the am grateful many persons collection of specimens, especially Professor J. S. KENNY, Messrs. D. RAMSAROOPand S. ALLICK, Department of Biological Sciences, University of the West Indies, Trinidad, and to Mr. P. PERCHARBE, Trinmar Ltd. Professor KENNY kindly provided salinity data for Saly- bia Reef and the directors of the Trinidad and Tobago Electricity Commission made available barnacles fouling the water cooling system of their Port of Spain plant. fromPanama Dr. C. BIRKLAND Specimens of C. rhizophorae were providedby and Dr. P. BOXSHALL kindly allowed me access to the cirripede collections of the British Museum. Thanks also to Mrs. West and to Miss are due S. RATTAN, University ofthe Indies, G. THOMPSON, University of Reading, for assistance with the laboratory work. DESCRIPTION OF THE AREA The Caribbean coast of Trinidad is dominated by steep cliffs and headlands formed the limestones and schists of the northern mountains. coral reefs by range Fringing in the east of the are developed, particularly near Galera Point, and some sheltered have small of river mouths. This is bays patches mangrove at the topography con- tinued throughoutthe north western peninsula and the islands of Monos, Huevos and Chacachacare. South east of Port of the coast is formed the Spain by mangrove swamps and, mudflats of the Caroni delta, interrupted north of Pointe-a-Pierre by firmer Tertiary sediments with occasional cliffs. South of San Fernando is a further low lying area of the South Oropuche Swamp, after which tertiary sand cliffs and rocky reefs dominate the coast to Icacos Point. Cliffs behind sand and pebble beaches continue along the south coast to Galeota Point. rocks These soft Tertiary are erodingrapidly, whereas the south west peninsula is actively accreting. east coast line of sand beaches to the the The presents a long exposed rough surf of central hills Atlantic Ocean. This is interrupted by promontories where the range reach the and into coastline north of Matura. cliffs and sea passes rocky Steep rocky reefs formed extension of the northern dominate the by the eastern range coast to Galera Point. ANDEL & POSTMA (1954) and GADE (1961) have described the water movements and marine conditions around Trinidad. The surface water is of variable origin, 5 predominatelysouth Atlantic except for the dry season, duringthe first four to five months of the when north Atlantic dominate. The south Atlantic year, waters water enters the area from the east as the Guianas Current and divides into one stream passing east and north of Trinidad and another which enters the Gulf of Paria. In the Gulf the currents north but the are generally going a clockwise eddy exists. During dry seasonwhen these currents are minimal,some Caribbean water enters at the sur- face from the north into the Gulf of Paria, while it is present at depth in the Bocas, between the western islands, throughout the year. The the Guianas Current and surface waters of are influenced by precipitation run off from the Orinoco and other South American rivers. This mixes vertically with the higher salinity water beneath and horizontally with the north equatorial current. Annual surface salinities from in the wet season to in the range 2-20%o 35%0 dry season in the eastern Gulf of Paria and from to on the east and north 33%0 36%0 coasts of Trinidad. The coast of Trinidad has a varied rock type and topography which produces a wide of habitats for barnacle colonisation. the low range However, predominately salinity conditions of the coastal environment, particularly in the Gulf of Paria, might be expected to restrict the numbers and distribution of the cirripedes. MATERIALS AND METHODS The material described was mostly collected at intervals from 1965 to 1974. A few older specimens from the collections of the Uni- West Indies versity of the are included also. The collection localities are shown in Figure 1 and, unless otherwise stated, all collections contained at least 10 animals. The descriptions follow widely accepted terminology. Where reference is made to types of setae on the appendages these are as shown in Figure 2. HENRY (1973) used similar terms to describe the setae but did not distinguish pectinate setae with basal guards. In this the base type two large spines are present at and separated by a from Pectinate short space the pectinated part of the seta (Fig. 2e). basal found in setae with guards were only some Chthamalids. The barnacle collections described here contain 26 taxa, 4 Lepa- domorpha, 21 Balanomorpha and 1 sacculinid. References under have been reduced omis- species synonymy by in DARWIN sion of earlier ones listed the monographs of (1854) and PILSBRY (1916) or listed in more recent major reviews, such as those 6 Fig. 1. Map of the island of TRINIDAD, showing collection localities. dealing with Balanus amphitrite (Harding, 1962) and B. trigonus (Werner, 1967). in this in the The specimens figured report are deposited British Museum (Natural at to History), London BM (NH) Registration numbers 1975: 981 1054. The re- maining material from which localities and other general data were obtained are deposited in the Department of Biological Sciences, University of the West Indies, Trinidad. Family LEPADIDAE Darwin Genus Lepas Linnaeus 1. Lepas anatifera Linnaeus Lepas anatifera, DARWIN, 1854, p. 73, pi. 1 fig. 1; PILSBRY, 1907,p. 79; 1927,p. 37; NILSSON-CANTELL, 1939, p. 3; WELLS, 1966, p. 88; SOUTHWARD, 1975, p. 3; ZEVINA, 1975, p. 234. 7 Fig. 2. Types of cirral setae: a — simple; b — pinnate; c — hooked; d — pectinate; e — pectinate with basal guards. On beach drift, Manzanilla, 1965; on driftwood and plastic flotsam, Matura, Feb. March 1973; on fishing float, Matura, 1974. This species is abundant on beach drift on the east coast and is commonly asso- ciated with the polychaete Amphinomerostrata (Pallas) and amphipods. 2. Lepas hillii Leach 1 80. Lepas hillii, DARWIN, 1854, p. 77, pi. fig. 2; PILSBRY, 1907, p. On beach drift, Rampanalgas, Apr. 1974. 3. Lepas anserifera Linnaeus NILSSON- Lepas anserifera, DARWIN, 1854, p. 81, pi. 1 fig. 4; PILSBRY, 1907, p. 80; ZEVINA, CANTELL, 1933,p. 504; 1939, p. 3; SOUTHWARD, 1975, p. 3; 1975, p. 234. On driftwood, Matura, May, 1967. this from collections of Seven specimens of uncommonspecies Trinidad are in the the National Museum of Canada (NMC. No. 67-373). 8 Fig. 3. Oxynaspis hirtae, from Chacachacare Bay. a — external features; b — external view of scutum; c — internal view of scutum; d — external view of tergum; e — f — labrum and — labral h k — left and mandibles of carina; palps; g palp; to right two specimens; l — first maxilla; m — second maxilla.