Cirripedia of Enewetak Atoll 



Chapter 1 8 



RICHARD H. TITGEN 



Bernice P. Bishop Museum 

 Honolulu. Hawaii 9681 7 



INTRODUCTION 



Barnacle research at Enewetak Atoll, Marshall Islands, 

 has been incidental to other marine studies. There have 

 been just two published reports. Zullo et al. (1972) 

 reported specimens of Balanus amphitrite arnphithte 

 Darwin, 1854, and Balanus eburneus Gould, 1841, in the 

 collections of the California Academy of Sciences. Tomlin- 

 son (1973) reported the acrothoracican barnacles 

 Lithogliiptes bicornis Aurivillius, 1892 (as Lithogl^ptes spi- 

 natus Tomlinson and Newman, 1960), Lithoglvptes mitis 

 Tomlinson, 1969, and Criiptophialus heterodontus Tomlin- 

 son, 1969, from shells in the U. S. National Museum of 

 Natural History's Division of Malacology. Both of the 

 Balanus spp. are cosmopolitan in warm and temperate 

 seas; they are commonly transported as fouling organisms 

 and were introduced to Enewetak (W. A. Newman, per- 

 sonal communication). The acrothoracican barnacles 

 reported by Tomlinson (1973) also have relatively wide 

 distributional ranges, but these were established by natural 

 means. However, because acrothoracicans lack plankto- 



trophic larvae, their long-range dispersal mechanisms are 

 not understood. 



Nine sp>ecies of barnacles are known from Enewetak 

 Atoll, four of which are new records supplied by W. A. 

 Newman. In comparing barnacle records from Enewetak 

 Atoll and the other Marshall Islands (Henry, 1957; Tomlin- 

 son, 1969, 1973; Zullo et al., 1972; Newman and Tomlin- 

 son, 1974; and Grygier, 1981a) to sf>ecies reported from 

 the Caroline Islands (Hiro, 1937, 1938; Boschma, 1953, 

 1955; Henry, 1957; Newman, 1960a, 1972; Tomlinson, 

 1969, 1973; Ross and Newman, 1973; and Newman and 

 Ross, 1976), there is a strong indication that more barna- 

 cles should occur at Enewetak Atoll than have been 

 reported. The proximity of the Caroline Islands to the 

 Marshall Islands suggests that many of the Caroline Island 

 species, or closely related ones, may occur in the Marshall 

 Islands and at Enewetak Atoll. However, it will take a 

 directed effort to collect and identify the barnacle species, 

 rather than the incidental collecting that has occurred pre- 

 viously, because tropical barnacles tend to be cryptic and 

 sparsely distributed as compared to temperate forms (New- 

 man, 1960b). 



Because so few of the species that may occur at 

 Enewetak Atoll have been reported, the included checklist 

 (Table 1) also lists species that probably occur at 

 Enewetak Atoll. 



TABLE 1 



Checklist of Shallow-Water Cirripedia Found, or Likely to Be Found, 

 in the Waters Surrounding Enewetak Atoll* 



Subphyium CRUSTACEA 

 Class MAXILLOPODA 

 Subclass CIRRIPEDIA 



Order ASCOTHORACICA 

 Suborder SYNAGOGOIDIDA 

 Family SYNAGOGIDAE 



f Corgonolaureus bikiniensis Utinomi, 1962. 

 Order THORACICA 



Suborder LEPADOMORPHA 



Family HETERALEPADIDAE 



-fHeteralepas hataii Hiro, 1937. 



fHefera/epas spp. 



■fParalepas palinuri (Barnard, 1924). 



'Systematic hierarchy taken from Bowman and Abele (1982). 

 fSpecies likely to be found at Enewetak Atoll. 



(This table continued on next page.) 



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