Polydora and Related Genera (Annelida, Polychaeta) from 
Eniwetok, Majuro, and Bikini Atolls, Marshall Islands 
Keith H. Woodwick 1 
ABSTRACT: In a study of more than 250 specimens of spionid polychaetes col- 
lected at Eniwetok, Majuro, and Bikini atolls, Marshall Islands (1956 and 1957) 
five new and two known species were found. 
One of the species (T. spinosa) is the type for a new genus, Tripoly dora, which 
is closely related to Polydora, Pseudopoly dor a, and Boccardia by virtue of its modified 
fifth segment. It is unusual in having branchiae on the fifth segment, and the 
hooded hooks are trifid and begin on Segment 9. The other new species are 
Pseudopolydora corallicola, Pseudopolydora pigmentata, and Polydora tridenticulata 
from coral material, and Pseudopolydora reishi from areas of pollution. The known 
forms, Pseudopolydora antennata Claparede and Polydora armata Langerhans, are 
considered in reference to the literature. 
The ecologic and systematic positions of the seven species are discussed. 
In A study of a group of spionid polychaetes 
collected at Eniwetok, Majuro, and Bikini atolls, 
Marshall Islands, in 1956 and 1957, five poly- 
dorids new to science were found and are 
described herein. In addition, information is 
provided concerning the natural history and 
distribution of two known species present. The 
material was collected by Dr. Donald J. Reish, 
Department of Biological Sciences, Long Beach 
State College, Long Beach, California. The field 
work was made possible by the U. S. Atomic 
Energy Commission through its Eniwetok Ma- 
rine Biological Laboratory. 
More than 250 specimens were collected, in- 
cluding five new species and Polydora armata 
Langerhans and Pseudopolydora antennata ( Cla- 
parede). The new species belong to Polydora 
Bose, Pseudopolydora Czerniavsky, and a closely 
related new genus, Tripolydora. The new forms 
include Polydora tridenticulata, Pseudopolydora 
corallicola, Pseudopolydora pigmentata, Pseudo- 
polydora reishi, and Tripolydora spinosa. 
1 Department of Biology, Fresno State College, 
Fresno, California. Manuscript received July 30, 1962. 
Among papers providing information con- 
cerning polydorid forms from the Marshall Is- 
lands area or related ecological regions are those 
of Hartman (1954) and Okuda (1937). Hart- 
man reported Polydora spp. from various parts 
of Eniwetok Atoll. She noted that one of these 
resembled P. armata . Okuda reported P. armata 
and Ps. antennata from coral and related habitats 
of southern Honshu, Japan. 
Collections from the three atolls include ma- 
terial from such diverse habitats as sandy mud 
to algal materials (including coralline algae), 
but mainly from coral rocks. Both the ocean 
and lagoon sides of the atolls were sampled, as 
were the near, middle, and far sides of the 
various islands (Fig. 1 and Table 1). The col- 
lection periods were from August 22, 1956, to 
September 7, 1956, and from June 30, 1957, to 
July 15, 1957 (collections during 1957 at Eni- 
wetok Atoll only ) . Ecological factors of the col- 
lecting areas will be presented in the discussion 
of the respective species. 
The holotypes are in the U. S. National Mu- 
seum and the remainder of the specimens are 
at the Eniwetok Marine Biological Laboratory. 
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