Platyhelminthes : While flatworms are present, probably in large numbers, 

 their identification is difficult. The author has observed at least three 

 species in working with the Mytilus communities. If proper identification 

 could have been made, possibly two specimens might have been representative 

 of different species, making four species present. 



Nemertea : Several ribbon worms have been observed around the island, but 

 none have been identified. 



Annelida : Annelid worms are probably the most common type of worm 

 found in the ocean and this is also true at Rincon. Most of the annelids 

 are larger and more easily classified, which explains the numbers that 

 have been identified for this study. As in the case of the worms listed 

 above, there are probably many more species present, but collecting and 

 classifying them is not easily done. The following is a list of the 

 annelids that have been cataloged: 



Table 4. 



Annelids at Rincon Island 



Common Name 



Scientific Name 



Parchment tube worm 



Chaetopterus vaviopedatus (Renier) 



Feather-duster worm 



Eudistylia polymorpha (Johnson) 



Nereid worm 



Eunereis longipes Hartman 



Scale worm 



Halosydna brevisetosa Kinberg 



Nereid worm 



Nereis edkini Hartman 



Nereid worm 



Nereis mediator Chamberlin 



Qirysopetalid worm 



Faleonotus bellis (Johnson) 



Colonial tube worm 



Salmaaina tribranchiata (Moore) 



Serpulid worm 



Serputa vermioularis Linnaeus 



Serpulid worm 



Spirorbis sp. 



Arthropoda : Many arthropods are important to skin and scuba divers as 

 game and to the fishery industry for commercial use. This is also 

 true of the area around Rincon Island since the construction of the island 

 has provided the necessary shelter and breeding area for the larger crus- 

 taceans. During the commercial season licensed fishermen place a large 

 number of lobster pots around the island and take an average of 10 lobsters 

 per day along with a number of cancer crabs. 



Arthropods in general and crustaceans in particular are very sensi- 

 tive to hydrocarbons. This sensitivity is important at Rincon Island as 

 it provides a natural indicator for any type of oil seepage. The abun- 

 dance and diversity of crustaceans would seem to indicate the success of 

 the safeguards employed to eliminate spills and contamination on and 

 around the island. 



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