Eunice filamentosa

About Eunice filamentosa

Eunice filamentosa is retained here as the name reported in the Kauaʻi source, with an important qualification from later taxonomy. It is a marine jaw worm in Eunicidae, with three antennae, two palps and a separate pair of peristomial cirri. These sensory appendages are smooth in the modern redescription. The trunk has many bristle-bearing segments; the anterior region is more rounded and the posterior body becomes flattened. Fine chaetae, supporting aciculae and compound bristles are important identification structures that require microscopy.

The 2011 redescription examined the lectotype and additional specimens from the Gulf of Mexico and Caribbean. In its complete reference specimen, the gills began at the nineteenth bristle-bearing segment as single filaments, then became comb-shaped farther along the body, reaching four filaments in the posterior region. The terminal pygidium had two long dorsal and two very short ventral cirri. The study also recorded variation with size in the onset of gills and subacicular hooks. These details describe the revised reference species, rather than confirming that the Kauaʻi animal shared them.

That distinction matters because the revision changed the geographic interpretation of this name. Morphological comparisons and DNA barcodes separated Caribbean Eunice filamentosa from similar worms on the tropical eastern Pacific coast, which were assigned to a newly described species. The authors restricted Eunice filamentosa to the Grand Caribbean Region. A 2020 review likewise questioned widespread records and suggested that it did not occur in Australian waters. Neither publication examined the retained Kauaʻi record, so the Atlas preserves the historical identification while making the conflict visible.

Kauaʻi evidence comes from Appendix A, printed page 84, of Bishop Museum Technical Report 29a, with 1996 retained in the source evidence. It establishes that the name was reported in the island compilation; it does not demonstrate a verified modern occurrence of the revised Caribbean species, present abundance or native status.

The primary plate is a representative reconstruction grounded in the cited morphology reference. The historical name and its stated taxonomic uncertainty remain unchanged; the reconstruction does not supply missing specimen characters or resolve the identification beyond the evidence.