Free Content Aplacophoran Molluscs: Deep-Sea Analogs to Polychaetes

 Download
(PDF 927.7kb)
 
Download Article:

Abstract:

Species of aplacophoran molluscs belonging to the burrowing family Prochaetodermatidae are often among the dominant species at particular localities in the deep-sea benthos, ranging up to 480 m−2 They outnumber most species of the three dominant groups: polychaetes, peracarid crustaceans, and other molluscs. Their success is attributed to their utilization of a broad food source and rapid growth and maturation within 1 year after settlement. In three areas for which quantitative data are available—the northwest Atlantic, the northeast Pacific, and the Aleutian Trench—the prochaetodennatid species at the midpoints of their vertical ranges were usually among the five top dominants and usually were outnumbered only by polychaetes. A Bray-Curtis similarity coefficient and group average sorting of the fifty most abundant species off the Farallon Islands clustered six polychaete species and a prochaetodermatid (Blake et al., 1992). These results were tested statistically over the seven deepest box cores by median numbers and variances of the means among the seven species, and by correlations of the number of individuals between paired species. The results showed that the single spionid species in the cluster apparently had little effect on the other six species. Correlation coefficients showed that every species except the spionid had a significant pairing effect with at least one other species in the group. Of the five nonspionid polychaete species, all are motile burrowers; three belong to the Paraonidae and one each to the Cossuridae and Cirratulidae. Except for the cirratulid, all appear to be foragers like the prochaetodennatid. It is suggested that the same food source is shared by the six species; that predator-prey interactions and competitive resource partitioning do not determine their relationship to each other; and that the group as a whole is probably a determinant of population structure. The presence of a mollusc amongst a nested group of polychaetes cautions against using higher taxa as functional units.

Document Type: Research Article

Publication date: March 1, 1997

More about this publication?
  • The Bulletin of Marine Science is dedicated to the dissemination of high quality research from the world's oceans. All aspects of marine science are treated by the Bulletin of Marine Science, including papers in marine biology, biological oceanography, fisheries, marine affairs, applied marine physics, marine geology and geophysics, marine and atmospheric chemistry, and meteorology and physical oceanography.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Terms & Conditions
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more