Revista Chilena de Historia Natural 76 (2): 297-312, 2003
RESEARCH ARTICLE
The distribution of littoral caprellids (Crustacea: Amphipoda:Caprellidea) along the Pacific
coast of continental Chile
Many littoral caprellid species have a very ample distribution, some having been reported
from all over the world. The cosmopolitan distribution of many littoral caprellid species might be facilitated by the fact that they are often
associated with fouling communities on floating objects, which have a high potential of far-range dispersal. This dispersal potential
may also have implications for the distribution of caprellids on local and regional scales. Herein we examined the distribution of littoral
caprellid species on two spatial scales, local (tens of kilometers) and regional (hundreds of kilometers) along the Pacific coast of
continental Chile. On the local scale, we studied the caprellid fauna in different habitats (intertidal boulders, subtidal algal and seagrass
beds, fouling community on buoys and ropes); on the regional scale we focused only on caprellids associated with the fouling
community on buoys and ropes. We found a total of six caprellid species, some of which were very abundant both on the local as well
as on the regional scale. On the local scale we found a difference between the three studied habitat types with respect to the
assemblage of caprellid species, some of which were found in more than one habitat. The highest species richness and abundance of
caprellids was found in the fouling community associated with anchored buoys and ropes. On the regional scale we found very high
numbers of caprellids in the fouling community of the northern region (n of 30°S), and decreasing abundances and species richness in
the central region (30–37°S). No caprellids were found in the southern region of the study area (37–42°S). This pattern coincides with
the global distribution of littoral caprellid species, which are most abundant and diverse at low latitudes but occur in low abundances
and low diversity at high latitudes. Detached buoys that were found a few km off the coast harbored similar caprellid assemblages
(including ovigerous females) as anchored buoys, suggesting that buoys and other floating substrata (litter, macroalgae) may facilitate
dispersal of caprellids (and other epibiota) along the Pacific coast of Chile. Since artificial and natural floating substrata are also
abundant at high latitudes it is inferred that the low diversity of littoral caprellids at high latitudes is not due to lack of dispersal vectors,
but rather of other factors.
Key words:
Crustacea, Amphipoda,
Caprellidea, Chile, biogeography
