ISSN:
1573-5125
Keywords:
Marenzelleria cf. wireni
;
Polychaetes
;
Marenzelleria cf. viridis
;
systematics
;
distribution
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Discrepancies are known to exist between the reproduction biology and population genetic of various Marenzelleria spp. populations in North American regions and in the North Sea and Baltic Sea. Species identification is difficult, and their geographical distributions are far from clear. As the diagnostic features of the species are known to vary with growth, it was necessary to find some reference frame within which morphological differences could be understood. The total number of setigers of intact specimens and the total number of branchiate setigers of anterior fragments proved to be suitable parameters permitting morphological differentiation between previously genetically distinguished forms. The forms corresponded in several features to literature diagnoses of M. wireni and M. viridis. Additional features were found to facilitate reliable morphological differentiation between the two species. It was shown that the range of distribution of M. cf. wireni is restricted primarily to mesohaline to polyhaline regions (including the North Sea), whereas M. cf. viridis is found predominantly in oligohaline to mesohaline areas (including the Baltic Sea). This applies also to North American and, possibly, polar waters. The discovery of M. cf. viridis in an oligohaline reach of the Elbe estuary shows that the two species can exist parapatrically, at least in North Sea estuaries. Besides these two species, a third was found to occur sympatrically with M. cf. viridis in a North American estuary (Currituck Sound). No description of this species has been given as the specimen consisted only of an anterior fragment.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009995119364
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