The influence of hypo‐osmotic stress on the regenerative capacity of the invasive polychaete Marenzelleria viridis from its native range |
| |
| Authors: | Andrew A David Jason D Williams |
| |
| Institution: | Department of Biology, Hofstra University, Hempstead, NY, USA |
| |
| Abstract: | The euryhaline polychaete Marenzelleria viridis is a notorious invader of the Baltic region and while many studies have focused on the effects of osmotic stress on larval development of the species, few have assessed its effect on adult specimens. This study investigated the effects of low salinity on the physiology of M. viridis by using its regenerative capacity as a proxy for physiologic performance. Specimens were collected in spring 2015 on sandy flats in Hempstead Bay (Long Island, New York), a site that falls within its native range. Worms were ablated between the 14th and 20th chaetigers and cultured at five different salinity treatments (24psu, 15psu, 10psu, 5psu and 0psu) that reflected the broad salinity regimes of its distributional range. Data for anterior regeneration were analysed and presented. Morphogenesis during anterior regeneration was characterized by the formation of a blastema from which the major anatomic structures emerged. All specimens cultured at 5–24psu successfully completed regeneration whereas 75% of specimens cultured at 0psu died and the survivors were unable to proceed beyond the blastema stage. Salinity did not have an effect on regeneration time (14.5–15.1 days) but did have an effect on the percentage of chaetigers regenerated (lowest – 77% at 5psu, highest – 97.5% at 15‰). The post‐regeneration phase was characterized by variability in pigmentation patterns in the regenerated anterior structures, which appear to be independent of salinity treatments. In conclusion, adult M. viridis appears to exhibit high tolerance to low salinity environments, which may have been inherited from its larval stages. In addition, the different pigmentation patterns observed in regenerated structures may allude to the variability of this feature in spionids. |
| |
| Keywords: | Euryhaline Hempstead physiology salinity spionid tolerance |
|
|
