Lamprothamnium papulosum (Wallr. J. Groves 1916) (Charophyta)

Compiled by: Georg Martin, Estonia

1. Description of the habitat/autecology of the species

L. papulosum inhabits small sheltered bays with relatively hard bottom (sand, silty-sand, slity-shells or gravel with pebbles). Only few records are from areas wth soft substrates like clay or gyttija. L. papulosum is restricted to shallow water of 0.1-2.0 (to 3.2) m depth. In Denmark it was reported from salinity range of 8-18 psu (Olsen 1944), while in Sweden salinity ranges from 9.5-25 psu were observed.

2. Distribution (past and present)

L. papulosum has been recorded to inhabit coastal areas of Denmark, Germany and southern and southwestern Sweden. After 1981 the species disappeared from Swedish waters and occurrence in German waters of the Baltic Sea has declined.

3. Importance (sub-regional, Baltic-wide, global)

Species is considered to be very rare in the Baltic sea area. L. papulosum is very sensitive to eutrophication and mechanical disturbance.

4. Status of threat/decline

The decline of L. papulosum can be observed in its whole distribution area in the Baltic Sea, probably caused mainly by increased eutrophication, which results in higher turbidity and mass development of planktonic and filamentous algae during summer. In addition, increased tourism leads to intensified mechanical disturbance of shallow areas, e.g. by windsurfers and boating.

5. Threat/decline factors

Main known factors of threat are eutrophication and mechanical disturbance. 

6. Options for improvement

Prevention of eutrophication and concentrating on the conservation of the most important habitats of the species in various conservation networks will ensure the maintaining of the habitat for this species.

7. References

Andersson J., Garniel A., Nielsen R. 2003:  Lamprotahmnium papulosum. In Schubert, H., Blindow, I. (eds.), Charophytes of the Baltic Sea, Koeltz Scientific, Koeninstein/Taunus, 156-162.

Olsen S. 1944: Danish charophyta. Chorological, ecological and biological investigations. Kongel. Danske Vid. Selsk., Biol. Skr. 3: 1-240.