Chara connivens Saltzm. Ex. A. Braun 1835 found in the Åland archipelago – a new species to Finland Kajsa Appelgren, Martin Snickars & Johanna Mattila Husö Biological Station and Dept. of Biology, Environmental and Marine Biology, Åbo Akademi University, Akademigatan 1, FI-20500 Åbo, Finland (e-mail: kajsa.appel- gren@abo.fi) Convergent stonewort, Chara connivens Saltzm. Ex. A. Braun 1835, was found in the northern Åland archipelago in July 2004 and confirmed finally in September 2004 when the individuals had turned fertile. Only female plants were found. This is the first con- firmed find of the species in Finland. C. connivens was found at a depth of 0.5–1.5 meter outside a shallow bay. The bottom substrate was silt mixed with small sized gravel and sand. The area was sheltered but had still a good water exchange. The water adjacent to the Chara meadows was very clear and weakly mesohaline. Herbarium examples are kept at the University of Helsinki (H) and Åbo Akademi University (TUR-A). Introduction Convergent stonewort, Chara connivens Saltzm. Ex. A. Braun 1835, was found in the northern Åland archipelago (60°23.158’N 19°57.261’E, Geta) in July 2004. The species formed a meadow outside a flad, i.e. a bay in isolation phase under land uplift. The first specimens were immature in- dividuals and thus the species identification could no be verified. New specimens from the same site were collected in September 7th 2004. This time they were mature, and the species identification could be completed (Torn & Martin 2003). Only female plants were found. Species identification was confirmed by Dr. Irmgard Blindow (Univer- sity of Greifswald, Germany). Herbarium exam- ples are kept at the University of Helsinki (H) and Åbo Akademi University (TUR-A). Identification C. connivens is usually about 15 cm long, rarely up to 40 cm (Fig. 1). The plants are fresh green, triplo- stichous and isostichous. Spine-cells are almost lacking. Branchlets are situated in whorls of 6–10 with 8–10 segments. The upper one-two may be short. Internodes are up to six times as long as branchlets. The species is dioecious. Branchlets of fertile female plants are curved inwards. The oogonium is 650–1100 × 320–550 μm and has 13– 15 helical stripes. The colour of oogonium is or- ange to brown. Oospores are dark brown to black with 11–14 weakly distinguishable ridges. Their size is 500–700 × 240–350 μm. C. connivens can be mixed with C. globularis. C. connivens is some- what more robust than C. globularis, but a distinc- tive identification is possible only when plants are fertile (Torn & Martin 2003). Distribution and habitat C. connivens occurs in Europe, Africa and north- ern Asia (Luther 1979, Krause 1997, Torn & Mar- tin 2003). The species is rare in the Baltic Sea (Olsen 1944, Trei 1991). Luther (1979) only men- tioned single records from Sweden and Germany. Recent records exist only from Sweden (Blindow 1988, Wallström & Persson 1999, Torn & Martin Memoranda Soc. Fauna Flora Fennica 80:11–13. 2004