Alonella nana
Alonella nana is the smallest of the cladoceran species having a shape that is almost semicircular and a carapace that has an especially distinct and characteristic striping. It is a very common littoral chydorid which is found “everywhere”.
Key characteristics
Alonella nana (female)
Alonella nana is the smallest of the cladoceran species, having a shape that is almost semicircular. Its carapace has an especially distinct and characteristic striping. The colour is grey with elements of green and brown.
Female: Length 0.2–0.3 mm
Male: Length 0.2–0.3 mm
Ecology and distribution
A. nana is a very common littoral chydorid which occurs in 47 % of the investigated waters from all parts of the country. It is found close to the sea level though not in brackish water. Its frequency decreases with increasing altitude, though it is found as high as 1380 m a.s.l. A. nana is common in water bodies of all sizes, and lives in a great variety of habitats. The species is also found during the winter, with males mainly occurring in late autumn. pH in lakes containing A. nana varies between 3.9 and 8.6 while conductivity varies between 0.4 mS/m and 142 mS/m.
| Vitenskapelig navn | < 4,5 | 4,5 - 4,9 | 5,0 - 5,4 | 5,5 - 5,9 | 6,0 - 6,4 | 6,5 - 7,0 | 7,0 - 7,4 | > 7,5 |
|---|---|---|---|---|---|---|---|---|
| 53 | 64,7 | 57,9 | 62,5 | 51,2 | 41,1 | 47,1 | 39,7 |
| Vitenskapelig navn | < 1,0 | 1,0 - 1,4 | 1,5 - 1,9 | 2,0 - 2,9 | 3,0 - 3,9 | 4,0 - 4,9 | 5,0 - 6,9 | 7,0 - 9,9 | > 10,0 |
|---|---|---|---|---|---|---|---|---|---|
| 41,1 | 44,4 | 53,2 | 53,5 | 56 | 53,7 | 52,9 | 51,9 | 39,6 |
| Vitenskapelig navn | < 0,01 | 0,01 - 0,09 | 0,1 - 0,9 | 1,0 - 9,9 | 10,0 - 99 | 100 - 999 | > 1000 |
|---|---|---|---|---|---|---|---|
| 34,3 | 28,9 | 50,4 | 54,2 | 51,1 | 53,4 | 54,3 |
| Vitenskapelig navn | < 100 | 100-299 | 300-499 | 500-699 | 700-999 | >1000 |
|---|---|---|---|---|---|---|
| 54 | 57,1 | 52,7 | 48,6 | 41,6 | 29,6 |
Look-alikes
Chydorus sphaericus
