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Evadne nordmanni

Lovén (1836)

Download a fact sheet for Evadne nordmanni (PDF 288KB)

Taxonomy

Phylum Arthropoda
Subphylum Crustacea
Class Branchiopoda
Subclass Phyllopoda
Order Diplostraca
Suborder Cladocera
Family Podonidae
Genus Evadne
Species nordmanni

Size

  • Female: 0.4 - 1.4 mm
  • Male: 0.4 - 0.8 mm

Distinguishing characteristics

  • Carapace always pointed at posterior end
  • 2 antennal elevator muscles lying parallel to each other

Male

  • Carapace triangular in lateral view, separated from head with adorsal depression
  • Compared to female, head and eyes are larger and lower edge is curved more sharply
  • Distal segment of endopodite of leg 1 has strong, inwardly curved hook
  • Copulatory organ is cylindrical, distally with longitudinal grooves

Female

  • In lateral view oval or triangular (depends on devision stage of embryos)
  • Brood pouch narrowing posteriorly, pointed or more or less rounded with short spine
  • Head small compared to body, anteriorly rounded regularly, faintly convex near antennulae@
  • Compound eye large, but by far not occupying the forehead
  • Antennulae very small, fused at base; pointed in lateral view, rounded distally, bearing 3-4
  • Legs rather short, first leg not elongated
  • Postabdomen very short and bifurcated
  • Up to 7-8 embryos in the brood pouch

Distribution

Ecology

References

  • Flößner, D., (1972) Kiemen- und Blattfüßer, Branchiopoda; Fischläuse, Branchiura. Die Tierwelt Deutschlands, 60. Teil. Gustav Fischer Verlag, Jena.