Halgerda
Halgerda is a genus of sea slugs, dorid nudibranchs, shell-less marine gastropod mollusks in the family Discodorididae.
Taxonomy
The genus Halgerda was classified within the family Halgerdidae by Odhner.Halgerdidae Odhner, 1926, is treated as a synonym of Discodorididae in the taxonomy of Bouchet & Rocroi. See also Valdés.
Seven species of Halgerda were described in the years 1880-1905, two species in 1932-1949, four species from 1975-1982, then 22 species in the years 1993-2001. In 2018 another six new species were described from Mozambique, highlighting the number of undescribed species on the African coast of the Indian Ocean. A number of undescribed species are known and many species show considerable variation across their ranges, which may indicate that more cryptic species exist.