Bornella valdae
Pola, Rudman & Gosliner, 2009

Family: Bornellidae


Known only from KwaZulu Natal, South Africa.


Upper: KwaZulu Natal, South Africa. Photo: Valda Fraser. Lower: Scanning electron micrograph of half radula. Scale bar = 20µm. SEM Photo: M. Pola.

The elongate body shape is typical of species of Bornella with large raised rhinophore sheaths anteriorly and a series of paired dorso-lateral mantle processes running down the body. The oral tentacles are lobe-like with a series of finger-like papillae.  

The notum is smooth but when the body is slightly retracted there are traces of transverse wrinkling. The background color of the body is opaque white, with a reticulated pattern of orange-red covering the sides of the body. The head and the anterior side of the rhinophore sheaths are orange-red with a pattern of white spots, and the rhinophores are translucent orange-red.. The dorso-lateral processes are white sometimes with a yellowish band and sometimes with traces of a red reticulate pattern. The most distinctive feature of the colour pattern is the opaque white band which runs from the rhinophores back along the dorsal surface of the animal between the dorso-lateral processes.

Each rhinophore sheath has a tall cylindrical stalk from which the rhinophore protrudes. Surrounding the upper edge of the sheath, are three long, anterior and anterolateral papillae and a taller, wide posterior sail which has three large, similar-sized, sharply pointed branches. Behind the rhinophores are five pairs of dorso-lateral processes, followed by a single one in the dorsal midline. The first and second processes on each side have two larger inner papillae and two smaller outer ones, while the processes in the third and fourth pair have only two papillae. Behind the fourth pair, the processes are simple. Gills are found on the inside of the four anterior-most pairs of processes. The living adults are large, growing to at least 70 mm in length.

This species is named after Valda Fraser who has beena contributor to the Forum for many years.

  • Pola, M., Rudman, W. B. & Gosliner, T. M. (2009) Systematics and preliminary phylogeny of Bornellidae (Mollusca: Nudibranchia: Dendronotina) based on morphological characters with description of four new species. Zootaxa, 1975, 1-57.
Authorship details
Rudman, W.B., 2009 (January 27) Bornella valdae Pola, Rudman & Gosliner, 2009. [In] Sea Slug Forum. Australian Museum, Sydney. Available from