Chromodoris dianae can reach a maximum size of 4 cm length.Christian Robilliart (19 August 2011) Chromodoris dianae. At Sous les Mers. The body is elongate with a foot which is distinct from the upper body by a skirt like mantle partially hiding the foot. This species is very similar in appearance to Chromodoris lochi although it can be distinguished from the latter by the broken black lines, (as opposed to continuous) and the sprinkling of white specks on the notum.P.L. Beesley, G.J.B. Ross, A. Wells, (1998) Mollusca - The southern synthesis, vol.5, CSIRO, 1998, Behrens, D. W., 2005. Nudibranch behaviour, New World Publications Inc., Gary Cobb & Richard Willan, Undersea jewels - a colour guide to nudibranchs, Australian Biological Resources Study, 2006, Chromodoris dianae has white gills and rhinophores with distinct yellow-orange tips. The original description includes animals which belong to another species (Chromodoris cf. dianae) which are distinguished by a colour pattern which includes gills and rhinophores orange throughout, orange markings at the edge of the mantle and a different pattern of black markings; confirmed as species level differences by DNA sequences.Rudman, W.B., 2001 (Jun 25). Comment on Variation? in Chromodoris dianae by Bernard Picton. [Message in] Sea Slug Forum. Australian Museum, Sydney.Gosliner, T.M., Behrens, D.W. & Valdés, Á., 2018. Nudibranch and Sea Slug Identification - Indo-Pacific. New World Publications; 2nd Revised, Updated edition. 452 pp. , , p. 137
