Identification Key to the Phyllidiids of the Indo-Pacific Ocean
According to morphological and anatomical features
Thanks to Alexander Fahrner and Lothar A. Beck

23. Ridges relatively smooth, evenly high, do not converge. Foot sole pale grey with numerous tiny, dark grey spots. Rhinophores black with pink stalk and 12-15 lamellae. - Phyllidiella rosans (Bergh, 1873)

- Ridges not smooth, evenly high, often converge anteriorly and posteriorly (Juveniles possess only 2-4 very low ridges). Foot sole uniformly white. Rhinophores entirely black, number of lamellae 20-23. - Phyllidiella zeylanica (Kelaart, 1859)