Purple-lined Nembrotha

Nembrotha purpureolineata is a large pale-bodied dorid that may reach a total length of 120 mm. Individual specimens vary extremely in terms of colour and patterning, which can make it very difficult to differentiate from other Nembrothids. Thankfully, progress continues to be made in fine-scale differentiation within the genus, bringing great clarity to colour morphotypes that have been regarded as cryptic in the past. The base colour of the body is always a creamy white, a blue to purple line always edges the foot and oral tentacles and there are always brown markings. The brown markings may present as longitudinal lines of variable thickness. A thinner line begins anterior to and passing beneath the rhinophores, running along the edge of the notum and meeting posterior to the gills to form a single broad line that runs down the tail. Thicker line or lines occur between these, and will form broad patches on the notum anterior and posterior to the gills. Some of these lines will terminate at the gill circle instead of parting around it. One or more lines occur on the sides of the body to meet at the tail as well. The lamellate rhinophores are described as "red or vermillion with blue or purple tips". The rhinophore stalks are pink, and the sheaths blue to purple with some yellow below, either concentrated or diffuse. …

This species feeds on ascidians and tunicates. It has been seen feeding on the yellow-lined ascidian, Clavelina meridionalis.