Definition: Deriving energy from light sources. In practice, taxa containing plastids and photosynthetic pigments, but with no evidence for consumption of organic particles or prey, are considered to be photoautotrophic. (Barton, AD, Finkel, ZV, Ward, BA, Johns, DG, Follows, MJ. 2013. On the roles of cell size and trophic strategy in North Atlantic diatom and dinoflagellate communities. Limnol. Oceanogr., 58(1), 2013, 254–266. doi:10.4319/lo.2013.58.1.0254)
Definition: position of an organism in a food web. May be described verbally with descriptors including primary producer, herbivore or carnivore. If described numerically, 1 indicates a primary producer, 2 a herbivore, and so on up the food web.