Question: Starfish stars an actor of what nationality?

Context articles: Asterias
Asthenosoma marisrubri
Asterozoa
Brittle star
Ossicle (echinoderm)
Sea star wasting disease
Astropectinidae
Starfish (film)
Starfish
Tom Riley (actor)

Asterias is a genus of the Asteriidae family of sea stars.
 It includes several of the best-known species of sea stars, including the (Atlantic) common starfish, "Asterias rubens", and the northern Pacific seastar, "Asterias amurensis".
 The genus contains a total of six species in all.
Asthenosoma marisrubri ('flexible body of the Red Sea') (Weinberg & De Ridder, 1998) aka Red Sea fire urchin and toxic leather sea urchin , is a relatively common sea urchin with a widespread distribution in the Indo-Pacific, and was till 1998 considered a color variant of "Asthenosoma varium".
 Sea urchins are close relatives of starfish, crinoids, brittle stars and sea cucumbers, all being echinoderms ('spiny skins').
The Asterozoa are a subphylum in the phylum Echinodermata.
 Characteristics include a star-shaped body and radially divergent axes of symmetry.
 The subphylum includes the two classes Asteroidea, the starfish, and Ophiuroidea, the brittle stars and basket stars, and the extinct order Somasteroidea.
Brittle stars or ophiuroids are echinoderms in the class Ophiuroidea closely related to starfish.
 They crawl across the sea floor using their flexible arms for locomotion.
 The ophiuroids generally have five long, slender, whip-like arms which may reach up to 60 cm in length on the largest specimens.
 They are also known as serpent stars; the New Latin class name Ophiuroidea is derived from the Ancient Greek ὄφις, meaning "serpent".
Ossicles are small calcareous elements embedded in the dermis of the body wall of echinoderms.
 They form part of the endoskeleton and provide rigidity and protection.
 They are found in different forms and arrangements in sea urchins, starfish, brittle stars, sea cucumbers, and crinoids.
 The ossicles and spines (which are specialised sharp ossicles) are the only parts of the animal likely to be fossilized after an echinoderm dies.
Sea star wasting disease or starfish wasting syndrome is a disease of starfish and several other echinoderms that appears sporadically, causing mass mortality of affected starfish.
 There are around 40 different species of sea stars that have been affected by this disease.
 The disease seems to be associated with raised water temperatures.
 It starts with the emergence of lesions, followed by body fragmentation and death.
 In 2014 it was shown that the disease is associated with a densovirus now known as the sea star-associated densovirus (SSaDV).
The Astropectinidae are a family of sea stars in the order Paxillosida.
 In general, these starfish live on the seabed and immerse themselves in soft sediment such as sand and mud.
Starfish is a 2016 British drama film written and directed by Bill Clark, and starring Tom Riley and Joanne Froggatt.
 The film, based on a true story, follows a family who are thrown into turmoil when the husband contracts sepsis, a brutally damaging illness.
Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea.
 Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or "basket stars".
 About 1,500 species of starfish occur on the seabed in all the world's oceans, from the tropics to frigid polar waters.
 They are found from the intertidal zone down to abyssal depths, 6000 m below the surface.
Tom Riley (born 5 April 1981) is an English actor and producer.