Spintheridae is a family of marine polychaete worms with a single genus, Spinther, containing these species:
Spinther alaskensis Hartman, 1948
Spinther arcticus (M. Sars, 1851) (includes Spinther miniaceus Grube, 1860)
Spinther australiensis Augener, 1913
Spinther citrinus (Stimpson, 1854)
Spinther ericinus Yamamoto & Imajima, 1985
Spinther hystrix Uschakov, 1950
Spinther japonicus Imajima and Hartman, 1964
Spinther oniscoides Johnston, 1845
Spinther sagamiensis Imajima, 2003
Spinther usarpia Hartman, 1967
Spinther vegae Augener, 1928 (includes Spinther wireni Hartman, 1948)
The animal lives as a symbiont on sponges.
Johnston's paper does not explain the choice of the name, but ancient Greek σπινθήρ means "spark." In images of the living animal, it appears to be surrounded by a cloud of pinpoints of light.