Eophrynus is an extinct genus of arachnids from the extinct order Trigonotarbida, which lived during the Late Carboniferous period in Europe.

[1] The name comes from Eo, meaning 'dawn', and Phrynus, an extant genus of whip spider (order Amblypygi).

Two species have been recognised: Species of Eophrynus, as with other tribonotarbids, were similar to modern spiders but could not produce silk and the back-half of their body was made up of small plates.

[2] The English species, E. prestvici, is known from a handful of good quality fossils preserved inside siderite concretions.

Recent X-ray imaging revealed that these arachnids were covered by protective spikes.