The snake eels of the ophichthid genus Brachysomophis (subfamily Ophichthinae) are revised to include: B. atlanticus Blache and Saldanha, from Sénégal and off Principe Island; B. cirrocheilos (Bleeker), widespread in the Indo-Pacific; B. crocodilinus (Bennett) (with its synonyms Achirophichthys typus Bleeker, Brachysomophis horridus Kaup, and Brachysomophis sauropsis Schultz), widespread in the Indo-Pacific; B. henshawi Jordan and Snyder, widespread in the Indo-Pacific; B. porphyreus (Temminck and Schlegel) (with its synonym Ophichthys adspersus Günther) from China and Japan; and 2 new species, B. longipinnis n. sp. from the Taiwan Strait, trawled in 50 m, and B. umbonis n. sp. from Mindoro, Philippines, and Flores, Indonesia, poisoned in 14-18 m. Achirophichthys Bleeker is a junior synonym of Brachysomophis Kaup. Brachysomophis (Achirophichthys) kampeni Weber and de Beaufort is referred to Lamnostoma. Mystriophis Kaup is restricted to include the Atlantic species M. rostellatus (Richardson) and M. crosnieri Blache. All other species previously referred to Mystriophis (Mystriophis blastorhinos Kanazawa, Leptocephalus caudomaculatus Eigenmann and Kennedy, Mystriophis creutzbergi Cadenat, Ophisurus intertinctus Richardson, Conger mordax Poey, Crotalopsis puncrifer Kaup, and Ophichthys schneideri Steindachner) are referred to other genera. A key to the species of Brachysomophis, illustrations of all species, and maps of their distribution are provided. A neotype is selected for B. crocodilinus, and a lectotype is designated for B. horridus.