Helenodora is an extinct basal onychophoran or lobopodian genus known from the Carboniferous Carbondale Formation of Illinois. The only known species described is H. inopinata. The ecology of this animal is not well known, but it is thought that it may have lived on land and/or underwater. Helenodora was suggested by some authors to be a junior synonym of Ilyodes Scudder 1890, a fossil genus that includes two species and was originally described as a myriapod. A re-examination of the type material of Helenodora inopinata and the Ilyodes species found significant differences between them. Additionally, neither species of Ilyodes were adequately diagnosed, so they and the genus are all considered nomina dubia.