1属1種。幅広い鋤骨歯叢を備える点で本属に類似するJaponocongerミナミアナゴ属では,前上顎骨歯叢と鋤骨歯叢が連続せず,Acromycterヒモアナゴ属では後鼻孔が眼の前縁上方に,Promyllantorでは前縁下方に位置する(Blache and Bauchot, 1976)。 (上野・佐々木)
Distinctive characters:
Mouth inferior. Anus situated forward of mid-body, total length 2.6〜2.7 times of preanal length. Dorsal origin behind tip of pectoral, distance from gill-opening to dorsal origin is about equal to half of head length. Dorsal and anal fin rays segmented. Pectoral rather small, its length equal to eye. Labial flange absent on upper jaw. Maxillary pores large and distinct. Posterior nostril in front of eye. Teeth on maxillary and dentary 3〜5 rows in bands, some molar teeth present on innermost rows; premaxillary tooth patch and vomerine tooth patch connected each other directly. Gill-opening and anus black.
Distribution:
Widely distributed in the Atlantic Ocean.
Remarks:
Monotypic genus. Among the genera characterized by wide vomerine tooth patches, the patches of premaxillary and vomer not confluent in Japonoconger, the posterior nostril of Acromycter situated above the anterior margin of eye, and of Promyllantor below the margin (Blache and Bauchot, 1976). (Uyeno and Sasaki)