Tetrachaelasma southwardi Newman & Ross, 1971. Specimen (MACN-In 44478l): A, B. Left and right mandibles, respectively, inferior angles enlarged; C, D. Right and left first maxillae, respectively; E. Second maxilla, only some setae drawn, all of them serrulate (see detail); F–I. Left cirri I-IV, respectively; the first antenniform article is indicated with an asterisk; J. penis, only a short section of annuli is drawn. Abbreviations: a – anterior ramus; p – posterior ramus. Scale bars: 1 mm (A–E); 0.5 mm (F–J).

 
 
  Part of: Chiesa IL, Pereira E, Roccatagliata D (2024) On the occurrence of the deep-sea barnacle Tetrachaelasma southwardi Newman & Ross, 1971 (Cirripedia, Balanomorpha, Bathylasmatidae) in the Mar del Plata Submarine Canyon, Argentina: supplementary description and taxonomic remarks on the genus. Zoosystematics and Evolution 100(2): 603-623. https://doi.org/10.3897/zse.100.118912