Unexpected species diversity in electric eels with a description of the strongest living bioelectricity generator Author de Santana, C. David Author Crampton, William G. R. Author Dillman, Casey B. Author Frederico, Renata G. Author Sabaj, Mark H. Author Covain, Raphaël Author Ready, Jonathan Author Zuanon, Jansen Author de Oliveira, Renildo R. Author Mendes-Júnior, Raimundo N. Author Bastos, Douglas A. Author Teixeira, Tulio F. Author Mol, Jan Author Ohara, Willian Author Castro, Natália Castro e Author Peixoto, Luiz A. Author Nagamachi, Cleusa Author Sousa, Leandro Author Montag, Luciano F. A. Author Ribeiro, Frank Author Waddell, Joseph C. Author Piorsky, Nivaldo M. Author Vari, Richard P. Author Wosiacki, Wolmar B. text Nature Communications 2019 2019-09-10 10 4000 1 10 http://dx.doi.org/10.1038/s41467-019-11690-z journal article 25569 10.1038/s41467-019-11690-z 0bf63512-9d52-45d8-9256-45fd2e094799 PMC6736962 31506444 3405402 Electrophorus electricus ( Linnaeus, 1766 ) Fig. 6 Lateral view of Electrophorus varii sp. nov. Holotype, Museu Paraense Emílio Goeldi MPEG 25422, 1000 mm TL. Goiapi River, Brazil Gymnotus electricus 1; Gymnoti tremuli ref. 34: 27, pl. 3; Gymnotus tremulus ref. 35: 111; Gymnotus electricus ref. 1: 427; Gymnotus regius ref. 36: 273. Diagnosis: Ten nucleotides in COI (BOL-COIfishF1/ R 1; 569- bp fragment): G(8), A(50), T (76), T (77), T (107), C(119), C(182), G(272), G(494), A(560). Ventral outline of head U-shaped, widest at terminus of branchial opening ( Fig. 2a ) and lateral-line pores 88–101 (versus ovoid, widest anterior to branchial opening, Fig. 2b ; 112–146 in E . voltai ). Distinguished by skull depressed, cleithrum lies between vertebrae 5 and 6 ( Fig. 2a ), pectoral-fin rays 32–38, and lateral-line pores 88–101 (versus skull deep, cleithrum lies between vertebrae 1 and 2, Fig. 2c , 20–28, and 124–186 in E . varii , respectively). Fig. 7 Lateral view of Electrophorus voltai sp. nov. Holotype, Museu Paraense Emílio Goeldi MPEG 15529, 1290 mm TL. Ipitinga River, Brazil Description: Species illustrated in Figs. 2 , 3 , and 5. Maximum size examined specimens 1000 mm TL (total length). Morphometric and meristic data in Supplementary Data 2. Body elongate; sub-cylindrical at pectoral girdle, progressively compressed posteriorly. Mouth superior. Scales absent. Anal and caudal fins seamlessly conjoined. Anus and urogenital papilla separated, located anterior to ventral margin of branchial opening. Head and body color brown to blackish. Clear band along body, below lateral line, variably present. Low-voltage (Sachs’ organ) EOD and high-voltage (main/ Hunter’ s organ) with head-positive monophasic waveform. Lowvoltage EOD 2.03–2.19 ms duration, n = 2 ( Fig. 4d ). High-voltage EOD 480 V at 760 mm TL, n = 1 ( Fig. 4d ). For distribution see Fig. 1a and Supplementary Data 1.