Electrophorus electricus (Linnaeus, 1766) 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). 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.

Published as part of de Santana, C. David, Crampton, William G. R., Dillman, Casey B., Frederico, Renata G., Sabaj, Mark H., Covain, Raphaël, Ready, Jonathan, Zuanon, Jansen, de Oliveira, Renildo R., Mendes-Júnior, Raimundo N., Bastos, Douglas A., Teixeira, Tulio F., Mol, Jan, Ohara, Willian, Castro, Natália Castro e, Peixoto, Luiz A., Nagamachi, Cleusa, Sousa, Leandro, Montag, Luciano F. A., Ribeiro, Frank, Waddell, Joseph C., Piorsky, Nivaldo M., Vari, Richard P. & Wosiacki, Wolmar B., 2019, Unexpected species diversity in electric eels with a description of the strongest living bioelectricity generator, pp. 1-10 in Nature Communications 10 (4000) on page 6, DOI: 10.1038/s41467-019-11690-z, http://zenodo.org/record/3405402

{"references": ["1. Linnaeus, C. Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Laurentii Salvii, Holmiae. 12 th ed. v. 1 (pt 1): 1 - 532 (1766)."]}