Electrophorus varii de Santana & Crampton & Dillman & Frederico & Sabaj & Covain & Ready & Zuanon & de Oliveira & Mendes-Júnior & Bastos & Teixeira & Mol & Ohara & Castro & Peixoto & Nagamachi & Sousa & Montag & Ribeiro & Waddell & Piorsky & Vari & Wosiacki 2019, sp. nov.

Electrophorus varii, sp. nov. de Santana, Wosiacki, Crampton, Sabaj, Dillman, Mendes-Júnior and Castro e Castro

Holotype: MPEG 25422, 1000 mm TL; Goiapi River, Marajó Island, Pará, Brazil.

Paratypes: INPA 46378, INPA 46379 (3); MHNG 2748.083; MPEG 30480 (3).

Etymology: In honor of Richard Peter Vari (1949–2016) for his contributions to ichthyology.

Diagnosis: Eleven nucleotides in COI: A(64), A(80), G(146), G (164), T (190), A(251), A(467), C(512), T (517), A(536), and C (569). Pectoral-fin rays 20–28 and lateral-line pores 124–186 (versus 32–38, and 88–101, respectively, in E. electricus). Distinguished by head narrow, Fig. 2a (versus wide, Fig. 2b, in E. voltai; distance between medial margins of contralateral dentaries at transverse through last two ventral pores 2–3 times shorter in E. varii than E. voltai, Fig. 2a, b), skull deep, cleithrum lies between vertebrae 1 and 2, Fig. 2b (versus skull depressed, cleithrum lies between vertebrae 5 and 6, in both E. electricus and E. voltai Fig. 2a, c).

Description: As for E. electricus, except as noted in Diagnosis and except clear band along body always absent. Species illustrated in Figs. 2, 3, and 6. Maximum size examined specimens 1485 mm TL. Morphometric and meristic data in Supplementary Data 2. Low-voltage EOD duration 1.24–1.78 ms (Fig. 4d), highvoltage EOD 151 V (200 mm TL) to 572 V (609 mm TL) (Fig. 4d), n = 4. For distribution see Fig. 1a; Supplementary Data 1.