festinus, Arius Ng [H. H.] & Sparks [J. S.] 2003:5, Fig. 4 [Occasional Papers of the Museum of Zoology University of Michigan No. 735; ref. 27207] Amboaboa River, near its confluence with the Mangarahara River (left bank tributary of the Sofia River), 15°50'01"S, 48°42'52"E, Madagascar. Holotype: UMMZ 239806. Paratypes: AMNH 211457 (1). Type catalog: Ferraris 2007:34 [ref. 29155], Fricke et al. 2018:61 [ref. 35805]. •Possibly valid as Ariopsis festinus (Ng & Sparks 2003) -- (Kailola 2004:126 [ref. 28108]). •Valid as Arius festinus Ng & Sparks 2003 -- (Marceniuk & Menezes 2007:16 [ref. 29031], Ferraris 2007:34 [ref. 29155], Fricke et al. 2018:61 [ref. 35805]). •Valid as Betancurichthys festinus (Ng & Sparks 2003) -- (Marceniuk et al. 2023:30 [ref. 40422]). Current status: Valid as Betancurichthys festinus (Ng & Sparks 2003). Ariidae: Ariinae. Distribution: Southwestern Indian Ocean: Amboaboa River drainage, northeastern Madagascar. Habitat: freshwater.