opercularis, Saraca Steindachner [F.] 1875:125 [65] [Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften. Mathematisch-Naturwissenschaftliche Classe v. 71 (1. Abth.); ref. 4220] Lago Saraca and Amazon at Villa Bella, Brazil. Syntypes: (several) MCZ 15591 (6), 15508 (2); NMW 38419 (2), 77814 (8); USNM 120434 [ex MCZ 15591] (3). On p. 65 of separate. •Valid as Biotoecus opercularis (Steindachner 1875) -- (Kullander in Reis et al. 2003:618 [ref. 27061], Staeck 2003:126 [ref. 27488], Römer 2006:1148 [ref. 28970], Staeck 2017:224 [ref. 35639]). Current status: Valid as Biotoecus opercularis (Steindachner 1875). Cichlidae: Cichlinae. Distribution: Amazon River basin, Brazil. Habitat: freshwater.