Stauffer, McCrary & Black, 2008
Multiple species of this group have been identified and verified by genomic and mitochondrial DNA evidence in the volcanic crater lake Apoyo and another Nicaraguan crater lake, Xiloá. The genetic evidence from Apoyo supports a hypothesis that the six known species of the lake evolved via sympatric speciation. A few to perhaps several dozen species fitting the biological species concept are considered to exist among what has historically been called A. citrinellus, the great majority of which have not been described to date. The nine most recently described members of this species complex are considered endemic to their respective small, volcanic crater lakes.
- Stauffer JR, Jr., McCrary JK, & Black KE (2008): Three new species of cichlid fishes (Teleostei: Cichlidae) from Lake Apoyo, Nicaragua. PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 121(1):117–129
- Geiger MF, McCrary JK, & Stauffer JR, Jr. (2010): Description of two new species of the Midas cichlid complex (Teleostei:Cichlidae) from Lake Apoyo, Nicaragua; PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 123(2):159–173
- Geiger MF, McCrary JK, Schliewen U (2010): Not a simple case – A first comprehensive phylogenetic hypothesis for the Midas cichlid complex in Nicaragua (Teleostei: Cichlidae: Amphilophus); Molecular Phylogenetics and Evolution 56:1011-1024 "Archived copy" (PDF). Archived from the original (PDF) on 2011-10-03. Retrieved 2011-01-01.
- FishBase (2006) Eds. Froese, R. and D. Pauly. World Wide Web electronic publication. fishbase.org version (07/2006)
- "Mojarras de Apoyo a Museo Smithsonian" (in Spanish) 
- "Hallan Nuevas Mojarras" (in Spanish)
- "El Nuevo Charco de Suenos de Darwin" (in Spanish)
- "The Little Apoyo Cichlid, Amphilophus astorquii"
- "Video of endemic Amphilophus cichlids in Laguna de Apoyo, Nicaragua" 
- "Amphilophus astorquii in a multspecies school" 
- "Nesting Amphilophus globosus photographed" 
- "Chancho Cichlid"