Key to identification of Monospilus species of the world 1. Carapace with lateral projections.................................... M. daedalus (Kotov & Sinev 2011) —East Asia - Carapace without lateral projections.......................................................................2 2. Postabdominal claw armed with distalmost basal spine robust, while proximalmost basal spine short and thin............3 - Postabdominal claw armed with both distalmost and proximalmost basal spine robust.......... M. dispar —Cosmopolitan? 3. Postabdominal claw on the postabdomen armed with two pectens...............................................4 - Postabdominal claw with a single saw-shaped pecten......................... M. macroerosus sp. nov. — Central Brazil 4. Postabdominal claw with not sharp tip; proximalmost basal spine length about 1/5 of the length of the distalmost basal spine; labral keel with three rows of setulae.................................... .. M. brachyspinus sp. nov. — Central Brazil - Postabdominal claw with sharp tip; proximalmost basal spine longer than half of distalmost spine length; labral keel with one row of setulae....................................................... Monospilus sp. —Southern South America

Published as part of Sousa, Francisco Diogo R., Elmoor-Loureiro, Lourdes M. A. & Panarelli, Eliana A., 2017, The amazing diversity of the genus Monospilus Sars, 1862 (Crustacea: Branchiopoda: Aloninae) in South America, pp. 467-492 in Zootaxa 4242 (3) on page 486, DOI: 10.11646/zootaxa.4242.3.3, http://zenodo.org/record/376914