Two new species of Rykellus (Acari: Mesostigmata: Ologamasidae) from Brazil and a key to the world species of the genus Author Santos, Jandir C. Author Castilho, Raphael C. Author Silva, Edmilson S. Author De Moraes, Gilberto J. text Zootaxa 2015 3926 1 111 121 journal article 10.11646/zootaxa.3926.1.5 71045880-a3e6-4cbd-930c-fd33408f883f 1175-5326 239465 78FAB512-1F6D-46A4-9D8F-A6B1C84E3C23 Genus Rykellus Lee, 1970 Rykellus Lee, 1970 : 126 . Rykellus .— Karg & Schorlemmer, 2009 : 69 ; Karg & Schorlemmer, 2013 : 203 Type species: Cyrtolaelaps ( Gamasellus ) darglensis Ryke, 1962 , by original designation. Diagnosis (adult female) . Within the Ologamasidae , Rykellus species are characterized by having podonotal and opisthonotal shields fused along a distinct, complete V-shaped line; holodorsal shield not fused to ventrianal shield; peritrematic shield fused posteriorly with exopodal shield near coxa IV, being the connection behind stigma wider than peritreme.