Two new species of Ologamasus (Acari: Mesostigmata: Ologamasidae) from Brazil with 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 4058 2 267 277 journal article 39256 10.11646/zootaxa.4058.2.8 965dad39-63e3-429c-beb2-916f4deb3d07 1175-5326 244241 4C0A5AD2-80F9-4916-9010-5A55D90096AA Ologamasus Berlese, 1888 Gamasus ( Ologamasus ) Berlese, 1888 : 194 . Gamasus ( Hologamasus ) .— Berlese, 1892 : 62 . Ologamasus ( Ologamasus ) .— Vitzthum, 1943 : 756 ; Baker & Wharton, 1952 : 73 . Ologamasus .— Berlese, 1913 : 202 ; 1914: 137; Vitzthum, 1931 : 142 ; Baker & Wharton, 1952 : 73 ; Ryke, 1962 : 160 ; Lee, 1970 : 84 ; Karg, 1976a : 185 ; Silva et al ., 2007 : 61 ; Karg & Schorlemmer, 2009 : 74 . Ologamasellus Berlese, 1914 : 139 . Synonymy by Oudemans (1939) . Ologamasellus .— Berlese, 1916 : 162 . Ologamaselus [sic].— Vitzthum, 1931 : 142. Type species: Gamasus aberrans Berlese, 1888 . Subsequent designation by Oudemans (1936) to replace Gamasus calcaratus Koch , which is the type species of Holoparasitus Oudemans, 1936 (= Ologamasus Berlese, 1906 , not Ologamasus Berlese, 1888 ). Diagnosis (adult female) . Within the Ologamasidae , Ologamasus species are characterised by having the podonotal and opisthonotal shields fused, forming a holonotal shield that is fused with the ventrianal shield; dorsal idiosomal setae aciculate and smooth, or spatulate and pilose; podonotal region of dorsum with 16–23 pairs of setae; opisthonotal region with 12–20 pairs of setae; without setae on unsclerotised integument along lateral margins of podonotal and opisthonotal shields; setae j 1 and r 3 not inserted on protuberances; one pair of presternal plates; sternal shield not fused with section of endopodal plate between coxae III and IV; peritrematic plate fused with exopodal plate posteriorly to coxa IV but not with ventrianal shield.