A key to the species of Protogamasellus (Acari: Ascidae), with a new species from the Brazilian Pantanal Author Yamada, Mariana Departamento de Entomologia e Acarologia, Escola Supeior de Agricultura “ Luiz de Queiroz ” (ESALQ) - Universidade de São Paulo (USP), 13418 - 900 Piracicaba, São Paulo, Brazil. marianayamada @ usp. br; https: // orcid. org / 0000 - 0002 - 6150 - 0397 Author De Moraes, Gilberto J. Departamento de Entomologia e Acarologia, Escola Supeior de Agricultura “ Luiz de Queiroz ” (ESALQ) - Universidade de São Paulo (USP), 13418 - 900 Piracicaba, São Paulo, Brazil. marianayamada @ usp. br; https: // orcid. org / 0000 - 0002 - 6150 - 0397 & CNPq Researcher; Departamento de Entomologia e Acarologia, Escola Superior de Agricultura “ Luiz de Queiroz ” (ESALQ) - Universidade de São Paulo (USP), 13418 - 900 Piracicaba, São Paulo, Brazil. text Zootaxa 2020 2020-06-18 4801 2 343 354 journal article 21640 10.11646/zootaxa.4801.2.8 6fd34dba-e79f-4cdc-9e5a-719ffd2ae517 1175-5326 3900519 8EA3ABA3-C435-4BCE-AC26-3C2323B8B03A Protogamasellus sigillophorus Mineiro, Lindquist & Moraes, 2009 Protogamasellus sigillophorus Mineiro, Lindquist & Moraes, 2009: 26 ; Moraes et al ., 2016: 126 . Morphology (females, five specimens measured). Gnathosoma. Fixed cheliceral digit 33 (33–36) long, with 11–13 teeth, a large offset subapical tooth and setiform pilus dentilis . Movable digit 35 (32–37), with two teeth; epistome anteriorly subtriangular, with serrate margin. Deutosternum with a smooth transverse line, followed by six transverse lines with 1–4 denticles each. Corniculi stout, spine-like, subparallel to each other. Dorsal idiosoma. Idiosoma 288 (279–303) long and 132 (129–134) wide at level of r 3. Podonotal shield with a continous transverse line at level of z 6; without scleronoduli; 140 (134–146) long and 100 (96–104) wide at level of j 5; with 17 pairs of setae, four pairs of poroids and a pair of solenostomes setae j 2 transversely aligned with j 1 and z 1.Unsclerotised lateral cuticle with five pairs of setae ( s 2, r 2– r 5). Opisthonotal shield with a continuous transverse line at level of J 1; 145 (140–150) long and 65 (63–67) wide at level of J 2; with 15 pairs of setae, six pairs of poroids and two pairs of solenostomes. Unsclerotised lateral cuticle with seven pairs of setae ( R 1 – R 6 and UR ). Setal lengths: j 1 25 (23–27), j 2 11 (10–11), j 3 11 (10–11), j 4 13 (12–13), j 5 11 (10–12), j 6 13 (11–15), J 1 12 (13–11), J 2 13 (11–15), J 3 14 (13–14), J 4 13 (12–14), J 5 10 (9–11), z 1 11 (10–11), z 2 12 (10–13), z 3 14 (12–15), z 4 13 (12–14), z 5 15 (14–16), z 6 17 (16–18), Z 1 17 (14–19), Z 2 17 (16–18), Z 3 19 (17–20), Z 4 19 (18–22), Z 5 30 (29–30), s 1 12 (10–13), s 2 13 (11–14), s 3 11 (10–11), s 4 15 (14–15), s 5 16 (14–17), s 6 18 (17–19), S 1 14 (13–14), S 2 13 (11–14), S 3 12 (11–13), S 4 15 (13–17), S 5 15 (14–16), r 2 15 (13–17), r 3 15 (14–16), r 4 13 (11–14), r 5 10 (9–11), R 1 9 (7–10), R 2 11 (9–12), R 3 10 (8–11), R 4 10 (8–11), R 5 11 (10–12), UR 9 (8–10); setae aciculate and smooth, except J 4, Z 5 and S 5, sparsely barbed. Ventral idiosoma. Base of tritosternum 26 (24–27) long and 8 (7–9) wide proximally; laciniae 51 (50–52), separated for about 80% of their total length, pilose. Pre-sternal area punctate, pre-sternal platelets absent. Sternal shield smooth, with anterior margin deeply emarginated; 76 (74–78) long and 65 (64–66) wide at level of st 2; with three pairs of simple setae and three pairs of poroids; distances st 1– st 3 56 (53–58), st 2– st 2 42 (39–44). Metasternal plates indistinguishable, fourth pair of sternal setae ( st 4) on unsclerotised cuticle. Genital shield smooth, bearing st 5, with posterior margin truncate; 59 (53–64) long and 23 (19–26) wide at widest level; distance st 5– st 5 23 (21–24); poroids iv 5 on unsclerotised cuticle. With two pairs of rounded metapodal platelets. Ventrianal shield with anterior margin arched, with 2–3 transverse and arched lines between Jv 2 and anal opening; 92 (87–97) long and 71 (68–73) wide at widest level; with three pairs of setae ( Jv 2, Jv 3 and Jv 5) in addition to circumanals; Jv 1, Jv 4 and Zv 1on unsclerotised cuticle; para-anal inserted at level of anterior anal margin; anal opening 15 (14–16) long. Endopodal plates represented by lightly sclerotised strips alongside coxae III–IV. Exopodal plates reduced to triangular plates between the coxae II–III and III–IV. Setal lengths: st 1 14 (12–15), st 2 16 (14–17), st 3 16 (15–17), st 4 13 (11–14), st 5 11 (10–12), Jv 1 9 (8–10), Jv 2 13 (11–14), Jv 3 9 (7–11), Jv 4 9 (7–10), Jv 5 20 (19–21), Zv 1 11 (10–12), para-anal 15 (14–16), post-anal 30 (29–31); setae aciculate and smooth, except Jv 5 and post-anal, sparsely barbed. Peritreme and peritrematic plate. Peritreme short, extending anteriorly to level of r 3; petritrematic plate narrow posteriorly. Spermathecal apparatus. Indistinct. Legs. Lengths of legs (not including pretarsus): I: 272 (267–276); II: 165 (162–167); III: 137 (134–139); IV: 206 (202–210). Setation (legs I IV): coxae: 2, 2, 2, 1; trochanters: 1 0/1, 1/2 1; 1 0/1, 0/2 1; 1 0/1, 0/2 1; 1 0/1, 0/2 1; femora: 2 3/1, 2/2 2; 2 3/1, 2/2, 1; 1 2/1, 1/0 1; 1 2/1, 1/0 1; genua: 2 3/2, 3/1 2; 2 3/1, 2/1 2; 2 2/1, 2/0 1; 2 2/1, 3/0 0; tibiae: 2 3/2, 3/1 2; 2 2/1, 2/1 2; 2 1/1, 2/1 1; 2 1/1, 3/1 1; tarsi: I: not counted, 18, 18, 18. All legs with pretarsus containing claws and pulvillus. Adult male. Not found. Material examined. Five females from soil of natural vegetation of the Pantanal , on September 2018 ; two females from the same substrate, on March 2019 ; 50 females from soil of soybean field , on September 2018 ; 36 females from soil of corn field , on March 2019 ; 44 females from soil of sorghum field , on March 2019 ; two females from pasture soil , on September 2018 ; two females from the same substrate, on March 2019 ; two females from the same substrate, on June 2019 . Remarks. The specimens collected agree well with the original description of the species.