A new species of Synotaxus and the first chromosomal study on Synotaxidae, presenting a rare XY sex chromosome system in spiders (Araneae, Araneoidea) Author Souza, Lucas Henrique Bonfim Author Brescovit, Antonio Domingos Author Araujo, Douglas text Zootaxa 2017 4303 1 140 150 journal article 32529 10.11646/zootaxa.4303.1.9 f8cc580b-9034-41e9-8f2b-2f985acbb017 1175-5326 840542 20F38845-79A0-47E2-A077-7EFC9F595AF3 Synotaxus jaraguari new species Figs 1–7 Types . Holotype male from Furnas do Dionísio ( 20°10'25.83"S 54°34'40.46"W ), Jaraguari , Mato Grosso do Sul , Brazil , 14/XI/2015 , D. Araujo coll., deposited in IBSP 167041 . Paratype : one female from Toca do Ouriço ( 20°8′34″S 54°35′6″W ), Jaraguari , Mato Grosso do Sul , Brazil , 19/V/2016 , L.H.B Souza coll. ( IBSP 168350 ). Additional material examined . Brazil . Mato Grosso do Sul : Jaraguari , Furnas do Dionísio ( 20°10'25.83"S 54°34'40.46"W ), 1♂ , 14/XI/2015 , D. Araujo coll. ( IBSP 167036) ; 1♂, 14/XI/2015 , D. Araujo coll. (IBSP 167043; SEM); 1♀ juv., 17/III/2016 (IBSP 168346); 4♀ 1♂ juv. 6 juv. (IBSP 168347; IBSP 168343; IBSP 168351; IBSP 168354; IBSP 168344; IBSP 168365; IBSP 168367; IBSP 168345; IBSP 168348; IBSP 168353; IBSP 168349), all collected in 07/VII/2016 , by L.H.B. Souza coll.; Toca do Ouriço ( 20°06'04.73"S 54°33'46.23"W ), 1♀ , 19/V/2016 , L.H.B. Souza coll. ( IBSP 168352). Etymology . The specific epithet is a noun in apposition taken from the type-locality. Diagnosis . Synotaxus jaraguari n. sp. ( Fig. 1 ) resembles S. monocerus , S. itabaiana and S. siolli by the presence of a distinctive horn in the male ocular area ( Fig. 2 A–D, Agnarsson 2003 : fig. 3F–G). The males of S. jaraguari differs from these species by the shorter prongs in the patellar apophysis ( Fig. 3 B) and by the rounded base of TTA ( Figs. 2 E–F, 3A). Females have lateral atria on the epigynum, similar to that of Synotaxus itabaiana (see Santos & Rheims 2005 : fig. 17), but differ from this latter species by the anterior median border directed posteriorly ( Fig. 4 C) and by the large accessory sacs connected posteriorly to the spermathecae ( Fig. 4 D). Description . Male (IBSP 167041). Coloration: carapace yellow cream, lateral borders and large setae black, with border of the ocular median area black. Chelicerae white with teeth orange. Endites, labium and sternum white. Legs yellowish white and abdomen white. Ocular area overhanging clypeus, with one elongated and curved horn between the anterior median eyes ( Figs 2 A–D). Legs thin, with numerous setae. Abdomen elongated and pointed posteriorly, scarcely covered with setae. Carapace 1.3 long, 1.05 wide. Patella-tibia I length 5.0, II 3.0, III 1.2, IV 2.5. Abdomen used for cytogenetic study, partly destroyed. Paracymbium short with truncated apex, median apophysis large and rounded, TTA rounded distally ( Figs 2 E–F, 3A–D, 4A–B). Female ( paratype IBSP 168350). Coloration as in male, except distal area of tibia and metatarsus I–II darker. Body shape and pilosity as in male. Ocular area anteriorly triangular in dorsal view, with a small and slender curved macrosetae. Carapace 1.3 long, 1.0 wide. Patella-tibia I length 4.2, II 2.5, III 1.0, IV 2.4. Abdomen as in male. Copulatory ducts inconspicuous or apparently absent. Accessory sacs large and rounded. Spermathecae globose. Fertilization ducts long, originating from base of spermathecae ( Figs 4 C–D). Distribution . Known only from the type locality in the state of Mato Grosso do Sul , Brazil .