Aculus sayanicus, a new species of Eriophyidae (Acari: Eriophyoidea) from grasses in Russia Author Skoracka, Anna Author Pacyna, Anna text Zootaxa 2003 149 1 10 journal article 51367 10.5281/zenodo.156185 2fc9b0b7-2253-4a5e-b744-8fe5174c4847 1175­5326 156185 Aculus sayanicus n. sp. Skoracka DIAGNOSIS: anterior lobe of prodorsal shield with three spines, typical prodorsal shield design of distinct lines bearing conical microtubercles, 8­9­rayed empodium, long, thin and tapered solenidion. FEMALE ( Figs 1­2 ) ( holotype and 8 paratypes ): Body spindleform. Body length 170 (183­235); width 60 (52­64). Gnathosoma 22 (20­23) long; dorsal pedipalpal genual seta d 14 (11­15) long; v seta (sensory peg) 2 (2) long; ep seta 3 (3); cheliceral stylets 21 (21­23) long. Prodorsal shield triangular, with rounded frontal lobe over base of chelicerae, lobe with three small spines projecting forward from under front edge. Prodorsal shield 43 (45­48) long, 46 (43­48) wide. Shield design of distinct lines, most of them bearing conical microtubercles: median line on rear ½; admedian lines entire, from anterior lobe diverging to rear margin; I submedian lines subparallel to admedian on rear ½, not reaching rear margin; II submedian lines from anterior ¼ running toward outer tubercles of sc setae, subparallel to lateral margin of shield. Tubercles of setae sc located on rear margin of shield, 4 (4­5) long, 4 (4­5) wide, 29 (28 35) apart. Setae sc 59 (48­57) long, projecting to rear. Leg I 46 (45­47) long; femur 13 (12­13) long, with seta bv 21 (18­22) long; position of seta bv 6 (5­6) from ventral, proximal margin of femur; genu 8 (7­8) long, with seta l” 40 (33­38) long, position of seta l” 4 (4) from dorsal, proximal margin of genu; tibia 11 (11­12) long, with seta l’ 14 (14­19) long; position of seta l’ 6 (6­7) from ventral, proximal margin of tibia. Tarsus 10 (9­10) long, with three setae: ft” 30 (27­36), ft’ 30 (27­30) long, u’ 11 (8­12) long; tarsal solenidion 14 (12­14) long; tarsal empodium simple, 9 (8­9)­ rayed, symmetrical, 15 (13­15) long. Leg II 45 (42­46) long; femur 13 (13) long, with seta bv 30 (30­34) long; position of seta bv 6 (5­6) from ventral, proximal margin of femur; genu 7 (6­7) long, with seta l” 24 (19­24) long; position of seta l” 4 (3­4) from dorsal, proximal margin of genu; tibia 9 (9­10) long. Tarsus 9 (8­10) long, with three setae: ft” 32 (28 33) long, ft’ 19 (14­19), u’ 10 (10­11) long; tarsal solenidion 14 (12­14) long, thin and tapered; tarsal empodium 8 (8)­rayed, symmetrical, 15 (14­15) long. FIGURE 1 : Aculus sayanicus n. sp. female: D ­ dorsal aspect; em empodium; DO ­ dorsal microtubercles; L1, L2 ­ legs I and II FIGURE 2 : Aculus sayanicus n. sp. female: CG ­ coxigenital region; IG ­ internal genitalia; PV ­ postero­ventral view. Coxae with irregular pattern of numerous dashes and microtubercles; slender sternal line present. Setae 1b 10 (10­12) apart, (15­19) long; setae 1a 8 (8­9) apart, 44 (45) long; setae 2a 22 (23­26) apart, 67 (57) long; distance between setae 1b and 1a 10 (9­10), distance between setae 1a and 2a 8 (9). Opisthosoma with 52 (45­64) dorsal annuli, 66 (58­74) ventral annuli, 7 (6­8) coxogenital annuli. Annuli with microtubercles; dorsal microtubercles bead­like, situated under folds of annuli and almost invisible on 2/3 anterior part of opisthosoma; ventral microtubercles rounded, located on annuli margin. Seta c2 57 (48­51) long, located on 9th (8th­10th) ventral annulus from coxae II; tubercles c2 51 (42­54) apart; ventral seta d 72 (57­86) long, located on 21st (21st­24th) ventral annulus; tubercles d 36 (32­38) apart; seta e 45 (43­53) long, located on 38th (34th­44th) ventral annulus; tubercles e 16 (15­17) apart; seta f 42 (38­43) long, located on 62nd (58th­70th) ventral annulus, or 5th (5th) annulus from rear; tubercles f 26 (21­27) apart. Setae h1 6 (5­6) long, 6 (6­7) apart; setae h2 105 (76­86) long, 10 (10­11) apart; distance between h1 and h2 2 (2). Genital parts 12 (11­13) long, 23 (21­24) wide, genital coverflap with 15 (10­15) longitudinal striae; setae 3a 64 (57­79) long, 17 (15­16) apart. MALE (Fig 3) ( 3 specimens ): body length 141­200; body width 49­57, spindleform. Gnathosoma 20­24 long; dorsal pedipalpal genual seta d 10­11 long; v seta (sensory peg) 2 long; ep seta 3 long; chelicerae 20­21 long. Prodorsal shield shape and design similar to that of a female, except the anterior lobe bearing two small spines projecting forward from under front edge. Shield 39­43 long; 40­55 wide. Tubercles of setae sc located on rear margin of shield, 4 long, 4 wide, 29­35 apart; setae sc 33­40 long, projecting to rear. Leg I 38 ­43 long; femur 10 long, with seta bv 16­17 long; position of seta bv 5 from ventral, proximal margin of femur; genu 6 long, with seta l” 27­30 long; position of seta l” 3­4 from dorsal, proximal margin of genu; tibia 9­10 long, with seta l’ 11­12 long; position of seta l’ 5 from ventral, proximal margin of tibia. Tarsus 8­9 long, with three setae: ft” 27 long, ft’ 23 long, u’ 6­8 long; tarsal solenidion 10­11 long; tarsal empodium simple, 7 rayed, symmetrical, 11­12 long. Leg II 36 ­38 long; femur 10 long, with seta bv 25­ 28 long; position of seta bv 4­6 from ventral proximal margin of femur; genu 5­6 long, with seta l” 18 long; position of seta l” 3­4 from dorsal, proximal margin of genu; tibia 8 long. Tarsus 8­9 long, with three setae: ft” 28 long, ft’ 13 long, u’ 7 long; tarsal solenidion 11­12 long; tarsal empodium 7­rayed, symmetrical, 12­13 long. Coxae with a pattern of dashes. Setae 1b 10­11 apart, 15 long; setae 1a 7­9 apart, 24 long; setae 2a 21­24 apart, 46 long; distance between setae 1b and 1a 7­8, distance between setae 1a and 2a 8­9. Opisthosoma with 55­58 dorsal annuli, 60­63 ventral annuli, 5 coxogenital annuli. Annuli with microtubercles; dorsal microtubercles tiny and conical, set along annuli margins; ventral microtubercles larger than dorsal ones, conical, pointed, not ahead or slightly ahead of annuli margins. Figure 3 : Aculus sayanicus n. sp. male: TP ­ prodorsal shield; GM ­ coxigenital region; DO ­ dorsal microtubercles. Seta c2 52­53 long, located on 9th ventral annulus from coxae II; tubercles c2 42­50 apart; ventral seta d 57­62 long, located on 18th ­20th ventral annulus; tubercles d 29­39 apart; seta e 43 long, located on 32nd­36th ventral annulus; tubercles e 14­18 apart; seta f 33­36 long, located on 56th­59th ventral annulus, or 5th annulus from rear; tubercles f 23­26 apart. Setae h1 4­5 long, 6 apart; setae h 2 8­10 apart; distance between h1 and h2 2. Genital parts 14­15 long, 20­23 wide; setae 3a 29­34 long, 15­19 apart; surface near the genital parts with triangular microtubercles. NYMPH ( Fig 4 ) ( 2 specimens ): body length 181­209; body width 48; vermiform. Gnathosoma 19 long; dorsal pedipalpal genual seta d 11 long; chelicerae 19. Shape and design of prodorsal shield similar to that of a female, with some exceptions: there are no microtubercles on shield, anterior lobe without spines. Shield 40­43 long, 44 wide. Tubercles of setae sc 3 long, 4 wide, located on rear margin of shield, 25­26 apart; seta sc 23­26 long. Leg I 30 long; femur 7 long, with seta bv 14 long; position of seta bv 4 from ventral, proximal margin of femur; genu 5 long, with seta l ”28 long; position of seta l” 3 from dorsal, proximal margin of genu; tibia 5 long, with seta l’ 10 long; position of seta l’ 4 from ventral, proximal margin of tibia, tarsus 6 long. Tarsal solenidion 9 long; tarsal empodium simple, 7­rayed, symmetrical, 9­10 long. Leg II 27 long; femur 8 long, with seta bv 14 long; position of seta bv 4 from ventral, proximal margin of femur; genu 4 long, with seta l” 13 long; position of seta l” 3 from dorsal, proximal margin of genu; tibia 6 long. Tarsus 7 long, with three setae: ft” 21 long, ft’ 13 long, u’ 7 long; tarsal solenidion 9 long; tarsal empodium 7­rayed, symmetrical, 9 long. Coxae with a pattern of dashes and microtubercles. Setae 1b 7­10 apart; setae 1a 9­10 apart; setae 2a 21­23 apart, 38 long; distance between setae 1b and 1a 7­8, distance between setae 1a and 2a 7­8. Opisthosoma with 54­57 dorsal annuli, 53­54 ventral annuli, 7­8 coxogenital annuli. Annuli with microtubercles; dorsal microtubercles tiny, conical with blunt top, set along annuli margins; ventral microtubercles conical, larger than dorsal ones, slightly ahead of annuli margins. Seta c2 37 long, located on 9th­10th ventral annulus from coxae II; tubercles c2 43 apart; ventral seta d 40 long, located on 19th21st ventral annulus; tubercles d 29 apart; seta e located on 31­32 ventral annulus; tubercles e 11­14 apart; seta f 26 long, located on 49th­ 50th ventral annulus, or 5th annulus from rear; tubercles f 18­24 apart. Setae h1 5 apart; setae h2 8 apart; distance between h1 and h2 2. Setae 3a 13­14 long, 8­9 apart. LARVA: not seen. TYPE MATERIAL: holotype female, 10 female paratypes , 5 males , 2 nymphs collected from Poa sibirica Roshev. (Poaceae) , in Russia , south­west part of Republic of Buryatia, Eastern Sayan Mountains, Tunka Valley, 7.2 km from Arshan locality ( 51º59’N , 102º24’E ), elevation 1800 m ., taiga; 8.09.2001; leg. A. Skoracka. FIGURE 4 : Aculus sayanicus n. sp. nymph: D ­ dorsal aspect; CG ­ coxigenital region This species was also found on the same host in Sayan Mountains, near Kitoy river ( 52º03’N , 102º23’E ), elevation 864 m . , taiga; 12.09.2001 ; leg. A. Skoracka. RELATION TO HOST PLANT : mites are vagrants on upper leaf surfaces. ETYMOLOGY: the specific name is derived from the name of the Mountains where this mite was found + icus , Greek, meaning pertaining to. REMARKS: 1) A. sayanicus is the second species of the genus Aculus described from grasses. It differs from A. bambusae Kuang, 1991 (from Bambusa sp., China ) by prodorsal shield design and prodorsal lobe shape. In A. sayanicus the median line is incomplete and there is no transverse line; the prodorsal lobe bears three spines. In A. bambusae the median line is complete and there is a transverse line joining admedian lines; the prodorsal lobe bears two spines. In addition, the two species differ in the number of I empodial rays ( 9 in A. sayanicus , 7 in A. bambusae ), number of dorsal annuli ( 52 in A. sayanicus , 37 in A. bambusae ) and length of setae: sc (48­57 A. sayanicus , 30 in A. bambusae ), 3a ( 57­79 in A. sayanicus , 22 in A. bambusae ), c2 ( 48­51 in A. sayanicus , 20 in A. bambusae ). 2) The other species collected in Eastern Sayan Mountains is Abacarus acutatus Sukhareva. It was found on Calamagrostis purpurea (Trin.) subsp. langsdorfii (Link) Tzvel. ( C. langsdorffi (Link) Trin. ) in Tunka Valley, 3.3 km from Arshan locality ( 51º57’N , 102º25’E ), elevation 1100 m , taiga; 7.09.2001. This species was described from Calamagrostis epigeios (L.) Roth in Russia ( Sukhareva 1985 ), and was also recorded from C. arundinacea (L.) Roth in Poland ( Skoracka 2000 ). C. purpurea is a new host plant for this eriophyoid mite.