Aceria cortii Amrine & Stasny, 1994

Flechtmann, C. H. W., Arana, M., Ciarrocchi, F., Chetverikov, P. E. & Amrine Jr., J. W., 2015, Rediscovery and redescription of two eriophyid mites (Acari, Prostigmata, Eriophyidae) from Baccharis salicifolia (Asteraceae), from Argentina with remarks on the eriophyoid coverflap base, Acarologia 55 (4), pp. 387-396 : 388-389

Aceria cortii Amrine & Stasny, 1994

( Figs. 1 , 2 )

Replacement name for Aceria baccharidis (Corti, 1917) , preoccupied by homonymy of Aceria baccharidis ( Kieffer & Herbst, 1911) ( Flechtmann, 1983) .

Eriophyes baccharidis Corti, 1917 – objective synonym of Aceria cortii .

Aceria cortii Amrine & Stasny, 1994: 37 .

Female — (n = 6) Body elongate, 119 – 218, 39 – 73 wide.

Gnathosoma projecting down, pedipalp coxal seta (ep) 4, dorsal pedipalp genual seta (d) 3 – 5, simple, cheliceral stylets 14 – 16. Prodorsal shield 23 – 26, 32 – 46 wide, frontal lobe absent; shield design with median and admedian lines extending over entire shield length, submedian lines on posterior half variously inclined and converging posteriorly. Scapular tubercles 23 – 29 apart, scapular setae (sc) 22 – 33 long, directed backwards and extending over 12 – 18 opisthosomal dorsal annuli.

Coxal plates – smooth; anterolateral seta on coxisternum I (1b) 6 – 9, 11 – 13 apart, proximal setae on coxisternum I (1a) 18 – 22, 8 – 9 apart, proximal setae on coxisternum II (2a) 26 – 38, 19 – 25 apart. Prosternal apodeme present, 5, straight, bifurcate terminally.

Legs with usual series of setae. Leg I 26 – 28, femur 7 – 9, basiventral femoral seta (bv) 5 – 7; genu 3 – 4, antaxial genual seta (l") 18 – 23; tibia 4 – 6, paraxial tibial seta (l’) 3 – 4, placed on proximal half; tarsus 5 – 6, paraxial fastigial tarsal seta (ft’) 4 – 9, antaxial fastigial tarsal seta (ft") 12 – 19, paraxial unguinal tarsal seta (u’) 3 – 4, tarsal solenidion curved, slightly knobbed, 7, tarsal empodium 5, 5- rayed, distallly bifurcate. Leg II 24 – 26; femur 7, bv 5 – 7; genu 4, l" 5 – 10; tibia 4 – 6; tarsus 5 – 6, ft’ 5, ft" 16 – 18, u’ 4, solenidion 7 – 8, empodium 5, 5-rayed.

Opisthosoma dorsally with 60-68 annuli, microtuberculate except for the caudal 5-7 annuli which are devoid of microtubercles. Microtubercles small, bead-like and pointed posteriorly. Opisthosoma circular in cross-section. Total ventral annuli 50- 62, microtuberculate. Lateral setae (c2) 19-26, on ventral annulus 3-5 counting from first complete transversal anulus behind genitalia. Ventral seta I (d) 15 – 20, 28 – 43 apart, on ventral annulus 12 – 16 from genitalia rear border; ventral seta II (e) very short, 3 – 5, 16 – 17 apart, on annulus 23 – 32; ventral seta III (f) 26 – 30, 23 – 33 apart, on annulus 40 – 57 or 6 – 7 th from rear. Caudal setae (h2) 53 (probably broken) – 99; accessory setae (h1) robust, 4.

Genitalia 14 – 11, 18 – 22 wide, coverflap with 8- 10 conspicuous longitudinal scorings in some specimens, apparently smooth in other.

Male — not seen.

Larva (n = 2). Body 53 long; prodorsal shield 22 long, no shield design discernible; opisthosoma with 44 dorsal annuli, microtuberculate, except for the caudal 5.

Protonymph (n = 4) Body 89 – 135; prodorsal shield 22 – 25, shield design similar to female; opisthosoma with 60-61 annuli, microtuberculate, except for the 5 caudal annuli.

Marerial examined — 24 females, 8 protonymphs, 2 larvae, recovered from dissected leaf galls of Baccharis salicifolia (Ruiz. & Pav.) Pers. Asteraceae , and one female vagrant on leaf of the same plant, Cordoba, Argentina , GPS 33°10’S, 64°20’W, collected by M. Arana, October 2014, on eight microscopic preparations in the collection of the Departamento de Entomologia e Acarologia, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de Sªo Paulo, Piracicaba, Sªo Paulo, Brazil . Duplicates are in the biological collection of Departamento de Ciencias Naturales , Universidad Nacional de Rio Cuarto, Córdoba, Argentina .

Remarks — One of the females, apparently senile, had a fully grown larva and two eggs inside

Acarologia 55(4): 387–396 (2015)

her body.

Relation to host — This species is a gall inducer on leaves and young stems of B. salicifolia; the galls are glabrous and globose, 1-2 mm in diameter, yellowish, hollow ( Fig. 3 ).

Kieffer & Jorgensen (1910, p. 374) referred to "Eriophyidengallen" on Baccharis salicifolia from Mendoza, Argentina. Kieffer & Herbst (1911, p. 703) refer to the galls mentioned in the previous paper, however inform that they were collected from Baccharis subulata D. Don ex Hook. & Arn. (= Baccharis juncea (Cass.) Desf.), and which they attribute to Eriophyes baccharidis n.sp., but, they only described the gall. Amrine & Stasny (1994) made a new combination, transferring the mite species to Aceria baccharidis and updated the host plant name to Baccharis juncea. At this point we do not have sufficient information to further comment on Aceria baccharidis : there is no description nor figure of the mite, no material (gall or mite) from B. juncea exists and Amrine & Stasny (1994) maintained this species distinct from A. cortii . Specimens from Baccharis juncea in Mendoza, Argentina need to be found and carefully described. If conspecific with Aceria cortii , then Aceria baccharidis ( Kieffer & Herbst, 1911) becomes the senior synonym.

Figures

FIGURE 1: Aceria cortii Amrine & Stasny, 1994 – Female. AV, anterior ventral aspect; DA, dorsal anterior aspect; DC, dorsal caudal aspect; E, empodium; IGF, internal genital structures of female; L1, leg I; L2, leg II.

FIGURE 2: Aceria cortii Amrine & Stasny, 1994 – Female. Differential contrast image of dorsal, top, and ventral, bottom.

FIGURE 3: Baccharis salicifolia: top, leaf galls, bottom, twig galls elicited by Aceria cortiiAmrine & Stasny.