Aceria rhodiolae

Aceria rhodiolae (Canestrini, 1892) Phytoptus rhodiolae Canestrini, 1892: Canestrini 1892: 722; Nalepa 1893: 294; Canestrini 1894: 803. Phytoptus sp.: Löw 1881: 5; Löw 1885: 454; Szépligeti 1890: 20. Löw (1881, 1885) mentioned ‘Phytoptus’ mites collected from ‘ mite galls ’ (‘ Phytoptocecidien ’) on R. rosea. Whereas Löw ’ s illustrations of galls are only vaguely reminiscent of those induced by A. rhodiolae, his text seems more concordant (Löw 1881), suggesting conspecificity of the mite with A. rhodiolae. Eriophyes rhodiolae (Canestrini, 1892): Nalepa 1898: 23; Nalepa 1911: 232; Nalepa 1923: 43; Ross and Hedicke 1927: 268; Nalepa 1929: 112; Kari 1932: 212; Kari 1936: 14; Julin 1936: 547; Baudyš 1938: 34; Moesz 1938: 151; Liro 1941: 4; Wahlgren 1948: 179; Liro and Roivainen 1951: 47, 125. Aceria rhodiolae (Canestrini, 1892): Roivainen 1950: 7; Leatherdale 1959: 31; Boczek 1961: 14; Buhr 1965: 1144; Farkas 1965: 23; Davis et al. 1982: 96; Amrine and Stasny 1994: 80; Bernini et al. 1995: 62; Skoracka et al. 2005: 60. [The most of these publications merely list the species, with its host, sometimes with the type of gall it produces; a few include morphological descriptions.] Diagnosis and similar species Adults can be distinguished from other Aceria species by the following combination of characters. Only one female form is known. Prodorsal shield 37 ‒ 44 long, including apically a small frontal lobe, pointed or narrowly rounded; Setae sc 27 ‒ 35 apart; first pair of submedian lines reaching posterior third of shield, where they curve inwards and then outwards (curved portion sometimes interrupted into short lines); submedian I usually branching posteriorly before its curving, roughly forming a broad, reversed ‘ Y ’ facing sc tubercles; many short ridges or nodules scattered posterolaterad submedian I, and more densely scattered laterad submedian II. Empodium with four pairs of rays. Coxal plates with conspicuous rounded ridge(s) surrounding medially setae 1a tubercles, and diagonal ridges laterad tubercles of setae 1b. Prosternal apodeme strong, slightly broadened posteriorly. Epigynial coverflap 12 – 15 long × 23 – 27 wide with 8 ‒ 12 longitudinal ridges; a pair of small, rounded lateral flaps flanking the coverflap. Opisthosoma covered by pointed microtubercles throughout, slightly larger dorsally than ventrally. Setae c2 36 – 51, d 44 – 68, e 15 – 21, f 26 – 40. Aceria destructor may be a close relative, in part based on similarity in prodorsal shield pattern, particularly submedian line I and the ridge laterally branching from it (Figure 3C, ‘ a ’) (Nalepa 1891; however, illustration in Farkas (1965) differs). Aceria rhodiolae differs from A. destructor by (Table 2): generally shorter sc setae; fewer opisthosomal annuli, and accordingly, by setae d‒f being inserted on different annuli number; a transversally narrower genital coverflap that bears fewer longitudinal ridges, with a few that are usually broken or abbreviated; posteromedian region of prodorsal shield, between sc tubercles, smooth or with few rather indistinct lineae (Figure 3) (several nodules or very short ridges present in this region in A. destructor; Figure 7; Nalepa 1891). In addition to the small V-shaped ridge crossing the median line near the posterior shield margin, often visible in A. rhodiolae (Figure 3G, ‘ c ’) and A. destructor (Figure 7, ‘ a ’), another V-shaped ridge is generally present in A. destructor, at about 15 μm from the posterior shield margin [partly discernible on Figure 7, ‘ b ’; clear on Figure 4 in Nalepa (1891); not in Farkas (1965)]. Aceria stinsonis (Keifer 1939) is moderately similar to A. rhodiolae. Based on comparison with description in the literature (Keifer 1939), A. rhodiolae may be primarily differentiated from A. stinsonis by: its longer sc; prodorsal shield with submedian I branched posteriorly; and coxisternal region ornamented with several nodules, and ridge(s) mesad seta 1a and laterad 1b (only a few scattered nodules for A. stinsonis; see also Table 2). Based on the literature (Nalepa 1895; Liro and Roivainen 1951), Aculus kochi (Nalepa and Thomas) appears similar to A. rhodiolae, particularly in the ornamentation of the dorsal shield. The main difference may be the well-developed frontal lobe of the prodorsal shield, which probably was the reason why it was assigned to Aculus by Amrine and Stasny (1994). Description (Figures 2‒6, Table 1) Female (n = 22, some measurements based on fewer specimens). Beige to pale orange (in alcohol; Figure 2A). Idiosoma somewhat vermiform 177 ‒ 327 long (depending on level of body contraction), 71 ‒ 88 wide at level of setae c2‒d. Gnathosoma (Figures 3A ‒ C, 5C) curved downward, 23 ‒ 30; palpcoxal seta ep 2.4 ‒ 3.8, palpgenual seta d 5.4 ‒ 8.3, palptarsal seta-like process v 1.7 – 2.8; cheliceral stylets 16 ‒ 21. Cheliceral retainer a broad flap bent above cheliceral stylets; these stylets largely exposed for about the proximal half of the length of palpcoxae, and covered anteriorly by the stylet sheath (Figure 3B). Prodorsal shield (Figure 3) somewhat subpentagonal (or subtriangular, if not considering the region laterad submedian lines II); 37 ‒ 44 long, 47 ‒ 59 wide, with a small frontal lobe, narrowly rounded (Figure 3A,C,E) or pointed apically (Figure 3D,F), 2.5 – 4.8 long × 6.4 – 10 wide (may appear broadly rounded in some SEM photographs, e.g. Figure 3B, possibly due to different angle of view); lobe continuous and not clearly delineated from the rest of the shield anterior margin. Setae sc typically about 50 (43 ‒ 61, exceptionally 35 on a single specimen), inserted at posterior margin of shield, projecting upwards and posterad in natural position (Figure 3B,C) and typically posterolaterad in slide-mounted specimens; sc tubercles with their basal axes transversal (hence, setae sometimes directed anteriorly on slide), setae 27 ‒ 35 apart. Shield ornamentation: median line (ridge) conspicuous for about the posterior two-thirds of shield length, and faint or absent in anterior third; a pair of short lines (ridges) often present posteriorly on each side of median line, directed anterolaterad, forming a broad ‘ V ’ (Figure 3A,E,F,G); admedian lines stretching from posterior margin of shield to about the base of frontal lobe, gradually converging anteriorly; submedian lines I subparallel to admedians, reaching posterior third of shield, where it curves mediad (inwards) and then laterad (outwards), approaching sc tubercles; curved portion of submedian lines sometimes interrupted into short ridges (Figure 3F,G). Submedian lines II running from posterolateral margins of shield to near anteromedian shield margin, at about a 90° angle from each other, and slightly curving outwards in their anterior quarter. A short ridge (‘ a ’, Figure 3C,G) (sometimes represented by a series of about four or five shorter ridges) running posterolaterad originates from submedian line I, posteriorly forming a reversed Y-shaped bifurcation, facing sc tubercles (Y-shape may not be discernible, depending on other ridges present); occasionally another ridge (or series of short ridges; ‘ b ’) running perpendicular to the previously described ridge (‘ a ’), and sometimes reaching laterally submedian line II, creating the impression of an eye-like structure (Figure 3C,G). Region between submedian lines I and II scattered with about 10 ‒ 16 short ridges or nodules; region laterad submedian line II densely scattered with 30 ‒ 38 ridges or nodules. Legs (Figures 3A,B, 4, 5) with setation normal as described for Eriophyidae (Lindquist and Amrine 1996). Leg I 38 – 45; femur 10.3 – 13.0, bv 9.6 – 12.4, position of bv 3.8 ‒ 5.0; genu 5.4 – 7.7, l” 27 – 32, position of l” 2.7 ‒ 3.6; tibia 9.0 – 11.0, l’ 9 – 13, position of l’ 1.4 ‒ 2.6; tarsus 9.5 – 11.3, ft’ 20 – 22, ft” 22 – 36, u’ 5.6 – 7.5; ω 10.0 – 11.3 without knob; empodium 7.9 – 9.0, with four pairs of rays; the two most basal pairs of rays with two (visible) secondary branches on each side, the third pair with one secondary branch, and terminal pair simple. Leg II 36 – 40; femur 10.3 – 13.4, bv 12.4 – 15.0, position of bv 3.4 ‒ 4.3; genu 4.5 – 6.2, l” 16 – 21, position of l” 2.0 ‒ 3.4; tibia 7.2 – 8.8; tarsus 9.0 – 11.1, ft’ 11 – 13, ft” 29 – 34, u’ 5.3 – 7.7; ω 9.8 – 11.0 without knob; empodium 7.0 – 10.5, with four pairs of rays, with branching as that of leg I. Apical margins of trochanter, femur, genu and tibia with spinules (more easily discerned under SEM): two dorsally on trochanters I ‒ II; two dorsally on femora I ‒ II; a few spinules laterally and ventrally on femora and genua I ‒ II; ventral spinules more tightly packed and aligned along a transversal ridge that curves medioventrally into a longitudinal ridge, which crosses genu I ‒ II entirely, and posteriorly reaches bv tubercles on femora I ‒ II; tibiae I ‒ II each with two dorsolateral ridges and a medioventral longitudinal ridge that each end apically in a spine (Figure 4). Based on SEM, femora I ‒ II apparently superficially fused mediodorsally with genu (between the two dorsal spinules), with apicolateral margins of femora sometimes extending dorsally on each side into a ridge that meets with the tubercle of genual setae l”; such ridges and fusion not apparent under light microscopy (although femoro-genual boundary may appear weak mediodorsally). Distal extension of coxal regions I and II (before connection with trochanters) with strong dorsal ridges running diagonally. Coxal region ornamented with a few conspicuous ridges, in coxal field I: one or two, moderately long, curving ridges surrounding medially tubercles of setae 1a (‘ a ’, Figure 5C); a moderately long ridge running close and parallel to coxal apodeme II, accompanied anteriorly by one or more shorter ridges laterad setae 1b tubercles (‘ b ’, Figure 5A,C); on coxal field II: a ridge running close and parallel to trochanter II margin (‘ c ’, Figure 5A,E); all these ridges are entire or interrupted into a series of s

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.