Aceria wassalberti, Ripka, Géza, 2016

Ripka, Géza, 2016, A new Aceria species (Acari: Prostigmata: Eriophyoidea) from Minuartia frutescens (Caryophyllaceae) in Hungary, Zootaxa 4189 (1), pp. 165-173 : 166-171

Aceria wassalberti n. sp.

( Figs 1–3 )

Description. FEMALE (n= 10). Body dirty whitish (cinereous) yellow (except white nymphs), vermiform, 211 (160–225), 70 (67–71) wide, 70 thick. Gnathosoma 22 (21–25), projecting obliquely downwards; chelicerae 20 (19–22), dorsal palp genual setae d 8 (7–8), unbranched; pedipalp coxal setae ep 2 (2–3). Prodorsal shield 33 (32– 35), 52 (50–53) wide, half circle, with a short acuminate frontal lobe 2 (2–3) over cheliceral base; shield pattern composed of a light incomplete median line on rear third (⅓–½), two light, incomplete admedian lines beginning close to posterior margin of the shield, slightly diverging to rear margin. All lines interrupted, partly granular and fading towards frontal lobe. Ahead of scapular tubercles a granular transversal line between admedian and shield margin at ¼ of posterior margin of prodorsal shield. Several granules and dashes are between median and admedian lines, and admedian lines and shield margin. The ornamentation of prodorsal shield is considerably variable, e.g. number, size and position of granules (see Figs 1 and 2 ). Tubercles of scapular setae sc on rear shield margin, 23 (23–25) apart, diverging, scapular setae sc 23 (23–30), directed rearwards. Fine granules laterally in rows between shield margin and dorsal coxae of legs I and II. Legs with all usual segments and setae present. Leg I 33 (31–37), femur 10 (9–10), basiventral femoral seta bv 11 (10–12), genu 5 (5–6), antaxial genual setae l″ 28 (28–31), tibia 7 (7–8), paraxial tibial setae l ′ located at ⅓ (⅓–¼) from dorsal base, 7 (6–8), very fine, tarsus 8 (7–8), paraxial, unguinal tarsal setae u ′ 5 (4–6), solenidion ω 9 (9–10), slightly tapering and curved, distally knobbed, empodium simple, bilaterally symmetrical, 7 (7–8), 5-rayed. Leg II 31 (28–32), femur 9 (9–10), basiventral femoral setae bv 10 (10–12), genu 5 (5), antaxial genual setae l″ 10 (10–12) very fine, tibia 7 (5–7), tarsus 7 (6–7), paraxial, unguinal tarsal setae u ′ 4 (4–5), solenidion ω 9 (8–10) subequal with solenidion ω on leg I, curved, distally knobbed, empodium simple, bilaterally symmetrical, 7 (7–8), 5-rayed. Minute spinules distally on femora, genua and tibiae on both leg pairs. Segment border dorsally between femur and genu is slightly discernible, faint or missing on both leg pairs. Coxae I with several longitudinal lines, dashes and granules, coxae II with few lines of granules; setae 1b 8 (7–11), tubercles 1b 14 (12–15) apart; setae 1a 19 (17–22), tubercles 1a 11 (11–12) apart, setae 2a 38 (37–42), tubercles 2a 29 (27–29) apart. Subcapitular plate anteriorly rounded, with faint lines and granules. Prosternal apodeme distinct 10 (5–10), forked. Coxigenital area with 5–8 microtuberculate semiannuli. Opisthosoma with 60 (56–62) dorsal semiannuli, 62 (58–63) ventral semiannuli. Dorsal and ventral semiannuli microtuberculate. Dorsally elongate, ventrally round and slightly pointed microtubercles close to rear annular margin, except for 4–5 ventral semiannuli near anal lobes, which are elongate and linear. Caudal lobe normal in size and shape. Opisthosomal setae c2 53 (52–55), on annulus 10 (9–11), 65 (62–65) apart. Setae d 58 (51–58), on annulus 23 (22–25), 44 (42–45) apart; setae e 12 (12–13), on annulus 37 (35–39), 23 (23–25) apart; setae f 30 (28– 33), on annulus 55 (52–58), or 6 (6–7) from rear, 29 (27–29) apart, all very fine towards apex. Setae h2 65 (65–77), 13 (12–13) apart; setae h1 4 (4–5), 8 (7–8) apart. Genital plate 15 (15–20), 28 (26–28) wide, genital coverflap with 14 (13–14) longitudinal parallel striae. Setae 3a 17 (16–20), 22 (20–23) apart.

MALE (n= 5). Similar to female, 125–170, 57–60 wide, 57 thick. Gnathosoma 17–22, projecting obliquely downwards; chelicerae 15–16, dorsal palp genual setae d 4–6, unbranched, pedipalp coxal setae ep 1–2. Prodorsal shield 28–30, 46–50 wide, half circle, with a short acuminate frontal lobe, shape and ornamentation similar to female. Tubercles of scapular setae sc on rear shield margin, 21–23 apart, setae sc 19–21, directed rearwards. Legs with all usual segments and setae present. Fine granules laterally in rows between shield margin and dorsal coxae of legs I and II. Leg I 27–30, femur 8–9, basiventral femoral setae bv 8–9, very fine, genu 5, antaxial genual setae l″ 23–26, tibia 6–7, paraxial tibial setae l ′ located at ⅓ from dorsal base, 6, very fine, tarsus 6–7, unguinal tarsal setae u ′ 3, solenidion ω 7–8, slightly curved, distally knobbed, empodium simple, bilaterally symmetrical, 6–7, 5- rayed. Leg II 25–27, femur 8–9, basiventral femoral setae bv 8–10, very fine, genu 4–5, antaxial genual setae l″ 9– 12, very fine, tibia 5, tarsus 5–6, unguinal tarsal setae u ′ 4, solenidion ω 7–8, slightly curved, tapering, distally knobbed, empodium simple, bilaterally symmetrical, 5–6, 5-rayed. Minute spinules distally on femora, genua and tibiae on both leg pairs. Segment border dorsally between femur and genu is slightly discernible, faint or missing on both leg pairs. Coxae I with several longitudinal lines, dashes and granules, coxae II with few lines of granules; anterolateral setae on coxa I, setae 1b 10, tubercles setae 1b 11–12 apart, proximal setae on coxa I, setae 1a 14–17, tubercles setae 1a 10–12 apart, proximal setae on coxa II, setae 2a 25–30, very fine, tubercles setae 2a 23–25 apart. Prosternal apodeme 4–5, forked. Coxigenital area with 6–9 microtuberculate semiannuli. Opisthosoma with 48–55 dorsal, 50–52 ventral semiannuli. Microtuberculate dorsal and ventral semiannuli. Dorsally elongate, ventrally minute, round and slightly pointed microtubercles set on rear annular margin, except for 4–5 ventral semiannuli of anal lobes, which are elongate and linear. Caudal lobe normal in size and shape. Setae c2 33–42, on annulus 9–11, 52–53 apart; setae d 38–43, on annulus 18–20, 35–38 apart; setae e 10, on annulus 29–31, 20–22 apart; setae f 23– 25, on annulus 45–47, or 5 from rear, 23–25 apart. Setae h2 52–55, 10–12 apart; setae h1 3–4, 5–6 apart. Genitalia 12–15, 20–22 wide, with many minute granules, setae 3a 10–11, 17–19 apart.

NYMPH (n= 4). White, vermiform, 152–180, 57–61 thick. Prodorsal shield 29–30, 42–46 wide. Gnathosoma 17–20, chelicerae 11–12. Tubercles of scapular setae sc on rear shield margin, 17–21 apart, setae sc 13–19, pointing rearwards. Leg I 22–25. Leg II 20–22. Anterolateral setae on coxa I, setae 1b 5–6, tubercles setae 1b 11–12 apart, proximal setae on coxa I, setae 1a 10–11, tubercles setae 1a 9–10 apart, proximal setae on coxa II, setae 2a 17, very fine, tubercles setae 2a 22–23 apart. Prosternal apodeme 4–5, forked. Opisthosoma with 52–61 dorsal, 47–49 ventral semiannuli. Dorsal and ventral semiannuli with minute microtubercles like dots. Setae c 2 27– 31, on annulus 9, 50–53 apart; setae d 22–27, on annulus 19, 34–35 apart; setae e 7–8, on annulus 28–30, 20 apart; setae f 19–20, on annulus 42–44, or 5–6 from rear, 23–27 apart. Setae h2 45–47, 10–11 apart; setae h1 3, 6 apart. Setae 3a 5–9, 10–12 apart.

Type host plant. Sandwort or stitchwort, Minuartia frutescens (Kit.) Tuzson (Caryophyllaceae) ; a Carpathian- Pannonian perennial herb endemic to Hungary. It is a characteristic, threatened and protected species of dry silicate rock vegetation, in Hungarian szilikát-sziklagyep.

Relation to the host plant. The mite was found in all developmental stages on the leaf sheaths, flowers, involucral bracts, calices, petals, young fruits and leaves. No damage was caused.

Type locality. Boldogkő vára, Boldogkőváralja, Borsod-Abaúj-Zemplén county, North-East Hungary, 48°20'45" N, 21°13'56" E, 245 m above sea level. The host plant species, M. frutescens , grows in an inland dry rock vegetation of the region developed on silicate rock soil ( Borhidi 2003).

Type material. Holotype: female (circled with black ink) with 7 females, 3 males and 2 nymphs paratype on the same slide (slide # 1368a), coll. G. Ripka, 23.v.2015. Paratypes: 5 females, 3 males, 2 nymphs, and 1 unidentified female of (Acariformes: Eriophyidae ) and 1 unidentified female (Acariformes: Phytoptidae ) (slide # 1368b), 2 females, 4 males and 3 nymphs (slide # 1368e); 11 females, 2 nymphs and 1 unidentified female (Acariformes: Eriophyidae ) (slide # 1368c) coll. G. Ripka. Holotype (slide # 1368a) and paratypes (slides # # 1368b, c) deposited in the Department of Pest Management Development and Coordination, Directorate of Plant Protection, Soil Conservation and Agri-environment, National Food Chain Safety Office , Budapest, Hungary, paratypes (slide # 1368e) deposited in the Hungarian Natural History Museum , Budapest, Hungary.

Etymology. The species is named after Albert Wass (1908-1998), one of the most widely-read Hungarian writers. He leaved in Transylvania, Hungary, Rumania (after the First World War) and in Germany and USA (after the Second World War). His historical novels are very popular in Hungary.

Differential diagnosis and remarks. Until now, no eriophyid mite species has been reported on the representatives of the genus Minuartia L. The new species described herein shows similarities with some European nominal Aceria species living on caryophyllaceous hosts: Aceria belarexi Ripka, 2016 , Aceria cerastii ( Nalepa, 1892) , Aceria colocense Ripka, 2013 , Aceria dianthi ( Lindroth, 1904) , Aceria feketeistvani Ripka, 2016 , Aceria gypsophilae Roivainen, 1950 , Aceria moehringiae ( Lindroth, 1899) and Aceria silenes ( Liro, 1940) ( Nalepa 1892; Lindroth 1899; Lindroth 1904; Liro 1940; Roivainen 1950; Liro & Roivainen 1951; Ripka 2013, 2016). Each of these species are compared below, and their collection data are summarised in Table 1 .

Species Host species Habitat and alterations World distribution Aceria belarexi has distally rounded solenidia (knobbed in A. wassalberti n. sp.), narrowly separated coxae I and lacks the sternal apodeme (forked prosternal apodeme (5–10) in A. wassalberti n. sp.), setae e, setae 3a and setae h 2 18–28, 25–30 and 81–105 long, respectively (12–13, 16–20 and 65–77 in A. wassalberti n. sp., resp.).

Aceria cerastii has its prodorsal shield subtriangular (half circle in A. wassalberti n. sp.), an anteriorly rounded prodorsal shield without a frontal lobe (acuminate frontal lobe in A. wassalberti n. sp.), tarsus 1.5 times longer than tibia (length of tarsus same as tibia in Aceria wassalberti n. sp.) and empodium 4-rayed ( Nalepa 1892) (5-rayed in A. wassalberti n. sp.).

Aceria colocense has its prodorsal shield subtriangular (half circle in A. wassalberti n. sp.), coxae with small granules (coxae with longitudinal lines and dashes in A. wassalberti n. sp.), genital coverflap with 11–13 uneven striae (13–14 in A. wassalberti n. sp.), and setae f 20–24 long (28–33 in A. wassalberti n. sp.).

Aceria dianthi has 14–16 striae on the genital coverflap (13–14 striae in A. wassalberti n. sp.), setae h2 45 long (65–77 in A. wassalberti n. sp.), 70–80 annuli (56–63 in A. wassalberti n. sp.), and setae 3a 9 long (16–20 in A. wassalberti n. sp.) ( Lindroth 1904; Liro & Roivainen 1951).

Aceria feketeistvani differs as follows: length of scapular setae sc 45–70 (22–30 in A. wassalberti n. sp.), genital coverflap with 9–12 striae (13–14 in A. wassalberti n. sp.), empodium 7-rayed (5-rayed in A. wassalberti n. sp.), solenidion distally rounded (knobbed in A. wassalberti n. sp.), opisthosoma with 73–87 annuli (56–63 in A. wassalberti n. sp.), and length of setae e 37–52 (12–13 in A. wassalberti n. sp.).

Aceria gypsophilae differs by having a short and unforked sternal line, setae 3a 30 long, and 10 striae on the genital coverflap ( Roivainen 1950). In contrast, A. wassalberti n. sp. has a distinct and forked prosternal apodeme (5–10), considerably shorter setae 3a (16–20), and 13–14 striae on the genital coverflap.

Aceria moehringiae (Lindroth) has a 6-rayed empodium (5-rayed in A. wassalberti n. sp.) and 90 annuli (56– 63 in A. wassalberti n. sp.) ( Lindroth 1899).

Aceria silenes (Liro) differs by the pattern of the prodorsal shield, which lacks lines in A. silenes (with lines in A. wassalberti n. sp.), and the width and thickness of the idiosoma 56–60 (67–71 in A. wassalberti n. sp.) ( Liro 1940). Furthermore, setae c2 are 52–55 and setae d are 51–58, both being significantly longer than the scapular setae sc which are 23–30 in A. wassalberti n. sp. (both setae slightly longer than setae sc in A. silenes ). The species are also separated on biological characteristics, as A. silenes causes bud deformation and shoot stunting on Silene rupestris (versus no damage caused by A. wassalberti n. sp.).

Finally, Aceria ankarensis Denizhan, Monfreda, Cobanoglu & de Lillo was described from Dianthus chinensis L. in Turkey ( Denizhan et al. 2006) and might be expected to be present on the same host plant in Hungary. The new species differs from A. ankarensis in having a distinct and forked prosternal apodeme (prosternal apodeme not well defined in A. ankarensis ), the length of setae e, 12–13 (59–68 in A. ankarensis ), length of setae f, 28–33 (42– 50 in A. ankarensis ) and the length of setae 3a 16–20 (54–60 in A. ankarensis ).

Figures

FIGURE 1. Aceria wassalberti n. sp., semischematic drawings. Scale bars: 20 µm for AL; 18 µm for AD, 21 µm for CG, 24 µm for LO; 14 µm for IG; 16 µm for L 1, 22 µm for PM; 12 µm for GM; 4 µm for em.

FIGURES 2 – 3. SEM micrographs of Aceria wassalberti n. sp. (2) anterodorsal view of probably a female and (3) ventrolateral view of anterior region of male.

Tables

TABLE 1. Eriophyoid mite species currently described on family Caryophyllaceae, their host species, habitat, symptoms and current distribution.

Aceria ankarensis Denizhan, Monfreda, Cobanoglu et de Lillo	Dianthus chinensis L.	On leaves. No damages	Turkey
Aceria belarexi Ripka	Gypsophila paniculata L.	In the leaf sheaths on the stem and in between the involucral bracts of inflorescence and axil. No damages	Hungary
Aceria cerastii (Nalepa)	Cerastium triviale L.	Bud deformation, erineum	France
Aceria colocense Ripka	Silene borysthenica (Gruner) Walters	In the leaf sheaths and buds, underside and upper side of the stipules, bracts and leaves, on the flower buds, and peduncles. No damage.	Hungary
Aceria dianthi (Lindroth)	Dianthus deltoides L.	Vagrant, stunting	Finland
Aceria feketeistvani Ripka	Petrorhagia prolifera (L.) P.W. Ball et Heywood	In the leaf sheaths. No damages	Hungary
Aceria georghioui Keifer	Dianthus sp.	In the leaf axils. Discoloration	Cyprus
Aceria gypsophilae Roivainen	Gypsophila fastigiata L.	Vagrant	Sweden
Aceria moehringiae (Lindroth)	Moehringia lateriflora (L.) Fenzl) Moehringia ciliata (Scop.) Dalla Torre (mentioned as Moehringia polygonioides M. & K.)	Chlorosis	Finland
Aceria paradianthi Keifer	Dianthus sp.	Between the leaf bases and stems. Stunting and basal sprouting	California, USA
Aceria silenes (Liro)	Silene rupestris L.	Shortening of internodes, twig and flower deformation	Finland
Aceria wassalberti Ripka n. sp.	Minuartia frutescens (Kit.) Tuzson	In the leaf sheaths, in flowers, on involucral bracts, calices, petals, young fruits and leaves. No damages	Hungary
Aculus parvensis Manson	Stellaria parviflora Banks & Sol. ex Hook. f.	Bud deformation	New Zealand
Cecidophyopsis atrichus (Nalepa)	Stellaria graminea L.	Leaf edge rolling, deformation	France, Finland
Epitrimerus silenes-nutantis Roivainen	Silene nutans L.	Vagrant	Finland
Phyllocoptes cazioti (Cotte)	Polycarpon tetraphyllum L.	Flower deformation	France