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Phytoplasmas (‘Candidatus Phytoplasma) are uncultivable, wall-less bacteria classified as members of the class Mollicutes. They affect numerous plant species causing devastating yield losses in diverse crops worldwide. They have specific lifestyle as obligate symbionts of plants and insects, and need both hosts for dispersal in nature. In Europe, the most significant aetiological agents of grapevine yellows (GY) diseases are bois noir phytoplasma (BNp: ‘Ca. P. solani’ ; 16SrXII-A subgroup) and flavescence dorée phytoplasma (FDp: 16SrV group). Although symptoms are similar, epidemiology of those two phytoplasmas differs since they are transmitted by different insect-vectors. While FDp is transmitted exclusively by monophagous vector Scaphoideus titanus Ball., BNp is transmitted by several polyphagous vectors with Hyalesthes obsoletus Sign. being the main one. Moreover, FDp is classified as a quarantine pathogen in Europe and represents a great threat to viticulture. The aim of this study was to compare variability of GY phytoplasmas and their epidemiological characteristics of pathosystems in Croatian and Serbian vineyards. Study encompassed samples of grapevine, insect-vectors and reservoir plants as integrative component of pathosystems. The sampling was performed in late summer and autumn of 2019 – 2021 on locations in selected Croatian and Serbian viticulture regions. Total nucleic acids were extracted followed by detection and identification of phytoplasma by PCR/RFLP analyses of 16S rDNA and triplex real-time PCR. Multilocus sequence typing (MLST) was performed in order to analyze isolates in more detail by amplification, sequencing and phylogenetic analysis of stamp and vmp genes (BNp) and map and sec genes (FDp).The results have confirmed the presence of BNp and FDp in grapevine samples from both countries, as well as in insect vectors S. titanus and H. obsoletus and reservoir host plants such as Urtica dioica L. and Ailanthus altissima Mill. MLST analysis has revealed significant variability and presence of different genotypes among BNp and FDp strains from Croatia and Serbia, with Croatian strains being more variable. Stamp gene proved to be the most indicative molecular marker for differentiation among strains. Even though Croatia and Serbia are neighbouring countries with the similar viticultural practices, our results have shown that GY pathosystems differ regarding phytoplasma genotypes that were prevalent in sampled vineyards.

Fitoplazme (rod 'Candidatus Phytoplasma')su fitopatogene bakterije bez stanične stijenke, srodne mikoplazmama – patogenima ljudi i životinja. Predstavljaju obligatne unutarstanične parazite domaćinima različitih carstava: Animalia i Planta. Dok u biljkama izazivaju brojne bolesti, u kukcima parazitiraju uglavnom bez štetnih posljedica. Kukci-domaćini iz porodica Cicadellidae i Cixiidae (cikade, cvrčci) ili Psyllidae (lisne buhe) predstavljaju i glavne vektore fitoplazmi neophodne za njihov opstanak i širenje u prirodi. Rutinski uzgoj fitoplazmi u čistoj kulturi in vitro još uvijek nije moguć, zbog čega se u istraživanjima primarno koriste metode molekularne biologije: PCR-RFLP, PCR u stvarnom vremenu i multigenska tipizacija (multilocus sequence typing ; MLST). MLST obuhvaća ekvenciranje i filogenetske analize house-keeping-gena odgovarajućeg stupnja varijabilnosti i gena membranskih proteina, koji sudjeluju u interakciji fitoplazmi s domaćinom, što ih čini bitnim za istraživanja molekularne epidemiologije. Bolesti uzrokovane fitoplazmama su zabilježene na brojnim poljoprivrednim kulturama, na kojima uzrokuju smanjenje prinosa i ekonomski značajne gubitke. Zlatna žutica vinove loze je bolest epidemijskog karaktera, uzrokovana fitoplazmom Flavescence dorée (FD) i predstavlja ozbiljan problem u vinogradima Hrvatske i Srbije. Fitoplazma FD je karantenski patogen, što podrazumijeva posebne mjere kontrole širenja i sprečavanja prisustva ovog patogena i njegovog kukca vektora. Glavni vektor bolesti je ampelofagna cikada sjevernoameričkog porijekla Scaphoideus titanus, koja fitoplazmu prenosi na vinovu lozu u zatvorenom epidemiološkom ciklusu. Također, prirodni autohtoni vektor na Balkanu i u sjevernoj Italiji je i cikada Dictyophara europaea koja fitoplazmu preuzima iz asimptomatskog domaćina Clematis vitalba (pavitina). Cilj istraživanja je usporedba varijabilnosti i raznolikosti fitoplazme FD i njenih epidemioloških karakteristika u patosistemima vinograda Hrvatske i Srbije, uključujući istraživanja karakteristika kukaca-vektora i biljaka-rezervoara patogena kao integralnih komponenti patosistema. Dodatna prednost je otkrivanje novih vektora i novih biljaka-rezervoara fitoplazme FD s dugoročnim ciljem pronalaženja mogućnosti kontrole epidemijskog širenja ovog patogena u obje države.

A new vagrant eriophyoid mite species of the archaic genus Pentasetacus (Schliesske 1985), P. novozelandicus n. sp., is described with the aid of conventional microscopy, confocal laser scanning microscopy and scanning electron microscopy. It was found on Araucaria heterophylla, which is an araucarian that is endemic to Norfolk Island and introduced to New Zealand. Partial sequences of mitochondrial barcode COI gene and D1–D2 domains of nuclear rDNA of two pentasetacid mites, P. araucariae (MK903025 and MK898944) and P. novozelandicus n. sp. (MK903024 and MK898943) are provided. Molecular phylogenetic analyses of full-length D1–D2 eriophyoid sequences, including GenBank sequences and newly generated sequences of pentasetacids, confirmed the monophyly of Pentasetacidae but failed to resolve the basal phylogeny of Eriophyoidea. This may be because the D1–D2 domains of 28S are hypervariable in Eriophyoidea. Moreover, in pentasetacids D1–D2 sequences are about 20% shorter than in other eriophyoids, and thus harder to align. Two types of anal lobes are described in Eriophyoidea: (1) Eriophyidae s.l. and Phytoptidae s.l. have bilaterally symmetric lobes; (2) pentasetacids have non-divided lobes. The presence of an anal secretory apparatus, comprising internal structures that have previously been described in Eriophyidae s.l. and Phytoptidae s.l., is confirmed in pentasetacid genera. The phylogeny of pentasetacids is also discussed in the context of the paleobiography of Araucariaceae.

Supplementary morphological descriptions of five Cecidophyopsis species collected in Europe (Serbia, Austria, Italy and Montenegro) are given: Cecidophyopsis vermiformis from Corylus avellana L. (Betulaceae), C. hendersoni from Yucca gigantea Lem. (Asparagaceae), C. verilicis from Ilex aquifolium L. (Aquifoliaceae), C. psilaspis from Taxus baccata L. (Taxaceae) and C. malpighianus from Laurus nobilis L. (Lauraceae). Males of C. vermiformis, C. verilicis, C. hendersoni and C. malpighianus, and immatures of C. hendersoni and C. verilicis, are described for the first time. C. verilicis is recorded for the first time in the fauna of Serbia and the European region. Female cuticle-lined internal genitalia of five Cecidophyopsis species are studied under confocal laser scanning microscopy. A several steps of oviposition in cecidophyines is proposed based on CLSM observations on their internal genitalia. Sequences of the barcoding region of the mitochondrial cytochrome oxidase subunit I (mtCOI) gene are given for the following species: C. hendersoni, C. verilicis, C. psilaspis and C. malpighianus.

A new vagrant eriophyoid mite species, Setoptus tsugivagus n. sp. Chetverikov (Eriophyoidea, Phytoptidae, Nalepellinae, Nalepellini), is described from the needles of the western hemlock, Tsuga heterophylla (Rafinesque) Sargent (Pinaceae) in Vancouver, Canada. The new species can be distinguished from all other members of Setoptus by a distinct pattern of several short longitudinal ridges on the posterior half of the prodorsal shield. Elements of the anal secretory apparatus (ASA) were observed in adults of S. tsugivagus n. sp., suggesting that the ASA is present in both major phylogenetic lineages of Eriophyoidea (Eriophyidae s. l. and Phytoptidae s. l.). Therefore, this structure could be a synapomorphy for all Eriophyoidea. We briefly discuss the function and morphological variety of the ASA in Eriophyoidea. D2 28S rDNA sequences of four nalepelline species were obtained: Boczekella reticulata Bagnyuk 1987 (GenBank accession number MK124605), Nalepella tsugifoliae Keifer 1953 (MK124606), Setoptus pini Boczek, 1964 (MK124607), and S. tsugivagus n. sp. (MK124608). Molecular phylogenetic analyses of D2 28S rDNA sequences of the mites of the subfamily Nalepellinae confirmed monophyly of the tribe Nalepellini and retrieved Setoptus and Nalepella as polyphyletic. Additionally, our data indicate that 28S rDNA sequence KF782472.1, previously reported to be Trisetacus ehmanni Keifer 1963 by Li et al. (2014), belongs to another species of the genus Trisetacus, possibly T. quadrisetus (Thomas), and the sequence KF782471.1, previously reported to be Trisetacus sp., might belong to T. juniperinus (Nalepa). We also discuss the systematics of nalepellines and their host association with conifers.

Tribe Anthocoptini Amrine & Stasny, 1994 Aculus Keifer, 1959, Occ. Paps. 1:5 Type species: Aculus ligustri (Keifer, 1938):190–191, 159 (Fig. XVI) Revised diagnosis. BODY gENERALLY SPINDLE fORM, SOMEWHAT DORSOVENTRALLY fLATTENED AS A RULE. GNATHOSOMA RELATIVELY SMALL, PROjECTINg DIAgONALLY DOWNWARDS: CHELICERAE SHORT, NEARLY STRAIgHT; ORAL STYLET SHORT, RECURVINg WELL bELOW CHELICERAE bASE. PRODORSAL SHIELD SUbTRIANgULAR, WITH A bROAD AND ROUNDED APICALLY, SOMETIMES SHALLOW, ANTERIOR LObE EXTENDINg OVER bASE Of gNATHOSOMA ALMOST COVERINg SETAE ep; PROTOgYNES Of SOME SPECIES WITH ONE OR TWO PAIRS Of fORWARD-DIRECTED SMALL SPINES fROM ANTERIOR POINT Of LObE, OR fROM UNDERSIDE. SCAPULAR TUbERCLES ON REAR SHIELD MARgIN WELL-SPACED, PROjECTINg bACKWARDS AND OUTWARDS. COXAE WITH THREE PAIRS Of SETIfEROUS TUbERCLES. LEgS WITH USUAL SERIES Of SETAE. OPISTHOSOMA Of PROTOgYNES USUALLY WITH DORSAL ANNULI bROADER AND STRONgLY DIffERENTIATED fROM VENTRAL ANNULI; OfTEN A SLIgHT SUbDORSAL fURROW EXTENDINg A SHORT DISTANCE CAUDAD fROM REAR SHIELD MARgIN. IN SOME SPECIES, DIffERENTIATION Of DORSAL AND VENTRAL OPISTHOSOMAL ANNULI IS LESS EXPRESSED. ALL OPISTHOSOMAL SETAE (c2, d, e AND f) PRESENT. A SHORT MID-DORSAL RIDgE MAY bE PRESENT AT POSTERIOR END Of OPISTHOSOMA IN SOME SPECIES. FEMALE gENITAL COVERfLAP USUALLY WITH fURROWS; INTERNAL TRANSVERSAL APODEMA Of NORMAL LENgTH, bROAD. DEUTOgYNES LACKINg ANTERIOR LObE SPINES, WITH DORSAL AND VENTRAL ANNULI LESS DIffERENTIATED AND MICROTUbERCLES MORE OR LESS SUPPRESSED. Distribution and hosts. AT LEAST 260 Aculus SPECIES HAVE bEEN DESCRIbED fROM AROUND THE WORLD bASED ON AMRINE et al. (2003) AND A REVIEW Of THE MOST RECENT LITERATURE. Remarks. THE DIAgNOSIS Of THIS gENUS IS fOUNDED ON THE ORIgINAL DESCRIPTION bY KEIfER (1959) AND ObSERVATIONS Of AUTHORS fOR THE PAPER PUbLISHED HERE. THIS REVISED DIAgNOSIS IS ALSO ESTAbLISHED ON THE NEW SPECIES DESCRIPTION bELOW.

Aculus crassulae sp. nov. Knihinicki & Petanović FIgS. 1–4 Description. FEMALE (N=11). FIgS. 1–2. BODY 246 (196–251) [IDIOSOMA 234 (185–230)], WIDTH 79 (63–78), SPINDLEfORM IN SHAPE, ORANgE TO PINK IN COLOUR. Gnathosoma 21 (17–22), DOWNCURVED, DORSAL PEDIPALP gENUAL SETAE (d) 6 (4–7), PEDIPALP COXAL SETAE (ep) 6 (4–6), CHELICERAL STYLETS 22 (19–23). Prodorsal shield SUbTRIANgULAR 38 (37– 43), 70 (55–72) WIDE, WITH bROAD fRONTAL LObE, ROUNDED APICALLY, SHALLOW, bUT EXTENDINg OVER bASE Of gNATHOSOMA, ALMOST COVERINg SETAE ep. TUbERCLES Of SETAE (sc) ON REAR SHIELD MARgIN, WELL-SPACED, 27 (25–30) APART, PRODORSAL SETAE (sc) 14 (13–17), PROjECTINg bACKWARDS AND OUTWARDS. PRODORSAL SHIELD ORNAMENTATION WITHOUT LINES, bUT WITH NUMEROUS SMALL NODULES COVERINg WHOLE SURfACE AND LATERAL SIDES, OCCURRINg IN SHORT, LINEAR SEgMENTS (AS VISIbLE IN SEM IMAgE, FIg. 2A). Legs WITH ALL USUAL SETAE PRESENT. Leg I 41 (33–39; MEASURED fROM bASE Of TROCHANTER); fEMUR 9 (9–10), bASIVENTRAL fEMORAL SETA (bv) 14 (5–14); gENU 5 (5–6), ANTAXIAL gENUAL SETA (l ″) 31 (28–37); TIbIA 10 (9–10), PARAXIAL TIbIAL SETA (l ′) 6 (5–7); TARSUS 7.5 (7–8), PARAXIAL fASTIgIAL TARSAL SETA (ft ′) 17 (12–19), ANATAXIAL fASTIgIAL TARSAL SETA (ft ′ ′) 26 (20–26), VENTROMESAL SETA (u ′) 5 (4–6), TARSAL SOLENIDION (ω) 8 (7–8), DISTALLY ROUNDED WITH SMALL, DISTINCTIVE KNOb, TARSAL EMPODIUM (em) 6 (6–7), 4- RAYED WITH SECONDARY bRANCHES. Leg II 35 (30–36); fEMUR 8 (8– 10), bASIVENTRAL fEMORAL SETA (bv) 15 (13–15); gENU 5 (5–6), ANTAXIAL gENUAL SETA (l ″) 6 (4–7); TIbIA 9 (7–9); TARSUS 8 (7–8), PARAXIAL fASTIgIAL TARSAL SETA (ft ′) 7 (5–6), ANATAXIAL fASTIgIAL TARSAL SETA (ft ′ ′) 20 (18–22), VENTROMESAL SETA (u ′) 5 (4.5–5), TARSAL SOLENIDION (ω) 7.5 (7–8), DISTALLY ROUNDED WITH SMALL, DISTINCTIVE KNOb, TARSAL EMPODIUM (em) 6.5 (6– 6), 4- RAYED WITH SECONDARY bRANCHES. Coxigenital region WITH 9 (7–10) COXIgENITAL ANNULI. COXAE SPARSELY gRANULATED WITH SHORT DASHES, PROSTERNAL APODEME 12 (10–12), DISTINCT, fORKED ANTERIORLY. PROXIMAL SETAE ON COXISTERNUM I (1b) 7 (7–11), TUbERCLES 14 (12–14) APART; PROXIMAL SETAE ON COXISTERNUM II (1a) 14 (14–18), TUbERCLES 10 (9–10) APART; PROXIMAL SETAE ON COXISTERNUM III (2a) 33(15[bROKEN]–36), TUbERCLES 25 (22–28) APART. Opisthosoma WITH LATERAL DIffERENTIATION bETWEEN LARgER DORSAL ANNULI AND MORE NUMEROUS VENTRAL ANNULI, WITH SHORT, SHALLOW, MID-DORSAL RIDgE ON LAST 10–12 DORSAL ANNULI fROM REAR, 58 (53–59) DORSAL ANNULI, SMOOTH; 63 (55–63) VENTRAL ANNULI, WITH ELLIPTICAL MICROTUbERCLES. LATERAL SETA (c2) 38 64(51–64, N=6) APART ON ANNULUS 5 (4–6) fROM gENITALIA; VENTRAL SETA I (d) 55 (30–54) LONg ON ANNULUS 18 (16–19), TUbERCLES 45 (32–41) APART; VENTRAL SETA II (e) 15 (11–21), ON ANNULUS 35(34–37), TUbERCLES 25 (17–22) APART; VENTRAL SETA III (f) 23 (15–25) ON 5TH (5TH–6TH) ANNULUS fROM REAR, TUbERCLES 22 (22–24) APART. CAUDAL SETAE (h2) 45 (22–57). ACCESSORY SETA (h1) AbSENT. External genitalia 15 (13–15), 24 (22–25) WIDE, gENITAL COVERfLAP gRANULATED ANTERIORLY, WITH 12 (10–13) SHORT, MOSTLY ObLIqUE AND SOME LONgITUDINAL STRIATIONS IN A SINgLE ROW; PROXIMAL SETAE ON COXISTERNUM III (3a) 14 (10–20); TUbERCLES 18 (14–19) APART. Internal genitalia WITH ANTERIOR, TRANSVERSAL APODEME TRAPEZOIDAL, LONgITUDINAL bRIDgE RELATIVELY LONg, SPERMATHECAL TUbES DIRECTED LATERO-POSTERAD, SPERMATHECAE Egg-SHAPED, gLObOSE. MALE (N=2). FIg 1. MALE SHORTER THAN fEMALE, gENERALLY SIMILAR. BODY 181–191, 54–57 WIDE. Gnathosoma 15–16, d 5–6, ep 3, CHELICERAE 17–19; DOWN-CURVED. Prodorsal shield 34–37, 51–55 WIDE WITH bROAD fRONTAL LObE, ROUNDED APICALLY, SHALLOW, DESIgN RESEMbLINg fEMALE, sc 11–14, TUbERCLES 22–23 APART. Legs WITH ALL USUAL SETAE. Leg I 32, fEMUR 9–10, bv 7–9; gENU 5, l ″ 21–22; TIbIA 7, l ′ 4; TARSUS 6, ft ″ 16–20, ft ′ 12–14, u ′ 4–5, ω 6, DISTALLY ROUNDED WITH SMALL, DISTINCTIVE KNOb, em 6, 4-RAYED WITH SECONDARY bRANCHES. Leg II 30; fEMUR 8–9, bv 10–11; gENU 5, l ″ 5–6; TIbIA 6–7; TARSUS 7, ft ″ 14–15, ft ′ 6–7, u ′ 4–5, ω 6–7; em 6, 4- RAYED WITH SECONDARY bRANCHES. Coxigenital region AS SHOWN WITH 9 MICROTUbERCULATED ANNULI, 1b 6–8, TUbERCLES 11 APART; 1a 11–14, TUbERCLES 8 APART; 2a 19–20, TUbERCLES 21–24 APART. COXAE I AND II SPARSELY gRANULATED AS IN fEMALE, PROSTERNAL APODEME 8, DISTINCT, fORKED ANTERIORLY. Opisthosoma SIMILAR TO fEMALE, WITH AbOUT 52–54 DORSAL ANNULI AND 52–54 VENTRAL ANNULI, WITH SHORT, SHALLOW, MID-DORSAL RIDgE ON LAST 10 TO 12 DORSAL ANNULI fROM REAR; c 2 15–22, ON ANNULUS 4–5 (fROM gENITALIA); d 29–31 ON ANNULUS 16–17, TUbERCLES 29–31 APART; e 12 ON ANNULUS 31, TUbERCLES 17 APART; f 21–22 ON 5TH ANNULUS fROM REAR, TUbERCLES 18–20 APART; h2 37–39, h1 AbSENT. External genitalia 17–18 WIDE, EPIANDRUM TYPICALLY ORNAMENTED WITH SMALL gRANULES, 3a 11–12 AND TUbERCLES 12–13 APART. NYMPH (N=1). FIg 3. IN COMPARISON TO ADULTS, IMMATURES LACK THE fRONTAL LObE Of THE PRODORSAL SHIELD AND HAVE SUbEqUAL NUMbERS Of VENTRAL AND DORSAL OPISTHOSOMAL ANNULI (IMMATURE ANNULI NOT DORSO-VENTRALLY DIffERENTIATED). BODY 145, 50 WIDE; VERMIfORM IN SHAPE, TRANSLUCENT TO WHITISH IN COLOUR. Gnathosoma 14, d 4, ep 3, CHELICERAE 17.5. Prodorsal shield 33, 49 WIDE; SEMI-OVOID, ANTERIOR LObE LACKINg, ORNAMENTATION fAINT bUT RESEMbLINg ADULT WITH SIMILAR ARRANgEMENT Of NODULES, sc 6, TUbERCLES 19 APART. Legs. Leg I 25; fEMUR 6, bv 3; gENU 3, l ″ 7; TIbIA 5, l ′ 3; TARSUS 4, ft ″ 12, ft ′ 7, u ′ 4, ω 6, SIMILAR TO ADULT, em 5, 4 -RAYED. Leg II 20; fEMUR 6, bv 6; gENU 3, l ″ 5; TIbIA 4; TARSUS 5, ft ″ 11, ft ′ 4, u ′ 3, ω 5, SIMILAR TO ADULT, em 4.5, 4-RAYED. Coxigenital region WITH 1 b 4, TUbERCLES 10 APART; 1a 6, TUbERCLES 6 APART; 2a 10, TUbERCLES 20 APART. COXAE SPARSELY gRANULATED. PROSTERNAL APODEME AbSENT. COXIgENITAL REgION WITH 8 MICROTUbERCULATED ANNULI. 3a 4, TUbERCLES 7 APART. Opisthosoma. APPEARANCE Of ANNULI SUbEqUAL, NOT DIffERENTIATED AS IN ADULT; MICROTUbERCLES EVENLY PRESENT ON DORSAL ANNULI, SMALLER AND SPARSER ON VENTRAL ANNULI, EVENLY SPACED. WITH 51 DORSAL ANNULI AND 47 VENTRAL ANNULI. c2 20, ON ANNULUS 8 (fROM gENITAL TUbERCLES), 39 APART; d 12 ON ANNULUS 17, TUbERCLES 26 APART; e 12 ON ANNULUS 27, TUbERCLES 13 APART; f 14 ON 5TH ANNULUS fROM REAR, TUbERCLES 17 APART. h 2 10, 9 APART; h1 AbSENT. LARVA (N=1). FIg. 4. BODY 107, 52 WIDE; VERMIfORM IN SHAPE, TRANSLUCENT TO WHITISH IN COLOUR. Gnathosoma 17, d 4, CHELICERAE 14. Prodorsal shield 30, 44 WIDE; SEMI-OVOID, ANTERIOR LObE LACKINg, ORNAMENTATION fAINT bUT RESEMbLINg ADULT WITH SIMILAR ARRANgEMENT Of NODULES, sc 11, TUbERCLES 20 APART. Legs. Leg I 22; fEMUR 7, bv 12; gENU 4, l ″ 19; TIbIA 6, l ′ 6; TARSUS 5, ft ″ 14, ft ′ 9, ω 5, SIMILAR TO ADULT, em 4, 4 -RAYED. Leg II 21; fEMUR 6, bv 9; gENU 4, l ″ 21; TIbIA 4; TARSUS 4, ft ″ 13, ft ′ 9, u ′ 3, ω 6, SIMILAR TO ADULT, em 3, 4-RAYED. Coxigenital region WITH 1 b 8, TUbERCLES 9 APART; 1a 12, TUbERCLES 7 APART; 2a 17, TUbERCLES 15 APART. COXAE SPARSELY gRANULATED. PROSTERNAL APODEME AbSENT. SETAE 3a 7, TUbERCLES 9 APART. Opisthosoma. APPEARANCE Of ANNULI SUbEqUAL, NOT DIffERENTIATED AS IN ADULT; MICROTUbERCLES EVENLY PRESENT ON DORSAL ANNULI, SMALLER AND SPARSER ON VENTRAL ANNULI, EVENLY SPACED. WITH 42 DORSAL ANNULI AND 31 VENTRAL ANNULI. c2 17, ON ANNULUS 2 (fROM gENITAL TUbERCLES), 40 APART; d 28 ON ANNULUS 10, TUbERCLES 24 APART; e 11 ON ANNULUS 20, TUbERCLES 15 APART; f 16 ON 5TH ANNULUS fROM REAR, TUbERCLES 18 APART. h 2 29, 10 APART; h1 AbSENT. DEUTOGYNE FEMALE. NOT ObSERVED. Host plant. Crassula helmsii (KIRK) COCKAYNE: CRASSULACEAE. A PLANT SPECIES CONSIDERED NATIVE TO AUSTRALIA AND NEW ZEALAND. Relationship with the host plant and field observations. CAUSINg DISTORTION AND fORMATION Of “bIg bUD” gALLS WHEREbY LEAVES fAIL TO OPEN AND EXPAND NORMALLY (FIg. 5). LEAVES DEVELOP A DEEP MAgENTA COLOUR COMPARED TO HEALTHY gREEN SHOOTS. THE LEAVES CURL INWARDS TO fORM A gALL-LIKE STRUCTURE. UPON REACHINg MATURITY, THE MITES WERE ObSERVED OUTSIDE THE gALL IN READINESS fOR DISPERSAL. ONLY THE TERRESTRIAL OR EMERgENT gROWTH fORMS Of C. helmsii WERE fOUND TO bE INfESTED bY A. crassulae sp. nov. AND IT WAS NOT ObSERVED IN THE SUbMERgED PLANT fORM. ADDITIONAL RESEARCH (S. VARIA et al. UNPUbLISHED DATA 2017) SUggESTS THAT THE OPTIMAL TEMPERATURE fOR MITE DEVELOPMENT IS AbOVE 20 o C. Type material. Holotype fEMALE (SINgLE SPECIMEN ON MICROSCOPE SLIDE PREPARATION) EX INSIDE bUD Of AUSTRALIAN SWAMP STONECROP, Crassula helmsii, LAKE COLAC, VICTORIA, S 38°19′43.07 " E 143°35′43.04″, COLL. R. ADAIR, 20.IV.2013 (DEPOSITED IN ASCT). Paratypes ON 5 MICROSCOPE SLIDE PREPARATIONS (SOME SLIDES HAVE MULTIPLE SPECIMENS) WITH SAME COLLECTION DATA AS HOLOTYPE; EX C. helmsii, CAUSINg bUD gALLS, IN qUARANTINE fACILITY, CABI, COLONY DERIVED fROM LAKE COLAC, VICTORIA AS IN HOLOTYPE, COLL. S. VARIA, 2013. OTHER SPECIMENS ALSO EXAMINED. Etymology. THE SPECIES NAME crassulae IS A fEMININE NOUN IN gENITIVE AND REfLECTS THE NAME Of THE PLANT gENUS ON WHICH THE NEW SPECIES WAS fOUND. Differential diagnosis and remarks. THE NEW SPECIES, A. crassulae, IS CHARACTERIZED bY THE fRONTAL LObE WHICH IS bROAD AND ROUNDED APICALLY, SHALLOW, bUT EXTENDINg OVER THE bASE Of THE gNATHOSOMA ALMOST COVERINg SETAE ep. THERE IS LATERAL DIffERENTIATION bETWEEN THE LARgER DORSAL ANNULI AND MORE NARROW AND NUMEROUS VENTRAL ANNULI. UNLIKE MOST OR ALL OTHER SPECIES IN THE gENUS Aculus, A. crassulae sp. nov. HAS A SHORT MID-DORSAL RIDgE AT THE END Of THE OPISTHOSOMA. WE COMPARED Aculus crassulae sp. nov. WITH THE ONLY OTHER Aculus SPECIES DESCRIbED fROM THE PLANT fAMILY CRASSULACEAE, I.E. Aculus cotyledonis (KEIfER, 1939). THESE TWO SPECIES ARE SIMILAR IN THE NUMbER Of DORSAL ANNULI AND LENgTH Of THE sc SETAE. HOWEVER, THERE ARE SEVERAL MAjOR MORPHOLOgICAL DIffERENCES. THE NEW SPECIES CAN bE DISTINgUISHED bY HAVINg AN OPULENCE Of DISTINCTIVE NODULES COVERINg THE ENTIRE PRODORSAL SHIELD WHICH ARE PRESENT IN A SERIES Of SHORT, LINEAR SEgMENTS. IN CONTRAST, THE PRODORSAL SHIELD Of A. cotyledonis IS COMPRISED Of A STRONg NETWORK Of LINES AND IT HAS MUCH LONgER DORSAL SETAE. ADDITIONALLY, THE SPECIES DIffER fROM EACH OTHER IN THE NUMbER Of RAYS ON THE EMPODIA (4-RAYED IN A. crassulae sp. nov. AND 5-RAYED IN A. cotyledonis). ALSO, UNLIKE OTHER CURRENTLY KNOWN SPECIES Of Aculus, THE DORSAL ANNULI IN THE NEW SPECIES fORM A CHARACTERISTIC, SHORT, SHALLOW, MID-DORSAL RIDgE AT THE POSTERIOR. THE DAMAgE SYMPTOMS ATTRIbUTED TO bOTH SPECIES ALSO DIffER. Aculus cotyledonis IS fOUND AT THE VERY bASE Of THE ROSETTE Of LEAfLETS Of THE HOST PLANT, D. caespitosa. IT bROWNS AND WRINKLES THE LEAf SURfACES, AND CAUSES AN UNEVEN WHITE SURfACE PULVERULENCE, WHILE THE NEW SPECIES CAUSES THE DISTORTION AND fORMATION Of “bIg bUD” gALLS ON C. helmsii WHEREbY LEAVES fAIL TO OPEN AND EXPAND NORMALLY. Aculus crassulae sp. nov. IS ALSO SIMILAR TO Aculus haloragi (LAMb, 1953) WHICH WAS fIRST DESCRIbED fROM NEW ZEALAND bY LAMb (1953) WITHIN THE gENUS Thamnacus. LATER, MANSON (1984) REDESCRIbED THE SPECIES AND REASSIgNED IT TO THE gENUS Aculops, CHANgINg THE NAME INTO haloragis. AMRINE AND STASNY (1994), AS WELL AS XUE AND ZHANg (2008), TREATED THIS SPECIES AS A MEMbER Of THE gENUS Aculus, PRObAbLY bECAUSE Of THE SHAPE Of THE SUbDORSAL SHIELD, AND RETURNED THE ORIgINAL SPECIES NAME Aculus haloragi. IT WAS LISTED AS CAUSINg DEfORMED INfLORESCENCES, LEAf AND bUD gALLS ON A RANgE Of Haloragis SPP. (HALORAgACEAE). Aculus crassulae sp. nov. AND A. haloragi INHAbIT PLANTS THAT bELONg TO THE SAME PLANT ORDER, SAXIfRAgALES. HENCE, IT WAS IMPORTANT TO COMPARE THEM fURTHER. THE ORIgINAL DESCRIPTIONS Of THE TWO SPECIES HAVE bEEN STUDIED AND A SUMMARY Of MEASUREMENTS ARE PRESENTED IN TAbLE 1. THE MAIN SIMILARITIES bETWEEN THE NEW SPECIES AND A. haloragi fROM NEW ZEALAND INCLUDE THE PRODORSAL SHIELD DESIgN AND ALSO THE fACT THAT IT HAS THE SAME NUMbER Of EMPODIAL RAYS. SOME SETAL LENgTHS ARE ALSO COMPARAbLE. HOWEVER, THERE ARE SOME MAjOR DIffERENCES SUCH AS A. crassulae sp. nov. HAVINg A MUCH LONgER bODY LENgTH AND A gREATER NUMbER Of DORSAL AND VENTRAL ANNULI THAN A. haloragi, AS WELL AS THE PRESENCE Of A SHORT MID- DORSAL RIDgE AT THE POSTERIOR END Of THE OPISTHOSOMA. IN THE ORIgINAL DESCRIPTION Of A. haloragi, LAMb (1953) MENTIONED THE PRESENCE Of A SHALLOW fURROW ON EITHER SIDE Of THE OPISTHOSOMA EXTENDINg TO THE CAUDA. HOWEVER, WHEN MANSON (1984) REDESCRIbED THAT SPECIES AfTER RE-EXAMININg LAMb’S TYPE MATERIAL, HE DID NOT ACCEPT LAMb’S ObSERVATION AND THIS IS PRObAbLY THE REASON WHY HE REMOVED IT fROM THE gENUS Thamnacus. NEITHER AUTHOR DESCRIbED OR ILLUSTRATED A SHORT, SHALLOW MID-DORSAL RIDgE EXTENDINg TOWARDS THE POSTERIOR Of THE OPISTHOSOMA. IN THE NEW SPECIES, A. crassulae, THIS CHARACTER IS EVIDENT IN SLIDE-MOUNTED SPECIMENS AND CAN CLEARLY bE SEEN IN THE SEM (SEE FIg. 2A). ......continued on the next page DNA barcoding. THE SEqUENCINg RESULTED IN A 606 bP LONg fRAgMENT Of THE MTCOI bARCODE REgION (SENSU HEbERT et al. 2004). BASE PAIR fREqUENCIES SHOWED THAT THE REgION IS AT-RICH (A: 0.210, C: 0.135, G: 0.162, T: 0.493). PAIRWISE COMPARISON Of OVERLAPPINg MTCOI fRAgMENTS USED IN THIS STUDY INDICATED A HIgH LEVEL Of gENETIC DIVERgENCE bETWEEN THE ANALYZED POPULATION Of A. crassulae sp. nov. AND TWO CONgENERIC SPECIES A. amygdali AND A. ichnocarpi (22.6% AND 23.1%, RESPECTIVELY). THE DIVERgENCE RATES ARE IN CONgRUENCE WITH INTERSPECIfIC VARIATIONS IN OTHER MITE TAXONOMIC gROUPS (STEVENS & HOgg 2006; LEWANDOWSKI et al. 2014; SKORACKA & DAbERT 2010; MARTIN et al. 2010; SKORACKA et al. 2013; CHETVERIKOV et al. 2012 & 2015; VIDOVIĆ et al. 2015; CVRKOVIĆ et al. 2016).

A new species of eriophyoid mite Aceria alhagi n. sp. inhabiting the weed Alhagi maurorum Medik., is described from the type locality in Iran, but it was also collected from Uzbekistan, Turkey and Armenia. This mite causes changes of the leaves and inflorescence. Infested plants develop cauliflower-like galls on the inflorescence and leaves deforming the reproductive structures and inhibiting seed production. The potential reduction in seed set suggests that this mite could constitute a potential biological control agent against this noxious weed. To investigate intraspecific variability between A. alhagi n. sp. populations from Iran, Turkey and Armenia, we analysed molecular sequences of the mitochondrial cytochrome oxidase subunit I (mtCOI). These results indicated that there are no significant intraspecific divergences among populations of A.alhagi n. sp. from the five different localities in three West Asia countries. This finding can be used in the future research of certain mite populations as biological control agent. © Vidović B. et al.

The European lantern fly, Dictyophara europaea, is an alternative vector of the Flavescence doree phytoplasma (FDp) disease of grapevine in European vineyards, enabling infection initiation from wild reservoir compartment (Clematis vitalba). Heretofore recorded rate of D. europaea FDp-infection has been very low (3%), making it less epidemiologically significant than would be expected based on reservoir plant infection rate (30%). In this study we present findings on a heavily FDp-infected D. europaea population ( gt 60%), on the natural Wolbachia infection of populations with low FDp-infection rates (DeWo+) and on Wolbachia absence in highly FDp-infected population (DeWo-). We examine several possible causes underlying the differences in vector infection rates: (a) population genetic characteristics of D. europaea and correlation with Wolbachia strain wEur natural infections, (b) Wolbachia effects on fitness components of DeWo+ laboratory colony and (c) rate of reservoir plant FDp-infection and differences in FDp genotypes harboured by low and highly infected vector populations. The vector genetic diversity level was found to be lower in DeWo+ than in uninfected individuals and to exhibit a different evolution of fixed haplotypes. All DeWo+ populations were infected with the same strain of wEur. The FDp was found to be genetically diversified (five genotypes) but had no relation to infection rates. We did not find evidence of fitness upgrades with regard to Wolbachia infection status. Although more experimentation is needed, it seems that Wolbachia confers protection against FDp or is in competition with FDp according to the observed correlations: low FDp-infected vector populations are infected with Wolbachia and vice versa.