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Nematode samplings in various areas and crops of Greece were carried out and the recovered nematode species were characterized using morphological and molecular data. Seven species of plant-parasitic nematodes were recovered, three of which are reported for the first time in Greece, including Hemicycliophora poranga, Helicotylenchus dihysteraand Tylenchorhynchus zeae. Four other recovered species had already been reported in Greece, including Bitylenchus hispaniensis, Helicotylenchus microlobus, Nanidorus minorand Scutellonema brachyurus. D2–D3 segments of 28S rRNA gene for all of these nematode species are provided.

During a nematological survey in southern Iran, a population belonging to the family Tylenchidae was recovered from a tomato field in Bushehr province. The recovered population belongs to the genus Filenchus,was described and illustrated herein as F. multistriatusn. sp. It is mainly characterized by having a wide and low annulated lip region continuous with adjacent body; amphidial openings confined to the labial plate; four lines in lateral fields forming three bands, with the two outer bands broken by transverse, and the inner one broken by both transverse and longitudinal lines; and median bulb oval with visible valve and elongate-conoid tail uniformly and gradually narrowing toward the distal region, ending in a widely rounded tip. Its morphological and morphometric differences with three closely similar species were discussed. The phylogenetic relationships of the new species with other relevant genera and species were reconstructed using partial sequences of small, and large subunit ribosomal DNA (SSU and LSU rDNA) sequences. Morphometric and morphological data were also provided for an Iranian population of F. sandnerirecovered from Bushehr province. Both populations were characterised using SEM data.

A new species from the family Tylenchidae was recovered in the grasslands of Isfahan province, Iran, and is herein described based on morphological and molecular data. Ottolenchus isfahanicusn. sp. is mainly characterized by having a faintly annulated cuticle; elongated, slightly sigmoid amphidial apertures developed metacorpus with distinct valve under LM; vulva located at 69.472.3% of body length; large spermatheca about 2.75 times of corresponding body width; and elongated conoid tail with broadly rounded tip. SEM observations showed that the lip region is smooth; the amphidial apertures are elongated, slightly sigmoid slits; and the lateral field is a simple band. It is further characterized by 477-to-515-μm-long females with delicate 5.7-to-6.9-μm-long stylets with small, slightly posteriorly sloping knobs, as well as functional males, in the population. The new species closely resembles O. facultativus, but is separated from it based on morphological and molecular data. It was further morphologically compared with O. discrepans, O. fungivorus, and O. sinipersici. The phylogenetic relationships of the new species with other relevant genera and species were reconstructed using near-full-length sequences of small subunit and D2-D3 expansion segments of large subunit (SSU and LSU D2-D3). In the inferred SSU phylogeny, the newly generated sequence of Ottolenchus isfahanicusn. sp. formed a clade with two sequences of O. sinipersiciand sequences assigned to O. facultativusand O. fungivorus. In the inferred LSU phylogeny, the three newly generated sequences of the new species and LSU sequences of O. sinipersiciand O. discrepansformed a clade.

During a survey in Golestan province, north Iran, two populations belonging to the family Tylenchidae were recovered in association with Quercussp., and a rotten wood sample of an unidentified forest tree. The first recovered species was mainly characterized by having a disc-like differentiation in the frontal end under the light microscope (LM), proposing it as a tentative member of the genus Discotylenchus. Detailed morphological studies using scanning electron microscope (SEM), however, did not reveal a true disc, but showing the smooth cephalic region, and a narrow annulus behind the cephalic plate. Based upon the cephalic region structure, and by lacking a true disc, the species was identified as a member of the genus Filenchus. This population was further characterized by 555 to 618 μm long females, lateral fields with four incisures, 9 to 10 μm long stylet, spermatheca large, including spheroid sperm, post-vulval uterine sac (PUS) 8 to 12 µm long and gradually tapering to an elongate conoid tail with pointed tip. It was compared with relevant species of Filenchushaving four incisures in the lateral fields and similar general morphology. By having a disc-like differentiation in the frontal end under the LM, it was further compared with three similar known species of Discotylenchus. The morphological comparisons with species under two aforementioned genera showed the recovered population belongs to an unknown species, described herein as Filenchus pseudodiscusn. sp. The molecular phylogenetic relationships of the new species using partial small and large subunit ribosomal RNA gene (SSU and LSU D2-D3 rDNA) sequences were reconstructed and discussed. Malenchus gilanensis, the second recovered and studied species was originally established based upon traditional criteria. An updated LSU phylogeny of the genus Malenchusby including M. gilanensiswas also presented and its results were discussed.

Two stunt nematode species, Geocenamus brevidensand Quinisulcius capitatus, were recovered from the potato growing regions of southern Alberta, described and characterized based on integrative taxonomy. Morphometrics, distribution, and host associations of both species are discussed. The Canadian populations of both species displayed minor variations in morphometrical characteristics (viz., slightly longer bodies and tails) from the original descriptions. The populations of G. brevidensand Q. capitatusspecies examined in this study are proposed as standard and reference populations for each respective species until topotype specimens become available and molecularly characterized. Phylogenetic analyses, based on partial 18S, 28S, and ITS sequences, placed both species with related stunt nematode species. The present study updates the taxonomic records of G. brevidensand Q. capitatusfrom a new location, southern Alberta, Canada, and will aid in the decision whether these stunt nematodes should be included in nematode management programs.

The Family Criconematidae is commonly referred as ring nematodes that include some members with economic importance as plant parasites. During a recent nematode inventory survey at Zhejiang Province, China, a new species of genus Nothocriconemoideswas detected in the rhizosphere of elm tree. Nothocriconemoides hangzhouensisn. sp. can be characterized by the female body having annuli with fine longitudinal striations and 2 to 3 anastomoses at the posterior half of the body. The first cephalic annulus is rounded and expanded enclosing the lip region, and the second annulus is narrow, offset, collar like. En faceview shows a central elevated labial disk bearing four distinct equal-sized submedian lobes and “I” shaped oral aperture. Excretory pore is located 3–4 annuli posterior to esophageal bulb. Vagina is straight and vulva closed. The ventral side of postvulval annuli is inverted, in majority of individuals. Anus is indistinct and located on the next annuli posterior to vulva. Tail is short, conoid, with forked or branched terminus. Juveniles are devoid of collar-shaped annuli in the lip region. The cephalic region has two rounded annuli where the first annulus shows slight depression in the middle. Body annuli are finely crenated. Anus is indistinct and located 3 to 4 annuli from tail terminus. Tail is short ending in a single lobed terminus. Phylogenetic studies based on analysis of the D2–D3 expansion segments of the 28 S rRNA, ITS rRNA, partial 18 S rRNA, and coxI gene revealed that the new species formed a separate clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close relationships with Discocriconemella sinensis. Additionally, this is the first record of genus Nothocriconemoidesfrom China.

The tea plant is native to China; the country has the greatest tea production areas in the world. In an attempt to investigate the nematode biodiversity associated with the tea plantations of Hangzhou, Zhejiang Province, a population of stunt nematode was detected. This group of nematodes is comprised of migratory ecto-parasites of roots and can subsist on a variety of host plants. Therefore, the detected population was studied carefully using the integrative taxonomy approach and identified as a new species of genus Geocenamus. Geocenamus chengin. sp. can be characterized by females having six incisures in the lateral field; labial region is dome shaped and slightly offset from the rest of the body having four to five annuli; head framework is weakly developed; deirids are absent; excretory pore is located at the anterior region of basal pharyngeal bulb. Under SEM, the vulva is a transverse slit, vulval lips are elongated and ellipsoidal with epiptygma. The tail is annulated, elongated, and conical having bluntly pointed tip and a terminal hyaline region that forms 21 to 33% of the tail length. Spicule is 22 to 25 μm long, gubernaculum is saucer shaped; bursa is crenated covering the tail until the hyaline tail region. Morphologically, the species is close to G. circellus, G. joctus, G. loofi, G. ordinarius, G. processus, G. tetyllus, and G. tortilis. Phylogenetic relationships of the new species based on D2-D3 expansion domains of 28 S, ITS, and 18 S rRNA genes indicated that G. chengin. sp. clustered in a separate clade with G. vietnamensis.

Cultivated Cretan mountain tea or Malotira (Sideritis syriacaL.) was found to be infected by Meloidogyne haplaand Meloidogyne javanicain the island of Crete. The authors provide the first molecular characterization of M. haplain Greece and the first report of Cretan mountain tea or Malotira as a host of Meloidogynespecies worldwide. In addition, Meloidogyne hispanicawas found infecting aloe (Andros island) and corn (Drama, North Greece) consisting the first reports of natural infection of these plants by M. hispanicain Europe. Furthermore, infection of corn by M. incognitaand soybean by M. javanica(Drama, North Greece) are reported for the first time in Greece. Integrative taxonomical approach based on perineal pattern and EP/st ratio, as well as the region of the mitochondrial genome between the cytochrome oxidase subunit II (coxII) and 16S rRNA mitochondrial DNA (mtDNA) genes was used to differentiate Meloidogynespecies.

Three populations of Xiphinemanon-americanumgroup species were detected in agricultural and natural ecosystems, during routine surveys for plant-parasitic nematodes in Spain. Based on morphological and molecular analyses, the species were identified as Xiphinema histriaeand Xiphinema lapidosum, being this the first record and molecular characterization of both species in Spain. The morphometrics and morphology of the Spanish populations agree with those of the original description and paratype specimens and the present study provided a first description of the second to fourth juvenile stages of both species. A detailed study on the morphology in the Spanish populations of X. histriae, as well as in paratypes, showed a pseudo-Z-organ with weakly muscularized wall and containing numerous small dense granular bodies, which was different to the original description by Lamberti et al. (1993). This new finding suggests that X. histriaemust be considered a member of the morphospecies Group 5 of X.non-americanum. Phylogenetic analysis based on D2 to D3 expansion segments of 28S gene, ITS1 and partial CoxI gene indicated that X. histriaeand X. lapidosumare phylogenetically related with other Xiphinemanon-americanumgroup spp. reported from Spain. Considering the pathological and economic importance of this group of nematodes, the combination of morphological characters, measurements, and molecular analysis is crucial for accurate identification of these species.

Seven needle nematode species of the genus Longidorushave been reported in Ukraine. Nematological surveys for needle nematodes were carried out in Ukraine between 2016 and 2017 and two nematode species of Longidorus(L. caespiticolaand L. poessneckensis) were collected from natural and anthropogenically altered habitats on the territory of Opillia and Zakarpattia in Ukraine. Nematodes were extracted from 500 cm3of soil by modified sieving and decanting method. Extracted specimens were processed to glycerol and mounted on permanent slides and subsequently identified morphologically and molecularly. Nematode DNA was extracted from single individuals and PCR assays were conducted as previously described for D2–D3 expansion segments of 28S rRNA. Sequence alignments for D2–D3 from L. caespiticolashowed 97%–99% similarity to other sequences of L. caespiticoladeposited in GenBank from Belgium, Bulgaria, Czech Republic, Russia, Slovenia, and Scotland. Similarly, D2–D3 sequence alignments from L. poessneckensis, showed 99% to other sequences of L. poessneckensisdeposited in GenBank from Slovakia and Czech Republic. Morphology, morphometry, and molecular data obtained from these samples were consistent with L. caespiticolaand L. poessneckensisidentification. To our knowledge, these are the first reports of L. caespiticolaand L. poessneckensisin Ukraine, extending the geographical distribution of these species.

Nematode samplings in cultivated and wild olive in Crete, Greece, yielded the presence of Bitylenchus hispaniensis, Helicotylenchus microlobus, Helicotylenchus vulgaris, Merlinius brevidens, and Pratylenchoides alkani. With the exception of H. microlobusand M. brevidens, reports of these plant-parasitic nematode species constitute new records for Greece. Bitylenchus hispaniensisis also reported for first time in a country outside of Spain, where it was originally described. Pratylenchoides alkaniis herein reported for the second time in the Mediterranean area and for the first time in association with olive. Two further populations of H. microlobusand H. vulgaris, from walnut and goji berry from Greece, were identified. Molecular data for all of these nematode species are provided, resulting in the first integrative identification of these Greek populations.

Longidorids are economically important plant-parasitic nematodes because several species are virus vectors. Populations of Paralongidorus saliand Longidorus jonesi, isolated from woody perennials of Hangzhou, Zhejiang, China, were characterized molecularly and morphologically. The morphometric data of the Chinese populations of both species were compared with other populations. The present study provided a first record of the occurrence of Paralongidorusin China coupled with description of the first-stage Juvenile and male of L. jonesi. Phylogenetic analysis based on 18S and D2–D3 expansion segments of 28S gene indicated that L. jonesiclustered with L. jonesireported from Japan and P. saligrouped with P. bikanerensisfrom Iran. Considering the pathological and economic importance of this group of nematodes, the study emphasized the need of updated descriptions from accurately identified specimens, isolation of sufficient material for examination, and molecular and phylogenetic analysis for a better understanding and diagnostics of Longidorid nematodes.

Plant-parasitic nematodes such as Longidorus euonymusand Helicotylenchus multicintctusare species widely distributed in central Europe as well as in Mediterranean area. In Greece, both species have been previously reported but no morphometrics or molecular data were available for these species. Nematode surveys in the rhizosphere of grapevines in Athens carried out in 2016 and 2017, yielded a Longidorusspecies identified as Longidorus euonymus. Similarly, a population of Helicotylenchus multicinctuswas detected infecting banana roots from an outdoor crop in Tertsa, Crete. For both species, morphometrics and molecular data of Greek populations were provided, resulting in the first integrative identification of both nematode species based on morphometric and molecular markers, confirming the occurrence of these two nematodes in Greece as had been stated in earlier reports.

Longidorid nematodes comprise more than 500 species, and Longidorusand Xiphinemaare the most diversified, prevalent, and cosmopolitan genera within plant-parasitic nematodes. The genus Longidoruscomprise a group of species, some of which are vectors of plant viruses. New sampling for needle nematodes was carried out in a grapevine area in Thessaloniki, northern Greece, and one nematode species of Longidorus(L. leptocephalus) was recovered. Nematodes were extracted from soil samples by modified sieving and a decanting method. Extracted specimens were processed using glycerol, mounted on permanent slides, and subsequently identified morphologically. Nematode DNA was extracted from individual, live specimens, and PCR (Polymerase Chain Reaction) assays were performed for D2-D3 expansion segments of 28S rRNA, ITS1 rRNA, and partial mitochondrial COIregions. Morphology and morphometric data obtained from this population were consistent with the original description and reported populations of L. leptocephalus. To our knowledge, this is the first report of L. leptocephalusin Greece and the second in the Mediterranean Basin after the record of the species from Slovenia, extending the geographical distribution of this species in Europe.

During a recent inventory survey of the nematofauna of tea plantation at Zhejiang Province, China, Discocriconemella parasinensisn. sp. was detected in the rhizosphere of Camellia sinensis. The new species can be characterized by having the uninterrupted rounded labial disc, en faceview showing rectangular-rounded labial plate without submedian lobes, R = 82.6 (80–86), Rex = 22 (21–23), stylet length of 68.3 (59–76) μm, excretory pore located 1–2 annuli posterior to the esophageal bulb, vulva open, postvulval body elongated conoid, and tail conoid with bilobed terminus. Morphologically, the species shares the same lip-type with D. discolabia, D. mauritiensis, D. mineira, D. perseae, and D. sinensis. Phylogenetic relationships of the new species based on D2–D3 expansion segments of 28S, ITS, and 18S rRNA genes revealed that D. parasinensisn. sp. formed a separated clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close phylogenetic relationships with Criconemoides geraerti.

A population of a species of dagger nematode (Xiphinema) belonging to the non-americanumgroup was recovered from the fields of kola nut (Colasp.) in southern Nigeria. The morphological and morphometric data obtained from this population were consistent with the characteristics of the species Xiphinema ifacolum. In addition, molecular identification based on D2-D3 expansion segments of 28S rRNA and partial mitochondrial COIgene regions confirmed its identity. According to our knowledge, this is the first report of the species from Nigeria, and the second report from Africa, after the original description from Foulaya, Guinea.

Spiral nematode species of the genus Rotylenchushave been reported on olive (Olea europaeaL.) in several Mediterranean countries (Castillo et al., 2010; Ali et al., 2014). Nematological surveys for plant-parasitic nematodes on olive trees were carried out in Tunisia between 2013 and 2014, and two nematode species of Rotylenchuswere collected from the rhizosphere of olive cv. Chemlali in several localities of Tunisia (Tables 1,2). Twenty-two soil samples of 3 to 4 kg were collected with a shovel from the upper 50 cm of soil from arbitrarily chosen olive trees. Nematodes were extracted from 500 cm3of soil by centrifugal flotation method (Coolen, 1979). Specimens were heat killed by adding hot 4% formaldehyde solution and processed to pure glycerin using the De Grisse’s (1969) method. Measurements were done using a drawing tube attached to a zeiss III compound microscope. Nematode DNA was extracted from single individuals and PCR assays were conducted as described by Castillo et al. (2003). Moderate-to-low soil populations of these spiral nematodes were detected (5.5–11.5, 1.5–5.0 individuals/500 cm3of soil, respectively). This prompted us to undertake a detailed morphological and molecular comparative study with previous reported data. Morphological and molecular analyses of females identified these species as Rotylenchus eximiusSiddiqi, 1964, and Rotylenchus incultusSher, 1965. The morphology of R. eximiusfemales (five specimens studied) was characterized by having a hemispherical lip region clearly off set, with four to five annuli, body without longitudinal striations, lateral fields areolated in the pharyngeal region only, stylet 32 to 36 μm long, and broadly rounded tail. The morphology of R. incultusfemales (51 females and 16 males; Table 2) was characterized by a hemispherical lip region with the basal annulus subdivided by irregular longitudinal striations, with three, rarely four annuli; stylet 21.5 to 27.5 μm long, female tail hemispherical with terminus regularly annulated; phasmids anterior to anus level (3–6 annuli above). The morphology of the isolated nematodes agreed with previous descriptions of R. eximius(Siddiqi, 1964; Castillo and Vovlas, 2005) and R. incultus(Sher, 1965; Castillo and Vovlas, 2005; Vovlas et al., 2008), respectively. A single individual was used for DNA extraction. Primers and PCR conditions used in this research were specified in Cantalapiedra-Navarrete et al. (2013), and a single amplicon of 800, 1,100, and 450 bp was obtained and sequenced for D2 to D3, ITS1, and cytochrome c oxidase subunit 1 (coxI), respectively. Sequence alignments for D2 to D3 (KX669231–KX669233), ITS1 (KX669238–KX669240), and coxI(KX669244–KX669245) from R. eximius, showed 99% to 97%, 98% to 94%, 93% similarity to other sequences of R. eximiusdeposited in GenBank (EU280794–DQ328741, EU373663–EU373664, JX015401–JX015402, respectively). Similarly, D2 to D3 (KX669234–KX669237), ITS1 (KX669241–KX669243), and coxI(KX669246–KX669249) sequence alignments from R. incultus, showed 99%, 99% to 95%, 99% to 90% similarity, respectively, to other sequences of R. incultusdeposited in GenBank (EU280797, EU373672–EU373673, JX015403, respectively). The best fitted model of DNA evolution was obtained using jModelTest v. 2.1.7 (Darriba et al. 2012) with the Akaike information criterion. BI analyses were performed under the general time reversible (GTR) with invariable sites and a gamma-shaped distribution of substitution rates (GTR + I + G) model for ITS1 and coxI. Phylogenetic analyses of ITS1 and coxIusing Bayesian inference (BI) placed R. eximiusand R. incultusfrom Tunisia in subclades that included all R. eximiusand R. incultussequences deposited in GenBank (Fig. 1), which agrees with previous results (Cantalapiedra-Navarrete et al., 2013). Morphology, morphometry, and molecular and phylogenetic data obtained from these samples were consistent with R. eximiusand R. incultusidentification. To our knowledge, this is the first report of R incultusin Tunisia. Consequently, all these data suggest that spiral nematode species of the genus Rotylenchusare predominant in olive as previously reported in other Mediterranean areas (Ali et al., 2014).

Plant-parasitic nematode species have been reported on several occasions from coastal sand dunes, including Longidorusand Rotylenchusspecies (Vovlas et al., 2008; De Luca et al., 2009; Mateille et al., 2014). In April 2016, 10 soil samples of3 to 4 kg from the rhizosphere of Tamarix smyrnensiswith different vegetation around (viz. Elymus farctus, Lycium schweinfurthii, Crithmum maritimum, and Arthrocnemumsp.) were collected for diagnosis of plant-parasitic nematodes. The area of sampling was a coastal sand dune near the archeological site of Komos, southwest of Crete, Greece. Low soil populations of a needle and a spiral nematode were detected (3 and 8 individuals/1,000 cm3of soil, respectively), which prompted us to undertake a detailed morphological and molecular comparative study with previous reported data. Nematodes were extracted from soil with the wet sieving and decanting method (Cobb, 1918). Morphological and molecular analyses of females identified these species as Longidorus kuiperiBrinkman, Loof and Barbez, 1987, and Rotylenchus eximiusSiddiqi, 1964. The morphology of L. kuiperifemales (six specimens studied) was characterized by having a slender body; very broad lip region (27 6 1.5 [25 to 30] μm in width); short, hemispherical tail; body length of (7.1 6 0.8 [6.5 to 8.5] mm); vulva position at 47% to 55% of body length; odontostyle length of (105 6 6.5 [90 to 115] μm); males very common (but less frequent than females [45% vs55%]); tail region with 15 to 20 supplements and bulged terminal cuticle. The morphology of R. eximiusfemales (four specimens studied) was characterized by having a hemispherical lip region clearly set off; with four annuli; body without longitudinal striations; lateral fields areolated in the pharyngeal region only; stylet 36 to 38 μm; and broadly rounded tail. The morphology of the isolated nematodes agreed with previous descriptions of L. kuiperi(Brinkman et al., 1987; De Luca et al., 2009), and R. eximius(Siddiqi, 1964; Castillo and Vovlas, 2005). A single individual was used for DNA extraction. Primers and polymerase chain reaction conditions used in this research were specified in Cantalapiedra et al. (2013) and Archidona-Yuste et al. (2016), and a single amplicon of 800 and 1,100 bp was obtained and sequenced, respectively. D2-D3 (KX398055-KX398056) and ITS sequence alignments (751 and 648 bp, respectively) from L. kuiperi(KX398057) showed 98% to 99% similarity, differing in 4, and from 6 to 12 nucleotides, respectively, to other sequences of L. kuiperideposited in GenBank from Italy and Spain (AM911623, AM905267-AM905270, respectively),with a query coverage of 99%. Similarly, D2-D3 sequence alignment from R. eximius(KX398058) showed 100% to 99% to another sequence of R. eximiusdeposited in GenBank from Italy and Spain (EU280794, DQ328741), differing in zero to three nucleotides, respectively, and a query coverage of 81%. Phylogenetic analyses using Bayesian Inference placed L. kuiperiin a highly supported (100%) clade that included all L. kuiperisequences deposited in GenBank (Archidona-Yuste et al., 2016), and R. eximiusin a highly supported (100%) clade that included all R. eximiussequences deposited in GenBank (Cantalapiedra-Navarrete et al., 2013). All identification methods were consistent with L. kuiperiand R. eximius. To our knowledge, this is the first report of L. kuiperiand R. eximiusin Greece. Consequently, all these data suggest that coastal sand dunes in Europe constitute environmental conditions optimal for colonization and development of L. kuiperi, as previously reported (De Luca et al., 2009). Similarly, R. eximiushas been reported in several Mediterranean countries, including Italy, Morocco, Spain, and Tunisia (Castillo and Vovlas, 2005), and this report extend the geographical distribution of this species.