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Tylenchorhynchus clarus Allen, 1955 (Figure 5, Table 4), Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2022, Analyses of morphological and molecular characteristics of Telotylenchinae from Iran point at the validity of the genera Bitylenchus and Sauertylenchus, pp. 425-446 in Zootaxa 5169 (5) on page 435, DOI: 10.11646/zootaxa.5169.5.2, http://zenodo.org/record/6952625, {"references":["Allen, M. W. (1955) A review of the nematode genus Tylenchorhynchus. University of California Publications in Zoology, 61, 129 - 165."]}

Bitylenchus parvus (Allen, 1955) Jairajpuri, 1982 Syn: Tylenchorhynchus parvus Allen, 1955 Bitylenchus parvus (Allen, 1955) Siddiqi, 1986 (Figure 2, Table 3) Description Female Body straight to curved ventrally after heat fixation. Cuticle annuli 0.9–1 μm wide at mid-body. Lateral field consisting of four longitudinal incisures, often areolated. Lip region continuous to slightly offset, 7–7.7 μm wide at base, 4.0–4.1 μm high, and bearing six or seven transverse annuli. Cephalic framework slightly sclerotized, outer margins extending two or three body annuli posteriorly. Stylet strong, basal knobs laterally directed; the conus almost half of the total stylet length. Dorsal pharyngeal gland orifice located 2.2–2.3 μm behind stylet knobs. Median pharyngeal bulb oval, 10–11 μm wide; basal bulb pyriform. Hemizonid 2–4 annuli anterior to secretoryexcretory pore. Reproductive system didelphic, amphidelphic; spermatheca rounded, with globular sperm. Vagina 12–13 μm long, almost 50–60% of the vulval body width. Intestinal fasciculi present in the intestine and inside the post rectal sac which extends into almost the entire tail cavity. Tail cylindrical, finely striated or sometimes smooth terminus, bearing 60–67 annuli on ventral side. Hyaline region of tail terminus 5–6 μm thick. Phasmids located 25–30 μm posterior to anus, located in the posterior half of the tail. Male Not found. REMARKS Compared to the original description of B. parvus Allen (1955), the Iranian population has a lower c' ratio (11.5–12.1 vs 13–16). No other difference in morphological or morphometric diagnostic characters was found. Although this population shows similarity to Sauertylenchus maximus, it can be distinguished from it by a smaller body and stylet (680–800 vs 940–1062, and 17.7–19.6 vs 20–24 μm), and the number of tail annuli (60–67 vs 25– 45). This species was recovered from the rhizosphere of alfalfa (Medicago sativa) in Zanjan and Qazvin provinces during the present study., Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2022, Analyses of morphological and molecular characteristics of Telotylenchinae from Iran point at the validity of the genera Bitylenchus and Sauertylenchus, pp. 425-446 in Zootaxa 5169 (5) on pages 430-432, DOI: 10.11646/zootaxa.5169.5.2, http://zenodo.org/record/6952625, {"references":["Allen, M. W. (1955) A review of the nematode genus Tylenchorhynchus. University of California Publications in Zoology, 61, 129 - 165.","Jairajpuri, M. S. (1982) Some studies on Tylenchorhynchinae: The subgenus Bitylenchus Filipjev, 1934, with description of Tylenchorhynchus (Bitylenchus) depressus n. sp. and a key to species of Bitylenchus. Mededelingen van de Fakulteit Landbouwwetenschappen Rijksuniversiteit Gent, 47, 765 - 770.","Siddiqi, M. R. (1986) Tylenchida Parasites of Plants and Insects. Commonwealth Institute of Parasitology, Slough, UK, 645 pp."]}

Sauertylenchus maximus (Allen, 1955) Siddiqi, 2000 Syn: Bitylenchus maximus (Allen, 1955) Siddiqi, 1986 Tylenchorhynchus maximus Allen, 1950 Tylenchorhynchus wilskii Kornobis, 1980 (Brzeski, 1998) Bitylenchus wilskii (Kornobis, 1980) Jairajpuri, 1982 Bitylenchus wilskii (Kornobis, 1980) Siddiqi, 1986 (Figure 4, Table 3) Description Female Body curved ventrally to C-shaped after heat fixation. Cuticle with distinct annuli, 1.5–2.3 μm wide at midbody. Lateral field with four longitudinal incisures, outer bands areolated. Lip region offset, hemispherical, 8.0– 9.0 μm wide at base, 4.0–5.0 μm high, and bearing six or seven distinct transverse annuli. Cephalic framework lightly sclerotized, outer margins extending over two or three body annuli. Stylet moderately strong, knobs rounded, slightly directed posteriorly; the conus almost half of the total stylet length. Dorsal pharyngeal gland orifice located 2.0–2.1 μm behind stylet knobs. Median pharyngeal bulb oval, 12–13 μm wide; basal bulb pyriform, abutting anterior intestine. Reproductive system didelphic, amphidelphic, spermatheca elongated, empty. Vagina 10 μm long, 40–60% of the vulval body diameter. Intestinal fasciculi present throughout intestine and inside post rectal sac which enters into about two-thirds of the tail length. Tail cylindrical with a hemispherical, annulated terminus, bearing 33–40 annuli on ventral side. Hyaline portion thickness 6–7 μm. Phasmids located 16–17 μm posterior to anus, in the anterior half of the tail. Male Not found. Remarks Compared to the original description of S. maximus by Allen (1955), the Iranian populations differ by the absence of males. The Iranian populations of S. maximus were recovered from Semnan, Ardabil and West Azerbaijan provinces in the rhizosphere of peach (Prunus persica), grass, hawthorn (Crataegus aronia) and apple (Malus pumila), respectively., Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2022, Analyses of morphological and molecular characteristics of Telotylenchinae from Iran point at the validity of the genera Bitylenchus and Sauertylenchus, pp. 425-446 in Zootaxa 5169 (5) on pages 434-435, DOI: 10.11646/zootaxa.5169.5.2, http://zenodo.org/record/6952625, {"references":["Allen, M. W. (1955) A review of the nematode genus Tylenchorhynchus. University of California Publications in Zoology, 61, 129 - 165.","Siddiqi, M. R. (2000) Tylenchida Parasites of Plants and Insects. 2 nd edition. CABI Publishing, Wallingford, Oxon, UK, 833 p. https: // doi. org / 10.1079 / 9780851992020.0000","Siddiqi, M. R. (1986) Tylenchida Parasites of Plants and Insects. Commonwealth Institute of Parasitology, Slough, UK, 645 pp.","Brzeski, M. W & Dolinski C. M. (1998) Compendium of the genus Tylenchorhynchus Cob, 1913 sensu lato (Nematodea: Belonolaimidae). Russian Journal of Nematology, 6 (2), 189 - 199.","Jairajpuri, M. S. (1982) Some studies on Tylenchorhynchinae: The subgenus Bitylenchus Filipjev, 1934, with description of Tylenchorhynchus (Bitylenchus) depressus n. sp. and a key to species of Bitylenchus. Mededelingen van de Fakulteit Landbouwwetenschappen Rijksuniversiteit Gent, 47, 765 - 770."]}

Bitylenchus dubius (Bütschli, 1873) Filipjev, 1934 Syn: Tylenchus dubius Bütschli, 1873 Anguillulina dubia (Bütschli, 1873) Goody, 1932 Tylenchus (Bitylenchus) dubius (Bütschli, 1873) Filipjev, 1934 Tylenchorhynchus dubius (Bütschli, 1873) Filipjev, 1936 Bitylenchus dubius (Bütschli, 1873) Siddiqi, 1986 (Figure 1, Table 3), Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2022, Analyses of morphological and molecular characteristics of Telotylenchinae from Iran point at the validity of the genera Bitylenchus and Sauertylenchus, pp. 425-446 in Zootaxa 5169 (5) on page 428, DOI: 10.11646/zootaxa.5169.5.2, http://zenodo.org/record/6952625, {"references":["Butschli, O. (1873) Beitrage zur Kenntnis der freilebenden Nematoden. Nova acta Academiae Caesareae Leopoldino-Carolinae Germanicae Naturae Curiosorum, 36, 1 - 124.","Filipjev, I. N. (1934) Harmful and Useful Nematodes in Rural Economy. Moscow, Leningrad, USSR, 440 pp. [In Russian]","Filipjev, I. N. (1936) On the classification of the Tylenchinae. Proceedings of the Helminthological Society of Washington, 3, 80 - 82.","Siddiqi, M. R. (1986) Tylenchida Parasites of Plants and Insects. Commonwealth Institute of Parasitology, Slough, UK, 645 pp."]}

Tylenchorhynchus microconus Siddiqi, Mukherjee and Dasgupta, 1982 (Figurs 6, Table 4), Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2022, Analyses of morphological and molecular characteristics of Telotylenchinae from Iran point at the validity of the genera Bitylenchus and Sauertylenchus, pp. 425-446 in Zootaxa 5169 (5) on page 439, DOI: 10.11646/zootaxa.5169.5.2, http://zenodo.org/record/6952625, {"references":["Siddiqi, M. R., Mukherjee, B. & Dasgupta, M. K. (1982) Tylenchorhynchus microconus n. sp., T. crassicaudatus leviterminalis n. subsp. and T. coffeae Siddiqi and Basir, 1959 (Nematoda: Tylenchida). Systematic Parasitology, 4, 257 - 262. https: // doi. org / 10.1007 / BF 00009626"]}

Bitylenchus serranus Gomez-Barcina, Siddiqi & Castillo, 1992 (Figure 3, Table 3), Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2022, Analyses of morphological and molecular characteristics of Telotylenchinae from Iran point at the validity of the genera Bitylenchus and Sauertylenchus, pp. 425-446 in Zootaxa 5169 (5) on page 433, DOI: 10.11646/zootaxa.5169.5.2, http://zenodo.org/record/6952625, {"references":["Gomez-Barcina, A., Siddiqi, M. R. & Castillo, P. (1992) The genus Bitylenchus Filipjev, 1934 (Nematoda: Tylenchida) with descriptions of two new species from Spain. Journal of the Helminthological Society of Washington, 59, 96 - 110."]}

Trophurus ussuriensis Eroshenko, 1981 (Figure 7, Table 4), Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2022, Analyses of morphological and molecular characteristics of Telotylenchinae from Iran point at the validity of the genera Bitylenchus and Sauertylenchus, pp. 425-446 in Zootaxa 5169 (5) on page 440, DOI: 10.11646/zootaxa.5169.5.2, http://zenodo.org/record/6952625, {"references":["Eroshenko, A. S. (1981) Plant parasitic nematodes of underwood; families Tylenchorhynchidae and Hoplolaimidae (Nematoda). In: Svobodnozhivuschie I fitopatogennye nematody fauny Dal'nego Vostoka Biol. Pedolog. Inst. of Far Eastern Research Center of USSR Academic Science Vladivostok, pp. 22 - 27 + 85 - 92."]}

Additional file 1: Figure S1 - BlobTools-based interrogation of genome assembly of Gr-Line 19 to verify for single-taxon origin of the original sequences. Panel A: Each Gr-Line19 scaffold is represented by a single filled circle. Each scaffold is positioned in the main panel based on its GC proportion (x-axis) and coverage by reads from PacBio sequences (y-axis). On the top right the colours of the individual blobs are linked to their taxonomic origin. At the bottom of the main Blobtool figure, the size of the circles is linked to scaffold size. Panel B: on the left the % of unmapped versus mapped Gr-Line19 PacBio reads are presented, and the right the taxonomic origin of the reads. Figure S2 - BlobTools-based interrogation of genome assembly of Gr-Line 22 to verify for single-taxon origin of the original sequences. Panel A: Each Gr-Line22 scaffold is represented by a single filled circle. Each scaffold is positioned in the main panel based on its GC proportion (x-axis) and coverage by reads from PacBio sequences (y-axis). On the top right the colours of the individual blobs are linked to their taxonomic origin. At the bottom of the main Blobtool figure, the size of the circles is linked to scaffold size. Panel B: on the left the % of unmapped versus mapped Gr-Line22 PacBio reads are presented, and the right the taxonomic origin of the reads. Figure S3 - Multiple sequence alignment of Gr-CLE-1 protein sequences to verify the conservation of the CLE domain in putative CLE-1 genes. Each gene is represented by a gene identifier. Two genes are included for Gr-Line19 (Gros19_g2219.t1 and Gros19_g2223.t1) and two for Gr-Line22 (Gros22_g4869.t1 and Gros22_g4874.t1). The CLE1 sequence identified in Heterodera glycines (Q9BN21) is included as an outgroup.

Description of Pratylenchoides persicus n. sp. (Figures 1 & 4; Tables 1 & 2) Female. Body slightly curved ventrally after heat fixation. Cuticle with distinct annuli, 1.5–1.8 µm wide at midbody; lateral field with six longitudinal incisures at deirid and mid-body, and four incisures at post-phasmid, the outer bands areolated at posterior part of pharynx, 7.0–8.8 µm wide and occupying 31–38 % of the body width at mid-body. Lip region off-set by slight depression with body contour, rounded anteriorly or slightly flattened and bearing four or five distinct but fine annuli, 9.4–10.3 µm wide at base and 3.6–4.1 µm high (Fig. 1 B–D and 4 A & B). Stylet strong with rounded or posteriorly flattened basal knobs; the conus 9.0–11.2 µm long or half of the total stylet length. Dorsal pharyngeal gland orifice located 3–4 µm behind the stylet knobs. Median bulb oval, 13–19 µm long and 10.0–12.3 µm wide with refractive valves. Deirids at the level of hemizonid or slightly anterior to it. Secretory-excretory pore located in anterior half of the pharyngeal glands or 110–126 µm from the body anterior end; hemizonid 2–4 annuli anterior to secretory-excretory pore. Pharyngeal glands abutting or slightly overlapping intestine dorsally; all three nuclei of dorsal and subventral glands located anterior to the pharyngo-intestinal valve (Fig. 1 C–D and 4 F–H). Intestinal fasciculi visible in some specimens. Reproductive system didelphic, amphidelphic; spermatheca rounded, filled with globular sperm. Vagina 9–12 µm long and 40–50 % of the body width at vulva. Tail cylindrical, with truncate to low rounded and coarsely annulated terminus. Hyaline thickness 7–10 µm. Phasmids located 21–30 µm posterior to anus, in the posterior half of the tail (Fig. 1 J–L and 4 L–N). Male. Similar to female in general view. Body slightly curved ventrally. Lateral field with six incisures; outer band areolated. Lip region high, rounded or slightly flattened. Stylet slightly more slender than that of females (Fig. 1 E & F and 4 C & D). Spicules curved ventrally, gubernaculum simple. Tail conical, tapering gradually to a conoid or more or less subcylindrical terminus (Fig. 1 M–N and 4 O). Diagnosis and relationships. Pratylenchoides persicus n. sp. is characterized by a lip region rounded anteriorly or slight flattened and bearing four or five fine annuli, pharyngeal glands abutting or slightly overlapping intestine dorsally, all the three gland nuclei located anterior to the pharyngo-intestinal valve and tail cylindrical with truncate to low rounded terminus. This species comes closest to P. heathi Baldwin, Luc & Bell, 1983; P. sheri Robbins, 1985; P. arenicola Ryss & Sturhan, 2001; P. laticauda Braun & Loof, 1967 and P. erzurumensis Yüksel, 1977. In comparison with the original description of P. heathi (Baldwin et al. 1983), the new species can be separated by shorter body length (601–784 vs 820–1330 µm), smaller stylet (19.7–22 vs 23.5–27.5 µm), shorter tail (35–46 vs 44–69 µm) and different shape of tail terminus (truncate to low rounded vs rounded) in females, as well as a smaller stylet (19.8–20.9 vs 23.5–27 µm) in males. P. persicus n. sp. has a shorter body than P. sheri (601–784 vs 898–1173 µm), a shorter stylet (19.7–22 vs 22–25.5 µm), a shorter pharynx (154–194 vs 190–217 µm), and a shorter tail (35–46 vs 47–64 µm) in females. Furthermore, P. persicus n. sp. males have a shorter stylet (19.8–20.9 vs 21.5–24 µm) and spicules (21.7–27 vs 28–31 µm). P. persicus n. sp. differs from P. arenicola in the shape of tail terminus in males (usually conical vs cylindrical), as well as a shorter stylet (19.7–22 vs 25 µm in females and 19.8–20.9 vs 23–25 µm in males), also in body length (601–784 vs 980–1100 µm in females and 623–665 vs 800– 890 µm in males). The other two related species, P. laticauda and P. erzurumensis, have a longer overlap of the pharyngeal glands with the intestine (vs abutting or very short overlapping), posterior position of the subventral gland nuclei to the cardium (at least one of the subventral gland nuclei close to the cardium vs all the three nuclei distinctly anterior to the cardium), different glands shape (saccate vs elongate-cylindrical) and a smaller number of head annuli (usually 3 wide annuli vs 4 or 5 fine annuli). Furthermore, males of P. erzurumensis have a conoid lip region which is different from that of females (rounded or flattened, similar to that of females, in P. persicus n. sp.). Type material. Holotype female (slide number KA1100), eight paratype females and three males and five juveniles on slide numbers KA1101-KA1105 kept in the nematode collection of Department of Plant Protection, College of Agriculture, University of Zanjan, Iran; two female paratypes, two males and one juvenile on slide numbers WT3668 and WT 3669 in the Nematode Collection of Plantenziektenkundige Dienst, Wageningen, The Netherlands. Type habitat and locality. The specimens were collected by the second author (Ali Eskandari) from the rhizosphere of oregano (Origanum vulgare L.) in Abr forest, Shahrud county, Semnan province, northern Iran (GPS coordinates: N 37° 45' 385"– E 55° 02' 287"), May 2014. Etymology. The species epithet refers to the Latin name of Iran, the country where it was recovered and identified., Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2016, Morphological and molecular characterization of Pratylenchoides persicus n. sp. (Nematoda: Merliniidae) and additional data on two other species of the genus from Iran, pp. 459-474 in Zootaxa 4205 (5) on page 461, DOI: 10.11646/zootaxa.4205.5.4, http://zenodo.org/record/198032, {"references":["Baldwin, G., Luc, M. & Bell, A. H. (1983) Contribution to the study of the genus Pratylenchoides Winslow (Nematoda: Tylenchida). Revue de Nematologie, 6, 111 - 125.","Robbins, R. T. (1985) Description of Pratylenchoides sheri n. sp. (Nematoda: Pratylenchidae). Journal of Nematology, 17, 107 - 111.","Ryss, A. Y. & Sturhan, D. (2001) Three new species of the genus Pratylenchoides from Germany (Tylenchida: Pratylenchidae). Zoosystematica Rossica, 10, 15 - 31."]}

Iranian population of Pratylenchoides cf. nevadensis Talavera & Tobar, 1996 (Figures: 3 & 6; Table 4) Female. Body slightly curved ventrally to C-shaped after heat fixation. Cuticular annuli 1.3–1.7 µm wide at midbody. Lateral field with four or six longitudinal incisures at mid-body, with always four at the deirid and in the post-phasmid portion of the body; occupying 34–41 % of the body width at mid-body. Lip region off-set by slight depression with the body contour, rounded anteriorly or slightly flattened and bearing three-four distinct annuli, 8.8–11.0 µm wide at base and 3.2–4.0 µm high (Fig. 3 C–E and 6 A & B). Stylet with rounded knobs. Dorsal pharyngeal gland orifice located 2–3 µm behind stylet knobs. Deirids at the level of hemizonid or slightly anterior to it. Secretory-excretory pore located 88–125 µm from the body anterior end; hemizonid 2–3 annuli anterior to the pore. Pharyngeal glands overlapping intestine dorsally for 30–56 µm, or about 1.5–2.0 times body width. The nuclei of the dorsal and subventral glands mostly located posterior to the pharyngo-intestinal valve, in some specimens the dorsal gland is anterior to or level with the valve. All gland nuclei hardly seen and glands cover about only half of the body width (Fig. 3 D & E and 6 F–H). Spermatheca rounded, filled with round sperm. Tail cylindrical to subcylindrical, ending to a coarsely striated terminus. Phasmids 19–29 µm posterior to the anus (Fig. 3: L–O and 6: K–M). Male. Similar to females in general view. Body slightly curved ventrally. Lateral field with four or six incisures; outer band areolated. Lip region conical and higher than that of females (Fig. 3 F & H and 6 C & D). Tail gradually tapering, ending to a conical terminus (Fig. 3 J & K and 6 N). Remark. Compared to the original description of P. nevadensis (Talavera & Tobar, 1996), the Iranian population has a slightly shorter stylet (18.8–21.8 vs 22–26 µm) and shorter pharynx (145–183 vs 178–254 µm). No other difference in morphologic or morphometric diagnostic characters was found. Our population also has affinities with P. ritteri and P. alkani, but differs in having narrow pharyngeal glands which do not fill the whole body cavity and in having different positions of the pharyngeal gland nuclei. During the present study, this population was recovered from the rhizosphere of walnut trees (Juglans regia) in Rashakan region, Urmia county, West Azerbaijan province, northwestern Iran (GPS coordinates: N 37° 19' 2" – E 45° 17'48")., Published as part of Azizi, Kourosh, Eskandari, Ali, Karegar, Akbar, Ghaderi, Reza, Elsen, Sven Van Den, Holterman, Martijn & Helder, Johannes, 2016, Morphological and molecular characterization of Pratylenchoides persicus n. sp. (Nematoda: Merliniidae) and additional data on two other species of the genus from Iran, pp. 459-474 in Zootaxa 4205 (5) on pages 466-471, DOI: 10.11646/zootaxa.4205.5.4, http://zenodo.org/record/198032, {"references":["Talavera, M. & Tobar, A. (1996) Description of Pratylenchoides nevadensis sp. n. from southern Spain (Tylenchida: Pratylenchidae). Afro-Asian Journal of Nematology, 6, 46 - 49."]}

Iranian population of Pratylenchoides laticauda Braun & Loof, 1966 (Figures: 2 & 5; Table 3) Female. Body slightly curved ventrally to C-shaped after heat fixation. Cuticle with distinct annuli, 1.3–1.6 µm wide at mid-body. Lateral field with six longitudinal incisures, occupying 29–37 % of the body width at mid-body; the number of incisures reduce to four in the post-phasmid level. Lip region off-set by slight depression with the body contour, rounded anteriorly or slightly flattened and bearing three or four distinct annuli, 9.9–11.0 µm wide at base and 3.2–4.4 µm high. Stylet strong with rounded to slightly posteriorly directed knobs, the conus 9.6–11.5 µm long and slightly longer than the shaft (Fig. 2 C–E and 5 A & B). Dorsal pharyngeal gland orifice located 2–4 µm behind stylet knobs. Deirids at the level of hemizonid or slightly anterior to it. Secretory-excretory pore 103–127 µm from the body anterior end; hemizonid 2–3 annuli anterior to the pore. Pharyngeal glands overlapping intestine dorsally, about 9–27 µm, the nucleus of the dorsal and one of the subventral glands located anterior to the pharyngo-intestinal valve and the nucleus of the other subventral gland with variable position relative to the oesophago-intestinal valve (level or slightly anterior or posterior to the valve) (Fig. 2 D & E and 5 F–I). Spermatheca rounded, filled with round sperm. Tail cylindrical, with rounded and coarsely striated terminus. Phasmids 16–30 µm posterior to the anus (Fig. 2 H–I and 5 O–R). Male. Similar to females in general view. Body slightly curved ventral to C-shape. Lateral field with six incisures, oblique striae and areolation may be observed. Lip region rounded, higher and narrower than that of female. Stylet slightly more slender than that of female (Fig. 2 F & G and 5 C & D). Spicules and gubernaculum typical of the genus. Tail conical, tapering gradually to a conoid or somewhat subcylindrical terminus (Fig. 2 L & M and 5 S). Remarks. Compared to the Dutch population of P. laticauda (Braun & Loof 1966), the Iranian population has a slightly shorter stylet (19.2–22.8 vs 22–23 µm). During the present study, this species was recovered from the rhizosphere of apricot trees (Prunus armeniaca) in Ilvang region, Khalkhal county, Ardebil province, northwestern Iran (GPS coordinates: N 37° 42' 17" – E 48°27'44") as a new record for Iranian nematofauna.