Raski (1956) described a nematode species as
The genus
Current taxonomic views on the systematics of the genera included in the family Tylenchulidae have been reviewed recently (Mokaram Hesar et al., 2019); the authors concluded that the genera
The present study provides morphological and molecular support on the synonymy of
The populations of
Species and populations of
Species | Locality | Associated plant | GenBank accession No. |
---|---|---|---|
|
Boldaji, Chaharmahal and Bakhtiari | Alfalfa ( |
MN088372 |
|
Dehdasht, Kohgiloyeh and Boyer-Ahmad | Alfalfa ( |
– |
|
Sureshjan, Chahrmahal and Bakhtiari | Rough bluegrass ( |
– |
|
Behbahan, Khuzestan | Gundelia ( |
MN088373 |
|
Andimeshk, Khuzestan | Howthorn ( |
– |
|
Dezful, Khuzestan | Jujube ( |
– |
|
Dezful, Khuzestan | Ziziphus ( |
MN088374 |
|
Andimeshk, Khuzestan | Howthorn ( |
MN088375 |
|
Dehdez, Khuzestan | Mount Atlas mastic or Baneh ( |
MN088376 |
|
Basht, Kohgiloyeh and Boyer-Ahmad | Unknown citrus | – |
|
Baghmalek, Khuzestan | Weeping willow ( |
MK733978 |
|
Dehdasht, Kohgiloyeh and Boyer-Ahmad | Unknown grasses in a canebrake | MK733979 |
For molecular analysis, a single female nematode of each of the populations was transferred into a drop of distilled water on a microscopic slide and examined under the light microscope. Each specimen was washed three times in deionized water and then transferred into an Eppendorf tube with 25 µl distilled water. Posteriorly, 25 µl lysis buffer (23.75 µl NaCl 0.2 M and Tris-HCL 0.2 M, 1.0 µl β-mercaptoethanol and 0.25 µl proteinase K) was added to each Eppendorf tube. Nematode specimen was crushed with a microhomogeniser for 2 min. The tubes were incubated at 65°C (1 hr) and then at 95°C (15 min) (Tanha Maafi et al., 2003).
DNA amplification was carried out based on the protocols described by Tanha Maafi et al. (2003). The D2–D3 expansion regions of the 28 S rRNA gene were amplified with the forward D2A (5′
The PCR products were purified using the QIAquick Gel Extraction Kit (Takapozist, Iran) according to the manufacturer’s instruction and used for direct sequencing. The PCR products were sequenced in both directions at BioNeer Inc. (Korea).
The obtained sequences (Table 1) were compared with sequences of other taxa in GenBank with a BlastN homology search and then the closest sequences were selected for phylogenetic analyses. The sequences of D2–D3 segments of 28S rRNA gene were aligned with ClustalX 1.83 (Thompson et al., 1997), using default parameter values and were manually edited if necessary. Phylogenetic analyses of the sequence datasets were based on Bayesian inference (BI) using MrBayes 3.1.2 (Ronquist and Huelsenbeck, 2003). The best-fit model of DNA evolution was obtained using JModelTest V.2.1.7 (Darriba et al., 2012) with the Akaike Information Criterion (AIC). The best-fit model, the base frequency, the proportion of invariable sites, and the gamma distribution shape parameters and substitution rates in the AIC were then used in MrBayes for the phylogenetic analyses. The general time-reversible model with invariable sites and a gamma-shaped distribution (GTR + G) for the D2-D3 segments of 28S rRNA gene were run with four chains for 2 × 106 generations, respectively. The Markov chains were sampled at intervals of 100 generations. Two runs were conducted for analysis. After discarding burn-in samples and evaluating convergence, the remaining samples were retained for further analyses. The topologies were used to generate a 50% majority rule consensus tree. Posterior probabilities (PP) were given for appropriate clades. Pairwise divergences between taxa were computed as absolute distance values and as percentage mean distance valuesbased on whole alignment, with adjustment for missing data with PAUP* 4.0b 10 (Swofford, 2003). Trees were visualized using TreeView (Page, 1996).
An amended description of
Moreover, four new records of
Morphometric characters of the two populations of
Character\population | Dehdasht population | Baghmalek population | Total | ||||
---|---|---|---|---|---|---|---|
|
10 females | 5 J2 | 1 male | 10 females | 5 J2 | 20 females | 10 J2 |
L | 416 ± 36.6 (356–476) | 313 ± 9.8 (301–326) | 500 | 478 ± 42.5 (382–544) | 346 ± 21.8 (324–380) | 447 ± 50.1 (356–544) | 330 ± 23.7 (301–380) |
|
11.6 ± 0.7 (10.2–12.6) | 26.9 ± 1.9 (24.5–29.6) | 37.3 | 11.1 ± 0.8 (9.8–12.4) | 26.5 ± 1.5 (24.5–28.5) | 11.3 ± 0.8 (9.8–12.6) | 26.7 ± 1.6 (24.5–29.6) |
|
3.6 ± 0.3 (3.1–4.2) | 2.9 ± 0.1 (2.7–3.2) | 5.1 | 3.7 ± 0.1 (3.3–4) | 3.1 ± 0.1 (2.9–3.3) | 3.6 ± 0.2 (3.1–4.2) | 3 ± 0.2 (2.7–3.3) |
c | 12.7 ± 1.1 (11.1–15.1) | 8.7 ± 0.4 (8.2–9.3) | 9.4 | 12.7 ± 1.3 (11.1–15.1) | 9.9 ± 0.8 (8.5–10.6) | 12.7 ± 1.2 (11.1–15.1) | 9.3 ± 0.9 (8.2–10.6) |
|
2.7 ± 0.2 (2.4–3.1) | 4.8 ± 0.2 (4.5–5) | 4.1 | 2.9 ± 0.3 (2.5–3.6) | 4.2 ± 0.3 (3.6–4.7) | 2.8 ± 0.3 (2.4–3.6) | 4.5 ± 0.4 (3.6–5) |
V | 75.9 ± 2.2 (73.2–78.5) | – | – | 77.3 ± 1.5 (74.5–79.9) | – | 76.6 ± 1.9 (73.2–79.9) | – |
Stylet | 13.5 ± 0.5 (12.3–14.5) | 12.5 ± 0.3 (12–13) | 9.6 | 13.5 ± 0.7 (12.4–14.3) | 13.2 ± 0.6 (12.5–13.8) | 13.5 ± 0.6 (12.3–14.5) | 12.9 ± 0.5 (12–13.8) |
Conus | 6.7 ± 0.4 (6–7.5) | 6.2 ± 0.2 (6–6.6) | – | 7.1 ± 0.8 (6–8.3) | 6.9 ± 0.3 (6.5–7.3) | 6.9 ± 0.6 (6–8.3) | 6.5 ± 0.4 (6–7.3) |
m (conus/stylet %) | 49.8 ± 2.2 (46.6–52.9) | 49.4 ± 0.9 (48.4–50.7) | – | 52.8 ± 5.6 (44.4–62.9) | 52.5 ± 1.3 (51–54.4) | 51.3 ± 4.4 (44.4–62.9) | 50.9 ± 1.9 (48.4–54.4) |
Pharynx | 114 ± 12 (99–129) | 108 ± 8.7 (92–113) | 97 | 129 ± 9.2 (106–140) | 109 ± 5.7 (102–117) | 122 ± 12.8 (99–140) | 108 ± 7 (92–117) |
Median bulb | 68.3 ± 5.6 (60–78) | 60.4 ± 5.1 (56–69) | 45 | 70.9 ± 3.7 (62.7–76) | 55.6 ± 2.9 (52–60) | 69.6 ± 4.8 (60–78) | 58 ± 4.7 (52–69) |
MB | 59.9 ± 3.9 (55.2–66.6) | 56.2 ± 4.6 (51.8–61.6) | 46 | 55.1 ± 2.6 (51–59) | 50.9 ± 0.5 (50–51.3) | 57.5 ± 4.1 (51–66.6) | 53.6 ± 4.2 (50–61.6) |
Excretory pore | 88.9 ± 9.8 (77–104) | 77.2 ± 4.4 (71–83) | 70 | 96.3 ± 9 (72.4–103) | 78.2 ± 3.1 (75–82) | 92.6 ± 9.9 (72.4–104) | 77.7 ± 3.6 (71–83) |
Head-vulva | 316 ± 35.2 (261–373) | – | – | 370 ± 39.4 (284–435) | – | 343 ± 45.6 (261–435) | – |
Head-anus | 383 ± 34.9 (327–441) | 277.4 ± 10 (265–289) | 447 | 440 ± 41.7 (349–506) | 312 ± 21.7 (291–344) | 412 ± 47.6 (327–506) | 294 ± 24 (265–344) |
Tail length | 32.9 ± 3.3 (28–37) | 35.8 ± 1.3 (34–37) | 53 | 37.6 ± 3.4 (32.9–43) | 34.8 ± 2.7 (32–39) | 35.2 ± 4.1 (28–43) | 35.3 ± 2.1 (32–39) |
Body width | 35.8 ± 3.7 (30–41.5) | 11.6 ± 0.5 (11–12.5) | 13.4 | 43.1 ± 5.4 (35.2–55) | 13 ± 1.3 (12–15.5) | 39.4 ± 5.9 (30–55) | 12.3 ± 1.2 (11–15.5) |
Anal body width | 11.8 ± 0.8 (10.5–13.5) | 7.4 ± 0 (7.3–7.5) | 12.8 | 12.9 ± 0.9 (11.5–14.5) | 8.3 ± 0.5 (7.5–9) | 12.3 ± 1 (10.5–14.5) | 7.8 ± 0.5 (7.3–9) |
Annulus width | 1.2 ± 0.1 (1.0–1.4) | – | 1.4 | 1.0 ± 0.1 (0.9–1.3) | – | 1.1 ± 0.1 (0.9–1.4) | – |
Spicules | – | – | 21 | – | – | – | – |
Gubernaculum | – | – | 4.5 | – | – | – | – |
Measurements are in µm and in the form of average ± SD (range).
Morphometric characters of
Characters\species |
|
|
|
||
---|---|---|---|---|---|
|
8 females | 10 females | 5 males | 12 females | 6 males |
L | 335 ± 38.8 (263–368) | 358 ± 24.1 (330–400) | 353 ± 10.1 (340–367) | 424 ± 12.5 (406–446) | 449 ± 24.7 (412–488) |
|
20.7 ± 2.2 (15.4–22.5) | 25.2 ± 2.5 (21.1–29.3) | 28 ± 1.6 (26.1–30.3) | 25.1 ± 1.6 (22–27) | 33.2 ± 2 (30.8–36.1) |
|
4.1 ± 0.7 (2.8–5.3) | 3.5 ± 0.2 (3.1–3.8) | 3.5 ± 0.2 (3.3–3.9) | 4 ± 0.1 (3.8–4.2) | 4.5 ± 0.2 (4.1–4.8) |
|
12 ± 1.3 (9.3–13.2) | 12.7 ± 1.6 (10.1–15.6) | 11.1 ± 1 (10–12.5) | 11.4 ± 0.5 (10.7–12.5) | 10.5 ± 1.4 (8.5–12.8) |
|
2.9 ± 0 (2.8–3) | 3 ± 0.3 (2.5–3.6) | 3.1 ± 0.3 (2.5–3.6) | 3.6 ± 0.1 (3.3–3.9) | 3.9 ± 0.5 (3.2–4.6) |
V | 81.8 ± 2.4 (79.4–87.4) | 83.1 ± 0.7 (81.8–84.2) | – | 80.2 ± 1 (78.5–82.3) | – |
Stylet | 48.8 ± 1.4 (46.9–51.2) | 20.5 ± 1 (18.7–22) | – | 24.1 ± 0.5 (23–25) | – |
m (conus/stylet %) | 76.7 ± 1.2 (74.8–78.1) | 65 ± 2.4 (61.1–69.9) | – | 64.5 ± 1.3 (62.5–66.5) | – |
Pharynx | 82.5 ± 9.9 (67–93.5) | 99.8 ± 6.9 (91.7–112) | 100 ± 4.8 (93–105.6) | 104.6 ± 4.6 (98–112) | 99.1 ± 8.3 (85–109) |
MB | 73 ± 6.6 (65.8–80.5) | 56.4 ± 1 (55.1–58) | – | 56.3 ± 1 (54.7–58) | – |
Excretory pore | 77 ± 9 (65–89) | 82.5 ± 5.1 (77–89) | 74.6 ± 8.4 (67–88.7) | 91.6 ± 3.2 (87–96) | 86 ± 10.3 (66–95) |
Head-vulva | 274 ± 31.2 (209–300) | 298 ± 20.3 (274.6–332) | – | 340 ± 12.4 (319–360) | – |
Head-anus | 307 ± 38.8 (235–340) | 329 ± 23 (305–369) | 321 ± 9.5 (313–336) | 389 ± 11.4 (372–409) | 406 ± 20.7 (376–441) |
Tail length | 27.8 ± 0.5 (27–28.5) | 28.4 ± 3.9 (22.1–34.4) | 31.8 ± 3 (27–34.9) | 37 ± 1.9 (33–40) | 43.1 ± 7 (34–53) |
Body width | 16.2 ± 1.3 (13.9–17.4) | 14.2 ± 1.2 (12.5–16.3) | 12.5 ± 0.5 (11.8–13) | 16.9 ± 0.9 (15.5–18.5) | 2.8 ± 0.2 (2.5–3.2) |
Annulus width | 1.3 ± 0.1 (1.2–1.5) | 1.3 ± 0.1 (1.1–1.5) | 1.3 ± 0.1 (1.2–1.4) | 1.3 ± 0.1 (1.1–1.5) | 1.3 ± 0.1 (1.2–1.5) |
st/L × 100 | 14.7 ± 1.7 (13.1–18.2) | 5.7 ± 0.4 (5.1–6.4) | – | 5.7 ± 0.1 (5.5–5.8) | – |
Spicules | – | – | 23.4 ± 1.4 (22–25.2) | – | 24.8 ± 0.6 (24–25.5) |
Gubernaculum | – | – | 4.5 ± 0.4 (4.1–5.2) | – | 4.8 ± 0.2 (4.5–5) |
Measurements are in µm and in the form of average ± SD (range).
Morphometric characters of
Characters\species |
|
|
|
|
---|---|---|---|---|
|
8 females | 7 females | 5 males | 6 females |
L | 337 ± 26.7 (285–365) | 382 ± 41 (304–425) | 367 ± 25.3 (325–390) | 308 ± 24.1 (273–347) |
|
22.5 ± 1.4 (19.5–23.9) | 24.6 ± 2.1 (22.1–28.6) | 30.1 ± 2.5 (27–32.8) | 23.7 ± 2.2 (20.5–26.5) |
|
2.4 ± 0.1 (2.2–2.6) | 3.9 ± 0.3 (3.3–4.5) | 4.1 ± 0.4 (3.4–4.6) | 3.7 ± 0.3 (3.4–4.2) |
|
15.5 ± 2.5 (12.3–19.1) | 15.5 ± 1.7 (12.1–17.3) | 11.2 ± 0.4 (10.7–11.8) | 15.2 ± 1.5 (13–17.7) |
|
2.8 ± 0.2 (2.5–3.3) | 2.7 ± 0.1 (2.6–2.8) | 3 ± 0.2 (2.8–3.3) | 2.4 ± 0 (2.3–2.5) |
V | 75.7 ± 1.2 (74.6–78) | 85.6 ± 4.7 (83.4–96.4) | – | 80.5 ± 0.9 (79.1–82.1) |
Stylet | 76.7 ± 6.4 (61.3–82) | 25.4 ± 1.4 (22.7–26.7) | 11.7 ± 1 (10–13) | 30.2 ± 1 (28.9–32) |
m (conus/stylet %) | 89.5 ± 0.7 (88.2–90.7) | 63.3 ± 1.2 (61.2–64.9) | – | 68.9 ± 1.8 (66.7–71.1) |
Pharynx | 139 ± 10.7 (117–149) | 97.6 ± 6 (90.3–105.7) | 90 ± 12.2 (79–110) | 82.5 ± 5.1 (79–92.8) |
MB | 70.5 ± 1.4 (68–72.3) | 58.2 ± 1.4 (56.7–60.6) | – | 57.7 ± 3.2 (51.5–60.5) |
Excretory pore | 81.5 ± 5.5 (68–85) | 97.6 ± 6 (90.3–105.7) | 91 ± 7.3 (79–98) | 82.5 ± 5.1 (79–92.8) |
Head-vulva | 255.6 ± 20.8 (219.7–285) | 327 ± 39.4 (255–369) | – | 248 ± 19.5 (220–280) |
Head-anus | 315 ± 27.4 (264–345) | 357 ± 41 (279–401) | 335 ± 23 (297–357) | 287 ± 24.5 (252–327) |
Tail length | 22.1 ± 2.9 (19–27) | 24.5 ± 0.6 (23.5–25.1) | 32.6 ± 2.6 (28–34) | 20.2 ± 0.4 (19.5–21) |
Body width | 14.9 ± 0.5 (14.2–15.8) | 15.5 ± 1.9 (12.9–19.2) | 12.2 ± 0.5 (11.5–13) | 12.9 ± 1 (11.7–14.5) |
Annulus width | 1.2 ± 0.1 (0.9–1.3) | 1.4 ± 0.2 (1.2–1.7) | 1.3 ± 0.1 (1.2–1.4) | 1.2 ± 0.1 (1.1–1.3) |
st/L × 100 | 22.8 ± 1.2 (21.1–24.6) | 6.7 ± 0.5 (6.3–7.5) | 3.2 ± 0.3 (2.7–3.6) | 9.9 ± 0.9 (8.5–11.1) |
Spicules | – | – | 20.1 ± 0.8 (19.5–21.5) | – |
Gubernaculum | – | – | 4.5 ± 0.4 (4.2–5) | – |
Measurements are in µm and in the form of average ± SD (range).
Morphometric characters of
Characters\species |
|
|
|
|
---|---|---|---|---|
|
5 females | 5 females | 22 females | 17 females |
L | 303 ± 17.2 (283–325) | 405 ± 28.1 (363–437) | 358 ± 44.4 (281–451) | 325 ± 18.1 (291–355) |
|
25.6 ± 0.6 (25–26.4) | 20.9 ± 1.6 (18.7–23.4) | 22.7 ± 1.9 (17.2–26.5) | 23.2 ± 1.5 (20.7–27.1) |
|
2.4 ± 0.1 (2.2–2.5) | 4.3 ± 0.3 (4–4.7) | 3.8 ± 0.3 (3–4.6) | 3.9 ± 0.2 (3.5–4.3) |
|
8.6 ± 0.8 (7.4–9.8) | 13.2 ± 1 (11.5–14.5) | 10.9 ± 0.6 (10–12.6) | 16.1 ± 1 (14.2–17.7) |
|
3.2 ± 0.1 (3–3.4) | 3 ± 0.1 (2.7–3.2) | 3.4 ± 0.2 (2.9–4.1) | 2.4 ± 0.1 (2.2–2.5) |
V | 75.4 ± 1.9 (72.2–77.3) | 81.8 ± 0.8 (80.4–83) | 81.2 ± 2 (75.3–84.3) | 85.2 ± 1 (83.4–87.4) |
Stylet | 80.1 ± 2.2 (76.7–82.6) | 25.4 ± 0.5 (24.3–25.9) | 16.9 ± 0.8 (15.5–18.9) | 14.1 ± 0.6 (12.8–14.9) |
m (conus/stylet %) | 90.5 ± 5.3 (87.6–100) | 62.2 ± 2.8 (58.4–66.5) | 61.8 ± 2 (57.6–65.8) | 62.5 ± 2.6 (57.3–69.9) |
Pharynx | 124.4 ± 6.5 (113.2–128.9) | 92.6 ± 5.1 (88.1–102.1) | 92.5 ± 6.2 (79.6–114.6) | 82.1 ± 3.1 (76.4–87.8) |
MB | 76.6 ± 3.3 (74.1–82.3) | 58.6 ± 2.6 (56.5–63.6) | 54.1 ± 2.1 (45.6–56.4) | 50.5 ± 1.9 (45.5–53.9) |
Excretory pore | 83.4 ± 2.3 (81.7–87.4) | 92.6 ± 5.1 (88.1–102.1) | 86.2 ± 4.8 (76–102) | 72.7 ± 2.6 (69–78) |
Head-vulva | 229 ± 16.5 (208–247) | 331 ± 25.1 (292–358) | 291 ± 32.5 (220–346) | 277 ± 17.2 (246–304) |
Head-anus | 268 ± 18.6 (245–292) | 374 ± 28 (332–406) | 325 ± 41.8 (254–413) | 305 ± 18.1 (270–335) |
Tail length | 35 ± 1.8 (33–38) | 30.6 ± 1.5 (29.1–33.1) | 32.5 ± 2.8 (27–38) | 20.1 ± 0.5 (19–21.5) |
Body width | 11.8 ± 0.6 (10.9–12.5) | 19.3 ± 2.1 (16.8–22.6) | 15.7±1.7 (13.5–21.2) | 14 ± 0.9 (11.4–15.4) |
Annulus width | 0.9 ± 0.1 (0.8–1.1) | 1.5 ± 0.1 (1.4–1.6) | 1.1 ± 0.1 (0.9–1.4) | 1.3 ± 0.1 (1.1–1.5) |
st/L × 100 | 26.5 ± 0.8 (25.4–27.4) | 6.3 ± 0.5 (5.6–7.0) | 4.8 ± 0.5 (3.9–5.8) | 4.4 ± 0.3 (3.8–4.7) |
Measurements are in µm and in the form of average ± SD (range).
Posterior end of females of
Posterior end of second-stage juveniles of
Diagnostic characters of
Diagnostic drawings of
The 50% majority rule consensus tree from Bayesian analysis generated from the D2–D3 expansion segments of 28 S rRNA gene dataset under the GTR + I + G model. Posterior probabilities for BI analysis more than 50% are given for appropriate clades. The new sequencesare indicated in bold.
The body is obese particularly in the region between pharynx and vulva, regularly tapering towards both ends, strongly ventrally curved. Cuticular annuli are 0.9 to 1.4 µm wide at mid-body, lateral field is indistinct. The cephalic region is hemispherical, lacking perioral disc and transverse annuli, continuous with the body contour; cephalic framework is slightly sclerotized. Stylet is strong, conus is nearly as long as shaft, but sometimes slightly shorter or longer; basal knobs are round, slightly sloping backward, about 3 µm across. DGO is situated at 3.5 to 5.0 µm posterior the stylet knobs. Procorpus amalgamated with median bulb which has elongate-oval distinct valvular apparatus; median bulb is 14 to 23 µm in width; basal bulb is pyriform. Isthmus is short and narrow; nerve ring is located at anterior end of isthmus. Excretory pore is located at 72 to 104 µm from the anterior end (18–25% of body length) at the end of isthmus; duct with wide lumen leads backward to a large renette cell. The reproductive system is monodelphic-prodelphic. Ovary is well developed, outstretched without flexures reaching the basal pharyngeal posterior bulb. Spermatheca is round, globular to slightly oval sperm cells; short post-vulval is present. Vulva is a transverse slit flush with body, without cuticular flaps, at 89 to 114 µm anterior to tail terminus. Vagina is perpendicular with body or directed anteriorly. Anus is distinct with raised lips. Tail is arch-shaped, curved ventrally with a finely rounded terminus (Dehdasht population) and a bluntly rounded, indented or finely rounded terminus (Baghmalek population).
Only one male was found in Dehdasht population. Body is vermiform, open C-shaped habitus after fixation. Lateral field is indistinct, when viewed under light microscope. Cuticular annuli are 1.4 µm apart at mid-body. The cephalic region is round, lacking perioral disc and transverse annuli. Stylet and pharynx are reduced; median and basal pharyngeal bulbs are not distinct, having single testis, anteriorly outstretched. Spicules are slightly arcuate ventrally, protruded. Gubernaculum is short and simple, trough-shaped in lateral view. Tail is elongated conical, with a terminal projection.
Body is slender, ventrally curved to C-shaped habitus after fixation. Lateral field is usually indistinct, with four longitudinal lines. The cephalic region is conical, smooth, and continuous with the body contour. Stylet is 2.1 to 2.6 head widths long; conus is slightly longer than shaft; basal knobs are round. Dorsal pharyngeal orifice is 3.7 to 4.2 µm behind the stylet knobs. Pharynx is normally developed, median bulb is oval, posterior bulb is saccate to pyriform. Excretory pore is located at 75 to 82 µm from anterior end. Tail is ventrally arcuate, regularly tapering, terminus mostly with a slender acute projection in both populations, the projection is slightly shorter in Baghmalek specimens.
Mature females are slightly stout, body tapers posterior to vulva, body ventrally curved or open to close C-shaped after fixation. Cuticle is fine but distinct transverse annules, 1.1 to 1.5 µm wide in mid-body. Lateral field is with four lines, with equal intervals. Cephalic region is continuous to the body contour, almost rounded with delicate transverse striations, and submedian lobes on head are not visible in lateral view. Stylet is long and slender, slightly curved, and basal knobs are rounded and 2.2 to 2.9 µm in width. Deirids are distinct, opposite to excretory pore in some individuals; the pore is located at the level of pharyngeal posterior bulb. Vulva flush with body, with small cuticular flaps usually lower than lips. Reproductive system is monodelphic-prodelphic and ovary outstretched. Spermatheca is oval, filled with globular sperm. Post-vulval uterine sac is not present. Tail is convex-conoid, often ventrally curved, with acute to finely rounded terminus. Phasmids are not observed.
Not found.
Remarks: morphometric and morphological characteristics of the Iranian population fit well with those of the original description (Oostenbrink, 1953) and other populations of
The body tapers suddenly posterior to vulva; the body is ventrally curved to C-shaped after fixation. Cuticle is with fine transverse annules, 1.1 to 1.5 µm wide in mid-body. Lateral field is with four lines. Cephalic region is continuous to the body contour, truncated to slightly raised at anterior end; submedian lobes are on head, appeared very small in lateral view. Stylet is medium-sized, and basal knobs are rounded to slightly directed backward, being 2.2 to 3.2 µm in width. Excretory pore is located at the level of pharyngeal posterior bulb. The posterior lip of vulva is lower than the anterior one, with distinct raised semi-circular cuticular flaps. The reproductive system is monodelphic-prodelphic, spermatheca oval, and filled with globular sperm. Post-vulval uterine sac is short. Tail is convex-conoid, often slightly ventrally curved, with finely to bluntly rounded terminus. Phasmids are not observed. Fourth-stage juvenile (J4) is similar to female in general characteriztics, but lacking stylet.
Similar to female in general characteriztics, the body is almost straight to slightly ventrally curved after fixing. Cuticular annules are 1.2 to 1.4 µm apart in mid-body. Lateral field is with four lines. Stylet is absent and pharynx degenerate. Spicules are slightly curved ventrally, protruding from the body in some individuals; gubernaculum is simple. Tail is conoid, slightly curved ventrally or dorsally, with finely rounded terminus.
Remarks: comparing with the original description of
The body tapers gradually at both ends; the body is ventrally curved to C-shaped after fixation. Cuticle is with distinct transverse annules, 1.2 to 1.5 µm wide in mid-body. Lateral field is with four equally-distant lines; in cross sections, each three bands protrude markedly. The cephalic region is truncated conical; submedian lobes protrude on head surrounding the oral aperture when observed from lateral view. Cephalic framework is with relatively strong sclerotization. Stylet is robust with well-developed basal knobs sloping backward, 4.1 to 4.6 µm in width. Excretory pore is located at level of pharyngeal posterior bulb. Vulva is a deep transverse slit, with large raised semi-circular cuticular flaps. The reproductive system is monodelphic-prodelphic, spermatheca on lateral side of the gonad, oval to elongated shape, and filled with globular sperm. Post-vulval uterine sac is absent. Tail tapers gradually and is slightly ventrally curved, with subacute, finely rounded, or bluntly rounded terminus. Phasmids are not observed.
Similar to female in general characteristics, the body is almost straight to ventrally or dorsally curved after fixing. Cuticular annules are 1.2 to 1.5 µm apart in mid-body. Lateral field is with four lines. Stylet is lacking; pharynx degenerates and is less developed, only a simple outline can be distinguished. Spicules are slightly curved ventrally, gubernaculum is simple, and penial tube bears a distinct appendage on its posterior part. Tail is elongated conoid, slightly curved ventrally, with finely rounded terminus.
Remarks: Raski (1973) proposed
The body is ventrally curved to open C-shaped after fixation, more strongly curved posterior to vulva. Cuticle is with fine transverse annules, 0.9 to 1.3 µm wide in mid-body. Lateral field is with four lines. The cephalic region is truncated to slightly raised at anterior end; submedian lobes on head are distinct in lateral view. Stylet is long and flexible, basal knobs are large and rounded, being 3.6 to 5.5 µm in width. Excretory pore is located at the level of pharyngeal median bulb and anterior to its valve. Vulva flush with body, lacking cuticular flaps. The reproductive system is monodelphic-prodelphic, spermatheca small, without sperm, and attached to the gonad from lateral side. Post-vulval uterine sac is absent. Tail is convex-conoid, often ventrally curved, with finely rounded terminus. Phasmids are not observed. Fourth-stage juvenile (J4) is similar to female in general characteriztics, but with reduced stylet (14–19 µm) bearing small basal knobs and having a tail with bluntly rounded terminus (Table 5).
Not found.
Remarks: the present population is similar to the previously recovered populations of
The D2–D3 alignment was 596 bp long and consisted of 88 sequences as ingroups and three sequences including
The BI tree revealed good separation between the four subfamilies in trees inferred from 28 S rRNA gene sequences. Four distinct clades were formed, congruent with the morphological classification of the subfamilies in Ghaderi et al. (2016). Representatives of Paratylenchinae (Thorne, 1949) included several species of
Together with another sequence of
The sequences of the four
Different populations of the three
Gomez-Barcina and Castillo (1990) synonymized
Raski (1991) distinguished the three species based on the same characters mentioned by Minagawa (1983); they used morphometric differences of female tail, male gubernaculum and J2 body size for separating of
Inserra et al. (1993) found populations of
Two populations of
The other interesting result inferred from the phylogenetic analysis of the present study, distant position of the three sequences of
From the five sequenced
Raski (1973) distinguished
Ghaderi et al. (2014, 2016) provided a grouping for all
The first cluster of subclade IB contains
As a starting point for a detailed analysis and molecular characterization of the genus