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Labrys khuzestanensis n. sp. (Figs 1–3) Measurements: see Table 1. Female: Body straight to slightly ventrally arcuate after heat relaxation. Cuticle finely annulated, annulus ca 1 μm wide at midbody. Lateral field distinct, having two incisures with smooth margins under SEM. Cephalic region smooth, continuous with the adjacent part of body, 4.5 μm wide and 2.1–2.3 μm high, trapezoid under LM, dorsoventrally flattened, with protuberant large and elongate labial plate under SEM. The plate is laterally extended and dorso-ventrally not constricted. In lateral view under LM, the plate seems as a V-shaped piece (Fig. 2D; hardly visible due to small size). The oral plate small, laterally elongate, containing labial sensillae, with small and elevated oral opening at the center. Amphidial openings as longitudinal slits, beginning near oral plate, laterally extending to the labial plate corners and confined to it. Stylet delicate, slender, conus shorter than the shaft, comprising ca 33% of its total length, the knobs rounded and small, slightly posteriorly sloping. Dorsal pharyngeal gland orifice (DGO) 1–2 μm from the base of the stylet. Procorpus slender, median bulb moderately developed, elongate fusiform with small valvular apparatus, isthmus narrow, slender, pharyngeal bulb small, pyriform and offset. Cardia small, domeshaped. Nerve ring encircling anterior part of isthmus, 57 to 76 μm from anterior end. Excretory pore wide with sclerotized duct, at the distance between the nerve ring and anterior part of pharyngeal bulb. Reproductive system monodelphic-prodelphic, composed of an outstretched ovary occupying 13–15% of total body length, the oocytes mostly arranged in single row. The border of oviduct, spermatheca and the cell arrangement of crustaformeria indistinct. Vagina with thin wall, perpendicular to body axis and straight or slightly anteriorly sloping. Postvulval uterine sac (PUS) ca 0.6 to 1.0 times corresponding body diameter long. Vulva a small transverse slit with very small lateral flaps. Tail elongate filiform, very gradually narrowing toward end, 1.9 to 3.0 times longer than vulva–anus distance, with finely rounded tip. 1 Distance between anterior end of body and center of median pharyngeal bulb as percentage of pharynx length. 2 Postvulval uterine sac/body width Male: Unknown. Type habitat and locality. The rhizospheric soil of a palm tree (Phoenix dactylifera L.) in city of Ahvaz, Khuzestan province, southwestern Iran, collected during 2016. GPS coordinates: 31°28.582′N, 48°37.394′E. Etymology. The specific epithet refers to Khuzestan province, the original geographic point of which the new species was recovered from. Type material. Holotype female and four paratype females were deposited at Nematode Collection of the Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran (the slide code: TM5043). Three paratype females were deposited at Ghent University Museum, Zoology Collections, Ghent, Belgium (UGMD _104411 and UGMD _ 104412). Two paratype females were deposited at the Nematode Collection of the Department of Animal Biology, Plant Biology and Ecology of the University of Jaén, Jaén, Spain) (Collection ID: Iran 011) (one paratype female was used to prepare SEM photos). Diagnosis and relationships. Labrys khuzestanensis n. sp. is mainly characterized by large and prominent labial plate as revealed by SEM and trapezoid cephalic region under LM. It is further characterized by 590–675 μm long females having a finely annulated cuticle under LM, lateral field with two incisures, cephalic region dorsoventrally flattened and smooth, labial plate not constricted at middle, elongate, laterally extending and appearing as V-shaped piece in lateral view, amphidial openings long slits confined to the labial plate, stylet 7.5–9.0 μm long, median bulb elongate fusiform with small valvular apparatus, excretory pore wide, with sclerotized duct and tail elongate filiform with finely rounded tip. Compared to four currently known species of the genus, the new species has a remarkably large and prominent labial plate and trapezoid cephalic region under LM (vs. rounded). The detailed morphological comparisons of the new species with Labrys members are as follows: From L. chinensis Qing & Bert, 2018 by distinctly annulated cuticle under LM (vs. smooth), greater a ratio (53.6– 74.8 vs. 37.7–48.7), lower c ratio (2.6–3.2 vs. 3.5–4.4), greater cʹ ratio (23.5–32.9 vs. 13.3–20.3), more anteriorly located vulva (V = 48.0–54.3 vs. 54–60), greater tail length/vulva to anus distance ratio (1.9–3.0 vs. 1.3–1.7), longer tail (188–237 vs. 132–171 μm) and difference in tail end morphology (finely rounded tip vs. broadly rounded). From L. fujianensis Qiao, Bai, Wang, Hou, Chen, Xiao, Liu, Bert & Qing, 2019a by laterally elongate oral plate (vs. dorsoventrally, after its SEM data) and slightly longer body (590–675 vs. 524–599 μm). From L. filiformis Panahandeh, Abolafia, Pourjam, Jahanshahi Afshar, Giblin-Davis & Pedram, 2018 by its distinct annulated cuticle under LM (vs. smooth), longer body (590–675 vs. 425–463 μm), greater a ratio (53.6–74.8 vs. 38.7–46.2), greater b ratio (5.7–7.4 vs. 4.9–5.7), lower c ratio (2.6–3.2 vs. 3.5–4.0), greater cʹ ratio (23.5– 32.9 vs. 13.2–15.9), more anteriorly located vulva (V = 48.0–54.3 vs. 57.7–61.5), lower Uʹ ratio (74.6–79.8 vs. 79.9–84.1) and longer tail (188–237 vs. 106–127 μm). From L. fuzhouensis Qiao, Bai, He, Chen, Xiao, Cheng, Liu, Braun-Miyara & Qing, 2019b by longer body (590–675 vs. 495–564 μm), greater a ratio (53.6–74.8 vs. 40.6–53.1), longer neck (86–108 vs. 72–80 μm) and lacking male (vs. present). Phylogenetic analyses. To study of the phylogenetic affinities of the new species with other genera/species of the family Tylenchidae, its partial SSU rDNA was used in corresponding phylogenetic analysis. A total number of 75 species/isolates (including the newly obtained SSU sequence of the new species and three aphelenchid+a phelenchoidid outgroups) were selected for these analyses (Bayesian inference and ML trees). The alignment of SSU dataset had 1824 total characters with 981 variable characters. The average nucleotide composition was as follows: 24.5% A, 22.9% C, 28.3% G, and 24.3% T. Figure 4 represents the Bayesian phylogenetic tree inferred using the abovementioned dataset. In this tree, the new species and three previously described species viz. Labrys chinensis (KY776630, KY776631, KY776632, KY776633), L. fuzhouensis (MK039731, MK039732), and L. filiformis (MG686086) formed a clade and Discotylencus lorestanensis Mehrabian, Azizi, Bazgir & Darvishnia, 2017 (KU878152, KU878153) is the closest taxon to these species. The other species of Labrys, L. fujianensis occupied a distant placement to them.

Konani, Ehsan, Panahandeh, Yousef, Pourjam, Ebrahim, Álvarez-Ortega, Sergio, Pedram, Majid (2018): Two rare species of tylenchids, Discotylenchus biannulatus n. sp. and Labrys chinensis Qing & Bert, 2018 (Nematoda: Tylenchidae) from western Iran. Zootaxa 4413 (2): 260-270, DOI: https://doi.org/10.11646/zootaxa.4413.2.2

Discotylenchus biannulatus n. sp. (Figs. 1–3) Description. Measurements. See Table 1. Female: Body straight to slightly ventrally curved after heat relaxation. Cuticle finely annulated, annules ca. 1–2 µm wide at mid-body. Lateral fields with four incisures, outer lines partly areolated at anus/tail region in SEM images, 2–3 µm wide at mid-body, approximately 20% of body diameter. Lip region continuous with body contour, 5–6 µm wide and 3–4 µm high, dorso-ventrally flattened, smooth, having two annuli in the proximal end and a prominent perioral disc under SEM. Amphidial openings as longitudinal slits on lateral sides of the head. Stylet delicate, with conus shorter than the shaft comprising ca 32.7% of stylet total length; knobs small, slightly sloping posteriad. Dorsal gland orifice (DGO) 1–2 µm from base of stylet. Procorpus slender, joining to an ellipsoid muscular metacorpus with distinct valvular apparatus, located at 39–43% of total pharynx length; isthmus elongated and narrow; and basal bulb with slight variation in shape, saccate to bottle-shaped, 14–18 µm long and 7–9 µm wide. Cardia small. Nerve ring encircling anterior half of isthmus, 63–68 µm from anterior end. Excretory pore situated at the level of the middle of the isthmus, posterior to hemizonid. Deirids distinct and situated 4–6 annuli posterior to excretory pore. Reproductive system monodelphic-prodelphic, composed of an outstretched ovary occupying 23–26% of the body length, oocytes mainly in a single row, oviduct short, spermatheca rounded and empty, crustaformeria hardly visible, uterus tubular, vagina straight with thin walls; PUS length about 0.6–0.8 times vulval body width, vulva a transverse slit lacking any differentiation. Tail filiform, gradually tapering to a more or less pointed end. Male: not found. Type habitat and locality. Recovered from the rhizosphere of wheat, Giloran region, city of Khorram-Abad, Lorestan province, western Iran. GPS coordinates: N 33 27 ʹ 51.53 and E 48 18 ʹ 17.99. Etymology. The specific epithet refers to two unusual annuli at the anterior end of the cephalic region of the new species. Type material. Holotype and five paratypes deposited at the Ghent University Museum, Zoology Collection, Belgium. Diagnosis and relationships. Discotylenchus biannulatus n. sp. is characterized by its dorso-ventrally flattened smooth lip region having two proximal annuli and a distinct rectangular perioral disc, short longitudinal amphidial slits, lateral field with four incisures, stylet 9–10 µm long, empty spermatheca and short PUS, and filiform female tail with pointed end. With four lines in the lateral field, the new species can be compared with three known species of the genus: D. attenuatus Siddiqi, 1980, D. brevicaudatus and D. discretus. The new species can be distinguished from these species by its smooth cephalic region with two annuli at the anterior end. In addition, Discotylenchus biannulatus n. sp. differs from D. attenuatus by having longer body (675–708 vs 330–400 µm), longer stylet (9–10 vs 6.0–6.5 µm), longer tail (155–161 vs 68–96 µm) and higher cʹ ratio (14.1–16.1 vs 9–12). It can be distinguished from D. brevicaudatus by its dorso-ventrally flattened cephalic region (vs rounded, according to SEM data provided by Yaghoubi et al. 2016), longer body (675–708 vs 320–466 µm), longer stylet (9–10 vs 6–8 µm), more anteriorly located vulva (V = 59.5–60.6 vs 68–73), longer tail (155–161 vs 35–77 µm), smaller c ratio (4.2–4.5 vs 5.9–9.8), higher cʹ ratio (14.1–16.1 vs 4.5–9.6) and filiform tail with pointed end (vs thick with rounded end). Finally, compared to D. discretus, the new species has dorso-ventrally flattened cephalic region (vs rectangular, smooth, according to SEM data provided by Yaghoubi et al. 2016), longer stylet (9–10 vs 7–9 µm), more anteriorly located vulva (V = 59.5–60.6 vs 63–67), longer tail (155–161 vs 80–115 µm), smaller c ratio (4.2–4.5 vs 5.0–6.2), and higher cʹ ratio (14–16 vs 9–11). Remarks. The presently described new species was recovered from an agricultural wheat field usually plowed annually. Detailed SEM studies helped establish its generic identity, but further samplings to get fresh material for molecular phylogenetic studies failed. It has a unique head morphology, however, not reported or illustrated to date for any members of Tylenchidae. Light microscope observations at first indicated the presence of an anterior disk, also confirmed in SEM studies, and all other morphological characters (especially longitudinal amphidial slits) supported its placement under the genus Discotylenchus. Future molecular studies will help determine the phylogenetic affinities of this species.

Discotylenchus biannulatus n. sp. (Figs. 1���3) Description. Measurements. See Table 1. Female: Body straight to slightly ventrally curved after heat relaxation. Cuticle finely annulated, annules ca. 1���2 ��m wide at mid-body. Lateral fields with four incisures, outer lines partly areolated at anus/tail region in SEM images, 2���3 ��m wide at mid-body, approximately 20% of body diameter. Lip region continuous with body contour, 5���6 ��m wide and 3���4 ��m high, dorso-ventrally flattened, smooth, having two annuli in the proximal end and a prominent perioral disc under SEM. Amphidial openings as longitudinal slits on lateral sides of the head. Stylet delicate, with conus shorter than the shaft comprising ca 32.7% of stylet total length; knobs small, slightly sloping posteriad. Dorsal gland orifice (DGO) 1���2 ��m from base of stylet. Procorpus slender, joining to an ellipsoid muscular metacorpus with distinct valvular apparatus, located at 39���43% of total pharynx length; isthmus elongated and narrow; and basal bulb with slight variation in shape, saccate to bottle-shaped, 14���18 ��m long and 7���9 ��m wide. Cardia small. Nerve ring encircling anterior half of isthmus, 63���68 ��m from anterior end. Excretory pore situated at the level of the middle of the isthmus, posterior to hemizonid. Deirids distinct and situated 4���6 annuli posterior to excretory pore. Reproductive system monodelphic-prodelphic, composed of an outstretched ovary occupying 23���26% of the body length, oocytes mainly in a single row, oviduct short, spermatheca rounded and empty, crustaformeria hardly visible, uterus tubular, vagina straight with thin walls; PUS length about 0.6���0.8 times vulval body width, vulva a transverse slit lacking any differentiation. Tail filiform, gradually tapering to a more or less pointed end. Male: not found. Type habitat and locality. Recovered from the rhizosphere of wheat, Giloran region, city of Khorram-Abad, Lorestan province, western Iran. GPS coordinates: N 33 27 �� 51.53 and E 48 18 �� 17.99. Etymology. The specific epithet refers to two unusual annuli at the anterior end of the cephalic region of the new species. Type material. Holotype and five paratypes deposited at the Ghent University Museum, Zoology Collection, Belgium. Diagnosis and relationships. Discotylenchus biannulatus n. sp. is characterized by its dorso-ventrally flattened smooth lip region having two proximal annuli and a distinct rectangular perioral disc, short longitudinal amphidial slits, lateral field with four incisures, stylet 9���10 ��m long, empty spermatheca and short PUS, and filiform female tail with pointed end. With four lines in the lateral field, the new species can be compared with three known species of the genus: D. attenuatus Siddiqi, 1980, D. brevicaudatus and D. discretus. The new species can be distinguished from these species by its smooth cephalic region with two annuli at the anterior end. In addition, Discotylenchus biannulatus n. sp. differs from D. attenuatus by having longer body (675���708 vs 330���400 ��m), longer stylet (9���10 vs 6.0���6.5 ��m), longer tail (155���161 vs 68���96 ��m) and higher c�� ratio (14.1���16.1 vs 9���12). It can be distinguished from D. brevicaudatus by its dorso-ventrally flattened cephalic region (vs rounded, according to SEM data provided by Yaghoubi et al. 2016), longer body (675���708 vs 320���466 ��m), longer stylet (9���10 vs 6���8 ��m), more anteriorly located vulva (V = 59.5���60.6 vs 68���73), longer tail (155���161 vs 35���77 ��m), smaller c ratio (4.2���4.5 vs 5.9���9.8), higher c�� ratio (14.1���16.1 vs 4.5���9.6) and filiform tail with pointed end (vs thick with rounded end). Finally, compared to D. discretus, the new species has dorso-ventrally flattened cephalic region (vs rectangular, smooth, according to SEM data provided by Yaghoubi et al. 2016), longer stylet (9���10 vs 7���9 ��m), more anteriorly located vulva (V = 59.5���60.6 vs 63���67), longer tail (155���161 vs 80���115 ��m), smaller c ratio (4.2���4.5 vs 5.0���6.2), and higher c�� ratio (14���16 vs 9���11). Remarks. The presently described new species was recovered from an agricultural wheat field usually plowed annually. Detailed SEM studies helped establish its generic identity, but further samplings to get fresh material for molecular phylogenetic studies failed. It has a unique head morphology, however, not reported or illustrated to date for any members of Tylenchidae. Light microscope observations at first indicated the presence of an anterior disk, also confirmed in SEM studies, and all other morphological characters (especially longitudinal amphidial slits) supported its placement under the genus Discotylenchus. Future molecular studies will help determine the phylogenetic affinities of this species., Published as part of Konani, Ehsan, Panahandeh, Yousef, Pourjam, Ebrahim, ��lvarez-Ortega, Sergio & Pedram, Majid, 2018, Two rare species of tylenchids, Discotylenchus biannulatus n. sp. and Labrys chinensis Qing & Bert, 2018 (Nematoda: Tylenchidae) from western Iran, pp. 260-270 in Zootaxa 4413 (2) on pages 261-264, DOI: 10.11646/zootaxa.4413.2.2, http://zenodo.org/record/1226931, {"references":["Siddiqi, M. R. (1980) Two new nematode genera, Safianema (Anguinidae) and Discotylenchus (Tylenchidae), with descriptions of three new species. Proceedings of the Helminthological Society of Washington, 47, 85 - 94.","Yaghoubi, A., Pourjam, E., Alvarez-Ortega, S. Liebanas, G., Atighi, M. R. & Pedram, M. (2016) Discopersicus n. gen., a New Member of the Family Tylenchidae Orley, 1880 with Detailed SEM Study on Two Known Species of the Genus Discotylenchus Siddiqi, 1980 (Nematoda; Tylenchidae) from Iran. Journal of Nematology, 48, 214 - 221. https: // doi. org / 10.21307 / jofnem- 2017 - 029"]}

Malenchus geraerti n. sp. Figs 1���3 The new species is named after Prof. Etienne Geraert, the pioneer and outstanding scientist in the taxonomy of Tylenchidae. Measurements, see Table 1. Female. Body slightly ventrally curved after fixation, markedly narrowing from the level of vulva to distal end. Cuticle coarsely annulated, annuli 2.1���2.3 ��m wide at mid-body. Lateral field a plain band (i.e. composed of two incisures), raised in cross section, constricted at the junction with body (Fig. 3B, arrows), originating at about the level of the middle of the stylet shaft in its resting position. Lip region continuous with body contour; not conspicuously narrower than the adjacent body, 5���7 ��m wide, 3���4 ��m high, bearing 3���4 annuli. Amphidial openings S-shaped slits, starting from labial plate, extending posteriorly, markedly narrowing and reaching base of the head (extending to the weakly sclerotized cephalic framework). Stylet shaft moderately developed, conus much finer, knobs directed posteriorly. Dorsal gland orifice (DGO) close to knobs. Excretory pore (ex. pore) at the level of pharyngeal bulb, slightly variable in position, 91���94 ��m from anterior end. Hemizonid 92 ��m (n = 3) and nerve ring 63���75 ��m from anterior end. Pharynx with slender procorpus, muscular, rounded to ellipsoid metacorpus with well-developed valve and corresponding plates at 43���49 ��m from anterior end, slender/narrow isthmus and saccate pharyngeal bulb 13���18 �� 8���11 ��m. Reproductive system mono-prodelphic, ovary outstretched, oocytes mostly in single file, except in germinal zone, oviduct short, spermatheca elongate-rounded, filled with small spheroid sperm cells, offset and sometimes appearing as bilobed (with depression or constriction at middle), crustaformeria and uterus not clearly discernible from each other. Vagina perpendicular to body axis, with moderately sclerotized walls. Small, undifferentiated postvulval uterine sac (PUS) present. Vulva sunken inside body, in the form of a transverse slit, with large epiptygma and no flaps. Prophasmid barely visible, located 14 ��m anterior to vulval opening (n = 1). Vulva���anus distance 64���77 ��m, or 0.8���1.1 times the tail length. Tail conical, tapering gradually to a more or less pointed tip. Male. About half as frequent as females in the studied population. General morphology similar to that of female, except in sexual characters. Testis single, outstretched. Spicules tylenchoid, narrow and slender, slightly arcuate distally, 17���22 ��m long with rounded capitulum, slender shaft and blade narrowing toward distal end. Gubernaculum small, 4���6 ��m. Bursa cloacal, 26���43 ��m long, with smooth margin. Tail similar to that of female. Type Habitat And Locality. Recovered from soil samples collected about rhizosphere of forest trees in forests of Gilan province, northern Iran. GPS coordinates: 37��7��30.719����N, 49��39��25.742����E. Type Material. Five females (holotype and paratypes) and five males deposited in the Nematode Collection of the Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran. Five paratype females and two males deposited at each of the following collections: WANECO collection, Wageningen, The Netherlands, and UGent Nematode Collection of the Nematology Research Unit, Department of Biology, Ghent University, Ghent, Belgium. Diagnosis And Relationships. The new species belongs to the subgenus Malenchus owing to its amphidial opening characteristics (S-shaped in lateral view, wide at anterior end, narrowing distally and reaching to the base of the head), and two lateral lines, forming a plain band under light microscopy. It is further characterized by having short-bodied females, lateral field origin at about the middle of the stylet shaft, muscular, rounded to ellipsoid metacorpus with well-developed valve and valvular plates, small PUS, vulva sunken in body with large epiptygma and no flap, conical tail, tapering gradually to a more or less pointed tip, functional males with 17���22 ��m tylenchoid spicules, adcloacal bursa with smooth margin and tail similar to that of female. Morphologically, the new species is similar to five known Malenchus species: M. fusiformis (Thorne & Malek, 1968) Siddiqi, 1979, M. machadoi (Andr��ssy, 1963) Andr��ssy, 1968, M. pachycephalus Andr��ssy, 1981, M. solovjovae Brzeski, 1989 and M. undulatus but most closely resembles M. pachycephalus forming a morphologically-similar cryptic species pair. Compared to M. fusiformis, a poorly known species of the genus described based only on one female and only known from its type locality (Geraert 2008), the new species has a longer body (439���489 vs 350 ��m), narrower annuli (2.1���2.3 ��m wide at mid-body vs 3 ��m), posteriorly directed stylet knobs (vs rounded) and lacks vulval membranes (vs having obscure lateral membranes). Compared to M. machadoi, the new species has a shorter body (439���489 vs 520���560 ��m), lip region continuous with body contour (vs markedly narrower), annuli 2.1���2.3 ��m wide at mid-body (vs 1.6���1.8 ��m) and median bulb with distinct valves (vs very small or indistinct valves, as described by Andr��ssy 1968). Compared to M. pachycephalus, besides differences in partial SSU and LSU rDNA sequences and divergent placement in the corresponding phylogenetic trees, the new species differs in the nature of the median bulb (welldeveloped with valvular plates vs very weakly developed, without valve), stylet knobs (symmetrical vs slightly asymmetrical), lateral field margin (smooth vs crenate), pharynx length (93���108 vs 86���90 ��m) and lacks vulval flaps (vs small dikes present). Furthermore, the raised lateral fields of the new species are separated from the rest of the body by a sharp constriction (Fig. 3B, arrows); this demarcation is lacking in M. pachycephalus as illustrated by Qing et al. (2017). Compared to M. solovjovae, the new species has a well-developed stylet and corresponding knobs and welldeveloped valve in the median bulb. Compared to M. undulatus, besides differences in SSU and LSU rDNA sequences and distant positions in the corresponding phylogenetic trees, the new species has annuli 2.1���2.3 ��m wide (vs 1.7���1.9), plain lateral field margins (vs deeply crenate), lip region continuous with body contour (vs distinctly narrower), longer stylet (11���13 vs 9.5���10.0 ��m), more posterior vulva (V = 66.0���69.5 vs 63���66) and lacks vulval dikes (vs having dikes 3 annuli long). Compared to M. neosulcus Geraert & Raski, 1986, its sister taxon in our SSU rDNA phylogeny, the new species has 3���4 head annuli (vs 5���6), lateral field with plain margins (vs slightly crenate), well-developed median bulb, valve, and valve plates (vs weakly developed), wider body annuli (2.1���2.3 vs 1.8���2.0 ��m), shorter tail (65���87 vs 86���96 ��m), with smaller c' (5.9���8.1 vs 8���10) and greater c (5.4���6.8 vs 4.7���5.5) values, and differences in SSU sequence (accession numbers KX907138 for the new species and KJ869330 for M. neosulcus). Compared to M. labiatus, its sister taxon in our LSU rDNA phylogeny, the new species has a longer stylet (11��� 13 vs 8���9 ��m), greater V value (66.0���69.5 vs 59���63), shorter tail (65���87 vs 98���112 ��m) and lacks both vulval flaps and a disc-like structure at the lip apex. Molecular Phylogeny. Partial sequencing of the SSU rDNA gene from the new species yielded a single fragment 1066 nt long. Blast searches using the sequence of this fragment revealed the highest coverage with two sequences of M. neosulcus (KJ869330) and M. acarayensis Andr��ssy, 1968 (KJ869331), with identities of 93% and 91%, respectively. A 98% identity was achieved for a short (74% coverage) sequence of M. pachycephalus. Two longer sequences (with 88% coverage) of M. pachycephalus (KX156286 and KX156286) had 92% identity with partial SSU rDNA of the new species. Lower identity and coverage percentages were returned for other sequences. A total of 98 species/isolates of Tylenchoidea ��rley, 1880, along with Aphelenchoididae Skarbilovich, 1947 and two panagrolaimid species as outgroup taxa were selected for our SSU rDNA-based phylogenetic analysis. This dataset comprises 1495 total characters, of which 739 are variable. Figure 4 presents the Bayesian phylogenetic tree inferred using this dataset. The major clade of Malenchus spp. in this tree (based on currently available SSU sequences for the genus, and designated M, in green) has full BPP and moderate (62%) ML BS support. The new species forms a well-supported clade (1.00 BPP / 98% MLBS) with M. neosulcus in this tree. The phylogenetic relationship of these two species (M. geraerti n. sp. and M. neosulcus) with M. acarayensis, M. pachycephalus and an unidentified isolate of Malenchus sp. (KX156289) is not further resolved due to polytomy. Partial sequencing of the LSU rDNA gene (D2/D3 region) from two females of the new species yielded single fragments of 650 (isolate1) and 654 (isolate 2) nt long. A Blast search using these fragments��� sequences indicated no significant identity with any of the currently available sequences deposited in GenBank. A total of 90 species/ isolates of Tylenchoidea (ingroup members) and Aphelenchoididae (as outgroup taxa) were selected for our LSU rDNA gene (D2/D3 region) phylogenetic analysis. This dataset contains 468 total characters, of which 297 are variable. Figure 5 presents the Bayesian tree inferred using this dataset. Species of the genus Malenchus occur in two major clades, A and B, in this tree. Clade A also includes the ambiguous species Filenchus balcarceanus Torres & Geraert, 1996 (sensu Qing et al. 2017), which shares characters of both Filenchus Andr��ssy, 1954 and Malenchus. The monophyly of this clade is highly supported (1.00 BPP / 81% MLBS). Clade B is a strongly supported (1.00 BPP / 99% MLBS) monophyletic group including our new, three known, and three unidentified isolates/species of Malenchus, along with two species of Lelenchus Andr��ssy, 1954. The new species clusters in a subclade containing two species of Lelenchus (KU234169, KP730042, KX156335) and M. labiatus (KP730047)., Published as part of Pedram, Majid, Soleymanzadeh, Mahya, Pourjam, Ebrahim & Mobasseri, Mahyar, 2018, Observations on MaleNChus geraerti n. sp. (Rhabditida: Tylenchidae), a morphological and molecular phylogenetic study, pp. 406-418 in Zootaxa 4369 (3) on pages 408-412, DOI: 10.11646/zootaxa.4369.3.6, http://zenodo.org/record/1135450, {"references":["Thorne, G. & Malek, R. B. (1968) Nematodes of the Northern Great Plains. Part I. Tylenchida (Nemata: Secernentea). South Dakota Agricultural Experiment Station Technical Bulletin 31, 111 pp.","Siddiqi, M. R. (1979) Seven new species in a new nematode subfamily Duosulciinae (Tylenchidae), with proposals for Duosulcius gen. n., Zanenchus gen. n. and Neomalenchus gen. n. Nematologica, 25, 215 - 236. https: // doi. org / 10.1163 / 187529279 X 00244","Andrassy, I. (1963) Freilebende Nematoden aus Angola, I. Einige moosbewohnende Nematoden. Publicacoes Culturais da Companhia de Diamantes de Angola, 66, 55 - 80.","Andrassy, I. (1968) Fauna Paraguayensis. 2. Nematoden aus den Galeriewaldern des Acaray Flusses. Opuscula Zoologica Budapestensis, 8, 167 - 315.","Andrassy, I. 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Data on five known species of the genus Coslenchus are provided. Morphological and morphometric data are given for all studied species. Three of the recovered species were also characterized by molecular phylogenetic data. The species C. leiocephalus was studied for the first time since its original description. Males of the species, C. franklinae and C. oligogyrus were described for the first time and the species C. oligogyrus was reported from Iran for the first time. In molecular phylogenetic studies based on partial sequences of 28S rDNA D2/D3 fragments, all species formed a clade with high Bayesian posterior probability in Bayesian inference, indicating the monophyly of the genus. The clade of Coslenchus spp. formed a highly supported monophyletic group, a sister clade to two species of the genus Aglenchus.