Search

Trichotylenchus disperses (Siddiqi & Sharma, 1995) Geraert, 2011 Figs. 1–2, Published as part of Chen, Yan, Han, Yu-Chun, Wang, Hui-Zhong, Xie, Hui & Xu, Chun-Ling, 2023, Redescription and Molecular Characterization of Trichotylenchus dispersus (Nematoda: Dolichodoridae) in China, pp. 552-566 in Zootaxa 5231 (5) on page 553, DOI: 10.11646/zootaxa.5231.5.4, http://zenodo.org/record/7609645, {"references":["Geraert, E. (2011) The Dolichodoridae of the world-Identification of the family Dolichodridae. Academia Press, Gent, 520 pp."]}

Wu, Wen-Jia, Yu, Lu, Xu, Chun-Ling, Wang, Dong-Wei, Xie, Hui (2018): A new species of the genus Eudorylaimus Andrássy, 1959 (Nematoda: Dorylaimida: Qudsianematidae) associated with Picea crassifolia in China. Zootaxa 4526 (4): 576-588, DOI: https://doi.org/10.11646/zootaxa.4526.4.9

Eudorylaimus piceae n. sp. Fig 1–2. Measurements. See Table 1. Material examined. Holotype ♀, from rhizosphere soil of Picea crassifolia at Helan Mountain, Alxa Left Banner, Alxa League, Inner Mongolia, China; GPS coordinates 105°51.500’ E, 38°39.717’ N; collected in August, 2014 by Lu Yu, Dong-Wei Wang, Wen-Jia Wu, and Hui Xie. Holotype and six female paratype specimens are deposited in the Lab of Plant Nematology / Research Center of Nematodes of Plant Quarantine, South China Agricultural University, Guangzhou, Guangdong 510642, China (slide numbers: M41-A, M41-B, M41-C and M41-D). Description. Female (Fig.1–2). Body robust, curved ventrally and presenting an open ‘C’ shape after fixation. Cuticle two layers, 3.5–5.0 µm thick in anterior region, 3.5–4.5 µm at mid-body, and 5.5–7.5 µm on tail; outer layer smooth with fine transverse striations, the inner one with radial ridges. Lateral chord occupying about one-fifth of the body diameter at mid-body. Lateral body pores indistinct. Ventral body pores distinct, 14–16 in the neck region, 5–10 between neck base to vulva and 8–10 between vulva and anus; dorsal body pores only seen in the anterior region, 4–8 in the neck region. Lip region clearly offset from the body by a constriction, 2.4–3.1 times as wide as high or 27%–29.5% of the body diameter at posterior end of the neck region. Lips separated, labial and cephalic papillae protruding. Amphidial foveae cup-shaped, aperture about one-third of the lip region diameter. Odontostyle 1.1–1.4 times the lip region diameter in length, aperture about one-third of odonstostyle length. Odontophore rodlike, 1.1–1.2 times as long as the odontostyle. Guiding ring single. Nerve ring located at 34%–42% of the total neck length. Anterior part of pharynx wide and expanding gradually, basal expansion occupying 42%–50.5% of the total neck length. Locations of the pharyngeal gland nuclei as follows: D = 63%–66%, AS 1 = 14%–24%, AS 2 = 32.5%– 43%, PS1 = 59%–70%, PS2 = 72%–82%. Cardia short, conoid to rounded. Genital system didelphic-amphidelphic. Ovaries reflexed, usually not reaching the junction of oviduct and uterus, anterior one 57–85 µm and posterior one 44–66.5 µm long. Oviducts consisting of a much wider pars dilatata and a slender part, anterior one 68–84 µm and the posterior one 66–86.5 µm long. Sphincter distinct, present at the junction of oviduct and uterus. Uteri simple with wide lumen, anterior 42.5–64 µm and posterior 44–58.5 µm long. Vulva transverse. Vagina extending inwards 32%–43% of the body diameter at vulva. Pars proximalis vaginae with straight walls, 13–20 µm long and 13–17 µm wide, pars refringens vaginae with two trapezoidal sclerotizations, each measuring 3–3.5 µm long and 4–6 µm wide, pars distalis vaginae appears weakly sclerotized, 2.5–4 µm long with curved wall. Prerectum length 2.3–3.3 times and rectum length 1–1.6 times the anal body diameter. Tail conoid with rounded terminus, bent ventrally. Male. Unknown. All soil samples were processed, but no males were found. Habitat and type locality. Rhizosphere soil of Picea crassifolia Kom. at Helan Mountain, Alxa Left Banner, Alxa League, Inner Mongolia, China. Etymology. The new species is named after Picea crassifolia, with which the new species is associated and which is also one of the endemic plants of China. Diagnosis and relationships. Eudorylaimus piceae n. sp. is characterized by having a body length of 1.03– 1.27 mm; lip region distinctly offset from the body; odontostyle 20–22 µm and 1.1–1.4 times the lip region diameter long; amphid aperture 5–6.5 µm; odontophore 1.1–1.2 times the odontostyle long; basal expansion of pharynx occupying 42%–50.5% of the total neck length; genital system didelphic-amphidelphic; vulva transverse; vagina extending inwards 32%–43%; average V value greater than 60; pars refringens vaginae with two trapezoidal sclerotizations and pars distalis vaginae appearing weakly sclerotized; prerectum 72–107 µm long, 2.3–3.3 times the anal body diameter in length, and rectum length 1–1.6 times the anal body diameter; tail conoid, bent ventrally; c’ value 1.5–1.8; males unknown. The new species can be differentiated from all other species of Eudorylaimus due to the development of the pars distalis vaginae, which appears weakly sclerotized (vs absent, or not sclerotized when present). In having body length less than 1.5 mm, amphidial foveae not quadrangular, tail curved ventrally and terminus rounded, c’ value less than 2 and b value less than 4.5 (Andrássy 1986, 1991, 2009), Eudorylaimus piceae n. sp. is close to E. arcus (Thorne & Swanger, 1936) Andrássy, 1959, E. brevis (Altherr, 1952) Andrássy, 1959, E. meridionalis Tjepkema, Ferris & Ferris, 1971, E. minutus (Bütschli, 1873) Andrássy, 1959, E. opistohystera (Altherr, 1953) Andrássy, 1959 and E. subdigitalis Tjepkema, Ferris & Ferris, 1971. Comparisons of the main characteristics differentiating the new species from these similar species are provided in Table 1. The new species comes close to E. opistohystera in having an average V value more than 60 (Andrássy 1986, 1991, 2009), but can be differentiated by having narrower amphid aperture (5–6.5 µm vs 10 µm; Tjepkema et al. 1971), longer odontostyle and shorter odontophore (20–22 µm vs 18–20 µm, 22–25 µm vs 25–30 µm, respectively; Altherr 1953), vagina extending inwards 32%–43% (vs nearly 50%; Altherr 1953), pars refringens vaginae with trapezoidal (vs rectangular; Tjepkema et al. 1971) sclerotizations, and male unknown (vs present; Altherr 1953, Tjepkema et al. 1971). From E. subdigitalis, the new species can be differentiated by its rounded tail terminus (vs subdigitate; Tjepkema et al.1971), amphid aperture narrower (5–6.5 µm vs 8–10 µm; Tjepkema et al. 1971), odontostyle longer (20–22 µm vs 15–18 µm, Tjepkema et al. 1971; Thorne 1974), vagina extending inwards 32%–43% (vs about 70%, see Fig. 4 in Moslehi et al. 2012), tail longer (46–59 µm vs 31–45 µm; Tjepkema et al 1971, or 36.5–43 µm; Moslehi et al. 2012) and prerectum longer (72–107 µm vs 60 µm, Tjepkema et al. 1971). From the other four species, the new species can be distinguished by having a longer odontostyle (20–22 µm vs less than 17 µm) and V value on average more (vs less) than 60. The new species also differs from E. arcus by having much larger c’ value (1.5–1.8 vs about 1; Thorne 1974, Thorne & Swanger 1936), vulva transverse (vs longitudinal; Thorne 1974), pars refringens vaginae trapezoidal (vs absent; see Fig. 15 in Thorne 1974) and males unknown (vs present; Thorne 1974, Andrássy 1986, Thorne & Swanger 1936). The new species differs from E. brevis (see data provided by online database: https://nematode.unl.edu/eudobre.htm) in having pars refringens vaginae trapezoidal (vs triangular), prerectum longer (72–107 µm vs 50 µm) and tail conoid (vs arcuate-conical). From E. meridionalis (see data provided by online database: https://nematode.unl.edu/eumerid.htm), the new species can be differentiated by having pars refringens vaginae trapezoidal (vs rectangular or somewhat triangular). Finally, from E. minutus, the new species differs by having tail conoid and bent ventrally (vs tail subdigitate) (Peña-Santiago & Ciobanu 2008). ……continued on the next page Molecular characterization and phylogenetic analysis. Sequences of 18S rDNA and the D2-D3 region of 28S rDNA of Eudorylaimus piceae n. sp. were obtained. Inter-individual variability was observed only in 18S rDNA, and the variation was 1 bp. Two sequences for 18S rDNA (1743 bp) obtained from two clones of one nematode, and one sequence for 28S rDNA (827 bp) were deposited in GenBank (accession numbers: KY942067 and KY942068 for 18S rDNA, KY942069 for 28S rDNA). In BLAST searches using the two 18S rDNA sequences, both showed the highest similarity (99%) to the sequence of an unidentified species of the genus Allodorylaimus (AJ966472) with 1 gap and 5 to 6 nucleotide differences. For the D2-D3 region of 28S rDNA, the highest similarity (94%) occurred with a sequence of E. minutus (AY593048) with 11 gaps and 38 nucleotide differences. In the 18S rDNA Bayesian trees (Fig.3), the sequences of the new species clustered with other sequences of Eudorylaimus spp., including E. minutus, in a single unresolved clade with 76% support. In the D2- D3 region of 28S rDNA Bayesian trees (Fig.4), the sequence of Eudorylaimus piceae n. sp. clustered with two sequences of E. minutus with 100% support.

Discolaimus anemaqen n. sp. Figs 1���3. Measurements. See Table 1. Material examined. Holotype, ♀, from soil around the roots of grasses from Graham Beach, Maqen, Guoluo Prefecture, Qinghai Province, China; GPS coordinate 100��12���36.3��� E, 34��28���03.2��� N; collected by Lin Yan and Sheng-Ying Jin in 2013. Holotype and seven female paratype specimens are deposited in the Lab of Plant Nematology/Research Center of Nematodes of Plant Quarantine, South China Agricultural University, Guangzhou, Guangdong 510642, China (slide numbers: 10���1. A and 10���1. B). Description. Female (Figs 1���3). Body slightly curved ventrad upon fixation. Cuticle two-layered, 2���3 ��m thick at mid-body and 4���6 ��m on tail; outer layer thin and with fine transverse striations throughout the body, inner layer thicker than the outer and distinctly thickened at the caudal region. Lateral chord 11���14.5 ��m wide or about one-fifth to one-fourth of the body diameter at mid-body, with 86 (82���90) lateral gland bodies on each side, 19���23 occurring in the neck region, 17���22 in the region from pharynx base to vulva, 40���46 in the region from vulva to anus, and 1���2 in the caudal region. Lip region offset by a distinct constriction, 0.4���0.6 times as wide as body diameter at pharyngeal base. With SEM, lip region seen to be disc-like, with six labial sectors separated by six Yshaped radial grooves which bifurcated before reaching the outer margin of lip region, and divided into six labial and six interlabial lobes by twelve longitudinal grooves. Amphid fovea an inverted-stirrup shape; aperture diameter about 0.3 times width at lip region. Odontostyle straight, strongly sclerotised with distinct lumen and opening, length 0.7���0.8 times the lip region diameter, its aperture 53���59% of its length. Odontophore rod-like, 1.7���2.0 times the odontostyle length. Guiding ring single. Nerve ring situated at 29���33% of neck length. Anterior part of pharynx muscular, with a swelling surrounding the base of odontophore, followed by another swelling then distinctly narrowing to about half its width at level anterior to the nerve ring until the anterior end of basal expanded part of pharynx, basal part of pharynx expanded gradually, 55���59% of the total neck length, with a sheath of tissue visible ventrally and at the base. Pharyngeal gland nuclei locations (Andr��ssy, 1998) as follows: D = 52���57%, AS1 = 42��� 54%, AS2 = 53���62%, PS1 = 73.5���83%, PS2 = 78���82%. Cardia conoid, no groups of large cells observed in cardiac region. Genital system amphidelphic. Ovaries reflexed nearly to vulva, anterior 79���130 ��m and posterior 65���152 ��m long. Oocytes arranged in a single row, except near germinal cell where two or more rows are present. Oviducts straight, broad; anterior 46���99 ��m and posterior 61���114 ��m long. Sphincter present at junction of oviduct and uterus. Uteri tubular; short in absence of eggs, anterior 31���38.5 ��m and posterior 32���53 ��m long; with eggs anterior 88���169 ��m and posterior 93.5���168 ��m long. No spermatozoa observed in genital system. Vulva a transverse slit, measuring 9 ��m in width. Vagina extending inwards about one-third of corresponding body diameter. Pars proximalis vaginae 10���13��12���15 ��m with convex walls; pars refringens lacking; pars distalis vaginae oblong, 3���5��6.5���7 ��m. Egg about 1.5���2 times as long as body diameter at mid-body, one to four eggs in a single female. Prerectum without prerectal sac, prerectum 0.7���1.0 times and rectum 0.8���1.0 times the anal body diameter. Tail short, dorsally convex, conoid, with flat ventral side and bluntly rounded terminus. Male. Not found. Type locality and habitat. Soil around the roots of grasses growing on Graham Beach, Maqen, Guoluo Prefecture, Qinghai Province, China. Etymology. The new species is named after the Animaqing Snow Mountain Legend, which is a part of China���s cultural heritage, and the mountain Anemaqen, which is located in Maqen, Guoluo Prefecture. Diagnosis and relationships. Discolaimus anemaqen n. sp. is characterized by having a body length of 1.92��� 2.15 mm; a disc-like lip region with six labial sectors separated by six Y-shaped radial grooves; amphid fovea an inverted-stirrup shape; strongly sclerotised odontostyle 0.7���0.8 times the lip region diameter in length, aperture 53���59% of its length; anterior part of pharynx with two swellings and distinctly narrowed from anterior to the nerve ring to the basal expanded part of the pharynx, basal part expanded with a sheath of tissue visible ventrally and at the base, occupying 55���59% of the total neck length; no groups of large cells in the cardiac region; female genital system amphidelphic; tail short (c��� = 1.1���1.3), dorsally convex conoid with straight ventral side and bluntly rounded terminus. Males were not found, and are either rare or absent. Based on the morphological measurements provided by Nasira et al. (2008), the new species is close to D. major Thorne, 1939, D. similis Thorne, 1939 and D. silvicolus Sauer & Annells, 1985 in the length of body and odontostyle. It differs from D. major by having a different surface on the lips (with six labial sectors separated by six Y-shaped radial grooves vs with six wedge shaped sectors, after Sauer & Annells 1985; basal part of the pharynx with a sheath of tissue visible ventrally and at the base (vs with an irregular sheath visible both dorsally and ventrally and at the base, after Sauer & Annells 1985) and lacking a prerectal sac (vs present, after Sauer &Annells 1985). From D. similis, it differs by having the basal part of the pharynx expanding gradually (vs abruptly, after Loof 1964); a different tail shape (dorsally convex, conoid with flat ventral side and bluntly rounded terminus vs regularly conoid with rounded tip, after Loof 1964); ovary with a large reflex reaching almost to the vulva (vs one-quarter to one-half, after Loof 1964; two-thirds the distance back to the vulva, after Thorne 1939) and relatively shorter eggs (1.5���2 times vs 3���4 times as long as body diameter at mid-body, after Thorne 1939). It differs from D. silvicolus (Sauer & Annells 1985) by having a larger body size (L = 1.92���2.15 mm vs L = 1.61��� 1.89); lower V value (V = 46.3���49.0 vs 51���53); anterior part of the pharynx with a swelling surrounding the base of the odontophore and followed by another swelling (vs without the second swelling); basal part of pharynx with a sheath of tissue visible ventrally and at the base (vs with a thick irregular sheath visible on both ventrally and dorsally and at the base) and no large cells observed in the cardiac region (vs a group of large cells with usually prominent nucleoli present posterior to the cardiac region). The new species differs from D. albarossicus Merzheevskaya1951, D. curvus Siddiqi 2005, D. krugeri Furstenberg & Heyns 1965, D. magnistylus Siddiqi 2005, D. mariae Pe��a-Santiago, Torres, Li��banas & Abolafia 2002 and D. pakistanense Nasira, Shahina & Erum 2008 by having a body length less than 2.2 mm. It also differs from D. bicorticus Furstenberg & Heyns 1965, D. constrictus Heyns 2001, D. levinae Furstenberg & Heyns 1965, D. neomajor Siddiqi 2005, D. papillatus Khan, Ahmad & Jairajpuri 1994, D. perplexans Siddiqi 1964 and D. trapezoides Siddiqi 2005 by having differing odontostyle lengths although similar body lengths. It is differentiated from the remaining species of Discolaimus by having a body longer than 1.8 mm., Published as part of Wu, Wen-Jia, Yan, Lin, Xu, Chun-Ling, Wang, Ke, Jin, Sheng-Ying & Xie, Hui, 2016, A new species of the genus Discolaimus Cobb, 1913 (Nematoda: Dorylaimida: Qudsianematidae) from Qinghai, China, pp. 129-138 in Zootaxa 4088 (1) on pages 130-134, DOI: 10.11646/zootaxa.4088.1.6, http://zenodo.org/record/399505

Wu, Wen-Jia, Yan, Lin, Xu, Chun-Ling, Wang, Ke, Jin, Sheng-Ying, Xie, Hui (2016): A new species of the genus Discolaimus Cobb, 1913 (Nematoda: Dorylaimida: Qudsianematidae) from Qinghai, China. Zootaxa 4088 (1): 129-138, DOI: 10.11646/zootaxa.4088.1.6