Paratylenchus undetermined

Rolish Singh, Phougeishangbam, Lokker, Bram, Couvreur, Marjolein, Bert, Wim & Karssen, Gerrit, 2022, Paratylenchus ilicis n. sp. (Nematoda: Paratylenchinae) Associated with Holly from the Netherlands and New Taxonomical and Phylogenetic Support for the Synonymization of Cacopaurus with Paratylenchus, Journal of Nematology 54 (1), pp. 1-14 : 3

PaRatyleNChUS iliCiS n. SP.

Figures 1–3 , Table 1

Description

Female

Body slender to obese, open C- to J-shaped or folded, obese light brown in color. Lateral field with four distinct lines, each line formed by rows of minute elements, extending from around midneck region to terminus, forming three bands; mid-band slightly wider than outer two bands. Lateral field enlarged into a characteristic oval to spindle-shaped structure around vulva level and demarcation of bands lost in this structure. Cuticle 2 Mm to 3 Mm thick; annuli ornamented by rows of minute refractive tubercles throughout body. Deirids visible in some specimens just around start of lateral field differentiation. Lip region conical-truncate to rarely rounded and continuous. EN FaCe roughly square-shaped with weak, non-protruding submedian lobes, and slit-like amphidial fovea on lateral sides of oral opening. Stylet thin and slender, variable in length from 70 Mm to almost 100 Mm, conus 80% to 90% of stylet length, with slightly posteriorly sloping transversely ovoid knobs. Pharynx often more than half of total body length in slightly obese individuals; median bulb pyriform with large sclerotized valves; isthmus slender and basal bulb rounded to oval, always smaller than median bulb. Secretory-excretory pore (SE pore) variable in position, depending on level of maturity and whether or not stylet is protruded (usually at half way from knobs to valve of median bulb in slightly obese individuals with non-protruded stylet); however, in markedly obese females, SE pore was difficult to observe. Hemizonid not observed. Reproductive system monodelphic with outstretched to sometimes reflexed ovary containing developing oocytes. Spermatheca rounded and filled with sperm cells. Vagina oblique and enlarges into a spacious thick-walled rounded uterine chamber. Vulval lips swelling both anteriorly and posteriorly, no vulva flaps, and vulva located at 89% to 95% of body length from anterior end. Post-uterine sac absent. Tail conical, often with an impression of immediate depression after swelling of posterior vulval lip. Anus obscure, very close to tail tip, 3 Mm to 5 Mm from tip. Tail terminus bluntly rounded.

Male

Body slender and slightly ventrally arcuate when heat relaxed. Cuticular ornamentation not seen. Lip region conical. Anterior part of body poorly developed without apparent stylet and pharynx. SE pore just above hemizonid. Deirids regularly observed near hemizonid level. Spicules ventrally arcuate, about 15 Mm; gubernaculum slightly arcuate, about 4 Mm in length. Narrow and thin bursa present, but can be easily overlooked. Cloacal sheath protruding. Tail region narrow, conical, and with finely rounded terminus.

Figures

Figure 1: Light and SEM images of PaRatyleNChUS iliCiS n. sp. paratype females. A: EN FaCe; B, C, F: Anterior regions showing cuticular ornamentation, stylet, pharynx, and SE pore position; D–E: Total body of (slightly) obese bodies showing major internal structures; G–M: Tail regions showing lateral field, vulva, and tail termini. SE pore: secretory-excretory pore; SEM: scanning electron microscopy.

Figure 2: Light and SEM images of PaRatyleNChUS iliCiS n. sp. paratype juveniles (J2) and males. A, E: eN FaCe of J2; B–D: Anterior regions showing stylet and pharynx of J2; F–I: Tail regions showing characteristic finger-like tip of J2; J: Total bodies of J2; K: Total bodies of males; L–M: Anterior regions of males showing absence of stylet; N–O: Tail regions showing spicules. SEM: scanning electron microscopy.

Figure 3: Line illustrations of PaRatyleNChUS iliCiS n. sp. paratypes. A, B, D: Total bodies showing developmental stages from juvenile (J2) to slightly obese to fully obese females; C: Anterior region of female showing stylet, pharynx, and SE pore position; E–G: Tail regions showing vulva, lateral field differentiation, tail shape, and tips of females; H: Tails of J2; I: Anterior region of J2; J: Anterior region of male; K: Posterior region of male. SE pore: secretory-excretory pore.