taxonID	type	description	language	source
4E2A87850D33FFF3FF39FA8CFEA3FE6C.taxon	description	(Figs 2 – 3) Material examined: Seven females from South Africa, in a good state of preservation. Measurements: See Table 1. Female: Slender nematodes of medium size, 800 - 935 μm long. Habitus after fixation often open-C shaped, in some specimens straight with inward bend and J-shaped. Body cylindrical, slightly tapering towards anterior end; the caudal region is rounded, sometimes with slight dorsal concavity. Cuticle 2 – 3 µm thick at midbody, with very fine transverse striation, annuli 0.3 – 0.5 µm wide. Lateral chords 4.4 – 5.7 µm wide or occupying about one-fourth (15 - 21 %) of mid-body diameter. Lateral pores distinct, 4 – 5 at neck region, 5 - 6 between cardia and vulva, and 5 – 6 between vulva and the tail tip. Lip region cap-like, offset from the body by a deep constriction; labial sclerotization absent. Under SEM, lip region triangular with straight sides and oral field perceptibly sunken (sucker-like); papillae round, and located at the middle of the base margins of lip region and weakly protruding on surface of lips. Lip region bearing six lips, slightly separated, and having six inner labial sensilla. Labial and cephalic sensilla visible under the SEM. Lip region 1.8 – 2.5 times as broad as high, and about 25 – 39 % of body diameter at neck base. Amphid fovea funnel-shaped, opening at level of the cephalic depression; its aperture 2.5 – 3.7 µm wide or about one-half (32 – 45 %) of lip region diameter. Odontostyle weak, 5.7 – 8.6 µm long, 0.6 – 1.1 times the lip region diameter long, and 0.7 – 0.9 % of total body length; aperture occupying about 8 – 16 % of total stylet length. Odontophore rod-like with small basal knobs, 1.2 – 1.4 times as long as the odontostyle. Guiding ring weakly developed and inconspicuous. Anterior slender part of the pharynx expanding very gradually; basal expansion 85 – 119 µm long, 2.7 – 4.4 times as long as body diameter at neck base. Pharyngeal gland nuclei and their orifices are located as follows: DN = 53 – 64 (n = 3, females), S 2 N = 88 (n = 1, female); the rest of nucleus and their orifice not visible because of thick musculature. Cardia short, conoid, 7.6 – 12.0 μm long, occupying about 20 – 30 % of corresponding body diameter. Genital system mono-prodelphic. Anterior genital branch well developed, represented by simple uterus, measuring 51 - 77 µm, or 1.6 - 2.9 times the mid-body diameter, and occupying about 5 - 9 % of total body length; ovary reflexed, 64 - 105 µm or 2.2 - 4.0 times the mid-body diameter long; oviduct-uterus junction indistinct; oviduct joining ovary subterminally, measuring 56 - 73 µm. Posterior branch represented by a small post-uterine sac, 8.7 - 17.0 µm long, 0.3 - 0.6 times the corresponding body diameter long. Vulva wide, transverse opening. Vagina straight, extending inwards, 35 - 50 % of the corresponding body diameter; pars proximalis vaginae almost as wide as long (6.9 - 8.2 × 7.5 - 9.6 µm), with convex walls; pars refringens vaginae absent; pars distalis vaginae 3 - 4 µm long with rounded walls. Prerectum 6.0 - 10.0 and rectum 0.8 - 1.3 times the anal body diameter long. Caudal pores pair, one visible under the SEM on the lateral side of the tail. Male: not found for both the South African and Indian populations of T. mirabilis. Morphometric comparison of the South African and Indian populations of T. mirabilis The current measurements (Table 1) and Figures 2 & 3 (South African) and Figure 4 (Indian) populations of T. mirabilis exhibited several consistent morphometric differences that support their separation in the discriminant and hierarchical analyses. South African specimens generally showed higher a and c values, indicating a slenderer body and slightly shorter tail relative to body length, whereas Indian specimens displayed lower a and c′ values reflecting a comparatively stouter habitus and a comparatively shorter tail. The b ratio was highest in the Indian shrub – litter population, suggesting a relatively shorter pharynx in this group. The V value also differed subtly but consistently, with the vulva located slightly more posteriorly in the Indian population (up to 62.2 %) than in the South African specimens (approximately 60 – 62 %). One of the separating characters was the posterior genital branch, which was distinctly longer in the South African populations (4 – 17 μm) but consistently shorter in the Indian population (6 – 9 μm). Additionally, odontostyle length tended to be greater in the South African specimens (6 – 9 μm) compared with the Indian population (6.5 – 7.5 μm). Tail length showed a similar pattern, with Indian specimens — particularly the shrub – litter population — exhibiting slightly shorter tails on average. Collectively, these aligned differences in body ratios, reproductive structures, tail morphology, and stylet length provide morphological support for the multivariate separation of the South African and Indian populations. All South African specimens were in good condition. They were similar to the materials collected from the kiwi farm; however, there were slight differences in their body length, as shown in Table 1. In addition, the South African populations of T. mirabilis were compared with the previously studied ones from Germany (Loof and Jairajpuri, 1968; Thorne, 1939), Spain (Peña-Santiago and Coomans, 1994), India (Islam and Ahmad, 2021), and Italy (Vinciguerra, 1986). All populations from various locations showed the same morphometric features. However, the South African populations showed a longer posterior genital branch compared with Germany (4 - 14 vs 4 µm; see Loof and Jairajpuri, 1968). The rest of the measured characters overlap and showed no significant differences.	en	Shokoohi, Ebrahim, Ahmad, Wasim, Islam, M. Niraul, Masoko, Peter (2026): Geographical variation in Tylencholaimus mirabilis (Nematoda: Tylencholaiminae) evidence from South African and Indian populations. Zootaxa 5831 (3): 381-398, DOI: 10.11646/zootaxa.5831.3.4, URL: https://doi.org/10.11646/zootaxa.5831.3.4
