New nematode Tahamina indica gen. nov., sp. nov. (Nematoda, Dorylaimida, Tylencholaimoidea) from the tropical rainforest, Western Ghats Islam, Md Niraul Ahmad, Wasim ZooKeys 2023 2023-12-06 1186 1 13 https://zoobank.org/D76FB896-7ADD-4B6A-9529-3FE31353E335 Islam & Ahmad, 2023 Islam & Ahmad 2023 Enoplea Tylencholaimoidea Tahamina CoL Animalia Tahamina indica Dorylaimida 0 1 Nematoda species indica sp. nov.   Figs 1 , 2 , 3 , 4  Material examined.  Seven females and two juvenilesfrom Yaraganalu, Shivamoga District, Karnataka State, India;  13°48'04.3"N 75°34'23.4"E; 17 November 2018. Female  holotype(slide number AMUZDNC  Tahamina indicagen. nov. sp. nov. /1), six female  paratypespecimens (slide numbers AMUZDNC  Tahamina indicagen. nov. sp. nov. /2-5) and two juveniles(J2) (slide number AMUZDNC  Tahamina indicagen. nov. sp. nov. /6) are deposited with the nematode collection in the Department of Zoology, Aligarh Muslim University, India.  Measurements. See Table 1.   Table 1.Morphometrics of  Tahamina indicagen. n ov., sp. nov. All measurements are in μmand in the form: mean +/-SD (range).    Characters Holotype female Paratype females Juveniles  n 1 6 2  L 1413 1379.8 +/-34.9 (1332-1430) 1022, 1077  Body diameter at neck base 27 28.1 +/-0.68 (27-29) 21.5, 22.5  Body diameter at mid body 30 31 +/-0.48 (30-31) 21.5, 22.5  Body diameter at anus 16.5 17.3 +/-0.44 (16.5-17.5) 15.0, 15.5  a 46.5 43.8 +/-1.2 (43.1-46.7) 47.4, 47.8  b 5.2 5.01 +/-0.10 (4.9-5.2) 4.2, 4.4  c 15.3 15.2 +/-1.0 (13.7-17.0) 12.9, 13.7   c' 5.5 5.0 +/-0.42 (4.5-5.8) 5.4, 5.0  V 39.5 39.2 +/-1.1 (38.3-41.9) -  G1 4.9 3.1 +/-0.82 (2.4-3.4) -  G2 13.8 12.6 +/-0.90 (11.5-14.2) -  Lip region diameter 8.0 8.0 7.5, 7.0  Lip region height 4.0 3.7 +/-0.24 (3.5-4.0) 3.5, 3.0  Amphid aperture 5.0 4.4 +/-0.43 (4.0-5.0) 4.0, 4.0  Odontostyle length 8.5 8.4 +/-0.31 (8.0-9.0) 7.0, 6.5  Replacement odontostyle length - - 8.0, 7.5  Odontophore length 10.5 10.7 +/-0.31 (10.5-11.5) 11, 10.5  Total stylet length 19 19.1 +/-0.45 (19-20) 18, 17.5  Guiding ring from anterior 6.0 5.7 +/-0.18 (5.5-6.0) 5.5, 5.5  Nerve ring from anterior 93 93.2 +/-0.62 (92-94) 83, 90  Neck length 271 270.2 +/-4.9 (259-276) 243, 246  Expanded part of pharynx 127 125.8 +/-4.7 (115-131) 110, 115  Cardia length 6.0 6.4 +/-0.88 (5.0-7.0) 7.5, 6.0  Anterior genital branch 69 40.1 +/-4.4 (34-48) -  Posterior genital branch 195 178.7 +/-10.1 (168-195) -  Vaginal length 14.0 14.4 +/-0.44 (13.5-14.5) -  Vulva from anterior 558 553.5 +/-13.2 (539-579) -  Prerectum length 157 156.6 +/-13.0 (129-176) 121, 139  Rectum length 20.5 21.5 +/-1.2 (19-23) 18.5, 19.5  Tail length 92 89.3 +/-9.3 (79-103) 79, 78  Description.  Female. Slender nematodes of large sized, 1.3-1.4 mm long body, slightly curved ventrally upon fixation; body cylindrical, tapering gradually towards at the anterior end and posteriorly narrowing to form an elongated tail. Cuticle with two distinct layers, 1.0-1.5 μmthick at anterior region, 2.0-2.5 μmat midbody, and 3.0-4.0 μmon the tail. The outer cuticle is thin, with fine transverse striation, the inner layer is thicker than outer, distinctly striated. Lateral chord 5.0-7.0 μmat midbody, occupying about one-sixth to one-four (18-24%) of corresponding body diameter. Lateral, dorsal and ventral body pores are indistinct. Lip region cap-like, offset from the body by constriction, 2.0-2.2 times as wide as high or about one-fourth of the body diameter at the pharyngeal base. Under SEM (Fig. 3A), lips are rounded, and slightly separated, inner portion somewhat amalgamated forming a hexagonal disk-like structure, offset from the rest of the lip region; labial and cephalic papillae button-like, slightly protruding over the lip surface. Amphidial fovea cup-shaped, aperture slit-like, 4.0-5.0 μmwide or occupying about one-half to three-fifths of lip region diameter. Stoma a truncate cone. Odontostyle short, robust, spindle-shaped with a wide lumen, 1.0-1.1 times the lip region diameter long or 0.54-0.63% of total body length, it'saperture about one-fourth of the odontostyle length. Odontophore simple, rod-like with slightly thickened base or minute knobs-like structure (Fig. 1B, C), 1.2-1.4 times the odontostyle length. Guiding ring simple refractive, at 0.7-0.8 times lip region diameter from anterior end. Pharynx consisting of a slender and weakly muscular anterior part, expanding abruptly into a cylindroid bulb, separated by slight constriction, occupying about 42-49% of total pharyngeal length. Dorsal pharyngeal gland nuclei located at 12-16% of expanded part of pharynx from its expansion. Pharyngeal gland nuclei and their orifices are located as follows: DO=58-60, DN=60-62, DO-DN=1.5-2.5, S1N1=74-76, S1N2=79-81, S2N2=88-90, S2O=90-91. Nerve ring at 34-35% of the pharyngeal length from anterior end. Cardia is short, conoid, about one-fifth to one-fourth of the corresponding body diameter long.   Figure 1.  Tahamina indicagen. nov., sp. nov. female: Aentire B, Canterior region (arrow showing knobs-like structure) Danterior region showing amphid Epharyngeal region Fexpanded part of pharynx (arrow showing dorsal pharyngeal gland nuclei) Gpharyngo-intestinal junction. Scale bars: 100 µm( A); 10 µm( B-D, F-G); 20 µm( E).   Figure 2.  Tahamina indicagen. nov., sp. nov. female: Aentire Banterior region Canterior region showing amphid Dpharyngeal region Epharyngeal expansion Fgenital system GVulval region Hposterior end.   Figure 3.  Tahamina indicagen. nov., sp. nov. female (SEM): Aanterior region frontal view Banterior region lateral view C, Dposterior end showing anal opening. Scale bars: 1 µm( A); 2 µm( B); 10 µm( C, D).   Figure 4.  Tahamina indicagen. nov., sp. nov. female: A, Bgenital system C, Dvulval region Earrow showing genital primordia in juvenile Fposterior region Gposterior end. Scale bars: 20 µm( A, F); 10 µm( B-D, E-G). Genital system mono-opistho-ovarian, didelphic. Ovary reflexed, measuring 50-78 μmlong, not reaching oviduct-uterus junction; oocytes arranged in a single row except the near tip. Oviduct joining the ovary subterminally, measuring 57-82 μm, its consisting of a slender distal portion and a well-developed pars dilatata. Oviduct-uterus junction marked by the well-developed sphincter. Uterus long well differentiated, tripartite, proximal part short well-developed muscular, median part long, convoluted tube and distal part short, somewhat spheroid, measuring 96-109 μm. The anterior genital branch reduced to a simple sac, 34-69 μmor about 1.0-2.2 times midbody diameters long. Vagina cylindrical, extending inwards, 13.5-14.5 μmor about one-half (45-48%) midbody diameter; pars proximalis vaginae10-12 x6.0-8.0 μm, its wall encircled by circular muscles; pars distalis vaginae2.5-3.5 μmwith slightly curved walls; pars refringensabsent. Vulva pore-like. Sperm cell absent. Prerectum long, 7.3-10.0 and rectum 1.1-1.4 anal body diameter long. Tail elongated, tapering gradually and its distal part slightly bent dorsally with a rounded terminus, 4.3-5.8 times anal body diameter long with a pair of caudal pores on each side.  Male.Not found.  Juvenile (J2).General morphology is similar to that of adults, but with the following differences. Medium sized nematodes, 1.0 mm long. Lip region cap-like, 2.1-2.3 times as broad as high or about one-third (29-34%) of body diameter at the pharyngeal base. Functional odontostyle 0.90 times the lip region diameter long, 0.80 times the replacement odontostyle length. Replacement odontostyle 1.0 times the lip region diameter long, with its base located at 45-48 μmfrom the anterior end. Position of odontostyle forming cell nucleus at 48-49 μmfrom the anterior end and at 26-28 μmfrom the odontophore base. Odontophore simple, rod-like, 1.5-1.6 times of functional odontostyle length. Guiding ring simple and refractive, at 0.7 times the lip region diameter from the anterior end. Pharyngeal expansion occupying 45-46% of the total pharyngeal length. Nerve ring at 33-34% of the total pharyngeal length from anterior end. Genital primordia 18-19 µmor 0.8-0.9 times the corresponding body diameter long, located at 442-445 μmor 41-43% of body length from the anterior end.  Type habitat. Soil samples collected around the roots of grasses (  Cynodon dactylonL.) from Yaraganalu, Shivamoga District, Karnataka State, India.  Etymology. The new genus and new species named after first author mother's Tahaminaand its type locality India. 2023-01-01 2023-12-31 2023-01-01 India Yaraganalu Shivamoga District two 1 Karnataka State 2018-11-17 India 13.801194 Department of Zoology 1 75.573166 Aligarh Muslim University six 1 1 holotype