196,539 research outputs found
Metarhabditis andrassyana Tahseen 2004
No full text<i>Metarhabditis andrassyana</i> Tahseen et al., 2004 <p>(Figures 3 and 4)</p> <i>Measurements</i> <p>See Table 1.</p> <i>Description</i> <p> <i>Female.</i> Body straight or slightly arcuate, tapering at both extremities, more towards posterior end. Cuticle with both outer and inner layers striated. Longitudinal striae moderately to faintly developed. Lateral lines three in few specimens splitting into five to six in posterior body region. Lip region almost continuous to adjoining body. Lips round, in doublets forming three sectors (one subdorsal and two subventral). Amphids inconspicuous. Stoma rhabditoid type, long, narrow, 1.8–3.0 times the lip diameter in length. Cheilostom conspicuous, moderately cuticularized; gymnostom smaller than stegostom. Pharyngeal collar surrounding 55–60% of stoma. Metastegostom isomorphic and isotopic with each plate bearing four to six denticles having knobbed heads. Telostegostom isoglottoid. Pharynx differentiated into 120–143 µm long, cylindrical, weakly developed corpus, slightly narrower, 59–70 µm long isthmus and a round, basal bulb of 28–32 × 23–26 µm dimension with a prominent grinder and faintly double-chambered haustrulum. Nerve ring at 66–78% of pharyngeal length. Secretory–excretory pore slightly anterior to basal bulb or 75–81% of pharyngeal length with distally cuticularized duct. Hemizonid usually observed anterior to secretory–excretory pore. Pharyngeal corpus <i>ca</i>.1.3–1.7 times longer than isthmus and basal bulb together. Body at pharyngeal end 2.9–5.4 times the labial diameter in length. Cardial flaps conoid, 5–7 µm long. Intestine with refractive lumen lining. Rectum slightly longer than anal body diameter with dilated lumen; three conspicuous rectal glands present. Prerectum markedly differentiated in few specimens only. Reproductive system didelphic, amphidelphic with well-developed, dorsally reflexed ovaries. Anterior ovary on right and posterior on left side of intestine. Oviduct leading to offset, ovoid spermathecae containing rounded sperm, demarcated from uterus by distinct sphincters. Two to fifty intrauterine eggs observed in different stages of embryonation. Vagina thick-walled, at right angle to longitudinal body axis, about one-third of vulval body diameter in length. A pair of globular pieces associated with vagina reflect muscles in cross-section. Vulva a wide transverse slit, almost extending the full width of the body diameter at the level of the vulva, with an epiptygma and distinct cuticular flap. Tail long, filiform. Phasmids tubular, at base of conical part of tail or 28–36 µm posterior to anal level.</p> <p> <i>Male.</i> Similar to female in general morphology except in pronounced posterior body curvature. Testis single, reflexed ventrally on left side of intestine. Vas deferens a broad tube, filled with sperm without demarcation of seminal vesicle. Ejaculatory glands absent. Spicules long, robust having round capitula with attenuated ventral and distally notched dorsal arm. Spicule lenght 1.2–1.7 times the anal body diameter. Gubernaculum slightly curved plate with curved proximal end, 40–47% of spicule length. Bursa fairly developed, open leptoderan type, not enclosing small tail spike. Bursal margins often crenate. Tail spicate with fine terminus. Genital papillae eight pairs in 1 + 1/1 + 3 + 2 + P configuration. GP1, GP2 spaced, precloacal; GP3 shifted posterior to cloaca; out of other six postcloacal pairs – GP4, GP5 and GP6 closely placed; GP5, GP7 dorsally oriented; GP8 anterior to fine tubular phasmids. Copulatory muscles six-paired faintly visible bands extending anteriorly to spicules.</p> <p> (<i>Continued</i>)</p> <i>Habitat and locality</i> <p> Moist soil samples collected from a ditch with decaying matter at Sasni (Geographic coordinates 27 ◦ 51 l 42.78 ll N, 78 ◦ 04 l 14.37 ll E), Aligarh, Uttar Pradesh, India.</p> <i>Voucher material</i> <p> Eight females and six males on slide <i>Metarhabditis andrassyana</i> NOS /1-7 deposited in the Nematode Collection, Department of Zoology, Aligarh Muslim University, Aligarh, Uttar Pradesh, India. One female and one male on slide <i>Metarhabditis andrassyana</i> NOS /8 deposited at the Laboratory of Nematology, Wageningen University and Research Center (WUR), 6700 ES Wageningen, the Netherlands.</p> <i>Remarks</i> <p> The present population conforms to <i>Metarhabditis andrassyana</i> Tahseen et al., 2004 in most morphometric and morphological characteristics. However, some minor differences can be noted: distinct (versus indistinct) lateral fields; faint (versus distinct) longitudinal striae; smaller (versus larger) and four to six (versus seven to eight) metastegostomal denticles on each plate; nearly undifferentiated (versus slightly differentiated) corpus; and a relatively posteriorly located GP3 (versus adcloacal position of GP3 reported in <i>Metarhabditis andrassyana</i> Tahseen et al., 2004). Another important feature observed is the conspicuously dilated though short rectum uniformly present in all specimens.</p>Published as part of <i>Asif, M., Prasad, J. S., Khan, R., Somasekhar, N. & Tahseen, Q., 2013, A revision of the genus Metarhabditis (Nematoda: Rhabditidae) with description of three known species, a key to the identification of congeners and discussion of their relationships, pp. 2599-2622 in Journal of Natural History 47 (41 - 42)</i> on pages 2605-2610, DOI: 10.1080/00222933.2013.798702, <a href="http://zenodo.org/record/5197855">http://zenodo.org/record/5197855</a>
Description of a new and a known insect-associated species of the genus Halicephalobus Timm, 1956 (Panagrolaimidae: Rhabditida) along with intrageneric relationship
No full textMahboob, M., Tahseen, Q. (2022): Description of a new and a known insect-associated species of the genus Halicephalobus Timm, 1956 (Panagrolaimidae: Rhabditida) along with intrageneric relationship. Journal of Natural History 55 (39-40): 2549-2567, DOI: 10.1080/00222933.2021.200635
First record of the leafhopper genus Xenovarta Viraktamath (Hemiptera, Cicadellidae, Deltocephalinae) from India with description of a new species
No full textMeshram, Naresh M., Hashmi, Tahseen Raza (2018): First record of the leafhopper genus Xenovarta Viraktamath (Hemiptera, Cicadellidae, Deltocephalinae) from India with description of a new species. Zootaxa 4532 (3): 444-446, DOI: 10.11646/zootaxa.4532.3.
Plectonchus longevulvus Khan & Hussain & Tahseen 2012, sp. nov.
No full text<i>Plectonchus longevulvus</i> sp. nov. <p>(Figures 5, 6)</p> <p> <i>Measurements</i></p> <p>See Table 2.</p> <p> <i>Description</i></p> <p> <i>Female.</i> Body small to medium-sized, ventrally curved upon fixation, tapering more towards posterior end. Cuticle distinctly loose, 2–5 µm thick, transversely striated, annuli 0.2–0.5 µm wide in different body regions. Longitudinal lines and lateral field indistinct. Lip region continuous with adjoining body contour. Labial sensilla papilliform. Amphids inconspicuous. Stoma 0.6–1.2 labial diameter long. Cheilostom indistinguishable. Gymnostom and stegostom fused to form weakly sclerotized funnelshaped chamber narrowing into pharyngeal lumen. Pharynx panagrolaimoid type comprising of 57–70 µm long, cylindrical corpus, narrower 35–38 µm long isthmus and ovoid basal bulb of 13–17 × 11–13 µm dimension with a grinder and single-chambered haustrulum. Nerve ring encircling isthmus at 60–76% of pharyngeal length, surrounding isthmus. Excretory pore located above nerve ring or at 44–57% of pharyngeal length at posterior level of pharyngeal corpus. Body at pharyngeal end 2.5–2.8 labial diameter wide. Cardia conoid, 2–4 µm long. Intestine granular with wide lumen. Rectum thin-walled, 1.4–1.7 anal body diameter long. Anus a crescentshaped opening. Female reproductive system monodelphic, prodelphic. Ovary dorsally reflexed at right side of intestine with distal end not reaching vulva. Oocytes arranged in two rows in germinal zone but in single row beyond that. Spermatheca distinctly offset, oval, filled with sperms. Vagina anteriorly directed, about 1 / 2 of corresponding body diameter long. Ovoid glandular cells found associated with dorsal and ventral uterine walls. Usually one intra-uterine egg of 39 × 11 µm dimension present. Postuterine sac absent. Vulva–anus distance 43–68 µm or about 2.8–4.4 times anal body diameter. Tail elongate, conoid with pointed terminus. Phasmids located at middle of tail.</p> <p> <i>Male.</i> Similar to female in general morphology but smaller in size with pronounced posterior curvature. Testis monorchic, ventrolaterally reflexed, on the right of intestine; occasionally outstretched distally. Vas deferens narrowing into ejaculatory duct. Spicules stout, slightly ventrally curved with round capitula and beak-like distal ends, 1.0–1.4 anal body diam. long. Gubernaculum lancet-shaped, proximally hooked, 0.7–0.9 times spicule length. Bursa absent. Caudal papillae seven pairs: two precloacal and five postcloacal pairs in 1+1 <i>/</i> 1+P+1+2+1 configuration. GP1 and GP2 ventrolateral, GP1 located at about 1.3–1.5 spicule length from cloacal opening; GP2 at middle level of spicules; GP3 ventrolateral located at about half of cloacal body diam. form cloacal opening; GP4 subdorsal; GP5 and GP6 subventral, closely placed, located at end of conoid part of tail; GP7 laterodorsal, slightly posterior to end of conoid part of tail. Phasmid located between GP3 and GP4. Tail conoid tapering to a narrow pointed terminus.</p> <p> <i>Diagnosis</i></p> <p> <i>Plectonchus longevulvus</i> sp. nov. is characterized by thick cuticle; indistinct lateral field; weakly sclerotized funnel-shaped stoma; cylindrical pharyngeal corpus gradually narrowing into isthmus; posterior vulva; presence of ovoid glandular cells associated with dorsal and ventral uterine walls; spicules having prominent capitula and beak-like distal ends; lancet-shaped, proximally hooked gubernaculum and seven pairs of caudal papillae in 1+1 <i>/</i> 1+P+1+2+1 configuration.</p> <p> <i>Differential diagnosis and relationships</i></p> <p> The new species most closely resembles <i>P. molgos</i> Massey, 1974 but differs in having smaller b and greater V values, papilliform labial sensilla, presence of glandular cells found associated with dorsal and ventral uterine walls, greater number of postcloacal papillae and tail with a terminal spike (versus b = 5.1–5.6, V = 75, labial sensilla setiform, absence of ovoid glandular cells, four pairs of post-cloacal papillae and finger-like peg in tail reported in <i>P. molgos</i>).</p> <p> The new species differs from <i>P. ateri</i> Fuchs, 1930 in having smaller b and greater V values, smaller stoma, smaller tail and greater number of genital papillae (versus b = 6, V = 73.7, stoma = 10 µm long, tail = 78 µm long and six pairs of genital papillae present in <i>P. ateri</i>).</p> <p> <i>Plectonchus longevulvus</i> sp. nov. also differs from <i>P. extrematus</i> Gunhold, 1952 in having smaller females, smaller a and greater c values, presence of ovoid glandular cells associated with dorsal and ventral uterine walls and larger gubernaculum (versus L = 0.75–0.90 mm, a = 32–34, c = 8–9, absences of ovoid glandular cells and gubernaculum is 11–12 µm long in <i>P. extrematus</i>).</p> <p> The new species differs from <i>P. wyganti</i> Massey, 1964 in having smaller females, smaller c′ and greater V values, loose cuticle, indistinct lateral field, narrower and weakly sclerotized stoma, presence of ovoid glandular cells associated with dorsal and ventral uterine walls, gubernaculum with pointed head and greater number of genital papillae (versus L = 0.7 mm, c′ = 5, V = 77, cuticle of normal thickness, lateral field two incisures, stoma = 5 µm wide and strongly sclerotized, absences of ovoid glandular cells, head of gubernaculum is rounded and six pairs of genital papillae in <i>P. wyganti</i>).</p> <p> <i>Type habitat and locality</i></p> <p> The sample containing <i>Plectonchus longevulvus</i> sp. nov. was collected from a ditch (alluvium soil) at Kishtwar, Jammu and Kashmir and Khair, Aligarh, Uttar Pradesh, India at 33 ◦ 19 ′ N, 75 ◦ 46 ′ E.</p> <p> <i>Type material</i></p> <p> Holotype female, 13 paratype females and 11 paratype males on slide <i>Plectonchus longevulvus</i> sp. nov. No. NOJ &K <i>/</i> 1-10 deposited in the Nematode Collection, Department of Zoology, Aligarh Muslim University, Aligarh, Uttar Pradesh, India. One female paratype and one male paratype on slide <i>P. longevulvus</i> sp. nov. No. NOJ &K <i>/</i> 11, deposited at the Laboratory of Nematology, Wageningen University and Research Center (WUR), 6700 ES Wageningen, the Netherlands.</p> <p> <i>Etymology</i></p> <p>The Latin epithet of the species (longe = far; vulvus = vulva) reflects the farthest location of vulva reaching up to 86% of the body length.</p>Published as part of <i>Khan, R., Hussain, A. & Tahseen, Q., 2012, Descriptions of one new and two known species of Panagrolaimoidea (Nematoda) from India, pp. 867-884 in Journal of Natural History 46 (13 - 14)</i> on pages 876-881, DOI: 10.1080/00222933.2011.653589, <a href="http://zenodo.org/record/5199708">http://zenodo.org/record/5199708</a>
Pelodera paratretzeli Mahboob & Jahan & Tahseen 2023, sp. nov.
No full text<i>Pelodera paratretzeli</i> sp. nov. <p>urn:lsid:zoobank.org:act: C4B7FC68-5CD4-4A07-8B72-E4B32459F209</p> <p>Figs 7–9, 13–15; Tables 3, 5–6; Appendices 1–2</p> Diagnosis <p> <i>Pelodera paratretzeli</i> sp. nov. is characterized by conspicuous sexual dimorphism in anterior region with females having lip region strongly offset with well-developed, globular lips and males having lip region dome-shaped, continuous, with low, amalgamated lips; stoma 2.5–3.8 times as long as wide; metastegostom anisomorphic with three well-developed setose denticles on each sector; vulval lips not protruded, flanked by cuticular flaps; tail cupola-shaped with a long spike; spicules with rounded capitulum, long neck, fused up to 12–14% of spicule length; bursa peloderan, anteriorly closed and punctated; anterior bursal rim distant from cloacal opening; bursal velum lobed with a shallow groove at cloaca; genital papillae nine pairs: three pre cloacal and six post cloacals arranged in 3/2+Ph+3+1 configuration. GP1-3 closely placed. GP3 shorter than others. GP4, GP5 and relatively shorter and thickened phasmid forming a group, quite posterior to cloaca; GP6–8 basally fused, equal in shape and size.</p> Etymology <p> The species epithet ‘ <i>paratretzeli</i> ’ indicates its close similarity with <i>P. tretzeli</i> (Sachs, 1950).</p> Material examined <p> <b>Holotype</b> INDIA • ♀; Uttar Pradesh, District Aligarh; 27°08′37.38″ N, 82°38′59.65″ E; 309 m a.s.l.; isolated from the elytra (front wing) of dung beetle, <i>Digitonthophagus bonasus</i> (Coleoptera: Scarabaeidae) (the beetle specimens were destroyed due to dissection/excision); AMU/ZD/NC slide no. <i>Pelodera paratretzeli</i> sp. nov. /HS/AL/ST/BS/1.</p> <p> <b>Paratypes</b> INDIA • 5 ♀♀, 5 ♂♂, 5 juvs; same collection data as for holotype; AMU/ZD/NC slide no. <i>Pelodera paratretzeli</i> sp. nov. /HS/AL/ST/BS/2–12.</p> Description <p> <b>Adult</b></p> <p>Body medium-sized, plump, almost straight, with tapering ends. Sexual dimorphism conspicuous in anterior region. Cuticle with transverse and longitudinal striations and fine punctations. Lip region strongly offset from body contour and dilated, ca 2.6–3.2 times as wide as high. Lips globular, distinctly separated, with slightly raised labial sensilla. Amphids labial with small, elliptical apertures. Stoma well-developed, 2.5–3.8 times as long as wide or 11–14% of total pharyngeal length. Cheilostom highly cuticularized. Gymnostom with parallel walls. Stegostom surrounded by pharyngeal tissue up to half of stoma length. Metastegostom anisomorphic and most widened part of stoma, armed with three prominent setose denticles on each plate. Telostegostom heavily cuticularized. Pharynx well-developed, divided into 58–68 μm long corpus, a well-developed, muscular, strongly swollen metacorpus of 18–28 ×20–26 μm; a relatively narrower, 40–53 μm long isthmus, and a well-developed basal bulb of 18–28 μm ×18–24 μm, with a grinder and cuticularized double-chambered haustrulum. Cardia conoid, 5–7 μm long. Nerve ring encircling anterior region of isthmus, just posterior to median bulb at 62.7– 67.1% of pharyngeal length. Secretory-excretory pore located posterior to nerve ring, at mid-level of isthmus or at 79.6–82.8% of total pharyngeal length from anterior end. Intestine showing a bacterial pouch just posterior to pharyngo-intestinal junction. In some individuals, an intestinal diverticulum representing shifted bacterial pouch was observed. Rectum, 0.5–0.7 times anal body diameter. Tail cupola-shaped, ca 1.5–1.7 times as long as anal body diameter. Spike covering more than half of total tail length. Phasmids opening at level of anus.</p> <p> <b>Female</b></p> <p>Reproductive system didelphic, amphidelphic, ovaries well-developed, opposed and dorsally reflexed, distal ends reaching up to vulva. A coelomocyte present close to distal tip of each ovary, while another found close to reflexed part. Oocytes with prominent nuclei arranged in multiple rows distally. Oviducts not distinctly separated. Spermathecae elongated, filled with sperm. Uteri spacious, accommodating two to ten eggs at a time. Vagina cuticularized, thick-walled. Vulva equatorial, a transverse slit, with lips not protruded. Lateral cuticular vulval flaps present.</p> <p> <b>Male</b></p> <p>Sexually dimorphic with lip region dome-shaped, continuous with body contour. Lips weak, amalgamated, without a discernible identity. Pharynx relatively weak with moderately swollen metacorpus. Anterior region of intestine showing a small bacterial pouch. Testis single, dorsally reflexed, on right lateral side of intestine. Spermatocytes arranged in multiple rows. Seminal vesicle filled with spermatocytes leading to vas deferens.A pair of well-developed ejaculatory glands present.A coelomocyte present close to distal end of testis while another found close to reflexed part. Tail conoid, ending in an acute terminus. Bursa well-developed, anteriorly closed, transversally and longitudinally striated with dot-like punctations. Bursal velum lobed with a shallow groove at cloaca. Anterior bursal rim distant from cloacal opening. Spicules almost straight, slender with rounded capitulum, narrow neck and shaft fused distally up to 12–14% of total length. Gubernaculum trough-shaped, ca 42.5–46.6% of spicule length. Genital papillae nine pairs, arranged in 3/2+Ph+3+1 configuration with pre cloacals GP1 and GP2 forming a group along with very short GP3, nearly half the length of others. GP1, GP4 and GP9 opening dorsally outside bursa; GP4, GP5 and phasmid forming a group; phasmids relatively shorter and thickened, located in between GP5 and group of GP6. GP6–8 basally fused, equal in shape and size. GP9 dorsally oriented.</p> <p> <b>Dauer/phoretic juvenile</b></p> <p>Body almost straight, abruptly tapering posterior to anus. Cuticle with fine transverse striations. Lateral field inconspicuous. Lip region continuous with amalgamated lips. Oral aperture covered with a cuticular plug. Stoma long, narrow, ca 5 times as long as wide. Metastegostomal swelling weakly developed, with faintly visible small denticles. Pharynx with a slender procorpus ca 40–52 μm long, an oblong, ca 12–13 μm×9–12 μm metacorpus, a narrow, ca 22–32 μm long isthmus and a pyriform, ca 14–17 μm ×10–14 μm basal bulb, lacking valvular plate. Nerve ring encircling mid-region of isthmus. Secretory-excretory duct inconspicuous. Rectum faintly visible, ca equal to anal body diameter. Phasmidial aperture inconspicuous. Tail long, conoid, covered with hyaline sheath and ended with a sharp, pointed tip.</p> Remarks <p> <i>Pelodera paratretzeli</i> sp. nov. comes close to <i>P. tretzeli</i> (Sachs, 1950) in most morphological characters but differs in females having small-sized body (644–866 μm vs 1543–3327 μm); smaller b (4.8–5.5 vs 8.1–11.9) and c (15.9–21.5 vs 28.4–33.1) values; metastegostom anisomorphic (vs isomorphic); rectum 0.5–0.7 times (vs 0.3–0.4 times) anal body diameter; phasmids at level of anus (vs at base of wider part of tail); males with smaller body length (483–639 μm vs 636–758 μm); smaller b (3.7–4.6 vs 4.9–5.9), c (17.2–21.3 vs 28.4–35.6) and greater c’ (1.2–1.5 vs 0.7–0.8) values; spicules slender (vs slightly plump), having distinct neck (vs neck not demarcated); bursa with shallow groove (vs deep indentation) laterally at level of cloaca; genital papillae with slender bases (vs swollen bases in <i>P. tretzeli</i> fide Sachs (1950)).</p>Published as part of <i>Mahboob, Mohammad, Jahan, Rehmat & Tahseen, Qudsia, 2023, Comparative and cladistic analyses of the species of the genus Pelodera Schneider, 1866 (Rhabditidae: Nematoda) belonging to the coarctata group, pp. 71-114 in European Journal of Taxonomy 890 (1)</i> on pages 87-93, DOI: 10.5852/ejt.2023.890.2253, <a href="http://zenodo.org/record/8283523">http://zenodo.org/record/8283523</a>
Pelodera indica Mahboob & Jahan & Tahseen 2023, sp. nov.
No full textPelodera indica sp. nov. urn:lsid:zoobank.org:act: AE90DC74-C667-4E6B-AE39-D400BF61F43A Figs 1–3, 13–15; Tables 1, 5–6; Appendices 1–2 Diagnosis The new species Pelodera indica sp. nov. is characterized by transversely and longitudinally striated cuticle; sexual dimorphism in anterior region with females having conspicuously expanded, offset lip region; lips distinctly separated with tapering ends directed towards oral aperture; laterals larger than submedians; stoma wide, having three strong setose denticles on each metastegostomal plate; secretory-excretory pore at level of basal bulb or cardia; distal end of ovaries reaching up to vulva, often crossing each other; bursa peloderan, anteriorly closed; velum punctated with two deep grooves on either side; genital papillae nine pairs, compactly placed arranged in 0/1+1+1+1+1+P+3+1 configuration; without any gap between pre- and post cloacals; GP1 anteriorly directed with base located at level of posterior cloacal lip; GP1, GP4 and GP9 opening dorsally; genital papillae GP6–8 basally fused. Etymology The species name is derived from the name of the country ‘India’. Material examined Holotype INDIA • ♂; Eastern Uttar Pradesh, Terai region, District Sidhharthnagar; 27°08′37.38″ N, 82°38′59.65″ E; 309 m a.s.l.; isolated from the elytra (front wing) of dung beetles Catharsius molossus (Coleoptera: Scarabaeidae) (the beetle specimens were destroyed due to dissection/excision); AMU/ZD/NC slide no. Pelodera indica sp. nov. /NIT/ctrs/1. Paratypes INDIA • 9 ♂♂, 9 ♀♀, 5 juvs; same collection data as for holotype; AMU/ZD/NC slide no. Pelodera indica sp. nov. /NIT/ctrs/2–15. Description Adult Body medium-sized, almost straight to slightly ventrally arcuate, tapering at both extremities. Cuticle 1 μm thick, finely annulated, with fine longitudinal lines and inconspicuous punctations. Lip region showing sexual dimorphism, with females having 2.5–3.0 times as wide as high, offset lip region more expanded than in males. Lips six, globular, distinctly separated with tapering ends projecting into stomal cavity; lateral lips larger than submedians. Labial sensilla papilliform. Amphids labial with small openings indiscernible under LM. Stoma well-developed, posteriorly widened, ca 3–4 times as long as wide or 13.1–13.4% of pharyngeal length. Cheilostom small, rod-shaped, cuticularized. Gymnostom with parallel walls, strongly cuticularized. Stegostom covering about 45–46% of stoma from its base. Metastegostom anisoglottoid, relatively widened with three strongly developed, thorn-like setose denticles on each plate. Telostegostom heavily cuticularized. Pharynx well-developed, highly muscular, divided into 65–70 μm long corpus with prominent metacorpal swelling, a slightly narrower 39–49 μm long isthmus, and a muscular, rounded to ovoid basal bulb of 26–31 μm×25–28 μm dimension with a well-developed grinder and two-chambered haustrulum. Nerve ring encircling posterior region of isthmus at ca 71–82% of pharyngeal length. Secretory-excretory duct opening at level of basal bulb, at ca 82.8–98.2% of pharyngeal length. Intestine with wide lumen, often dilated at anterior and posterior ends to form bacterial pouches with intestinal epithelium thinning out in the region; intestinal lumen refractive. Rectum 20–26 μm long, shorter than anal body diameter often with dilated lumen; rectal glands distinct. A thick-walled, conspicuous pre-rectal pouch observed in one specimen. Female Reproductive system didelphic, amphidelphic; ovaries paired, lateroventrally reflexed with distal parts often crossing each other. Oocytes with prominent nuclei, arranged in multiple rows around rachis towards distal end. Spermathecae filled with stacked spermatozoa. Each uterus divided into well-developed glandular and muscular parts; two pairs of glandular cells opening at proximal end of vagina. Intra-uterine eggs about 6–10, linearly arranged end to end or obliquely placed. Vagina thick-walled. Vulva transverse slit with protruded vulval lips. Tail cupola-shaped with a moderately developed spike of ca ½ of tail length. Phasmids opening laterally at level or just posterior to anus. Male Similar to female in general morphology except for relatively narrower lip region and body having greater ventral curvature posteriorly. Lip region narrow, continuous, or slightly offset from body contour. Lips relatively smaller than those of female, laterals larger than submedians. Testis single, dorsally or laterally reflexed, on right side of intestine. Spermatocytes arranged in multiple rows; seminal vesicle separated from vas deferens by a deep constriction. Tail conoid, tapering posteriorly to an acute terminus. Spicules with rounded capitulum, narrow neck and slender shaft, fused distally up to 24–28% of total length. Gubernaculum slender, trough-shaped, 37–51% of spicule length. Genital papillae nine pairs, evenly spaced and arranged in 0/1+1+1+1+1+P+3+1 configuration, without any gap in between. GP1 slender, directed towards anterior edge of bursa, with base located at posterior cloacal lip or beyond. GP2 relatively plump. GP1, GP4 and GP9 opening dorsally. Bursa well-developed, anteriorly closed, transversely and longitudinally striated with dot-like punctations. Anterior bursal rim close to cloacal opening, bursal velum appearing lobed under LM, forming two deep grooves at GP2 and GP5. Phasmids relatively plump and shorter, located in between GP5 and group of GP6–8. Genital papillae GP6–8 basally fused. Dauer/phoretic juvenile Body often straight or slightly ventrally arcuate upon fixation. Cuticle thin, ca 0.1–0.5 μm. Lateral field inconspicuous. Lip region continuous. Lips amalgamated, not differentiated into six separate lips. Oral aperture covered by a highly sclerotized cuticular plug. Stoma long, narrow, ca 5–6 times as long as wide. Metastegostomal swellings with faintly visible denticles. Pharynx weakly developed with slender procorpus 42–56 μm long; a swelling metacorpus 11–15 ×10–12 μm in dimension and a narrow, long, isthmus of 25–36 μm, expanded posteriorly to an oval basal bulb 15–25 ×12–17 μm in dimension, having weakly-developed grinder. Nerve ring encircling mid or posterior region of isthmus. Secretory-excretory duct inconspicuous. Cardia short, conoid. Rectum shorter than anal body diameter. Rectal glands inconspicuous. Phasmidial aperture inconspicuous. Tail long, conoid, ending with a sharp, pointed tip. Remarks Pelodera indica sp. nov. comes closer to P. cylindrica (Cobb, 1898) in most of the morphometric and morphological characters but differs in having females with smaller c (14.7–21.1 vs 38.6–70.9) and greater c’ (1.1–1.8 vs 0.5–0.6) values; tail cupola-shaped (vs hemispheroid) with (vs without) spike and males with spicules having rounded (vs elongated) capitula, fused up to 24–28% (vs 15–20%) at distal end; bursa lobed (vs not lobed in P. cylindrica fide Sachs (1950), Völk (1950) and Osche (1952)). The new species resembles P. isociensis (Maupas, 1916) in most morphometric characters but differs in having smaller females (849–1065 μm vs 1214–1830 μm); smaller c (14.7–21.1 vs 30.3–57.3) value; tail spike as long as (vs one third) of anal body diameter; males with GP2 and GP3 relatively closer (vs spaced in P. isociensis fide Sachs (1950)). The new species also differs from P. tretzeli (Sachs, 1950) in having females with smaller body (849– 1065 μm vs 1543–3327 μm); smaller b (5.1–6.2 vs 8.1–11.9) and c (14.7–21.1 vs 28.4–33.1) values; phasmids present at level of (vs posterior to) anus; males with smaller c (13.8–18.1 vs 28.4–35.6) value; larger spicules (45–57 μm vs 32–39 μm); pre cloacal genital papillae absent (vs present); GP3 close to (vs distant from) GP4; bursa with two notches (vs one notch) and anterior rim of bursa close to (vs distant from cloacal opening in P. tretzeli fide Sachs (1950)). Pelodera indica sp. nov. differs from P. voelki (Sachs, 1950) in having females with smaller body (849– 1065 μm vs 1470–3610 μm), smaller b (5.1–6.2 vs 7.6–9.6) and c (14.7–21.1 vs 25.8–36.3) values; males having smaller body (591–727 μm vs 885–1625 μm), and relatively smaller b (4.1–5.3 vs 5.3–6.1) and c (13.8–18.1 vs 21.6–26.7) values; smaller spicules (45–47 μm vs 51–70 μm); genital papillae compactly placed (vs spaced); pre cloacals absent (vs present); GP2 relatively plump (vs slender); GP2 and GP3 closely (vs distantly) placed; anterior bursal rim just ahead of cloaca (vs distant from cloaca in P. voelki fide Sachs (1950)). The new species differs from P. aligarhensis Tahseen et al., 2014 in having females with relatively larger body length (849–1065 μm vs 688–841μm); greater b (5.1–6.2 vs 3.9–4.6) and relatively smaller c (14.7–21.1 vs 22.1–41.2) values; longer tail spike (20–31 μm vs 5.9 μm); males with larger spicules (45–57 μm vs 30–38 μm); anterior bursal rim just anterior to (vs distant from) cloacal opening; pre cloacal genital papillae shifted (vs not shifted) posterior to cloaca; genital papillae not arranged in groups (vs arranged in three groups in P. aligarhensis).Published as part of Mahboob, Mohammad, Jahan, Rehmat & Tahseen, Qudsia, 2023, Comparative and cladistic analyses of the species of the genus Pelodera Schneider, 1866 (Rhabditidae: Nematoda) belonging to the coarctata group, pp. 71-114 in European Journal of Taxonomy 890 (1) on pages 74-80, DOI: 10.5852/ejt.2023.890.2253, http://zenodo.org/record/828352
Figure 1 in A revision of the genus Metarhabditis (Nematoda: Rhabditidae) with description of three known species, a key to the identification of congeners and discussion of their relationships
No full textFigure 1. Metarhabditis costai (Martins, 1985) Sudhaus, 2011. (A) Entire female; (B) entire male; (C) anterior region; (D) pharyngeal region; (E) female genital branch; (F) female tail region; (G) male tail region.Published as part of Asif, M., Prasad, J.S., Khan, R., Somasekhar, N. & Tahseen, Q., 2013, A revision of the genus Metarhabditis (Nematoda: Rhabditidae) with description of three known species, a key to the identification of congeners and discussion of their relationships, pp. 2599-2622 in Journal of Natural History 47 (41-42) on page 2601, DOI: 10.1080/00222933.2013.798702, http://zenodo.org/record/519785
Attraction and preference of bacteriophagous and plant-parasitic nematodes towards different types of soil bacteria
No full textFigure 4. (A) Preference of Acrobeloides maximus for different bacterial isolates; (B) preference of Caenorhabditis elegans for different bacterial isolates; (C) preference of C. elegans for different bacterial isolates for egg laying (see Table 1 for colony code).Published as part of Tahseen, Qudsia & Clark, Ian Michael, 2014, Attraction and preference of bacteriophagous and plant-parasitic nematodes towards different types of soil bacteria, pp. 1485-1502 in Journal of Natural History 48 (25-26) on page 1493, DOI: 10.1080/00222933.2013.873088, http://zenodo.org/record/463139
Pelodera adeeli Mahboob & Jahan & Tahseen 2023, sp. nov.
No full textPelodera adeeli sp. nov. urn:lsid:zoobank.org:act: 40B1FCCA-69E5-4C95-957D-3B40DD68E7F2 Figs 4–6, 13–15; Tables 2, 5–6; Appendices 1–2 Diagnosis The new species P. adeeli sp. nov. is characterized by the absence of sexual dimorphism in anterior region; cuticle transversely and longitudinally striated; lips equal, strongly offset with loose cuticular margins; stoma 4.5–5.0 times as long as wide with three well-developed, relatively small setose denticles on each metastegostomal plate; secretory-excretory pore located nearly at level of pharyngo-intestinal junction; distal ends of ovaries crossing each other; vulval lips strongly protruded; tail paedomorphic with retention of juvenile cuticle, conoid, regularly tapering to acute terminus; males with slender spicules, rounded capitulum, long neck, shaft fused distally; gubernaculum ca ⅓–¼ of spicule length; bursa peloderan, anteriorly closed and punctated with serrated margins, anterior rim of bursa distant from cloacal opening; genital papillae nine pairs: two pre cloacal and seven post cloacal pairs arranged in 2/1+2+Ph+3+1 configuration with wide gap between GP2, GP3 and GP4. Etymology The species name is given in honour of Mr Mohammad Adeel, the father of Mohammad Mahboob. Material examined Holotype INDIA • ♂; Eastern Uttar Pradesh, Terai region, District Gonda; 27°08′37.38″ N, 82°38′59.65″ E; 309 m a.s.l.; isolated from the elytra (front wing) of dung beetle, Onthophagus ramoss (Wiedeman, 1823) (Coleoptera: Scarabaeidae) (the beetle specimens were destroyed due to dissection/excision); AMU/ZD/ NC slide no. Pelodera adeeli sp. nov. /NIT/rpt/1. Paratypes INDIA • 3 ♂♂, 5 ♀♀, 5 juvs; same collection data as for holotype; AMU/ZD/NC slide no. Pelodera adeeli sp. nov. /NIT/rpt/2–10. Description Adult Body medium-sized, obese, stout, almost straight, tapering at both extremities. Cuticle annulated, 2 μm thick with annules 1.0–1.5 μm wide at pharyngeal region and 3–4 μm wide at mid-body. Longitudinal striations relatively prominent, extending up to tail, crossed by transverse striation to form corn cob pattern. Sexual dimorphism indistinct in anterior region with lip region offset from body contour and 2.5–3.0 times as wide as high. Lips six, equal-sized with loose margins, globular in shape, distinctly separated, containing slightly raised labial sensilla. Amphids labial with small, rounded apertures. Stoma well-developed, ca 4.5–5.0 times as long as wide or 13–14% of total pharyngeal length. Cheilostom highly cuticularized; gymnostom relatively narrower than stegostom; stegostom more than half of stoma length, surrounded by pharyngeal tissue at about 56.5–57.4% of stoma length; metastegostom with three prominent setose denticles on each swelling; telostegostom heavily cuticularized. Pharynx well-developed, divided into muscular, 60–66 μm long, slender corpus, well-developed, highly muscular metacorpus of 22–26 ×21–25 μm dimension, and isthmus relatively narrower, 40–45 μm long, expanding posteriorly to form well-developed basal bulb of 27–32×24–26 μm dimension, having a grinder and double-chambered haustrulum. Cardia conoid, 5–7 μm long. Nerve ring encircling posterior region of isthmus at 67.8–68.7% of pharyngeal length from anterior end. Secretory-excretory duct usually opening posterior to pharynx at 96.2–105% from anterior end. Intestine with wide lumen, often anteriorly and posteriorly dilated to form bacterial pouches with intestinal epithelim thinning out in the region; intestinal lumen refractive. Rectum 24–28 μm long, approximately equal to anal body diameter, occasionally with dilated lumen. Tail paedomorphic, retaining larval cuticle, conoid in shape, ca twice of anal body diameter. Phasmids tubular, opening slightly posterior to anus. Female Reproductive system didelphic, amphidelphic; ovaries well-developed, paired, opposed, and lateroventrally reflexed, usually distal ends of ovaries extended beyond vulva, crossing each other. Oocytes with prominent nuclei arranged in multiple rows. Usually, two uterine eggs present at different stages of embryonation. Vagina thick-walled. Vulva rounded in shape with strongly protruded vulval lips, situated posterior to the mid-body or at 57.7–60.0% from the anterior end. Male Similar to female in general morphology except prominently curved posterior region. Testis single, dorsally reflexed, on right lateral side of intestine. Spermatocytes arranged in multiple rows. Seminal vesicle filled with spermatids continuing into vas deferens. Vas deferens narrowing posteriorly to form a narrow ejaculatory duct. A pair of ejaculatory glands present. Tail conical, ending in an acute terminus. Bursa well-developed, anteriorly closed, oval in shape, transversally and longitudinally striated with dot-like punctations. Bursal margins crenate. Anterior bursal velum distant from cloacal opening. Spicules slightly ventrally curved, slender with rounded capitulum, narrow necks and conspicuous ventral conoid process, fused distally up to 20–22% of total length. Gubernaculum slender, trough-shaped, ca 22–25% of spicule length. Genital papillae nine pairs in 2/1+2+P+3+1 configuration. Pre cloacals GP1 and GP2 similar in shape and size, directed towards anterior velum of bursa. GP3 situated just posterior to cloaca. GP4, GP5 and phasmid closely placed while GP4 far from GP3. Phasmid relatively shorter and plump, GP6–8 basally fused, equal in shape and size. GP9 open dorsally, close to group of GP6–8. Dauer/phoretic juvenile Body straight, tapering at both extremities, more towards posterior region. Cuticle thin, ca 0.1–0.3 μm. Lateral field with single line or incisor. Lip region continuous. Stoma long, narrow, ca 6–7 times as long as wide. Metastegostomal swellings weakly-developed with faintly visible small denticles. Pharynx well-developed with slender procorpus 38–45 μm long, a swollen metacorpus of 12–15 μm× 11–12μm dimension and a narrow, long isthmus of 28–32 μm, expanded posteriorly to an oval basal bulb of 15– 17 μm ×12–12 μm dimension, having weakly-developed grinder. Nerve ring encircling mid-region of isthmus. Secretory-excretory duct inconspicuous. Bacterial chamber present. Rectum shorter than anal body diameter. Rectal glands prominent. Tail long, conoid, ending with filiform tip. Remarks Pelodera adeeli sp. nov. comes closer to P. cylindrica (Cobb, 1898) in most morphometric and morphological characteristics but differs in sexual dimorphism absent (vs present); females having smaller c (12.5–17.2 vs 38.6–70.5) and greater c’ (1.7–2.1 vs 0.5–0.6) values; labial sensilla slightly raised (vs minute); metastegostomal denticles relatively smaller (vs larger); lip margins loose (vs defined); posteriorly located secretory-excretory pore 96.2–105.0% (vs 53–75%) of pharyngeal length; tail conoid (vs hemispheroid); males with pre cloacal genital papillae not shifted posteriorly (vs shifted posteriorly in P. cylindrica fide Sachs (1950) and Völk (1950)). The new species differs from P. par Andrássy, 1962 in having females with smaller a (11.6–13.9 vs 18.5), b (4.2–5.4 vs 7.1) and c (12.5–17.2 vs 27.5) values; labial sensilla raised (vs minute); stegostom slightly (vs strongly) expanded; tail conoid (vs cupola-shaped); males with smaller a (13.4–16.8 vs 22.7) and c (15.6–19.4 vs 21.0) values; gubernaculum ca ⅓–¼ of spicule length (vs half of spicule length); pre cloacal genital papillae 2 pairs (vs 3 pairs in P. par). The new species resembles P. cystilarva (Völk, 1950) but differs in having females with smaller body size (678–934 μm vs 1224–1744 μm); smaller b (4.2–5.4 vs 6.2–7.6) and c’ (1.7–2.1 vs 2.6–6.7) values; greater c (12.5–17.2 vs 7.5–9.1) value; stoma 4.5–5.0 times (vs 6–7 times) as long as wide; rectum approximately equal to (vs half or less than) anal body diameter; tail conoid (vs dome-shaped); males with smaller body (577–722 μm vs 880–1072 μm); greater a (13.4–16.8 vs 11.5–12.0) value; smaller b (4.0–4.8 vs 5.0–5.4) and c (15.6–19.4 vs 26.1–46.3) values; bursal velum expanded (vs relatively converging type in P. cystilarva fide Völk (1950)). Pelodera adeeli sp. nov. comes close to P. serrata (Körner in Osche, 1952) but differs in having females with smaller body size (678–934 μm vs 1148–1409 μm); smaller c (12.5–17.2 vs 37.0–50.7) value; secretory-excretory pore located at level of pharyngo-intestinal junction (vs at mid-level of isthmus); tail conoid (vs cupola-shaped); males with body shorter (577–722 μm vs 1067–1242 μm); relatively smaller b (4.0–4.8 vs 4.8–5.9) and c (15.6–19.4 vs 29.3–41.0) values; smaller spicules (37–50 μm vs 68–80 μm) and genital papillae GP3 and GP4 distantly positioned (vs closely placed in P. serrata fide Körner in Osche (1952)). The new species differs from P. voelki (Sachs, 1950) in having no sexual dimorphism (vs sexual dimorphism present); females with smaller body size (678–934 μm vs 1470–3610 μm); smaller b (4.2– 5.4 vs 7.6–9.6) and c (12.5–17.2 vs 25.8–36.3) values; metastegostomal denticles relatively small (vs long); stoma 4.5–5.0 times (vs 2.5–3.0 times) as long as wide; tail conoid (vs cupola-shaped); males shorter (577–722 μm vs 885–1625 μm), with relatively smaller a (13.4–16.8 vs 16.3–20.0), b (4.0–4.8 vs 5.3–6.1) and c (15.6–19.4 vs 21.6–26.7) values; smaller spicules (37–50 μm vs 51–70 μm); genital papillae GP1 and GP2 distant (vs close) to cloaca and GP3 distant from GP4 (vs close to GP 4 in P. voelki fide Sachs (1950)). The new species also differs from P. kolbi (Sachs, 1950) in not showing (vs showing) sexual dimorphism; females with smaller body length (678–934 μm vs 1185–1326 μm); smaller b (4.2–5.4 vs 5.9–7.9) and c (12.5–17.2 vs 21.9–27.9) values; greater c’ (1.7–2.1 vs 0.9–1.0) value; tail conoid (vs cupola-shaped); males with relatively smaller a (13.4–16.8 vs 16.1–18.1) value; genital papillae GP1 inside (vs outside) bursa; pre cloacal genital papillae (two pairs vs single pair); GP2 distantly ahead of cloaca (vs at level of cloaca) and GP4–5+P and GP6–8 arranged in groups (vs not arranged in groups in P. kolbi fide Sachs (1950)). Pelodera adeeli sp. nov. differs from the Indian species, P. aligarhensis Tahseen et al., 2014, in having sexual dimorphism absent (vs present); smaller a (11.6–13.9 vs 16.3–20.0) and c (12.5–17.2 vs 22.1– 41.2) values; relatively greater c’ (1.7–2.1 vs 0.8–1.4) value; labial margins wavy (vs compact); denticles relatively small (vs large); tail conoid (vs cupola-shaped); males with smaller a (13.4–16.8 vs 17.5–18.4) value; adcloacal papilla absent (vs present); GP3 distant (vs close to GP 2 in P. aligarhensis).Published as part of Mahboob, Mohammad, Jahan, Rehmat & Tahseen, Qudsia, 2023, Comparative and cladistic analyses of the species of the genus Pelodera Schneider, 1866 (Rhabditidae: Nematoda) belonging to the coarctata group, pp. 71-114 in European Journal of Taxonomy 890 (1) on pages 80-87, DOI: 10.5852/ejt.2023.890.2253, http://zenodo.org/record/828352
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
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