Micha W. BRZESKI 1,, Ladislav HÁNEL 1,2,*, Andres I. NICO 3,4 and Pablo CASTILLO 3

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1 * Nematology, 1999, Vol. 1(4), Paratylenchinae: redescription of Paratylenchus arculatus Luc & de Guiran, 1962, a new senior synonym of P. nainianus Edward & Misra, 1963 (Nematoda: Tylenchulidae) Micha W. BRZESKI 1,, Ladislav HÁNEL 1,2,*, Andres I. NICO 3,4 and Pablo CASTILLO 3 1 Museum and Institute of Zoology PAS, Wilcza 64, Warszawa, and Research Institute of Vegetable Crops, Skierniewice, Poland; 2 Institute of Soil Biology, Academy of Sciences of the Czech Republic, Na sádkách 7, CZ ÏCeské Budejovice, Czech Republic; 3 Instituto de Agricultura Sostenible, CSIC, Apdo. 4084, Córdoba, Spain; 4 Facultad de Ciencias Agrarias y Forestales, UNLP, Cc 31, 1900-La Plata, Republica Argentina Accepted for publication: 9 December 1998 Summary Several populations of Paratylenchus arculatus from sandy soil and root samples from olive nurseries in southern Spain and from uncultivated clay soil in New South Wales, Australia are described. P. nainianus Edward & Misra, 1963 is considered as a junior subjective synonym of P. arculatus. Résumé Paratylenchinae: redescription de Paratylenchus arculatus Luc & de Guiran, 1962, un nouveau synonym majeur de P. nainianus Edward & Misra, 1963 (Nematoda: Tylenchulidae) Sont décrites plusieurs populations de Paratylenchus arculatus provenant d échantillons de sol sableux et de racines collectés dans des pépinières d olivier du sud de l Espagne et d un sol argileux en jachère des Nouvelles Galles du Sud, Australie. P. nainianus Edward & Misra, 1963 est considéré comme un synonyme mineur subjectif de P. arculatus. Keywords Australia, juvenile stages, olive nurseries, plant-parasitic nematodes, Spain, taxonomy. Paratylenchus arculatus was originally described from the Ivory Coast and probably not reported again. P. arculatus was again collected during a survey of plant parasitic nematodes from olive nurseries in southern Spain, where population density varied from nematodes per cm 3 of soil. Direct examination of feeder olive roots showed several females feeding ectoparasitically. The Spanish nematodes were compared and found conspeci c with specimens collected in New South Wales, Australia. The nematodes from Spain were killed by gentle heat and xed in 4% formaldehyde, while those from Australia were killed by pouring hot 2% formaldehyde over nematodes collected in a small drop of water. All nematodes were processed to glycerine using the methanol modi cation of the Seinhorst method. Paratylenchus arculatus Luc & de Guiran, 1962 = P. nainianus Edward & Misra, 1963 n. syn. See also Luc & de Guiran, 1962; Edward & Misra, 1963; Edward et al., 1967; Raski, 1975b) (Figs 1, 2) MEASUREMENTS See Tables 1 and 2. DESCRIPTION Female: Body curved ventrad up to almost O-shaped; females with longer gonad (apparently older) more curved than those with shorter gonad (younger). Cuticle with distinct transverse striae about 1 µ m wide. Lateral eld with four incisures beginning at the level of stylet and reaching the end of tail, about 2 µ m wide at spermatheca level. Head conical, striated, anteriorly truncate. Submedian lobes distinct, more or less projecting outward Professor M.W. Brzeski died 24 May Corresponding author, hanel@upb.cas.cz c Koninklijke Brill NV, Leiden,

2 M.W. Brzeski et al. Table 1. Measurements of females of Paratylenchus arculatus. (All measurements in µ m exept L in mm.) Spain New South Wales Mean [range] of means * Spain 107 Spain 110 Spain 201 Spain 203 Dareton 1 Dareton 2 Anabranch Wentworth (Range of extremes) n L 0.29 ± ± ± ± ± ± ± ± ± 0.02 [ ] ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) Stylet 26 ± ± ± ± ± ± ± ± ± 1.0 [24-28] (24-29) (25-29) (24-28) ( ) (25-28) (24-28) (24-26) (26-28) (21-32) Stylet cone 18 ± ± ± ± ± ± ± ± ± 0.6 [17-19] (16-20) (17-20) (16-20) (17-21) (17-20) (17-19) (16-18) (18-20) (16-21) m 69 ± ± ± ± ± ± ± ± ± 0.9 [68-71] (65-72) (64-74) (65-74) (65-74) (68-73) (69-73) (65-70) (67-70) (64-74) EP 66 ± ± ± ± ± ± ± ± ± 4.1 [57-67] (58-73) (46-68) (51-65) (50-73) (64-75) (60-73) (62-74) (63-74) (46-75) EP%L 23 ± ± ± ± ± ± ± ± ± 0.9 [21-24] (21-25) (21-26) (20-26) (19-27) (21-24) (22-24) (20-23) (22-24) (19-27) Pharynx 76 ± ± ± ± ± ± ± ± ± 1.9 [70-76] (66-85) (61-80) (62-83) (64-78) (67-78) (66-73) (64-76) (66-78) (61-85) Tail 24 ± ± ± ± ± ± ± ± ± 3.3 [13-24] (16-32) (9-22) (9-18) (9-18) (13-17) (13-19) (14-21) (14-18) (9-32) a 18.0 ± ± ± ± ± ± ± ± ± 2.2 [ ] (16-20) (14-22) (15-24) (15-23) (15-20) (17-22) (17-27) (21-24) (14-27) b 3.8 ± ± ± ± ± ± ± ± ± 0.3 [ ] ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) c 12.9 ± ± ± ± ± ± ± ± ± 2.2 [ ] (9-18) (12-27) (15-28) (15-24) (17-22) (16-20) (15-20) (16-20) (9-28) c 2.7 ± ± ± ± ± ± ± ± ± 0.3 [ ] ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) V 83 ± ± ± ± ± ± ± ± ± 0.5 [80-83] (81-85) (79-85) (79-84) (80-84) (81-84) (80-84) (81-84) (81-86) (78-86) * Including data of Luc & de Guiran (1962), Edward & Misra (1963), Edward et al. (1967) and Raski (1975b). Table 2. Measurements of juveniles of Paratylenchus arculatus. (All measurements in µ m except L in mm.) 2 nd stage 3 rd stage 4 th stage n L Stylet Stylet cone m EP EP%L Pharynx Tail a b c c , no observation. and appearing as the labial disc of Luc and de Guiran (1962). Excretory pore situated mostly 3-4 annuli posterior, but sometimes just posterior or anterior, to hemizonid, near the level of junction of isthmus and posterior bulb. Mean stylet cone length µ m (total range µ m) or 69-71% (total range 64-74%) stylet length. Stylet knobs triangular to rounded in outline. Dorsal gland ori ce 4-5 µ m posterior to stylet. Ovary outstretched, µ m long, rarely reaching or overlapping posterior bulb of pharynx. Spermatheca usually rounded ( µ m), rarely oval ( µ m), in majority of females lled with small globular sperm. Vagina walls not thickened, vagina bent anteriad, no post-vulval sac but uterine sac can surround vagina walls posterior to vulva. Vulval aps distinct, 3-4 µ m long, mostly rounded but sometimes attened. Body narrows posterior to vulva. Rectum very short, apparently not open to the outside and not serving as the end of digestive tract. Tail (measured from the place where rectum touches cuticle) slightly curved ventrad to almost straight, terminus striated, broadly rounded or indented on dorsal side, never pointed. Male: A single male found among some hundreds of females has the following measurements: L = 213 µ m, pharynx = 62 µ m, excretory pore = 49 µ m, tail = 8 µ m, a = 18, b = 3.4, c = 28.5, c = 1.0, spicules = 18 µ m, gubernaculum = 3.5 µ m. Body C-shaped. Cuticle with transverse striae about 1 µ m apart at midbody. Lateral eld with four incisures, about 2 µ m wide. 376 Nematology

3 Redescription of Paratylenchus arculatus Fig. 1. Paratylenchus arculatus. A: Variation of anterior end of female; B: Variation of posterior end of female; C: Female (Smaller unit of scale bar = 10 µ m). Head conical, anteriorly truncate, sublateral lobes less prominent than in females. Pharynx degenerate and nonfunctional, although median and posterior bulb could be seen. Excretory pore situated posterior to base of pharynx, canal lining less prominent than in females. Stylet not seen. Testis about 100 µ m long. Tail very short, terminus bluntly rounded, striated. Spicules thin, straight in anterior part, then curved ventrad, penial tube well developed. Juveniles: Body curved ventrad. Head, lateral eld and tail similar to female. Cuticular striae about 1 µ m apart. Sublateral lobes more pronounced in each consecutive developmental stage. Stylet and pharynx well developed Vol. 1(4),

4 M.W. Brzeski et al. in all postembryonic stages, probably functional. Fourth stage juveniles with numerous dark granules in body cavity and marked position of either developing vulva or spicules. The juvenile stages were identi ed based on the development of the gonad. LOCALITIES AND HABITATS The nematodes were collected from sandy soil and root samples from 3-4 month-old olive seedlings of the cultivars Arbequina, Picual and Hojiblanca in olive nurseries at Pedrera and Villaverde del Río, in Sevilla province, southern Spain. Other collections came from New South Wales, Australia, from uncultivated clay soil with mixed vegetation on the banks of the Murray river near Dareton, the Ana Branch of the Darling river, km N from Wentworth, and from Eucalyptus sp. soil from Six Mile Creek near Wentworth. Discussion The populations examined t the original description of P. arculatus from Ivory Coast (Luc & de Guiran, 1962) very well. The differences observed are a broader range of body length ( vs µ m in type population), indices a, b, c, V (in type population a = 16-25; b = ; c = 15-18; V = 81-84) and a slightly more posterior position of excretory pore in relation to pharynx end. The tail of P. arculatus was described as extrémité caudale de forme variable, présentant parfois un décrochement dorsal, and this was also observed in our material. Characters of the present populations which agree with P. arculatus are head with prominent sublateral lobes forming a disc-like labial structure, stylet length, shape and size of spermatheca lled with sperm, vulva position, distinct vulval aps, short tail with annulated terminus. The male was not found in the type series of P. arculatus. The similarity of the females examined led us to the conclusion that these are conspeci c with P. arculatus. This species should be compared with the following species of similar body and stylet length. Our specimens agree with P. nainianus Edward & Misra, 1963 in every respect. This species is characterised by the following measurements (composite data including Edward and Misra [1963], Edward et al. [1967], and Raski [1975b]): female L = µ m, a = 21-26, b = , c = 19-22, V = 78-86, stylet = µ m, excretory pore µ m; male L = µ m, a = 24-27, b = 4-5, c = , spicules µ m, gubernaculum 3 µ m, excretory pore µ m). The head of this species was described as somewhat conoid-truncate, striated, not sclerotized, continuous with the body contour and bearing six lips (Edward & Misra, 1963), but subsequent examinations show presence of sublateral lobes (Edward et al., 1967; Raski, 1975b). As the head structure, tail shape and all measurements are the same we consider P. nainianus as a junior subjective synonym of P. arculatus. P. nawadus Khan, Prasad & Mathur, 1967 is similar to P. arculatus as de ned above, but differs in having a distinctly tapering tail in both female and male. However, the tail shape of the females from olive nurseries in southern Spain which we examined is variable within each population, and some females could be regarded as P. nawadus. The male tail drawn by Khan et al. (1967) and in the present study (Fig. 2D) is different, but Fig. 2G of Edward et al. (1967) seems to represent an intermediate form. Composite measurements (including data of Khan et al. [1967], Raski [1975b], and Bajaj [1987]): female L = µ m, a = 18-28, b = , c = 12-16, V = 77-84, stylet µ m, excretory pore µ m; male L = µ m, a = 29-36, c = 13-14, spicules µ m, gubernaculum 3-5 µ m. P. nawadus was discussed and synonymised with P. nainianus by Misra & Edward (1971), but we prefer to regard them as two different species until more males are examined and the tail shape variability better known. P. obtusicaudatus Raski, 1975 appears similar to P. arculatus. The measurements (including data of Raski [1975a], Geraert and Ali [1978], and Bajaj [1987]) are: female L = µ m, a = 13-28, b = , c = 15-19, V = 81-86, stylet µ m, excretory pore µ m. The stylet of P. obtusicaudatus appears to be shorter than that of P. arculatus and the male is not known, indicating the two species may be distinct. Other species with similar measurements are easily separated by various combinations of head, stylet and tail structures and are not considered herein. Acknowledgements This research was supported in part by a grant from the Mianowski Fund, Warsaw, allowing one author (LH) to conduct this work at Skierniewice, and by a grant OLI from Comisión Interministerial de Ciencia y Tecnología (CICYT) of Spain and a grant from Agencia Española de Cooperación Internacional (AECI) of Spain for allowing another author (AIN) to conduct investigations 378 Nematology

5 Redescription of Paratylenchus arculatus Fig. 2. Paratylenchus arculatus. A: Anterior end of 2 nd stage juvenile; B: Anterior end of 3 rd stage juvenile; C: Anterior end of 4 th stage juvenile; D: Male (Smaller unit of scale bar = 10 µ m). Vol. 1(4),

6 M.W. Brzeski et al. on plant-parasitic nematodes in olive nurseries at Córdoba. References BAJAJ, H.K. (1987). On the species of Paratylenchus Micoletzky (Nematoda: Criconematina) from Haryana, India. Indian Journal of Nematology 17, EDWARD, J.C. & MISRA, S.L. (1963). Paratylenchus nainianus n. sp. (Nematoda: Criconematidae) from Uttar Pradesh, India. Nematologica 9, EDWARD, J.C., MISRA, S.L. & SINGH, G.R. (1967). Paratylenchus micoletzkyi n. sp. with the description of the allotype of P. nainianus Edward & Misra, Nematologica 13, GERAERT, E. & ALI, S.S. (1978). Observations on Paratylenchus aquaticus (syn. P. humilis) and P. obtusicaudatus from Africa. Mededelingen Faculteit Landbouwwetenschappen Riksuniversiteit Gent 43, KHAN, E., PRASAD, S.K. & MATHUR, V.K. (1967). Two species of the genus Paratylenchus Micoletzky, 1922 (Nematoda: Criconematidae) from India. Nematologica 13, LUC, M. & DE GUIRAN, G. (1962). Deux nouveaux Paratylenchus (Nematoda Criconematidae) de Côte d Ivoire. Nematologica 7, MISRA, S.L. & EDWARD, J.C. (1971). Two new species of the genus Paratylenchus with description of their larval stages and a note on P. nawadus a synonym of P. nainianus. Allahabad Farmer, 45: RASKI, D.J. (1975a). Revision of the genus Paratylenchus Micoletzky, 1922 and descriptions of new species. Part I of three parts. Journal of Nematology 7, RASKI, D.J. (1975b). Revision of the genus Paratylenchus Micoletzky,1922, and descriptions of new species. Part II of three parts. Journal of Nematology 7, Nematology