A New Species of Pratylenchus (Nemata-Tyleiichida) from Roots of Soybeans VIRGINIA R
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JULY, 1961] HELMINTHOLOGICAL SOCIETY 109 A New Species of Pratylenchus (Nemata-Tyleiichida) from Roots of Soybeans VIRGINIA R. FERRIS* During a routine check of Illinois soybean breeding plots in the summer of 1958, large numbers of a single species of Pratylenchus were obtained from the roots of nine varieties of soybeans in one field. The males of this species often outnumbered the females and comprised from 10% to 50% of an entire collection (which usually contained many larvae as well as adults). Subsequent investigation showed it to be a new species. It is de- scribed herein as Pratylenchus alleni n. sp., after Professor M. W. Allen. Specimens from the original collections were increased in the greenhouse on soybeans, wheat, and oats to provide material for study of its taxonomy and pathogenicity. Results of the pathogenicity studies will be reported elsewhere. The description and drawings are based on studies of botli living and preserved specimens. All measurements given are of specimens1 obtained from soybean roots. The nematodes were relaxed by gentle heat, killed and fixed in F.A.A., and dehydrated and mounted in glycerine using Thome's (1936) methods. Pratylenchus alleni, n. sp. DIMENSIONS: 10 females: L = 0.38 mm. (0.33-0.44); a = 23 (19-27); b = 5.4 (4.7-6.1) ; c = 20 (1.5-25) ; v = 3C804-8 (~8-4878-833-T-5-7) ; stylet = 14 microns (13.5-15). 10 males: L = 0.37 mm. (0.35-0.40) ; a = 26 (22-34) ; b = 5.3 (5.1-5.7) ; e = 20 (18-22); T = 45 (38-52); stylet = 13,6 microns (13.5-14.3). Female (Holotype) : L = 0.41; a = 22; b = 5.7; c = 21; v = 4H794-3; stylet = 14 microns. Male (Allotype) : L = 0.35; a = 24; b = 5.2; c = 22; T = 52; stylet = 13.5 microns. FEMALE: Lip region bluntly rounded, with 2 annules (one striation). Outer margins of sclerotized labial framework extend into the body about one body amrule. The spear-guiding apparatus extends posteriorly from the basal plate of cephalic armature about 3 body annules. Both anterior and posterior cephalids present. The anterior cephalic! is the larger of the two and is located at the second annule following the lip region. The posterior cephalid is located at about the 6th body annule. Stylet about 14 microns long-. Basal knobs well developed, flattened anteriorly (Fig. 1, A). Hemi- zonid just anterior to excretory pore about 2 annules long. Ovary consists usually of a double row of oocytes except for a short single row at either end. Spermatheca round, oviduct cellular from 1% to 3 times as long as spermatheca, uterus usually about as long as spermatheca. Posterior uterine branch slightly longer than the width of the body at the vulva. Vulva-anus distance equal to about 3 (2.3-4.2) times tail length. Phasmids anterior to middle of tail. Two (and sometimes 3) of the 4 lateral lines extend past "The author is indebted to Professor Gerald Thorne, Dept. Plant Pathology, Univ. of Wisconsin, Madison, Wisconsin, for his counsel and suggestions during the course of this work. Author's address: 2237 Delaware Drive, West Lafayette, Indiana. Copyright © 2011, The Helminthological Society of Washington 110 PROCEEDINGS OF THE [You 28, No. 2 phasmid. Tail without striations around terminus. Terminus usually with one or two indentations (Fig. 1, B) but sometimes smoothly rounded (Fig. 1, E). MALE : Similar to female. Spermatocytes arranged in double or triple rows. Phasmids, slightly anterior to middle of tail, may or may not extend slightly into bursa. Spicula arcuate, hafted, resting on a simple, trough- shaped gnbernaculum. DIAGNOSIS: Small (0.4 mm.) Pratylenclius with two annules in lip region. Males numerous. Spheroid spermatheca, present. Stylet about 14 microns long Avith anteriorly flattened knobs. Female terminus rounded. Most closely resembles P. mint/us Sher & Allen, 1953, which Loof, 1960, considers a synonym of P. neglectus (Rensch 1924) Chitwood & Oteifa 1952. It can be distinguished from this nematode by its numeixms males, by the spermatheca, and by the shorter stylet. It differs from P. coffeae by its small, stout body, shorter stylet, and round (never oval) spermatheca. TYPE SPECIMENS : Holotype, female, from soybean root collection originally made in Eldorado, Illinois, on August 27, 1958, by R. L. Bernard, and in- creased in pot cultures in the greenhouse by the author. Slide Pratylenchus Fig. 1. PratylencJius alleni: A, head of female; B and E, variations in female tails; C, part of female body showing vulva, uterus, oviduct, and spermatheca; D, posterior portion of female. F, male tail. Copyright © 2011, The Helminthological Society of Washington JULY, 1961] HELMINTHOLOGICAL SOCIETY 111 4. Dept. of Entomology Neinatode Collection, Purdue University, Lafayette, Indiana. Allotype, male, same data as holotype, Slide Pratylenclms 4 a, Purdue Dept. of Entomology Neinatode Collection. Paratypes, same data as holotype, 5 slides containing males, females, and larvae, deposited in Purdue Dept. of Entomology Neinatode Collection. TYPE HABITAT: Roots of soybeans (Git/cine max (L.) Merr.). TYPE LOCALITY: Soybean field 5 miles north of Eldorado, Illinois. LITERATURE CITED LOOF, P. A. A. 19(50. Taxonomic studies OH the genus Pratylenclms (Nematoda). T. PI. ziektoii (5(5 (1960) :29-90. SHER, S. A. and ALLEN, M. W. 1953. Revision of the genus Pratylenclms (Nematoda; Tylenehidae). Univ. of California Pubs, in Zoology 57:441-470. THORNE, G. and SAVANGER, H. IT. 1936. A monograph of the nematode genera Dorylainms Dujardin, Aporcelaimus n. g., 'Dorylaimoides n. g. and Pungentus n. g. Capita Zoologica Vol. VI, part 4. A New Moiiostome, Pleurogonius rnalaclernys., n. sp. (Trematoda: Pronocephalidae) from Beaufort, North Carolina WANDA SANBORN HUNTER* Twenty-three adult Carolina diamondback terrapins, Malaclcmys terrapin cent rat a (Latareille), 1802, were examined at the Duke University Marine Laboratory, Beaufort, N. C. Eight females (34.7%) carried a heavy infec- tion of a pronocephalid trematode described herein. These trematodes were located in the posterior third of the small intestine; 7 turtles yielded from 50 to 135 worms each, but only 2 were present in one host. The following description is based on study of man}' living and preserved Avorms which were killed in hot Avater without coA7er glass pressure. The measurements Avere made on 10 worms. Pleurogonius ttialaelenii/s, n. sp. (Fig. 1) Body elongate, relatively thick, Avith anterior end bluntly pointed and posterior extremity smoothly rounded. Cephalic collar inconspicuous; ventral lobes end somewhat less than one-quarter of body length, Avidely separated posteriorly, but joined medially about one-half distance behind oral sucker to form shallow concavity on anterior A'entral surface. Concavity of entire, body not pronounced in sections or in Avhole Avorms; sides of body mostly parallel betAveen collar and extreme posterior regions. Cuticle iion-spinous. Entire body surface glandular and dark Avith scat- tered pigment, heaviest in anterior, collar and oral sucker regions suggesting remnants of eye spots, particularly in younger Avorms. Length varies from 0.707 to 1.78 mm. (av. 0.935). Width at posterior end of cephalic collar ranges from 0.265 to 0.441 mm. (av. 0.342). Oral sucker Aveak, subspherical, measures from 0.061 to 0.078 by 0.059 to 0.089 mm. (av. 0.065 by 0.075). *Duke University. Durham, N. C., and the Duke University Marine Laboratory, Beaufort, N. 0. This investigation was supported by Duke University Research Council and in part by a research grant K700C-5, from the National Institute of Allergy and Infectious Diseases of the National Institutes of Health, Public Health Service. Copyright © 2011, The Helminthological Society of Washington.