Xiphinema llanosum and Trophurus vultus, Two New Plant Nematode Species from Pasture Soils in Colombia

Xiphinema llanosum n. sp. and Trophurus vultus n. sp. are described and illustrated from grass soils in Llanos Orientales, Colombia. Xiphinema llanosum is a bisexual species. The female body length is 2.3-2.7 mm, odontostyle 86-96 μm, and odontophore 58-65 μm long; vulva at 42-47%; anterior ovary is absent; the anterior uterus and oviduct are similar to the posterior branch but slightly reduced; and the tail is dorsally convex-conoid with a blunt hemispherical terminus. Male body length is 2.06-2.96 mm; spicules are 40-44 μm long; and four (rarely three or five) anterior ventromedian supplementary papillae are present. Trophurus vultus females are 0.52-0.67 mm long; vulva at 56-60%; stylet is 10.5-13.5 μm long; isthmus is as long as the basal esophageal bulb; the tail is subclavate, 1.6-2.2 times anal body width long; and the terminal cuticle thickness is about one-sixth of the tail length.     

Margollus bokanicus n. sp. from Iran,the Fourth Species of a Rare Nematode Genus (Dorylaimida,Tylencholaimellidae)

Margollus bokanicus n. sp., collected from natural habitats in Khorasaneh district, Bokan, West Azarbaijan province, Iran, is described. Morphological and morphometric data are provided as well as drawings and light microscopy illustrations. The new species is characterized by a medium size body length (0.60 to 0.73 mm), labial and postlabial sclerotizations, lip region 7-μm wide, offset by constriction and long neck (167 to 207 μm), long pharyngeal basal bulb (27 to 36 μm) or 16% to 17% of total neck length, female genital system monodelphic–opisthodelphic, anterior branch reduced to a uterine sac (26–29 μm) or 1.1 to 1.3 times the body diameter, long posterior uterus (25–28 μm) or 1.1 to 1.3 times the body diameter, V = 40 to 47, cylindroid female tail (17 to 24 μm, c = 31 to 38, c’ = 1.1 to 1.4), and males unknown. This taxon is easily distinguishable from other Margollus species by its smaller general size and more posterior vulva. A compendium of Margollus species is also presented.     

Description of Meloidoderita polygoni n. sp. (Nematoda: Meloidoderitidae) from USA and Observations on M. kirjanovae from Israel and USSR

Meloidoderita polygoni n. sp. is described and illustrated from roots of smartweed (Polygonum hydropiperoides) from Beltsville, Maryland. This new species is similar to M. kirjanovae but differs especially in having larger spines on the cystoid bodies, females with the anus much closer to the vulva, and more posterior excretory pore. M. polygoni differs from M. safrica particularly in having females with a shorter stylet, a DGO much closer to base of stylet, greater distance between vulva and anus, and larger cystoid bodies. LM and SEM observations showed only three incisures in lateral fields of juveniles and males and no bursa in males. Morphometric data and illustrations are given for M. kirjanovae from mint (Mentha longifolia) in Israel and some details on a limited number of specimens from Armenian SSR. LM examination of juveniles from both these areas indicated only three incisures in lateral fields. Males from Israel had no detectable bursa and appeared to have only three incisures in lateral fields. (Males from Armenian SSR not observed.)     

Filenchus flagellicaudatus n. sp. and Lelenchus schmitti n. sp. (Nemata: Tylenchidae) from Molokai,Hawaii

Filenchus flagellicaudatus n. sp. and Lelenchus schmitti n. sp. are described from Pepe''opae bog on Molokai, Hawaii. Filenchus flagellicaudatus n. sp. is distinguished from all other Filenchus spp. by stylet length (10 µm), robust metacorpus, elongated basal bulb, and extraordinarily long, whip-like tail (c = 2.6, c'' = 31.8). Lelenchus schmitti n. sp. differs from other Lelenchus spp. by its shorter body length, weak dorso-ventral compression of the head region, and a more posterior vulva (V = 49-52). The spacious amphid pocket is introduced as a useful character for the differentiation of Lelenchus spp. from other Tylenchidae.     

Two New Species of Tylenchidae,Basiroides nortoni n. sp. and Tylenchus hageneri n. sp. (Nematoda: Tylenchida)

Basiroides nortoni n. sp. and Tylenchus hageneri n. sp. from soil around roots of corn from Ollie, Iowa, are described and illustrated. B. nortoni n. sp. has a posterior vulva, a long posterior uterine branch and an arcuate tail with pointed terminus. T. hageneri n. sp. has four lines in the lateral field, coarse transverse cuticular striae along the whole body, and a filiform tail slightly shorter than vulva-anus distance.     

The Excretory Systems of Three Ditylenchus spp.

In Ditylenchus dipsaci the morphologically different anterior and posterior regions of the terminal excretory duct are separated by a constriction. Immediately posterior to the constriction is a valve-like structure composed of dense pieces integral with the wall of the duct. The posterior region is sometimes dilated at intervals along its length. The same structures are present in D. myceliophagus and D. destructor, but the dense pieces appear less well developed. A possible mode of action for the excretory system is discussed.     

Morphological Variation in Xiphinema spp. from New York Orchards

Xiphinema specimens were collected from orchards in southeastern, northeastern, and western New York. Total length, distance of vulva from anterior end, spear length (odontostyle plus odontophore), body diameter at vulva, tail length, anal body diameter, and length and diameter of hyaline tail tip were measured on fixed, glycerol-infiltrated adult females. Most specimens were identified as X. americanum or X. rivesi, but one western New York population was identified as X. californicum (a new record for New York). Multivariate analyses indicated that, with one exception, western New York populations of both X. americanum and X. rivesi were smaller and slimmer than their eastern counterparts. Regional differences were generally larger than differences attributed to host species.     

Trichodorus elefjohnsoni n. sp. (Nemata: Trichodoridae) from Undisturbed Appalachian Forest

A new species of Trichodoridae, Trichodorus elefjohnsoni, is described from undisturbed regions of Great Smoky Mountains National Park, United States. It resembles T. orientalis De Waele &Hashim, 1984, T. persicus De Waele &Sturhan, 1987, and T. taylori De Waele, Mancini, Roca, '' Lamberti, 1982 in arrangement of ventromedian cervical papillae and posterior preanal supplements, but differs by combinations of the following characteristics: body length 516-731 μm; spicule length 33-50 μm, spicules densely striated, constricted medially; vaginal sclerotizations ovate; one pair of lateral body pores near vulva.     

Description of Pratylenchus gutierrezi n. sp. (Nematoda: Pratylenchidae) from Coffee in Costa Rica

A lesion nematode, Pratylenchus gutierrezi n. sp., collected from the roots of coffee in the Central Plateau of Costa Rica, is described and illustrated. Its relationships to Pratylenchus flakkensis, P. similis, and P. gibbicaudatus, the only other species of the genus having two head annules, males, or spermatheca with sperm, and an annulated tail terminus, is discussed. Other distinctive characters are its posterior vulva (mean of 80%); its prominently rounded stylet knobs, low head, and subcylindrical tail. SEM observations provide additional details of females and males, especially face views, which show for the first time sexual dimorphism.     

Description of Thecavermiculatus andinus n.sp. (Meloidoderidae), a Round Cystoid Nematode from the Andes Mountains of Peru

Thecavermiculatus andinus n.sp. is described and illustrated from Oxalis tuberosa originally collected in the vicinity of Lake Titicaca high in the Andes mountains of southern Peru. This new species differs markedly front the other two species in the genus, especially in having a much greater female vulval-anal distance and annules with lined punctation on most of the female body with a lacelike pattern restricted to the posterior portion, particularly at the vulva and anus which do not protrude. Females are essentially spherical with protruding neck, white to yellowish in color, and can easily be mistaken for potato cyst nematodes. Among the dozen or more known weed and crop host plants are potato and eggplant. In order to accommodate this new species, the genus Thecavermieulatus is emended. A key to the species of this genus is presented.     

First Record of Cosmocephalus obvelatus (Acuariidae) in Common Gulls (Larus canus) from Gangneung,Korea

A nematode species belonging to the genus Cosmocephalus was collected from the stomach of 2 common gulls, Larus canus. The common gulls were found dead on the seaside of Gangneung City, the Republic of Korea. The worms were identified and classified by light (LM) and scanning electron microscopy (SEM) on the basis of important taxonomic characters. The nematodes were characterized by a body length 9.1-9.3 mm (males) and 15.5-15.9 mm (females) and cordons recurrent in anterior direction and anastomosing laterally at about the level of anterior quarter of the buccal cavity. The salient bicuspid deirids were located on the posterior to the cordons. Lateral alae were well-developed, extending from the level just posterior of deirids to the level about middle of the body. LM and SEM observations identified the worms as C. obvelatus. This is the first reported case of C. obvelatus infection in common gulls in Korea.     

Description of Afenestrata koreana n. sp. (Nematoda: Heteroderinae), a Parasite, of Bamboo in Korea

Afenestrata koreana n. sp. collected from roots of bamboo (Phyllostachys pubescens) in Gyeongnam Province in the southern part of the Korean peninsula is described and illustrated. Its primary differentiating characteristics are a globose to subspherical body in adults with a prominent neck and terminal cone, thick cuticle, terminal vulva, and deep vagina. Fenestra, bullae, and underbridge are absent. The anus is on the immediate posterior side of the cone. Superficial small tubercules cover all the terminal cone area. The new species differs markedly from the other two known species in the genus, specifically in having three incisures in the lateral field of juveniles and a shorter stylet length in juveniles and adults. The male is unknown.     

Three New Species of the Super Family Neotylenchoidea (Nematoda: Tylenchida) from Pakistan

Three new species in the super family Neotylenchoidea collected in Pakistan during 1979-80 are described. New species Nothotylenchus gohleni is related to N. affinis Thorne, 1941 but is differentiated by its longer, more robust body with tine cuticular annules, a more posterior vulva, inconspicuous basal knobs of the stylet, and poorly developed metacorpal area. N. geraerti and N. tuberosus are also close to this undescribed species, hut they have a more developed metacorpal area and a larger post uterine sac. Boleodorus zaini n.sp. is distinguished by its excretory pore open at a level with the base of the posterior esophageal bulb and by six distinct lines in the lateral field. Paurodontella sohailai n.sp. is closely related to P. densa (Thorne, 1941) Hussain &Khan, 1967 and P. minuta Hussain &Khan, 1967 but differs from them by its larger body, shape of tail, and seven incisures in the lateral field.     

Meloidogyne trifoliophila n. sp. (Nemata: Meloidogynidae), a Parasite of Clover from Tennessee

Meloidogyne trifoliophila n. sp. is described from white clover collected at Ames Plantation, Fayette County, Tennessee. The perineal pattern is rounded, with long, smooth striae and rounded arch, and without distinct lateral lines or perivulval striae. The female stylet is 12.6-15.5 μm long, the excretory pore is level with or up to one stylet length posterior to the stylet knobs, and the vulva is subterminal. The posterior terminus is weakly protuberant. The male lateral field is composed of approximately eight repeatedly broken or forked incisures. The male stylet is 17.0-18.9 μm long, the stylet knobs are rounded and sloping, gradually merging with the shaft, and the head region consists of one large annule. Second-stage juveniles are 357-400 μm long, with a stylet length of 11.9-13.6 μm and one head annule. The tail tapers to a slender tip. This new species is similar to M. graminicola and M. triticoryzae but differs from them in perineal pattern and lateral field morphology, and numerous morphometric characters.     

Ochoterenella esslingeri n. sp. (Nematoda: Onchocercidae: Waltonellinae) from Bokermannohyla luctuosa (Anura: Hylidae) in Minas Gerais,Brazil, with notes on Paraochoterenella Purnomo & Bangs, 1999

The waltonelline Ochoterenella esslingeri n. sp., a filarial parasite of the anuran Bokermannohyla luctuosa in Minas Gerais, Brazil is described. Several characters distinguish this new species from the 15 species presently included in the genus: the cuticular ornamentation of the female that is restricted to the posterior region of the body, the irregular arrangement of the small, rounded bosses, the postoesophageal vulva, the short glandular oesophagus, the size and shape of the microfilariae, the long left spicule and high spicular ratio. Irregularly arranged, tiny, rounded bosses are common in the monotypic genus Paraochoterenella from an Indonesian ranid, which is not well defined but likely valid. In the Neotropical Realm, the type hosts of the species of Ochoterenella are Hylidae (O. esslingeri n. sp.), Leptodactylidae (two species) and the remaining 13 species were described from the giant toad Rhinella marina (Bufonidae).     

Funaria maryanneae n. sp. and Proleptonchus weischeri n. sp. (Nematoda: Dorylaimida) from Europe and New Synonyms in Leptonchoidea

Funaria maryanneae n. sp., distinguished by its large size and long prerectum, is described from specimens collected in Bad Sooden, Germany, D. B. R. This nematode was collected also from Fräkmüntegg (Mt. Pilatus), Switzerland. Proleptonchus weischeri n. sp., with short hemispheroid female tail and relatively anterior vulva, is described from specimens collected in Kaufunger Wald near Kassel, Germany, D. B. R. This is the first report of either genus from the continent of Europe. Leptonchus parisii Zullini, 1973, from Chiapas, Mexico, becomes a junior synonym of Funaria obtusa (Thorne, 1939) Goseco, Ferris and Ferris, 1974. Leptonchus acutus Zulliui, 1973 becomes Funaria acuta n. comb., and Funaria rothi Goseco, Ferris and Ferris, 1974 becomes a junior synonym of Funaria acuta.     

New Species of Cyst Nematode Heterodera pakistanensis (Nematoda: Heteroderidae) Attacking Wheat in Pakistan

Heterodera pakistanensis n. sp., described and illustrated from roots of common wheat (Triticum aestivum) from Sukkur, Sind, Pakistan, belongs to the goettingiana group. It is most closely related to H. cyperi Golden, Rau &Cobb, 1962, H. raskii Basnet & Jayaprakash, 1984, and H. mothi Khan &Husain, 1965. Second-stage juveniles (J2) can be distinguished from H. cyperi J2 by an areolated lateral field with four incisures and shorter stylet, whereas cysts are separated by a more elongated vulva slit and the conspicuous structure of the underbridge. It differs from H. raskii by having four areolated lateral lines in J2, smaller female lemon-shaped cyst, shorter fenestra length and width, conspicuous underbridge, and distinct anus with a high cuticular pattern 40-45 μm from posterior end. It also differs from H. mothi by the presence of four areolated lateral lines in J2 and absence of vulva denticles and bullae.     

Diplogasteroides asiaticus n. sp. is Associated with Monochamus alternatus in Japan

Diplogasteroides asiaticus n. sp. is described and illustrated, and its molecular profile and phylogenetic status within the family Diplogastridae are inferred. Morphologically, the new species is characterized by its stomatal structure, a tube-like stoma with three small, rod-like dorsal teeth and two subventral ridges; a spicule clearly ventrally bent at 1/3 from the anterior end; a gubernaculum with a rounded anterior end and sharply pointed distal end in lateral view; nine pairs of genital papillae with an arrangement of <v1, (v2, v3d), C, v4, ad, ph, (v5, v6, v7), pd>; a short tail spike in males; and a well-developed receptaculum seminis, i.e., the antiparallel blind sacs of the uteri beyond the vulva region and elongated conical tail in females. This new species is morphologically similar to D. haslacheri, but it can be distinguished by the morphology of the somewhat shorter tail in females. D. asiaticus n. sp. shares high sequence conservation with D. andrassyi as there is only one base pair difference in the nearly full-length 18S rDNA and seven base pair differences in the D2-D3 expansion segments of the 28S rDNA. Despite this sequence conservation, the species status of D. asiaticus n. sp. was confirmed using the biological species concept, as D. asiaticus n. sp. and D. andrassyi failed to generate viable F₂ progeny in hybridization tests.     

lin-17/Frizzled and lin-18 regulate POP-1/TCF-1 localization and cell type specification during C. elegans vulval development

The Caenorhabditis elegans vulva is comprised of highly similar anterior and posterior halves that are arranged in a mirror symmetric pattern. The cell lineages that form each half of the vulva are identical, except that they occur in opposite orientations with respect to the anterior/posterior axis. We show that most vulval cell divisions produce sister cells that have asymmetric levels of POP-1 and that the asymmetry has opposite orientations in the two halves of the vulva. We demonstrate that lin-17 (Frizzled type Wnt receptor) and lin-18 (Ryk) regulate the pattern of POP-1 localization and cell type specification in the posterior half of the vulva. In the absence of lin-17 and lin-18, posterior lineages are reversed and resemble anterior lineages. These experiments suggest that Wnt signaling pathways reorient cell lineages in the posterior half of the vulva from a default orientation displayed in the anterior half of the vulva.