Pratylenchus australis n. sp. and Eutylenchus fueguensis n. sp. (Nematoda: Tylenchina) from southern Chile

Two new species of nematodes from southern Chile are described and illustrated. Pratylenchus australis n. sp. is distinguished by its heavy cephalic sclerotization, smooth tail terminus, lack of spermatheca, and absence of males. Eutylenchus fueguensis n. sp. differs from other Eutylenchus spp. by the long female stylet (31 [28-32] mum), strongly sclerotized excretory duct opening posterior to nerve ring, and broadly rounded caudal alae of males.

Hexamermis cathetospiculae n. sp. (Mermithidae: Nematoda), a Parasite of the Rice Stemborer, Tryporyza incertulas (Wlk.) (Pyralidae: Lepidoptera) in Malaysia

Hexamermis cathetospiculae n. sp. (Mermithidae: Nematoda), a parasite of the rice stemborer, Tryporyza incertulas (Wlk.), is described. This mermithid was observed to control the stemborer in Malaysia. It is distinguished from other members of the genus by the shape of the vagina, the nearly straight spicules, and the form of the amphids.

Sphaeronema sasseri n. sp. (Tylenchulidae), a Nematode Parasitic on Fraser Fir and Red Spruce

Sphaeronema sasseri n. sp. is described from Fraser fir and red spruce on Mount Mitchell in North Carolina. Females are distinguished from other species in the genus by body shape, occurrence of body annulations, stylet morphology, head shape, and by several morphometric characters. The nematodes occur in colonies surrounding the bases of lateral and feeder roots, and the infected tissues show a general breakdown of the cortex and bark. The roots appear to be severely damaged by high populations of nematodes. This parasite may be important in the etiology of the slow decline of spruce and fir that has occurred in recent years in the southern Appalachian Mountains.

Description of Meloidogyne pini n. sp., a Root-Knot Nematode Parasitic on Sand Pine (Pinus clausa), with Additional Notes on the Morphology of M. megatyla

Meloidogyne pini n. sp. is described from sand pine, Pinus clausa, in Georgia. The perineal pattern of the female has a large cuticular ridge surrounding a deeply recessed perivulval area. The lateral fields are marked by transverse striae. The female stylet is 14.6 mum long, and the knobs are small, rounded, and set off from the straight and narrow shaft. The excretory pore is near the level of the base of the stylet. The labial disc of the male is large, rounded, and fused with the crescent-shaped medial lips. The head region is smooth, the styler is 20.8 mum long, and the cone is more than twice as long as the shaft. The knobs are rounded and set off from the shaft. In the second-stage juvenile, the labial disc, medial lips, and lateral lips form one smooth, continuous, ovoid head cap. Mean juvenile length is 434 mum, stylet length is 12.8 mum, and tail length is 44.4 mum. M. pini n. sp. also parasitizes loblolly and slash pine. Additional morphological details of M. megatyla are presented.

Occurrence of Biotypes in Radopholus citrophilus

Two morphologically and karyotypically identical populations of the citrus burrowing nematode, Radopholus citrophilus, differed in their ability to damage and reproduce in roots of citrus rootstocks previously identified as either resistant or tolerant. These populations are considered to be biotypes, and their occurrence may explain the appearance of spreading decline symptoms in plantings of rootstocks previously considered resistant.

Cactodera eremica n. sp., Afenestrata africana (Luc et al., 1973) n. gen., n. comb., and an Emended Diagnosis of Sarisodera Wouts and Sher, 1971 (Heteroderidae)

Systematic contributions to Heteroderidae include description of Cactodera eremica n. sp., an emended diagnosis of Sarisodera Wouts and Sher, 1971, and proposal of a new genus and new combination, Afenestrata africana (synonym Sarisodera africana Luc et al., 1973). Cactodera eremica, from the roots of shadscale in Utah, most closely resembles Cactodera thornei (Golden and Raski, 1977) but differs by the presence of a finely striated cuticle, a fine surface pattern on eggs, a shorter female stylet, distance of the DGO from the stylet, vulval slit, and smaller diameter of circumfenestra, as well as a shorter tail in second-stage juveniles. The response of the host to C. eremica is similar to other Heterodera sensu lato including a large syncytium with wall ingrowths. The diagnosis of Sarisodera is emended to exclude cysts, which do not form in the type species, S. hydrophila. Afenestrata africana differs from S. hydrophila by the formation of cysts, the dorsal position of the anus in females, the shorter stylet, and a pore-like phasmid opening in second-stage juveniles. In addition, the lip pattern of males and juveniles is characterized by a greater degree of fusion of lip parts, the host response is a syncytium (versus a single uninucleate giant cell in S. hydrophila), and the cuticle is thinner and lacks a D layer. Unlike Heterodera, the cyst of Afenestrata lacks fenestrae.

Criconemella anastomoides n. sp. (Nematoda: Criconematina) from Pakistan

Criconemella anastomoides, described and illustrated herein, is characterized by the presence of regular anastomosis on the body, two zig zag lateral lines, stylet knobs sloping posteriorly, short stylet, and short body length.

Description of Pratylenchoides sheri n. sp. (Nematoda: Pratylenchidae)

Pratylenchoides sheri n. sp., a bisexual species from the Pacific coastal area of California, is described and illustrated. Its most distinctive characters are the esophageal glands slightly overlapping the intestine dorsally, the large ventrally slanting esophago-intestinal valve, the lack of labial sectors in the first lip annule, the presence of males, and apparently functional spermatheca. Pratylenchoides sheri is morphologically similar to P. magnicauda, but differs in length and labial conformation, its more anterior vulva, and the presence of males. Relationships of head and esophagus gland lobe characters of P. sheri are compared to other Pratylenchoides species.

Use of enzyme phenotypes for identification of meloidogyne species

Enzyme phenotypes were obtained for 291 populations from 16 species of Meloidogyne originating from 65 countries. Soluble proteins from macerates of individual egg-laying females were separated by electrophoresis in 0.7-mm-thick polyacrylamide gels. Enzymes investigated were nonspecific esterases, malate dehydrogenase, superoxide dismutase, and glutamate-oxaloacetate transaminase. Esterases were polymorphic and most useful in identification of major species. About 94% of the populations of M. hapla, 98% of M. incognita, and 100% of M. javanica could be identified to species on the basis of esterase phenotypes alone. About 84% of the populations of M. arenaria exhibited three distinct phenotypes. Two of them were highly species specific (accuracy of identification 98-100%). The third, and least prevalent, phenotype occurred also in two other species. Another 12 less common Meloidogyne species, of which only one or a few populations of each were studied, exhibited a variety of esterase phenotypes, some of which may prove to be species specific. Superoxide dismutase phenotypes similarly were helpful in the characterization of certain species; however, the same phenotype was often observed in more than one species. The remaining two enzymes, with few exceptions, proved to be less useful for identification of Meloidogyne species. Multienzyme phenotypes represented by two or more enzymes often offered biochemical profiles more valuable for definitive characterization of Meloidogyne species than single enzymes.

Dolichodorus miradvulvus n. sp. (Nematoda: Tylenchida) with a Key to Species

Dolichodorus miradvulvus n. sp. from Anubias nana Engler in Florida is described and illustrated. The female is characterized by deep grooves in the cuticle on the ventral surface just anterior and posterior to the vulva, and by transversely elongate pouches anterior and posterior to the vulva. Both sexes have a constricted area of the stylet shaft just anterior to the knobs, and on the male the intersection of the lateral field and bursa appear sclerotized.

Fungal Parasites of the Cereal Cyst Nematode Heterodera avenae in Southern Sweden

Fungal parasites of the cereal cyst nematode Heterodera avenae were isolated from four sites in southern Sweden. In all, 15 different fungi were isolated from different stages of the nematode life cycle. Among the egg parasites, Verticillium chlamydosporium was common in young cysts on roots, whereas an unidentified species of Verticillium (Verticillium sp. 1) was the dominating species in cysts from soil, especially if the soll had been stored for 8-12 months. V. chlamydosporium was frequently isolated from eggs in cysts from soil, when analyzed shortly after sampling. Verticillium sp. 1 is distinct from V. chlamydosporium because it does not produce dichtyo-chlamydospores in the aerial mycelium and because it grows at 6 C where V. chlamydosporium fails to grow. Paecilomyces lilacinus, Microdochium bolleyi, Cylindrocarpon sp., and several nonsporulating fungi were also isolated from eggs in cysts from soil. Between 10 and 20% of the eggs in cysts collected in the field were infected with fungi. In a pot test between < 1 and 29%, with a mean of 13%, of females on roots became infected, always by Nematophthora gynophila. Resting spores of N. gynophila extracted directly from field soil, collected at the four sites, varied from 3 to 49 spores/gram of air dried soil.

Gametogenesis and the Chromosomes of Meloidogyne nataliei: Not Typical of Other Root-knot Nematodes

Studies of oogenesis and spermatogenesis revealed that Meloidogyne nataliei is a diploid, amphimictic species with four (n), relatively large chromosomes, and possibly with an XX female symbol-XY male symbol mechanism of sex determination. It differs considerably from all other amphimictic, or meiotically parthenogenetic, species of Meloidogyne which have 13-18 smaller chromosomes and from Meloidogyne (Hypsoperine) spartinae which has seven. Consequently, the taxonomic position of M. nataliei needs to be re-evaluated. The chromosomes of M. nataliei and their behavior during gametogenesis resemble more closely chromosomes of the genus Heterodera than those of the genus Meloidogyne. This resemblance, however, may not imply a closer phyletic relationship of M. nataliei to heteroderid nematodes.

Population Dynamics and Description of Ptycholaimellus hibernus n. sp. (Nematoda: Chromadoridae)

Ptycholaimellus hibernus n. sp. from the muddy subtidal of North Inlet Estuary, Georgetown, South Carolina, is described and a key to the genus is provided. P. hibernus differs from all other species of Ptycholaimellus by the shape of the gubernaculum. Ptycholaimellus sp. 2 Hopper 1969 is synonymized with P. ponticus. The abundance of P. hibernus, measured over a 3-year period, is greatest from January to March, coinciding with minimal annual water temperatures (10-15 C). P. hibernus abundance was significantly (negatively) correlated with water temperature and (positively) with the depth of the anoxic sediment layer.

Reproductive Isolation and Taxonomic Differentiation of Romanomermis culicivorax Ross and Smith, 1976 and R. communensis Galloway and Brust, 1979

The infertility of hybrid progeny of Romanomermis communensis and R. culicivorax supports their retention as distinct species. Their taxonomic separation on the basis of morphometric data and possession of a cone-shaped spicule guide is rejected. However, differences in the enzyme patterns of peptidase and phosphoglucomutase and the restriction fragment length differences in repetitive genomic DNA provide sensitive diagnostic characters that confirm the differentiation into two species.

New and known species of pratylenchus filipjev, 1936 (nematoda: pratylenchidae) from haryana, India, with remarks on intraspecific variations

Two new monosexual and one bisexual species Pratylenchus Filipjev, 1936 collected from Haryana state of India are described and illustrated. The primary distinguishing features of these species are Pratylenchus microstylus n. sp.: L = 331-458 mum, spear = 11 or 12 mum; Pratylenchus cruciferus n. sp.: L = 648-793 mum, central core of lateral fields with oblique lines, hemizonid 2-8 annules anterior to excretory pore; Pratylenchus ekrami n. sp.: spear = 11-13 mum, spermatheca oblong, post vulval uterine sac with differentiated cells, tail with 26-40 annules, males abundant. Studies on intraspecific variations of P. cruciferus, P. ekrami, and P. coffeae (Zimmermann, 1898) Goodey, 1951 revealed that spear length and value of 'V' are the least variable characters. Body length and size of post vulval uterine sac varies to varying degrees in different species. Shape of median bulb in P. ekrami, number of incisures in P. coffeae, and tail shape in P. ekrami and P. coffeae exhibit the greatest amount of intraspecific variations. P. zeae Graham, 1936 and P. thornei Sher & Allen, 1953 are the other species collected during the present studies.

A New Gall-Forming Species of Anguina Scopoli, 1777 (Nemata: Anguinidae) on Bluegrass, Poa annua L., from the Coast of California

Anguina pacificae n. sp. is described and illustrated from stem galls on bluegrass, Poa annua L., from golf courses along coastal California. The females are characterized by constrictions in the anterior and posterior connections of the isthmus with the respective parts of the esophagus, the long multicellular columella, and the sharply pointed tail tip. Males are dorsally curved after death; body width is increased markedly after 13 annuli in both sexes, and the tail is conical and with an acute terminus.

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.).

Rhyssocolpus arcticus n. sp. (Nematoda: Nordiidae) from Ellesmere Island and a Redescription of Lindseyus costatus Ferris and Ferris, 1973 (Nematoda: Roqueidae) from Quebec, Canada

A new species of Rhyssocolpus from Ellesmere Island in the Canadian arctic is described and illustrated. Its distinctive features are the set off head and the extensively striated cuticle in the vulval area with well-developed vulval flaps. The male has small spindle-shaped sperm 4-5 mum in length, and the adanal supplement is separated from the anterior series of 7-11 supplements by a distinct gap. A key to the species of Rhyssocolpus is provided. Lindseyus costatus from the St. Lawrence River, Quebec, is also redescribed. Notable differences from the original description are the irregular muscle bands of the sinistrally spiraled esophageal sheath, smooth exocuticle, longer prerectum, shorter male tail, and longer spicules. New information on the esophageal gland nuclei and sperm size and shape is also provided.

Heterodera raskii n. sp. (Heteroderidae: Tylenchina), a Cyst Nematode on Grass, from Hyderabad, India

Heterodera raskii n. sp. is described and illustrated from specimens collected from roots of bulb grass, Cyperus bulbosus, in Hyderabad, India. The new species belongs to the 'goettingiana' group and differs from closely related H. cyperi by the elongate ovoid shaped cysts and females, greater fenestral length, width, vulval slit, and absence of egg sac. The stylet knob shape was round in second-stage juveniles and posteriorly sloping in females and males of H. raskii n. sp., while it was anteriorly directed in second-stage juveniles and spherical in females and males of H. cyperi.

Gastromermis kolleonis n. sp. (Nematoda: Mermithidae), a Parasite of Midges (Chironomus sp. Chironomidae) from Argentina

Gastromermis kolleonis n. sp. (Nematoda: Mermithidae) is described from the Arroyo Saldan River in Córdoba, Argentina. This species parasitizes midges of the genus Chironomus (Chironomidae: Diptera). It is distinguished from other members of the genus by the presence of six longitudinal chords, vulval flaps, degree of ventral displacement of the mouth, and size and shape of the spicule and amphids.

Protocylindrocorpus dendrophilus n. sp. (Nematoda: Cylindrocorpidae) Associated with Pine Wood Borings

Protocylindrocorpus dendrophilus n. sp. is described from xylem samples taken from beetle infested slash pine (Pinus elliottii Engelmann var. elliottii) in Central Louisiana. It is similar to P. goodeyi (Rühm) Paramonov, but differs by the possession of a protuberant and more posteriorly located vulva and in the position of the caudal papillae. Morphometrics of the male and female are presented.

Redescription of Xiphinema americanum Cobb, 1913 with Comments on Its Morphometric Variations

Xiphinema americanum is redescribed and illustrated from material collected from Arlington Cemetery, near Cobb's type locality (Falls Church, Virginia), Morphometric data showing variations within this species are given for three additional populations.

Meloidogyne microcephala n. sp. (Meloidogynidae), a Root-knot Nematode from Thailand

Meloidogyne microcephala n. sp. is described and illustrated from specimens obtained from tobacco (Nicotiana tabacum L.) in Thailand. The female perineal pattern usually has a low dorsal arch, coarse striae, and a series of small cuticular flaps around the tail terminus. The stylet of the female is 14.4 mum long, with large, square to rectangular stylet knobs, The distinctive male head region is narrow, small, and truncate with a low, flattened head cap. The stylet length is 20.6 mum, and the knobs are small, angular, and set off from the shaft. Mean length of second-stage juveniles is 457.5 mum, and stylet length is 9.3 mum. The tail tip in the juveniles is set off from the rest of the tail as a small finger-like projection. M. microcephala reproduces by mitotic parthenogenesis, and has a chromosome number of 2n = 36.

Hoplolaimoidea (nematoda: tylenchida) from the aleutian islands with descriptions of four new species

Four new species of hoplolaimoid nematodes (Merlinius adakensis, Pratylenchoides megalobatus, Pratylenchus pratensisobrinus, and Pratylenchus ventroprojectus) are described from Adak Island in the Aleutian chain. M. adakensis n. sp. is separated from other species by body length (0.96-1.3 mm), stylet length (32-36 mum), number of tail annules (49-68), and c' (3.1-4.1). P. megalobatus n. sp. differs from all known Pratylenchoides spp. by having a very long esophageal gland lobe (b' = 2.4-3.3, overlap 3-6 times the body width). P. pratensisobrinus n. sp. closely resembles P. pratensis (de Man) Filipjev, but has a longer stylet (15-17 mum), a longer tail (c = 12-15; c' = 2.8-3.7), and more tail annules (23-37). P. ventroprojectus n. sp. is distinguished by body length (392-475 mum), three lip annules, low and flattened cephalic capsule, and presence of terminal subventral projection. Pratylenchoides variabilis Sher, Helicotylenchus amplius Anderson &Eveleigh, and H. spitsbergensis Loof are also reported from Adak and Amchitka Islands.

Pterotylenchus cecidogenus n. gen., n. sp., a New Stem-gall Nematode Parasitizing Desmodium ovalifolium in Colombia

Pterotylenchus cecidogenus n. gen., n. sp. from stem-galls of Desmodium ovalifolium Wall. in Colombia is described and illustrated. The new genus belongs to Anguinidae and is related to Orrina Brzeski, 1980 but is unique in having large vulval flaps. P. cecidogenus has females with body 0.59-0.8 mm long, stylet 9-11 mum long, no median oesophageal bulb, a crustaformeria of 32-36 cells, a short post-vulval uterine sac, and a conical pointed tail.

Description of Males of Heterodera zeae

The male ofHeterodera zeae, the corn cyst nematode, is described and illustrated for the first time. Specimens were obtained from a culture originating from cysts collected in Kent County, Maryland, at the site of the first known infestation of H. zeae in the United States.

Taxonomic Limits of the Genus Nagelus (Thorne and Malek, 1968 Siddiqi, 1979 with a Description of Nagelus borealis n.sp. from Alaska

The genus Nagelus (Thorne and Malek, 1968) Siddiqi, 1979 is modified and a new species from Alaska is described. The combination of scanning electron microscopy and light microscopy permits the characterization of Nagelus spp. as having a broadly oval face pattern, no longitudinal striations on the lip region, deirids surrounded by six incisures, and an irregularly tapering tail with a large hyaline region. Nagelus leptus (Allen, 1955) Siddiqi, 1979, N. alpensis Doucet and Luc, 1981, N. camelliae (Kheiri, 1972) Siddiqi, 1979, N. jamelensis (Nesterov, 1973) Siddiqi, 1979, and N. obscurus (Allen, 1955) n. comb. are retained on this basis. Nagelus borealis n. sp. is characterized by a styler length of 30 mum or more, an irregularly scalloped perioral disc, and a proportionately larger basal bulb. Nagelus abalosi (Doucet, 1978) Doucet. 1980 and N. virginalis (Doucet, 1978) Doucet, 1980 are synonymized with N. leptus. Nine other species from Nagelus are transferred to Merlinius Siddiqi, 1970.

Parasitic Habits of Trophotylenchulus floridensis (Tylenchulidae) and its Taxonomic Relationship to Tylenchulus semipenetrans and Allied Species

Parasitism by Trophotylenchulus floridensis Raski, 1957 was studied on roots of sand pine (Pinus clausa [Chapm.] Vasey). Different life stages of the nematode were observed to be covered by dark, spherical, brittle, capsule-like structures which protruded from the root surface. The mature capsule enveloped a single sedentary female with a gelatinous matrix containing an average of 76 (44-117) eggs. The capsule was composed of a single layer of cells which appeared to be of plant origin. The anterior end of the nematode was embedded superficially in the root tissue where it created a feeding site comprised of a small number of discrete stelar parenchyma cells with dense cytoplasm and enlarged nuclei and nucleoli. The nematode also infected slash pine, Pinus elliottii, loblolly pine, P. taeda, red oak, Quercus falcata, post oak, Q. stellada, and sweet gum, Liquidambar styraciflua, in four different locations in central Florida. The taxonomic relationship between Tr. floridensis and Tylenchulus spp. is discussed. Based on differences in the tail and lip regions, position of the excretory pore, type of obesity and especially in the mode of plant parasitism, the genus Trophotylenchulus Raski, 1957 is upheld, and the transfer of Tylenchulus clavicaudatus Colbran, 1966, Ty. rnangenoti Luc, 1957, and Ty. obscurus Colbran, 1961 to Trophotylenchulus is proposed.

Morphological Characteristics of Hoplolaimus indicus Sher, 1963 in Canada, a Parasite of Wild Rice

Hoplolaimus indicus Sher, 1963 was found for the first time in North America as a parasite of wild rice. Supplemental descriptive data, supported by illustrations, are given which extend the known range of variability in this species. The body, stylet, and tail lengths were often greater than those in published reports from India, the esophageal gland overlap was consistently shorter than body width in most specimens, and the excretory pore and vulva were more posterior. Longitudinal striae of the basal head annule ranged from 6 to 20, number of tail atmules from 8 to 22, and the excretory pore extended at most 27 mum anterior or 22 mum posterior of the esophagointestinal valve. A taxonomic key is provided to facilitate the separation of the 13 species of Hoplolaimus having five or six esophageal gland nuclei.

Meloidogyne aquatilis n. sp (Nematoda:Meloidogynidae) from Spartina pectinata with a Key to the Canadian Species of Meloidogyne

A new root-knot nematode, Meloidogyne aquatilis n. sp., attacking the roots of Spartina pectinata Link growing in the Ottawa River is described and illustrated. Meloidogyne aquatilis is distinguished from M. graminis by the light brown body color and by the absence of perineal lateral fields in the female. The male differs by the shorter stylet and by the hemizonid being separated by 7-9 annules from the excretory pore. The second-stage juveniles are also recognized by the 7-9-annule gap between the hemizonid and excretory pore and by the shorter tail with a disc-like subterminal tail structure, lower b ratio value, and inflated rectum. A key to the root-knot nematode species of Canada based on females, males, and juveniles is provided. The type host of Dolichodera fluvialis Mulvey and Ebsary, 1980, Spartina pectinata Link, is reported for the first time.

Pungentus porosus n.sp. (Nematoda:Dorylaimoidea) from Canada with a Key to the Species of Pungentus

Pungentus porosus n. sp. is described and illustrated. The differential characters are a short odontostyle of 6-8 mum or slightly less than one head width, vulva at 44-50%, goblet-shaped amphids, presence of a prevulval uterine sac, and a hemispherical tail with a variable number of pores. Pungenlus sublatum, P. vesiculosus, P. orthocephalus, P. granosus, and P. parvus sensu Eroshenko are considered to be incertae sedis. A key is provided to the 21 valid species of Pungentus. The following species are new Canadian records: P. angulosus, P. clavatus, P. engradinensis, P. marietani, P. microdentatus, P. monohystera, P. obscurus, P. parvus, P. pungens and P. silvestris.

Rhizonema sequoiae n.gen. n.sp. from Coast Redwood Sequoia sempervirens (D.Don) Endl

Rhizonema sequoiae n.gen, u. sp. is described from the roots of Coast Redwood, Sequoia sempervirens (D. Don) Endl., growing near Lake Lagunitas, Marin County, California. Rhizonema females are annulated over their entire bodies, are wholly embedded in host tissue, and secrete an abundant amount of gel material. Mature females do not form a cyst. The vulva is located on a large posterior terminal cone, and the anus is on the dorsal vulval lip. Esophageal glands of the second-stage larvae fill more than half of the body cavity. Tails of the vermiform males are blunt, and a cloacal tubus is present.

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.

Description of Pararotylenchus belli n.sp. (Nematoda:Hoplolaimidae)

A new species of Pararotylenchus Baldwin &Bell, 1981 from the Pacific coastal area of California is described. Numerous females and juveniles were recovered, but no males were found. Pararotylenchus belli n.sp. is most similar to P. sphaerocephalus, but females of P. belli are shorter and have a shorter stylet and a hemispherical tail. Specimens from a cereal field in South Dakota were identified as P. colocaudatus.

Meloidogyne enterolobii n. sp. (Meloidogynidae), a Root-knot Nematode Parasitizing Pacara Earpod Tree in China

Meloidogyne enterolobii n. sp. is described and illustrated from roots of pacara earpod tree, Enterolobium contortisiliquum (Vell.) Morong, on Hainan Island in China. The perineal pattern of the female is usually oval shaped, the striae are fine to coarse, the dorsal arch is moderately high to high and usually rounded, and the phasmids are large. The stylet knobs in females are divided longitudinally by a groove so that each knob appears as two. The mean distance of the excretory pore to the anterior end in the female is 62.9 mum. Males have a large, rounded labial disc that fuses with the medial lips to form a dorso-ventrally elongate head cap. The labial disc is slightly elevated, and the medial lips are crescent shaped. The second-stage juvenile mean body length is 436.6 mum. The lateral lips are large and triangular in face view. The tail is 56.4 mum long and narrow with a broad, bluntly rounded tip. M. enterolobii n. sp reproduces well on E. contortisiliquum and causes severe damage. Other good hosts include cotton, resistant tobacco 'NC 95,' pepper, watermelon, and tomato.

Descriptions of Chitwoodius brasiliensis n.sp., Chitwoodius rusticulus n.sp., and Vancterlindia venata n.sp. (Dorylaimida: Tylencholaimidae: Vanderlindiinae)

Chitwoodius brasiliensis n.sp. is described from soil around plant roots in Vicosa, MG State, Brazil. It has a body 1.9 mm (1.6-2.5) long, odontostyle and odontophore 33 mum (31-37) and 34 mum (31-36) long, respectively, and males with spicules 59-61 mum long. Chitwoodius rusticulus n.sp. from Colombian rain forest differs from other species of the genus in having a weakly muscular anterior part of the oesophagus, a pore-like vulva, and an unsclerotized vagina. Vanderlindia venata n.sp. from lucerne soil in South Kilimanjaro, Tanzania, differs from the type and only other known species of its genus in having a smaller and less slender body (L = 3.34 mm [3.15-3.71], a = 50 [46-53]), odontostyle 2.3-2.5 times lip region width long, and stylet guiding ring located at 1.2-1.4 times lip region width from anterior end.

Nematode parasites and associates of Dendroctonus spp. and Trypodendron lineatum (Coleoptera: Scolytidae), with a description of Bursaphelenchus varicauda n.sp

Nematode parasites and associates of four bark beetle species in British Columbia were surveyed. Bursaphelenchus varicauda n.sp., Ektaphelenchus macrostylus, Panagrolaimus dentatus, and Cryptaphelenchus latus were found associated with Dendroctonus pseudotsugae. Parasitorhabditis obtusa was found in the gut and Contortylenchus reversus in the hemocoel of both D. pseudotsugae and D. rufipennis. The latter also had hemocoel infections of Sphaerulariopsis dendroetoni, which were not found concomitant with C. reversus infections. Contortylenchus brevicomi occurred in the hemocoel of D. brevicomis. The first report of a tylenchid larva parasitizing Trypodendron lineatum in North America is presented. Bursaphelenchus varicauda n.sp. was obtained from the gallery frass of D. pseudotsugae. It resembles B. corneolus and B. bestiolus but differs from the former species in female tail shape, the position of the excretory pore, spicule shape, and position of the male caudal papillae, and from the latter species in spicule shape and in the length of the esophagus and postuterine sac.

Cryphodera utahensis n. sp., (Heteroderidae), A New Species from Wild Rose in Utah

A new species of Cryphodera Colbran, 1966, parasitic on wild rose (Rosa sp. L.), is described from Utah, USA. Cryphodera utahensis n. sp. most closely resembles C. podocarpi (Wouts, 1973) Luc et al., 1978, but is distinct with respect to a number of characters including juveniles with a longer esophagus (206 versus 142 mum), shorter tail (47 versus 69 mun), and four rather than three incisures in the lateral field. Females of C. utahensis have a terminal protuberance which is more pronounced than in other species. Scanning electron microscope observations of the lip region of males indicate a labial disc surrounded by six lip sectors. However, the remainder of the lip region is comprised of irregularly-shaped plates; similar patterns with longitudinal striae apparently characterize males throughout the genus. The lip pattern of juveniles of C. utahensis n. sp. includes an oval labial disc surrounded by six lip sectors; transverse striae extend the height of the lip region without longitudinal striae. The type locality of C. utahensis confirms a broader distribution of the genus than was indicated for other species, which are limited to Australia (Queensland) and New Zealand.

Redescription of Heterodea zeae, the Corn Cyst Nematode, with SEM Observations

Heterodera zeae, the corn cyst nematode, is redescribed and illustrated with comparative details and measurements of females, cysts, and larvae from Maryland, USA; and India. Scanning electron micrographs o f specimens from the United States are also presented. Revised measurements for the larval stylet and new diadnostic characters, especially in the cyst cone, for H. zeae are given. The relationship of H. zeae to close species is discussed.

An illustrated key to the cyst-forming genera and species of heteroderidae in the Western hemisphere with species morphometrics and distribution

Diagnoses of the cyst-forming genera of Heteroderidae (viz., Heterodera, Sarisodera, Globodera, Punctodera, Cactodera, and Dolichodera) and distribution and morphometrics of the 34 known cyst species in the Western Hemisphere are presented along with an illustrated key for the identification of these genera and species. The key is based mainly on cysts and larvae, and important morphological and diagnostic features are extensively shown by LM and SEM illustrations. The genus Bidera is placed as a new synonym under the genus Heterodera.

Description of Distolabrellus veechi n. gen., n. sp. (Nematoda:Rhabditidae)

A new, monotypic genus and species in the subfamily Mesorhabditinae is described and illustrated. The primary character which separates the species and genus from all others in the Rhabditidae is a lip region with six set-off and well-separated liplets of two alternating shapes. Other diagnostic characters are transverse and fine longitudinal body striations, cuticular micropores, a prismatic prostom, well-developed esophageal collar, and three denticles on each metarhabdion. Males have a peloderan, open bursa bearing two pre- and seven post-anal bursal papillae, fused spicules over 50 mum long, and paired diverticulate cement glands associated with the vas deferens.

Description of Paktylenchus tuberosus gen. n., sp. n. (Nematoda: Tylenchinae)

Paktylenchus tuberosus gen.n., sp.n. is described and illustrated from soil around Solanum tuberosum from Kaghan Valley, Pakistan. Paktylenchus gen.n, can be distinguished from the most closely related genus, Agelenchus Andrassy, 1954, by the distinct longitudinal striae, three incisures in the lateral field, and absence of males. Paktylenchus tuberosus shows affinities to Coslenchus Siddiqi, 1978 but differs in having an oblique vagina-to-body axis and a prominent sunken vulva with vulval flaps. Four genera of the subfamily Tylenchinae are also discussed herein.

Description of Hoplolaimus magnistylus n. sp. (Nematoda: Hoplolaimidae)

Hoplolaimus magnistylus n. sp. is described and illustrated. It was found in soil around roots of soybean in Arkansas and Mississippi. It is similar to H. galeatus and H. concaudajuvencus. It differs from H. galeatus in all stages primarily by possession of a longer stylet. It differs from H. concaudajuvencus by the possession of rounded tails in second-stage juveniles vs. conically pointed tails with acute termini, having fewer subdivisions in female basal lip annules, and the greater distance from female anterior end to posterior end of esophageal lobes. Morphometrics and descriptions of second-, third-, and fourth-stage juveniles are given. A paratype female of H. sheri was examined and found to have six esophageal gland nuclei.

Description of Dolichodorus grandaspicatus n. sp. (Nematoda: Dolichodoridae)

Dolichodorus grandaspicatus n. sp., collected from soil about roots of a red maple (Acer rubrum L.) in a creek bottom near Ludwig. Johnson County, Arkansas, is described. It differs from two closely related species, D. marylandicus and D. heterocephalus, by the longer spike on the female tail, the lenght of the female tail, and the shape of the extrudable portion of the gubernaculum of the males. It further differs from D. marylandicus by having heavily sclerotized accessory pieces of the vuvla and from D. heterocephalus by having a shorter stylet.

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.

Morphological Comparison of Head Shape and Stylet Morphology of Second-stage Juveniles of Meloidogyne Species

Head shape and stylet morphology of second-stage juveniles of one population each of M. incognita, M. javanica, M. arenaria, and M. hapla were compared by light microscopy. Excised stylets of each species were also compared by scanning electron microscopy (SEM). Differences in head morphology were observed only between M. hapla and the other three species. In SEM, differences in stylet size, shape, and relative distance of the dorsal esophageal gland orifice to the base of the stylet were evident. Differences in stylet morphology between M. incognita and M. javanica could not he detected by light microscopy, but M. arenaria and M. hapla could be distinguished from each other and from the other two species. Head shape and styler morphology of second-stage juveniles are considered useful taxonomic characters.

Description of the Blueberry Root-knot Nematode, Meloidogyne carolinensis n. sp

Meloidogyne carolinensis n. sp. is described from cultivated highbush blueberry (cultivars derived from hybrids of Vaccinium corymbosum L. and V. lamarckii Camp) in North Carolina. The perineal pattern of the female has a large cuticular ridge that surrounds the perivulval area, and the excretory pore is near the level of the base of the stylet. The stylet is 15.9 mum long and the knobs gradually merge with the shaft. The head shape and stylet morphology of the male are quite variable. The typical head and four variants, as well as the typical stylet and two variants, are described. The labial disc, medial lips, and lateral lips of second-stage juveniles are fused and in the same contour. The head region is not annulated. Mean juvenile length is 463.7 mum, stylet length is 11.9 mum, and tail length is 42.5 mum.

Meloidogyne cruciani n. sp. a Root-knot Nematode from St. Croix (U.S. Virgin Islands) with Observations on Morphology of This and Two Other Species of the Genus

Meloidogyne cruciani n. sp. infecting tomato (Lycopersicon esculentum Mill.) in the U.S. Virgin Islands is described and illustrated. M. cruciani is distinguished from other species of the genus by having punctations around the anus of the female and by the second-stage juveniles possessing tri-lobed esophageal glands which are longer than most other species, with their posterier end at about 46.4% of the body length. The esophageal glands of the immature and adult females are contained in five separate lobes.

Criconematina (nematoda: tylenchida) from the aleutian islands

A new genus (Cerchnotocriconenta) and three new species (C. psephinum, Hemicycliophora amchitkaensis, and Paratylenchns amundseni) are described from Adak and Amchitka Islands in the Aleutian chain. The new genus differs from all other criconematid genera in having irregular, convex sculpturing consisting of small, oval plates on the anterior and posterior regions of each annule, with the mid-annular region minutely punctate or dentate. H. arnchitkaensis n. sp. resembles H. similis Thorne and H. zuckermani Brzeski, but has only one head annule, instead of two. P. antundseni n. sp., which has a stylet 17-19 mum long, is similar to P. tateae Wu &Townshend and P. labiosus Anderson &Kimpinski, but differs by the presence of males and the possession of conoid-truncate lip region, functional spermatheca, and long male tail (c = 8.5-9.5). Seriespinula seymouri Wu (Mehta &Raski), Nothocrieonema longulum (Gunhold) De Grisse &Loof, and Macroposthonia xenoplax (Raski) De Grisse &Loof are also reported from the islands.