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.     

Helicotylenchus stylocercus n. sp. and Rotylenchus phaliurus n. sp. (Nematoda: Hoplolaimidae) from Costa Rica

Two new species of plant-parasitic nematodes from Costa Rica are described. Helicotygenchus styloeercus n. sp., from soil around roots of banana at Coto, is distinguished hy the female tail, which bears a large pillarlike ventral projection. Rotylenchus phaliurus n. sp., from soil artmnd roots of Dioscoroea sp. at Sixaola, differs from R. caudaphasmidius in having the conus equal to or more than half the spear length, and large terminal annules on the female tail.     

Macroposthonia sicula n. sp. (Nematoda: Criconematidae), a Parasite of Olive Trees in Sicily

Macroposthonia sicula n.sp. collected from rhizosphere and roots of olive (Olea europaea L.) at Kamarina, Sicily, Italy, is described and illustrated. It is distinguished from the related species (M. sphaerocephala and M. maskaka) by the longer styler and the characteristic narrowing postvulval portion of the body.     

Description of Tylenchorhynchus qasimii sp. n. with a New Report of T. kegasawai from Pakistan

A new stunt nematode, from soil around the roots of coconut (Cocos nucifera L.) and rice (Oryza sativa L.) from Karachi, Pakistan, is described and illustrated as Tylenchorhynchus qasimii n. sp. This new species is characterized by having females with 3–4 head annules, anteriorly directed stylet knobs, absence of post anal extension, presence of rounded sperm filled spermatheca and conoid to bluntly rounded hemispherical tail terminus. Males are common. Also included is the record of T. kegasawai from around the roots of rice (O. sativa L.), a new report from Sindh, Pakistan.     

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] μm), strongly sclerotized excretory duct opening posterior to nerve ring, and broadly rounded caudal alae of males.     

Description of Pratylenchoides camachoi n. sp. (Tylenchida: Pratylenchidae) from Spain

Pratylenchoides camachoi n. sp. from rosemary (Rosmarinus officinalis L.) in Sierra De Cazorla in southeastern Spain is described and illustrated. Pratylenchoides camachoi n. sp. is a bisexual species characterized by a cylindroid, sometimes clavate-shaped, male tail with a uniquely shaped smooth, rounded terminus. Females are characterized by a short esophageal overlap and six lines in the lateral field, which reduce to four in the tail region; not areolated except outer bands in the esophageal and tail regions.     

Meloidogyne lusitanica n. sp. (Nematoda: Meloidogynidae), a Root-knot Nematode Parasitizing Olive Tree (Olea europaea L.)

A root-knot nematode from Portugal, Meloidogyne lusitanica n. sp., is described and illustrated from specimens obtained from olive trees (Olea europaea L.). Females of the new species have a characteristic perineal pattern with medium to high trapezoidal dorsal arch with distinct punctuations in the tail terminus area. The excretory pore is located posterior to the stylet, about 1.5-2.5 stylet lengths from the anterior end. The stylet is 17.1 μm long with pear-shaped knobs. Males have a rounded, posteriorly sloping head cap and head region not annulated. The robust stylet, 24.5 μ long, has large, elongate knobs. Mean length of the second-stage juveniles is 449.5 μm, stylet length 14.2 μm, and tail length 44.1 μm. Scanning electron microscope observations provide further details of perineal patterns and head and stylet morphology of females, males, and second-stage juveniles. Meloidogyne lusitanica n. sp. did not reproduce on any of the differential hosts used to separate the four most common Meloidogyne species. The common name "olive root-knot nematode" is proposed for M. lusitanica n. sp.     

Description and Larval Heteromorphism of Hoplolaimus concaudajuvencus,n. sp. (Nematoda: Hoplolain-lidae)

Hoplolaimus concaudajuvencus n. sp., of the genus Hoplolaimus Daday, 1905, characterized by larval heteromorphism, is described and illustrated as recovered from ryegrass/bermudagrass golf green turf in Florida. Females and males are closely related to H. galeatus (Cobb, 1913) Thorne, 1935, but have longer stylets with more definitely tulip-shaped stylet knobs which anteriorly tend to close upon the stylet shaft more than in H. galeatus. First and second-stage larvae have a conically-pointed tail unlike any known species of the genus. Subsequent stages, including females, have rounded tails essentially similar to other species of the genus and males possess the typical hopolaimid tail and bursa. The first molt was found to occur within the egg.     

Heterodera achilleae n. sp. (Nematoda: Heteroderidae) from Yarrow in Yugoslavia

Heterodera achilleae n. sp., a member of the H. rostochiensis group, is described and illustrated from roots of yarrow, Achillea millefolium L. in Sarajevo, Yugoslavia. This new, round-cyst species differs from closely related species especially as follows: (1) from H. leptonepia, by having stouter larvae (a = 21), with longer styler (25 μ), and with outlet of dorsal esophageal gland averaging 5.7 μ from base o f styler; (2) from H. millefolii, in having excretory pore at base of neck and small, straight vulval slit of 5 μ; (3) from H. rostochiensis, in having a B/A ratio (Granek''s ratio) of 1.6 ; (4) from H. tabacum, by longer female stylet, two annules on female head, and males with outlet of dorsal esophageal gland further back (5.7 μ). In addition, H. achilleae n. sp. differs from the latter three species in having prominent longitudinal striae on the anterior half, or more, of cysts and females.     

Description of Tylenchorhynchus thermophilus n. sp. (Nematoda: Tylenchina) from Saltgrass in Death Valley,California

A stunt nematode, Tylenchorhynchus thermophilus n. sp., is described and illustrated from soil collected around roots of saltgrass (Distichlis spicata) in Death Valley, California. It is distinguished from the similar species, T. ewingi, T. mexicanus, and T. mashoodi, in having a longer female body, longer tail with more annules, and larger phasmids. Physical and chemical analysis of soil from saltgrass roots showed it to consist of 71% sand and possess high salinity (salt content of 0.51%) and a pH of 9.3.     

Soil Properties and Olive Cultivar Determine the Structure and Diversity of Plant-Parasitic Nematode Communities Infesting Olive Orchards Soils in Southern Spain

This work has studied for the first time the structure and diversity of plant-parasitic nematodes (PPNs) infesting olive orchard soils in a wide-region in Spain that included 92 locations. It aims at determining which agronomical or environmental factors associated to the olive orchards are the main drivers of the PPNs community structure and diversity. Classical morphological and morphometric identification methods were used to determine the frequency and densities of PPNs. Thirteen families, 34 genera and 77 species of PPNs were identified. The highest diversity was found in Helicotylenchus genus, with six species previously reported in Spain and with H. oleae being a first report. Neodolichorhynchus microphasmis and Diptenchus sp., Diphtherophora sp., and Discotylenchus sp., usually considered fungal feeders, were also reported for the first time associated to olive rhizosphere. PPNs abundance ranged from 66 to 16,288 individuals/500-cm³ of soil with Helicotylenchus digonicus being the most prevalent species, followed by Filenchus sp., Merlinius brevidens and Xiphinema pachtaicum. Nematode abundance and diversity indexes were influenced by olive cultivar, and orchard and soil management practices; while olive variety and soil texture were the main factors driving PPN community composition. Soil physicochemical properties and climatic characteristics most strongly associated to the PPN community composition included pH, sand content and exchangeable K, and maximum and minimum average temperature of the sampled locations. Our data suggests that there is a high diversity of PPNs associated to olive in Southern Spain that can exert different damage to olive roots depending on the olive variety and their abundance. Further analysis to determine the resistance levels of most common olive varieties to the prevalent PPNs in Spain will help to choose the most appropriate ones for the establishment of new plantations. This choice will take into consideration the specific soils and environments where those olive varieties will be established.     

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.     

Heterodera canadensis n. sp. (Nematoda: Heteroderidae) from Spike-Rush (Eleocharis acicularis (L.) R. &S.) in Quebec,Canada

Heterodera canadensis n. sp. is described and illustrated from the roots of spike-rush, Eleocharis acicularis (L.) R. &S., in Deschenes, Quebec. This new abullate species is related to Heterodera graminophila Golden and Birchfield, 1972, but differs significantly in cyst shape, cone top structures, body length of the second-stage larva (520-600 μm, vs. 380-400 for H. graminophila) and tail length (110-120 μm, vs. 57-67 for H. graminophila). A taxonomic key based on cyst and second-stage larva characters is provided for identification of the fifteen species in the Heterodera goettingiana group.     

Description of Dolichodorus cobbi n. sp. (Nematoda: Dolichodoridae) with Description of Dolichodorus cobbi n. sp. (Nematoda: Dolichodoridae) with Morphometrics and Lectotype Designation of D. heterocephalus Cobb, 1914

Dolichodorus cobbi n. sp. is described and illustrated from soil around roots of "woods" on the Stanley Farm, Scott County, Arkansas. This species is distinguishable from others of the genus by its short tail projection. It is most closely related to D. marylandicus but differs in having a short tail projection, longer stylet, greater body length, larger c value, and also in position of excretory pore. A limited number of Cobb''s original specimens and drawings of D. heterocephalus were examined. A lectotype and paralectotype were designated to establish the taxonomic base for the genus. Cobb''s original modified labeled drawing of D. heterocephalus is also included. Morphometric data on D. heterocephalus from the type locality and several other populations are given. Some variations in female tail shape, body length, and stylet length were noted.     

Nacobbodera chitwoodi,n. gen., n. sp., (Nacobbidae:Nematoda) on Douglas Fir in Oregon

Nacobbodera chitwoodi, n. gen., n. sp., representing Nacobboderinae n. subfam, in the Nacobbidae, is described and illustrated from roots of Douglas fir, Pseudotsuga menziesii near Florence Oregon. This new species, having characters common to Nacobbidae, Heteroderidae, and Meloidogynidae, appears to represent a connecting link between these three families of the Heteroderoidea. Especially, a distinct tail on swollen adult females, vermiform shape of juvenile females, and the shape and sclerotization of the head of the various stages, indicate a Nacobbidae relationship. Certain other characteristics present in this new species are of the Heteroderidae and Meloidogynidae type as follows: Gross shape of adult female in posterior half of body, two ovaries, anterior position of excretory pore as in Meloidogyne females, absence of a bursa, and development of male within a sausage-shaped cuticle as in root-knot and cyst nematodes.     

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.     

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.     

Description of Dorylaimoides punctatus n. sp. and Paractinolaimus acutus n. sp. (Nematoda: Dorylaimida) from Korea

Soil samples collected from Taebak Changkunbong and Undal mountains of Kyungbuk Province, yielded two new species of the order Dorylaimida which are described and illustrated below. Dorylaimoides punctatus n. sp. (Nematoda: Dorylaimida) is 1.2–1.4 mm long; b = 5.9–6.9; c = 14.6–17.7; odontostyle 7.3–8.5 μm; spicules 33.5–36.5 μm; ventromedian supplements 5–6 and is characterized by having zig-zag lines on body cuticle, continuous lip region, elongate conoid tail and comes close to Dorylaimoides micoletzkyi (De Man, 1921) Thorne & Swanger, 1936 and Dorylaimoides leptus Husain & Khan, 1968. Paractinolaimus acutus n. sp. (Nematoda: Dorylaimida) is 2.1–2.4 mm long; b = 4.3–4.9; c = 10–12; odontostyle 25–27 μm and characterized by having continuous lip region, longitudinally oval vulva and long filiform tail with acute tip and comes close to Parctinolaimus aruprus Khan et al., 1994 and Parctinolaimus baldus Thorne, 1967.     

Meloidogyne mayaguensis n. sp. (Meloidogynidae), a Root-knot Nematode from Puerto Rico

Meloidogyne mayaguensis n. sp. is described and illustrated from specimens obtained from galled roots of eggplant, Solanum melongena L., from Puerto Rico. The perineal pattern of females is round to ovoid with fine, widely spaced striae. It has occasional breaks of striation laterally and a circular tail tip area lacking striae. The stylet, 15.8 μm long, has reniform knobs that merge gradually with the stylet shaft. Males have a high, rectangular, smooth head region, not set off from the body contour. The labial disc is continuous with the medial lips which do not slope posteriorly. The styler, 22.9 μm long, has large rounded backward sloping knobs; the shaft is of uneven diameter. Mean body length of second-stage juveniles is 453.6 μm. The truncate head region is not annulated, and the rounded, slightly raised labial disc and the crescentic medial lips form dumbbell-shaped lip structures. The stylet, 11.6 μm long, has rounded, posteriorly sloping knobs. The slender tail, 54.4 μm long, gradually tapers to a bluntly pointed tip. Tomato, tobacco, pepper, and watermelon are good hosts; cotton and peanut are not hosts. M. mayaguensis n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of 2n = 44-45. The enzyme patterns are unique among Meloidogyne species.     

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.