Description of Thecavermiculatus carolynae n. sp. (Nematoda: Ataloderinae)

Thecavermiculatus carolynae n. sp. from the Pacific coastal area of California is described from female, male, and juvenile (J2) specimens reared on Festuca megalura Nutt. in the greenhouse. Differences between females of T. carolynae and those of its closest relative, T. gracililancea Robbins, 1978, include shorter stylet, shorter length, and lesser length of the vulval slit. Of these two species, males have been found only for T. carolynae. The habitats of the two species are vastly different: T. gracililancea has been found only in shallow clay soil near hilltops in an area subject to high summer temperatures where the soil becomes brick-like during the summer; T. carolynae has been found only in deep sandy soil of a creek bottom subject to cool summer temperatures where the soil remains moist.     

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.     

Host-Parasite Relationships of Atalodera spp. (Heteroderidae)

Atalodera ucri, Wouts and Sher, 1971, and A. lonicerae, (Wouts, 1973) Luc et al., 1978, induce similar multinucleate syncytia in roots of golden bush and honeysuckle, respectively. The syncytium is initiated in the cortex; as it expands, it includes several partially delimited syncytial units and distorts vascular tissue. Outer walls of the syncytium are relatively smooth and thickest near the feeding site of the nematode; inner walls are interrupted by perforations which enlarge as syncytial units increase in size. The cytoplasm of the syncytium is granular and includes numerous plastids, mitochondria, vacuoles, Golgi, and a complex network of membranes. Nuclei are greatly enlarged and amoeboid in shape. Although more than one nucleus sometimes occur in a given syncytial unit, no mitotic activity was observed. Syncytia induced by species of Atalodera chiefly differ from those of Heterodera sensu lato by the absence of cell wall ingrowths; wall ingrowths increase solute transport and characterize transfer cells. In syncytia of Atalodera spp., a high incidence of pits and pit fields in walls adjacent to vasctdar elements suggests that in this case plasmodesmata provide the pathway for increased entry of sohttes. The formation of a syncytium by species of Atalodera and Heterodera sensu lato, but a single uninucleate giant cell by Sarisodera and Hylonema, indicates a pattern of host responses that may be useful, with other characters, for phylogenetic inference for Heteroderidae.     

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.     

Descriptions of Deladenus albizicus n. sp. and D. processus n. sp. (Nematoda: Hexatylina) from Haryana,India

Two different nematodes were isolated from the bark of Albizia lebbeck trees; one from insect infested and another from noninfested, healthy tree. Based on the biological, morphological, and molecular evidences, the nematodes are described as Deladenus albizicus n. sp. and D. processus n. sp. (Nematoda: Hexatylina). Deladenus albizicus n. sp., isolated from insect-infested tree, multiplied on the fungus Nigrospora oryzae. Myceliophagous females of this nematode reproduced by parthenogenesis and spermathecae were indistinct. Infective females, readily produced in the cultures, are dorsally curved. Only one type of males containing small-sized sperms in their genital tracts were produced in the culture. Myceliophagous females: L = 0.75 to 1.71 mm, a = 32.3 to 50.8, b = 9.3 to 11.2, b’ = 5.2 to 7.3, c = 27.2 to 35.6, V = 91.0 to 93.3, c’ = 2.0 to 2.9, stylet = 11 to 12 µm, excretory pore in the region of median pharyngeal bulb, 43 to 47 µm anterior to hemizonid. Deladenus processus n. sp., isolated from bark of healthy A. lebbeck tree, was cultured on Alternaria alternata. Myceliophagous females reproduced by amphimixis and their spermathecae contained rounded sperms. Infective females were never produced, even in old cultures. Myceliophagous females: L = 0.76 to 0.99 mm, a = 34 to 49, b = 13.3 to 17.7, b’ = 3.8 to 5.8, c = 19.6 to 22.8, V = 92.2 to 93.5, c’ = 2.7 to 3.5, stylet = 6 to 7 µm, excretory pore in the proximity of hemizonid, tail conoid, tapering from both sides to a long pointed central process. It is proposed to classify Deladenus species in three groups: durus, siricidicola, and laricis groups based on female and spermatogonia dimorphism, mode of reproduction, and insect parasitism.     

Fine Structure of Body Wall Cuticle of Females of Eight Genera of Heteroderidae

Body wall cuticle of adult females of eight genera within the Heteroderidae was examined by transmission electron microscopy for comparison with previously studied species within the family. Cuticle structure was used to test some current hypotheses of phylogeny of Heteroderidae and to evaluate intrageneric variability in cuticle layering. Verutus, Rhizonema, and Meloidodera possess striated cuticle surfaces and have the simplest layering, suggesting that striations have not necessarily arisen repeatedly in Heteroderidae through convergent or parallel evolution. Atalodera and Thecavermiculatus possess similar cuticles with derived characteristics, strengthening the hypothesis that the two genera are sister groups. Similarly, the cuticle of Cactodera resembles the specialized cuticle of Globodera and Punctodera in having a basal layer (D) and a surface layer infused with electron-dense substance. Heterodera betulae has a unique cuticle in which the thickest layer (C) is infiltrated with an electron-dense matrix. Little intrageneric difference was found between cuticles of two species of Meloidodera or between two species of Atalodera. However, Atalodera ucri has a basal layer (E) not found in other Heteroderidae. The most striking intrageneric variation in cuticle structure was observed between the thin three-layered cuticle of Sarisodera africana and the much thicker four-layered cuticle of Sarisodera hydrophila; results do not support monophyly of Sarisodera.     

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.     

Tylenchulus graminis n. sp. and T. palustris n. sp. (Tylenchulidae), from Native Flora of Florida,with Notes on T. semipenetrans and T. furcus

Tylenchulus graminis n. sp. and T. palustris n. sp. are described and illustrated from broomsedge (Andropogon virginicus L.) and pop ash (Fraxinus caroliniana Mill.), respectively. T. graminis resembles T. furcus in having a distinct anus, but T. graminis second-stage juveniles (J2) do not have a bifid tail. T. semipenetrans does not have a perceptible anus. The mature female of T. graminis has a mucronate pointed terminus while T. semipenetrans has a smooth and round terminus. T. graminis males have wider stylet knobs and basal bulb and a longer tail than T. semipenetrans males. T. graminis J2 have a longer posterior body portion (without large fat globules) than T. semipenetrans J2. T. palustris resembles T. semipenetrans in having an undetectable anus but differs by the short and conoid mature female postvulval section. The male of T. palustris has larger stylet knobs and basal bulb than those of T. semipenetrans and a bluntly rounded tail terminus, which is tapered in T. semipenetrans. T. palustris differs from T. furcus and T. graminis in having an undetectable anus, by the conoid postvulval section of mature females, by the shorter and rounded tail of males, and the shorter J2 posterior body section without large fat globules. T. graminis and T. palustris are parasites of indigenous flora of Florida.     

Description and SEM Observations of Meloidogyne chitwoodi n. sp. (Meloidogynidae), a Root-knot Nematode on Potato in the Pacific Northwest

Meloidogyne chitwoodi n. sp. is described and illustrated from potato (Solanum tuberosum) originally collected from Quincy, Washington, USA. This new species resembles M. hapla, but its perineal pattern is basically round to oval with distinctive and broken, curled, or twisted striae around and above the anal area. The vulva is in a sunken area devoid of striae. Vesicles or vesicle-like structures are present in the median bulb of females. The larva tail, being short and blunt with a hyaline tail terminal having little or no taper to its rounded terminus, is distinctively different from M. hapla. SEM observations revealed the nature of the perineal pattern and details of the head of larvae and males, and showed the spicules to have dentate tips ventrally. Hosts for M. chitwoodi n. sp. include potato, tomato, corn, and wheat but not strawberry, pepper, or peanut. The latter three crops are excellent hosts for M. hapla. The known distribntion of this new root-knot species presently involves certain areas of Idaho, Washington, and Oregon. The common name "Columbia root-knot nematode" is proposed for M. chitwoodi n. sp.     

Aphelenchoides microstylus n. sp. and Seinura onondagensis n. sp. (Nemata: Aphelenchina) from New York

Aphelenchoides microstylus n. sp. and Seinura onondagensis n. sp., a nematode predator, are described from dead Scots pine (Pinus sylvestris L.) in Onondaga County, New York. Females of A. microstylus are 370 to 485 µm long. The body is slender and tapers posteriorly to an amucronate, pointed terminus. The head is continuous with the body, and lips bear a stylet guide. Diagnostic characters of females are three incisures in the lateral field, a short stylet (6-7.5 µm) with small basal knobs, a single row of oocytes, and a long postuterine sac (25-50 µm). Males are characterized by small spicules (10-11µm); two pairs of post-anal, subventral papillae; and a single row of spermatocytes. A bursa and gubernaculum are absent. Seinura onondagensis females are characterized by a body of moderate length (475-595 µm), finely annulated cuticle, and a slightly set-off head. Diagnostic characters are four incisures in the lateral field, long stylet without basal knobs (17-22 µm), single row of oocytes, and presence of a postuterine sac (14-38 µm). Males are unknown. The monospecific genus Indaphelenchus is proposed as a synonym of Seinura, and S. siddiqii n. comb. is proposed for the only species, I. siddiqii.     

The life cycle and host specificity of Psychodiella sergenti n. sp. and Ps. tobbi n. sp. (Protozoa: Apicomplexa) in sand flies Phlebotomus sergenti and Ph. tobbi (Diptera: Psychodidae)

Two new gregarines in the recently erected genus Psychodiella (formerly Ascogregarina), Psychodiella sergenti n. sp. and Psychodiella tobbi n. sp., are described based on morphology and life cycle observations conducted on larvae and adults of their natural hosts, the sand flies Phlebotomus sergenti and Phlebotomus tobbi, respectively. The phylogenetic analyses inferred from small subunit ribosomal DNA (SSU rDNA) sequences indicate the monophyly of newly described species with Psychodiella chagasi. Ps. sergenti n. sp. and Ps. tobbi n. sp. significantly differ from each other in the life cycle and in the size of life stages. The sexual development of Ps. sergenti n. sp. (syzygy, formation of gametocysts and oocysts) takes place exclusively in blood-fed Ph. sergenti females, while the sexual development of Ps. tobbi n. sp. takes place also in males and unfed females of Ph. tobbi. The susceptibility of Phlebotomus perniciosus, Phlebotomus papatasi, Ph. sergenti, Ph. tobbi, and Phlebotomus arabicus to both gregarines was examined by exposing 1st instar larvae to parasite oocysts. High host specificity was observed, as both gregarines were able to fully develop and complete regularly the life cycle only in their natural hosts. Both gregarines are considered as serious pathogens in laboratory-reared colonies of Old World sand flies.     

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.     

Batwanema gen. n. and Chokwenema gen. n. (Oxyurida,?Hystrignathidae), new nematode genera?as parasites of Passalidae (Coleoptera) from the Democratic Republic of Congo

Two new genera and species parasitizing passalid beetles from the Democratic Republic of Congo are described. Batwanema congo gen. n. et sp. n. is characterized by having females with the cervical cuticle armed with scale-like projections, arranged initially in rows of eight elements that gradually divide and form pointed spines toward the end of the spiny region, two cephalic annuli, clavate procorpus and genital tract monodelphic-prodelphic. Two Malagasian species of Artigasia Christie, 1934 were placed in this genus as B. latum (Van Waerebeke, 1973) comb. n. and B. annulatum (Van Waerebeke, 1973) comb. n. Chokwenema lepidophorum gen. n. et sp. n. is characterized by having females with the cervical cuticle armed with scale-like projections, arranged initially in rows of eight elements (similar to Batwanema) that divide gradually, forming spines; a single cephalic annule cone-like, truncated, moderately inflated; procorpus sub-cylindrical and genital tract didelphic-amphidelphic.     

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.     

Three New Species of Heteroderoidea (Nematoda) from the Aleutian Islands

Three new species of Heteroderoidea are described from Adak and Amchitka Islands in the Aleutian chain. Second-stage juveniles of Thecavermiculatus crassicrustata, n. sp., differ from those of T. gracililancea Robbins by having longer stylets (40-45 μm vs 19-22 μm). The female of T. crassicrustata has a longer neck, a more posterior excretory pore, and lacks a posterior protuberance. Meloidodera eurytyla, n. sp., differs from other Meloidodera spp. in that second-stage juveniles have longer stylets (32-35 μm) and much more massive stylet knobs, while males have a longitudinally striated basal head annule. Meloidogyne subarctica, n. sp., can be separated from other Meloidogyne spp. by combinations of the following characteristics: perineal pattern with large oval areas in the tail region devoid of striae, arch with few unbroken striae; female excretory pore 1.5-2.5 × the stylet length from the anterior end; haploid chromosome number = 18; the spermatheca filled with sperm; stylet length of second-stage juveniles 13.5-15.4 μm.     

Trichodorus petrusalberti n. sp. (Nematoda: Trichodoridae) from Rice with Additional Notes on the Morphology of T. sanniae and T. rinae

A new species in the family Trichodoridae, from the rhizosphere of rice (Oryza sativa L.) in Northern Natal, South Africa, is described and illustrated. Trichodorus petrusalberti n. sp. resembles T. taylori De Waele, Mancini, Roca, and Lamberti, 1982, T. hooperi Loof, 1973, and T. complexus Rahman, Jairajpuri, and Ahmad, 1985, from which it is distinguished by the shape of the spicules. It is distinguished from the former two species by the nonthickened terminal cuticle in the males and by the shape and sclerotization of the vulval-vaginal region in lateral view in the females. Additional morphological details are given for T. sanniae Vermeulen and Heyns, 1985 and T. rinae Vermeulen and Heyns, 1985.     

New mites Terraphagus antipodus gen. n., sp. n. and Neohyadesia minor sp. n. (Acarina: Astigmata: Algophagidae) from islands of the Southern Ocean

Mites are a diverse and important component in the soils of the Southern Ocean islands, but for many groups, their taxonomy and biogeography is little studied. This paper reports the Algophagidae, a poorly known family, from the New Zealand region for the first time. The study used soil samples from seabird burrows, brackish algal wrack samples and a museum collection to recover specimens. Terraphagus antipodus gen. n., sp. n. is described from grey petrel Procellaria cinerea burrow soil on the Antipodes Islands, New Zealand. The axillary organ is confined to the dorsum; the epigynal apodeme ends are fused with the ends of coxal apodeme II; seta 2a and ω2 are absent, and the famulus is bilobed. Males have the sternum fused to coxal apodemes II; the tarsal setae of legs I, III and IV of the male are modified for mate guarding. The short stout legs I and II end in huge spines in females as e, d, q, s, wa and hT. From brackish algal wrack, Lake Forsyth/Wairewa, Canterbury, New Zealand, another algophagid Neohyadesia minor sp. n. is described and illustrated. The new species is the smallest known algophagid. A neohyadesid collected in 1961 is newly reported here from Eudyptes sp. penguin rookery mud from North Head, Macquarie Island. These records further extend the known microhabitats of the family to the allochthonous marine seabird nutrient flow into islands in the New Zealand region and make Neohyadesia Hughes and Goodman, 1969 present in all Southern Ocean provinces.     

Effect of Age on Body Wall Cuticle Morphology of Heterodera schachtii Schmidt females

Fine structure of the body wall cuticle of Heterodera schachtii is compared with respect to age and body region of the female. The cuticle is more complex than previously reported. In newly molted females only layers A, B, and C are present, but 4 weeks after the final molt a thin D layer is present between the midbody and base of the cone. This D layer is absent in the cone of H. schachtii, regardless of age. As females age, an additional layer E is produced and includes zones E₁ and E₂. Zone El apparently is unique to H. schachtii, whereas E₂ is likely to be homologous with a similar layer in Atalodera. In the cone of old females (ca. 8 weeks after the final molt) of H. schachtii, the two zones become irregular in shape and comprise bullae. The presence of a thin D layer in Heterodera strengthens the previous hypothesis of a single ancestor of cyst nematodes.