Arrangement Of Male Caudal Papillae Research Articles

Schistonchus pumilae n. sp. isolated from syconia of a creeper fig, Ficus pumila L. from the Japanese warm temperate zone

Summary A Schistonchus species was isolated from the syconia of the creeping fig, Ficus pumila, collected from Miyazaki, Japan. The nematode was considered an undescribed species based on its typological characters, molecular profiles (near full length of small subunit and D3 expansion segment of large subunit of RNA) and phylogenetic status inferred from these two loci. The new species is characterised by the presence of flagellate sperm, spicule possessing small condylus, triangular rostrum with bluntly pointed tip and clear dorsal and ventral limbs, structure and arrangement of male caudal papillae, i.e., presence of papilliform P3 and P3a and small and gland opening-like P4 (glandpapillae), relatively short post-uterine sac and female tail forming elongate conoid. It is phylogenetically close to S. hirtus. However, the new species is distinguished from other nominal Schistonchus species by its female tail shape forming elongate conoid, the structure and arrangement of male caudal papillae and several other typological characters. In addition, the host fig of the nematode, F. pumila, is a creeper fig species belonging to subgenus Synoecia (section Rhizocladus; subsection Plagiostigma), from which no fig-associated nematode has been reported so far, i.e., the present study is the first report of Schistonchus (and other syconia-inhabiting nematodes) from the Ficus subgenus Synoecia.

Redescription of Ektaphelenchoides compsi Baujard, 1984 (Tylenchina: Aphelenchoididae) isolated from Pinus massoniana in Fujian Province, China

Summary Ektaphelenchoides compsi is redescribed morphologically with new molecular characterisation. It was isolated from a dead Pinus massoniana tree in Ningde City, Fujian Province, China. Detailed morphology of the spicule, female gonad, hemizonid position, arrangement of male caudal papillae and female tail terminus shape are documented. It is characterised by a lateral field with three lines (forming two bands), tripartite stylet 17.8 (17.0-19.4) μm long without basal thickenings, metacorpus rectangular with anterior 40% granular and posterior part weakly muscular, metacorpal valve slightly posterior to middle of metacorpus, excretory pore at level of nerve ring, vagina with thickened walls and strongly developed muscular bundles, vulval lips slightly protuberant, vulval flap absent, distal region of post-vulval uterine sac appearing as a weakly developed oogonia, anus and rectum indistinct, female posterior part (‘tail’) dorsally convex, conical, terminal region contracted into a bluntly pointed tip. The spicules are arcuate, 15.6 (14.3-16.3) μm along the chord, lamina smoothly curved to distal end, capitulum slightly concave, condylus well-developed with broadly rounded tip and slightly depressed at dorsal end, rostrum triangular with finely rounded tip, cucullus absent, and with seven caudal papillae present. The near full length 18S and 28S D2-D3 regions of rRNA genes sequences were characterised. The phylogenetic analyses revealed that the Fujian population of E. compsi grouped with the Zhejiang population of E. compsi, both being morphologically identical.

Species of Contracaecum Parasitizing the Magellanic Penguin Spheniscus Magellanicus (Spheniscidae) from the Argentinean Coast

Anisakid nematodes have a worldwide distribution and are associated with fishes, birds, and marine mammals from freshwater, brackish, and marine systems. The aims of this work are to report for the first time Contracaecum mirounga parasitizing the Magellanic penguin Spheniscus magellanicus, to report another Contracaecum species in the same host species, and to discuss the validity of Contracaeceum spheniscus. Several dead chicks, juveniles, and adults of S. magellanicus were collected along the Argentinean coast from 2002 to 2009. Nematodes were removed from digestive tracts and studied using both light and scanning electron microscopy. Nematode prevalences were 2.38% for C. mirounga and 12.5% for Contracaecum sp. Contracaecum mirounga was found in 1 penguin from Península Valdés, Chubut. This species is known as a specific parasite of marine mammals such as Pinnipedia, thereby suggesting that this nematode is not as specific as believed. Another species of Contracaecum sp. was found parasitizing 1 penguin from the Río de la Plata coast. It possessed an unusual interlabial morphology and arrangement of male caudal papillae. Despite the low prevalence, the distinct morphological features are convincing and support the presence of a new Contracaecum species. However, a formal description is not presented because sufficient male specimens are lacking. Finally, C. spheniscus is considered a junior synonym of Contracaecum pelagicum. Future molecular studies might be helpful to determine the real diversity of Contracaecum species parasitizing S. magellanicus considering the number of sibling species recognized among the anisakids.

Redescription of Bursaphelenchus parapinasteri (Tylenchina: Aphelenchoididae) isolated from Pinus thunbergii in China with a key to the hofmanni-group

Bursaphelenchus parapinasteriis redescribed morphologically and with new molecular characterisation. It was isolated from a deadPinus thunbergiion Changgang Mountain, Zhoushan Islands, Zhejiang Province, China. Detailed morphology of the spicule, female gonad, hemizonid position, arrangement of male caudal papillae, and female tail terminus shape are documented. The ITS-RFLP patterns and the ITS1/2, partial 28S D2-D3 and partial 18S gene sequences were characterised. The phylogenetic analyses revealed thatB. parapinasteribelongs to thehofmanni-groupsensuBraasch and is close toB. anamurius,B. hofmanni,B. mazandaranense,B. paracorneolus,B. pinasteriandB. ulmophilus. A diagnostic key to species of thehofmanni-group is presented.

Description of Bursaphelenchus piceae sp. n. (Nematoda: Parasitaphelenchinae) from larval galleries of the six-toothed spruce bark beetle, Pityogenes chalcographus (L.) (Coleoptera: Curculionidae: Scolytinae), in Norway spruce, Picea abies (L.) Karsten

Bursaphelenchus piceae sp. n. is described from the bark of Norway spruce, Picea abies. Adults and propagative juveniles of the nematode are found in larval galleries of the six-toothed spruce bark beetle, Pityogenes chalcographus, while its dauer juveniles aggregate in Malpighian tubules of older larvae, pupae and adult beetles. The new species is characterised by the body length of 719 (530-945) μm in female and 632 (474-808) μm in male, its moderately slender body (a = 41.4 (35.4-50.2) and 42.6 (35.1-47.2) in female and male, respectively), and small spicules (16.0 (14.0-18.3) μm along arc and 13.7 (12.2-15.5) μm along chord). The extended anterior vulval lip in female, lateral fields with four incisures, long post-uterine sac extending for 67-91% of vulva-anus distance, and number (7) and arrangement of male caudal papillae suggest that B. piceae sp. n. is closely related to the xylophilus-group yet it differs by the relatively small, claw-like spicules with no cucullus at the tip. The close relation of B. piceae sp. n. to the xylophilus-group has been confirmed by DNA sequencing and phylogenetic analysis. Morphologically B. piceae sp. n. most closely resembles B. tokyoensis and B. fagi but can be separated from both by the unique shape of the spicules. The taxonomic separation of the new species is also confirmed by the unique molecular profile of the ITS region (ITS-RFLP). The presence of dauer juveniles of B. piceae sp. n. in Malpighian tubules of adult P. chalcographus may lead to extensive damage to this organ as shown by local expansion of the tubule basement membrane and degradation of its cellular epithelium. Detailed phylogenetic analysis revealed that B. piceae sp. n. together with five other bark beetle-associated Bursaphelenchus species, namely B. trypophloei, B. masseyi, B. tiliae, B. tokyoensis and B. fagi, constitutes a small phylogenetic clade that is most closely located to, but separate from, the xylophilus-group.

Subulura halli (Ascaridida: Subuluridae) from the endangered great bustard Otis tarda Linnaeus (Aves: Gruiformes) in China

Subulurid nematodes identified as Subulura halli Barreto, 1918 were collected from the endangered bird Otis tarda Linnaeus (Gruiformes: Otididae) in China. A detailed redescription of the hitherto poorly known species is presented using both light and, for the first time, scanning electron microscopy. Previously unreported and erroneous morphological features of taxonomic significance are revealed. This species can be readily distinguished from its congeners by the relatively long oesophagus (1.47-1.92 mm long, representing 10.6-16.9% of body length), the number and arrangement of male caudal papillae (11 pairs in total, arranged as five pairs of precloacal and six pairs of postcloacal papillae), the equal length of spicules (1.35-1.52 mm long, representing 10.7-13.7% of body length) and the presence of a small medioventral, precloacal papilla in the male.

Bursaphelenchus fagi sp. n. (Nematoda: Parasitaphelenchidae), an insect-pathogenic nematode in the Malpighian tubules of the bark beetle, Taphrorychus bicolor (Herbst.) (Coleoptera: Curculionidae, Scolytinae), in European beech, Fagus silvatica L.

Bursaphelenchus fagisp. n. is described from the bark of European beech,Fagus silvatica. All propagative stages of the nematode are numerous in larval galleries of the beech bark beetle,Taphrorychus bicolor, while dauer juveniles aggregate in Malpighian tubules of adult beetles. The new species is characterised by the body length of 871 (763-1110) μm in female and 852 (718-992) μm in male, very slender body (a = 56.8 (50.4-67.1) and 64.5 (56.5-73.8) in female and male, respectively), and spicules 15.2 (14.0-17.0) μm long. The extended anterior vulval lip in female, lateral fields with four incisures, and number (7) and arrangement of male caudal papillae may indicate thatB. fagisp. n. is closely related to thexylophilusgroup. It differs from this group by the relatively small, claw-like spicules with narrow capitulum, indistinct condylus in almost continuous line with dorsal lamina, and lack of distinct cucullus at the spicule tip. The close relation ofB. fagisp. n. with thexylophilusgroup has been confirmed by DNA sequencing and phylogenetic analysis of the 28S rDNA region.Bursaphelenchus fagisp. n. most closely resemblesB. tokyoensisandB. idius, but can be separated by differences in the arrangement of the male caudal papillae, a unique feature for each species. The taxonomic separation of the new species is also confirmed by the unique molecular profile of the ITS region (ITS-RFLP). The mass presence of dauer juveniles ofB. fagisp. n. in Malpighian tubules of adultT. bicolorleads to degradation of the tubule cellular epithelium and local expansion of its basement membrane. These changes clearly indicate direct pathogenicity of the nematode to its vector insect. In laboratory rearing,B. fagisp. n. can grow and reproduce onBotryotinia fuckelianacultures.

Bursaphelenchus tiliae sp. n. (Nematoda: Parasitaphelenchidae), a nematode associate of the bark beetle Ernoporus tiliae (Panz.) (Coleoptera: Curculionidae, Scolytinae), in small-leaved lime, Tilia cordata Mill.

Bursaphelenchus tiliae sp. n. is described from the bark of dead branches of the small-leaved lime, Tilia cordata, infested with the lime bark beetle, Ernoporus tiliae. The nematode adults and propagative juveniles were present in larval galleries, while dispersal dauer juveniles colonised the Malpighian tubules of adult beetles. Bursaphelenchus tiliae sp. n. is characterised by the body length of 664 (568-817) μm in female and 622 (515-754) μm in male, moderately slender body (a = 41.0 (34.7-47.9) and 43.1 (37.8-51.9) in female and male, respectively), and spicules 20.0 (18.1-21.8) μm long. The extended anterior vulval lip in female, lateral fields with four incisures, long post-uterine sac, and number (7) and arrangement of male caudal papillae, may indicate that B. tiliae sp. n. is closely related to the xylophilus group. It differs from this group by smaller, arcuate spicules with relatively short rostrum, narrow capitulum (5.2-6.9 μm), and indistinct condylus in an almost continuous line with dorsal lamina. Distal third of spicule dorsal contour is usually almost straight. The spicules have a distinct, disk-like cucullus at the terminus. The status of the new species is confirmed by the unique molecular profile of the ITS region (ITS-RFLP) and its close relation to the xylophilus group by DNA sequencing and phylogenetic analysis of the 28S rDNA region. The presence of B. tiliae sp. n. dauer juveniles in Malpighian tubules of their vector bark beetle, E. tiliae, caused limited pathogenicity expressed as a local expansion of the tubule basement membrane and partial degradation of the cellular epithelium.

Further studies on Contracaecum spasskii Mozgovoi, 1950 and C. rudolphii Hartwich, 1964 (sensu lato) (Ascaridida: Anisakidae) from piscivorous birds in China

Contracaecum spasskii Mozgovoi, 1950, collected from the great crested grebe Podiceps cristatus (Linnaeus) (Podicipediformes: Podicipedidae), is redescribed using both light and, for the first time, scanning electron microscopy. Contracaecum spasskii differs from its congeners by having marked transverse cuticular annulations, the length of the oesophagus and spicules, the ratio between the intestinal caecum and the ventricular appendix, the number and arrangement of male caudal papillae, and especially by the particular morphology of the lips and interlabia. Some previously unreported morphological features of C. spasskii are also revealed and others corrected. Contracaecum rudolphii Hartwich, 1964 (sensu lato) is also redescribed based on the specimens collected from the great cormorant Phalacrocorax carbo sinensis (Blumenbach) (Pelecaniformes: Phalacrocoracidae) from China. Based on the geographical perspective, the present Chinese material may represent the species C. rudolphii B.

Bursaphelenchus masseyi sp. n. (Nematoda: Parasitaphelenchinae) – a nematode associate of the bark beetle, Trypophloeus populi Hopkins (Coleoptera: Curculionidae: Scolytinae), in aspen, Populus tremuloides Michx. affected by sudden aspen decline in Colorado

Bursaphelenchus masseyi sp. n. is described from trunks of unhealthy trembling aspen, Populus tremuloides, affected by sudden aspen decline (SAD) in Colorado, USA. All propagative stages of the nematode were present in larval galleries of a bark beetle, Trypophloeus populi. The dauer juveniles occupy the haemocoel of older larvae, pupae and adult beetles. The characteristic morphology of the male spicules with small but distinct cucullus, extended anterior vulval lip in female, lateral fields with four incisures, and number and arrangement of male caudal papillae, indicate that B. masseyi sp. n. is closely related to the xylophilus group. This relation has been confirmed by DNA sequencing and phylogenetic analysis of the 28S rDNA region. The new species is characterised by the body length of 958 (765-1203) μm in female and 874 (691-1122) μm in male, moderately slender body (a = 38.2 (33.5-41.1) and 38.0 (33.1-44.1) in female and male, respectively), and spicules 29.2 (26.2-34.7) μm long with a small cucullus (1.3-1.5 μm in diam.) at their tips. Bursaphelenchus masseyi sp. n. can be separated from other species in the xylophilus group by the morphology of spicules which have a short capitulum and unique rostrum that is pointed somewhat anteriorly, relatively thick vulval flap, which is straight, parallel to the body long axis and bent towards the body wall at its distal end, and other morphological and morphometric characters. The new species most closely resembles B. trypophloei, but differs by the morphology of spicules (short but distinct condylus vs condylus in a continuous line with dorsal lamina, and smaller cucullus). The taxonomic separation of the new species is also confirmed by the unique molecular profile of the ITS region (ITS-RFLP). Diallelic cross-breeding in vitro revealed also that B. masseyi sp. n. and B. trypophloei are reproductively incompatible. The new species showed poor ability to develop and reproduce on Botrytis cinerea cultures, although it grew vigorously on laboratory cultures of Polish and Colorado isolates of Cytospora chrysosperma, the fungus naturally associated with galleries of the nematode vector, T. populi.

Morphological and genetic characterization of Hysterothylacium zhoushanensis sp. nov. (Ascaridida: Anisakidae) from the flatfish Pseudorhombus oligodon (Bleeker) (Pleuronectiformes: Paralichthyidae) in the East China Sea

Hysterothylacium zhoushanensis sp. nov. collected from the intestine of the flatfish Pseudorhombus oligodon (Bleeker) (Pleuronectiformes: Paralichthyidae) in the East China Sea is described and illustrated by light and scanning electron microscopy. The new species can be easily distinguished from its congeners by the presence of remarkable lateral alae, the very short intestinal caecum, the unusually long ventricular appendix (ratio of intestinal caecum to ventricular appendix 1:8.74-23.8), the short spicules (0.58-0.81 mm long, representing 1.70-2.08 % of body length) and the number and arrangement of male caudal papillae (35-42 pairs in total, arranged as 26-32 pairs of precloacal, two pairs of paracloacal and six to eight pairs of postcloacal). In addition, the adults and the putative third-stage larvae identified morphologically of the new species are characterised by sequencing and analysing the internal transcribed spacer (ITS) of the ribosomal DNA. The result reveals that they are homogeneous genetically, and all belong to the same species. Molecular analysis by comparing the ITS gene of H. zhoushanensis sp. nov. with these species of Hysterothylacium available in GenBank also seem to support the validity of the new species based on the morphological observation.

Goezia nankingensis Hsü, 1933 (Nematoda: Raphidascarididae) from the critically endangered Chinese paddlefish Psephurus gladius (Martens) (Acipenseriformes: Polyodontidae)

Goeziine nematodes identified as Goezia nankingensis Hsü, 1933 were collected from the Chinese paddlefish Psephurus gladius (Martens) (Acipenseriformes: Polyodontidae), a critically endangered freshwater fish, from the Yangtze River in China. Their examination, using light microscopy and, for the first time, scanning electron microscopy, revealed some erroneous and previously unreported morphological features, necessitating the redescription of this poorly known species. Goezia nankingensis is easily distinguished from its congeners by the morphology and arrangement of its cuticular spines, the short intestinal caecum and long ventricular appendix (ratio of intestinal caecum to ventricular appendix 1:10.0-18.3), the short spicules (0.34-0.49 mm long, representing 6.09-10.1% of the body length), the number and arrangement of male caudal papillae [14-16 pairs in total, approximately arranged: precloacal 7-10 pairs, paracloacal 2 pairs and postcloacal 4-6 pairs (one pair double)], and the presence of a particular medio-ventral, precloacal papilla in the male.

Morphological and molecular identification of Hysterothylacium longilabrum sp. nov. (Nematoda: Anisakidae) and larvae of different stages from marine fishes in the South China Sea

A new ascaridoid nematode Hysterothylacium longilabrum sp. nov. collected from the intestine and stomach of the marine fishes Siganus fuscescens (Houttuyn) and Siganus canaliculatus (Park) (Perciformes: Siganidae) in the South China Sea is described and illustrated. The new species differs from its congeners by the unusually long lips, the very short intestinal caecum and relatively long ventricular appendix (ratio of intestinal caecum to ventricular appendix, 1:2.38-5.50), the long spicules (1.96-3.28 mm long, representing 7.42-11.4% of the body length), the number and arrangement of male caudal papillae [38-43 pairs in total, arranged as: 31-34 pairs precloacal, 1 pair of paracloacal and 4-6 pairs postcloacal (the second or fourth pair double)] and the presence of a particular medioventral precloacal papilla in the male. Molecular analyses by sequencing and comparing the internal transcribed spacer (ITS) of the ribosomal DNA of H. longilabrum sp. nov. with the closely related nematode sequences seem to support the validity of the new species based on the morphological observation. In addition, the third- and fourth-stage larvae of the new species are also exactly identified and described by analysing and comparing the ITS sequence with the adult, and the result is a substantial step toward elucidating its life cycle.

Mawsonascaris parva sp. nov. (Nematoda: Ascaridida) from the Arabian whipray Himantura randalli Last, Manjaji-Matsumoto et Moore (Rajiformes: Dasyatidae) off the coast of Iraq

Mawsonascaris parva sp. nov. collected from the Arabian whipray Himantura randalli Last, Manjaji-Matsumoto et Moore (Rajiformes: Dasyatidae) off the coast of Iraq is described and illustrated using light and scanning electron microscopy. The new species differs from its congeners by its small body size (8.11-18.2 mm long), the absence of an intestinal caecum, the slightly unequal spicules (left and right spicule 1.08-2.50 mm and 0.98-2.01 mm long, respectively, representing 12.1-13.7% and 10.1-12.1% of body length), the number and arrangement of male caudal papillae (13-14 pairs in total, arranged as: 7-8 pairs of precloacal, 1 pair of double paracloacal and 5 pairs of postcloacal) and the presence of a single, median precloacal papilla. Thus, a total of six species of Mawsonascaris are now known and this is the first species of this genus recorded from species of Himantura.

New host and geographical records and morphological details for Echinuria skrjabiniensis (Nematoda, Acuariidae) from shorebirds in Argentina

AbstractThe acuarioid nematode Echinuria skrjabiniensis Efimov in Skryabin, Sobolev et Ivashkin, 1965 was found in Calidris bairdii and C. fuscicollis (Aves, Scolopacidae) examined from several locations from Patagonia, Argentina. These constitute new host records as well as the first record of this parasite species in South America. Using both light and scanning electron microscopies, new morphological details are provided, including the description of the left spicule and the number and the arrangement of male caudal papillae. The taxonomic history of the species is summarized, corroborating its correct spelling and valid name.

Bursaphelenchus trypophloei sp. n. (Nematoda: Parasitaphelenchinae) – an associate of the bark beetle, Trypophloeus asperatus (Gyll.) (Coleoptera: Curculionidae, Scolytinae), in aspen, Populus tremula L.

Abstract Bursaphelenchus trypophloei sp. n. is described from weakened and dead twigs of living or recently fallen aspen trees, Populus tremula, in Poland. All propagative stages of the nematode were present in larval galleries of a bark beetle, Trypophloeus asperatus, and its dauer juveniles could be found in the haemocoel of older larvae, pupae and adult beetles. Characteristic morphology of the male spicules with distinct cucullus, extended anterior vulval lip, lateral fields with four incisures, and number and arrangement of male caudal papillae indicate that B. trypophloei sp. n. is closely related to the xylophilus group. This relation has been further confirmed by DNA sequencing and phylogenetic analysis of the 28S and ITS-1 rDNA region. Bursaphelenchus trypophloei sp. n. can be separated from other species in the xylophilus group by the morphology of spicules which have a shorter capitulum and unique rostrum which is pointed somewhat anteriorly, relatively thick vulval flap, which is straight, parallel to the body long axis or bent towards the body wall at its distal end, and other morphological and morphometric characters, i.e., shape of female tail, position of excretory pore at or posterior to nerve ring, spicule length of 25.7 (23.1-28.0) μm (as measured along arc) and shape, moderate length, i.e., L = 702 (603-946) μm in females and L = 679 (543-828) μm in males, and slender body (a = 39.2 (33.0-45.2) and 40.9 (32.0-46.4) in female and male, respectively). The taxonomic separation of the new species is also confirmed by the unique molecular profile of the ITS region (ITS-RFLP). Full reproductive incompatibility of B. trypophloei sp. n. with B. xylophilus, B. mucronatus, B. fraudulentus, B. populi and B. doui has been demonstrated in in vitro diallelic cross-breeding. The newly described nematode revealed limited ability to develop and reproduce on Botrytis cinerea cultures although it produced large populations on laboratory cultures of Cytospora chrysosperma – a fungus naturally associated with galleries of the nematode vector, T. asperatus.

A New Cucullanid Species (Nematoda) from Ageneiosus ucayalensis Castelnau, 1855 (Pisces: Auchenipteridae) from Pará, Brazil

Cucullanus ageneiosus n. sp. (Nematoda: Cucullanidae) is described from the intestine of the Ageneiosus ucayalensis , from the Guajará Bay, Belém, Pará, Brazil. The new species is characterized mainly by arrangement of male caudal papillae, and the position of lateral phasmids immediately posterior of 10th papillae, markedly short and unequal spicules, a precloacal sucker, and the presence of an unpaired median papilla just of the anterior cloacal lip.

Description of Bursaphelenchus populi sp. n. (Nematoda: Parasitaphelenchidae), a new member of the xylophilus group from aspen, Populus tremula L., in Europe

AbstractBursaphelenchus populi sp. n. is described from dying and dead aspen trees, Populus tremula, in Poland. The nematode was found in trees infested with a long-horn beetle, Saperda perforata, and is vectored in the insect haemocoel. The characteristic morphology of male spicules, extended anterior vulval lip, lateral fields with four incisures, and number and arrangement of male caudal papillae, place B. populi sp. n. in the xylophilus group. Bursaphelenchus populi sp. n. can be separated from all other species in that group by the distinctive vulval flap, which is always bent with its distal half sunken in a conspicuous, sharp depression posterior to the vulva, and other morphological and morphometric characters, i.e., female tail shape, excretory pore position, spicule length (32.1 (25.7-37.0) μm (as measured along arc) and shape, and a relatively long (i.e., L,= 1020 (909-1111) μm in females), and L = 850 (756-1055) μm in males), and slender body (a = 45.4 (40.2-52.4) and 42.0 (36.1-49.3) in female and male, respectively). The status of the new species is confirmed by the unique molecular profile of the ITS region (ITS-RFLP). DNA sequencing and phylogenetic analysis of 28S rDNA region placed the new species close to B. fraudulentus in the xylophilus group. In vitro cross-breeding of the new nematode with B. xylophilus, B. mucronatus, B. fraudulentus and B. doui revealed full reproductive incompatibility between these species. In laboratory experiments on 2-year-old seedlings B. populi sp. n. was specific to aspen. It did not develop on pine or oak and reproduced only in weakened or dead aspen seedlings. No pathogenicity to the tree host or vector insect was observed. In Botrytis cinerea PDA cultures, body dimensions were significantly altered in both sexes and female tail morphology differed when compared to individuals extracted from aspen wood.

Diplogastrellus metamasius n. sp. (Rhabditida: Diplogastridae) isolated from Metamasius hemipterus (L.) (Coleoptera: Dryophthoridae) in southern Florida and Costa Rica

AbstractDiplogastrellus metamasius n. sp. (Rhabditidae) was cultured from dauer juveniles recovered during dissections of the West Indian sugarcane weevil, Metamasius hemipterus (Coleoptera: Dryophthoridae), from southern Florida and Costa Rica. Morphological studies of these two isolates with light microscopy and SEM revealed many typological differences between it and the closest putative relative. Based upon molecular and mating studies, the two isolates are conspecific and are described herein as Diplogastrellus metamasius n. sp. Diplogastrellus metamasius n. sp. is characterised by stomatal structure, i.e., cheilostom with thin adradial cuticular flaps, anterior region of gymnostom ring strongly cuticularised and refractile, stegostom forming a structure resembling a 'glottoid' apparatus and possessing a movable, flap-like, dorsal tooth with small ventral ridges, oblong (elongated) median bulb in both sexes, single gonad with short (less than one vulva body diam.) postuterine sac, well developed ovary reflexed posteriorly beyond the vulva, tapered to filiform tail in both sexes, relatively large gubernaculum in males (with arcuate anterior part and pointed distal part in lateral view) and arrangement of the nine pairs of male genital papillae, especially the position of first two pairs which are located far anterior to the cloacal slit. Because of the many possibilities for homoplasy in the morphological characters possessed by the new species and described species in the 'sister' genera of Butlerius, i.e., the arrangement of male caudal papillae, and Paroigolaimella, i.e., the arrangement of cheilostomatal flaps, molecular analysis of more members of these putative clades is necessary before unambiguous generic placement of this new species is possible.

Three nematode species from elasmobranchs off New Caledonia

Nematode specimens of three species, Terranova scoliodontis (Baylis, 1931) (Ascaridida, Anisakidae), Echinocephalus sinensis Ko, 1975 and E. overstreeti Deardorff & Ko, 1983 (both Spirurida, Gnathostomatidae) were collected from the tiger shark Galeocerdo cuvier, the ray Aetobatus cf. narinari and the blotched fantail ray Taeniura meyeni, respectively, from the coastal waters of New Caledonia, South Pacific. Their examination, including scanning electron microscopy (SEM), made it possible to obtain some new data on their morphology, e.g. in relation to the number and arrangement of male caudal papillae in T. scoliodontis and both Echinocephalus spp., the presence of ventral cuticular ornamentations in T. scoliodontis and the number of transverse spines on the cephalic bulb in Echinocephalus spp. All these species are reported for the first time from New Caledonian waters and G. cuvier is a new host species for T. scoliodontis. SEM examination of the fourth-stage larvae of E. overstreeti from the type-host showed the presence of anterior dorsal and ventral groups of minute spines on the cephalic bulb to be an important taxonomic feature for the interspecific distinction of Echinocephalus larvae and questions previous data on the occurrence of E. overstreeti larvae in many elasmobranch fishes and molluscs in Australian waters.