A revised polytomous key for the identification of species of the genus Xiphinema Cobb, 1913 (Nematoda: Longidoridae) with exclusion of the X. americanum-group: Supplement 1

Codes are given for eleven Xiphinema species described since the new polytomous key (Loof & Luc, 1990) was submitted plus one species described earlier but which had not come to the authors' notice. Differences from related species are given. X. ilyasi Ahmad & Baqri, 1987 is considered a junior synonym of X. ensiculiferum (Cobb, 1893) Thorne, 1937. X. clavatum Heyns, 1965 is transferred from Group 8 to Group 5. The authors agree that X. attorodorum Luc, 1961 is a junior synonym of X. parasetariae Luc, 1958.     

A revised polytomous key for the identification of species of the genus Xiphinema Cobb, 1913 (Nematoda: Longidoridae) with exclusion of the X. americanum-group

The species of the genus Xiphinema Cobb, 1913 are listed and their current status is indicated. A revised polytomous key to the 172 valid species (excluding the X. americanum-group) is presented. Because of the very large number of species the key is split into eight groups on the basis of development of the anterior female genital branch, uterine differentiation and tail shape. In accordance with the opinion of Cohn & Sher (1972) X. vulgare Tarjan, 1964 is considered a synonym of X. setariae Luc, 1968. X. cubense Razzhivin, 1973 is placed in species inquirendae. Longidorella chappuisi (Schneider, 1935) is transferred to Xiphinema and its possible identity with X. hygrophilum Southey & Luc, 1974 is discussed.     

A Key and Diagnostic Compendium to the Species of the Genus Tylenchorhynchus Cobb, 1913 (Nematoda: Belonolaimidae)

An identification key to 111 species of Tylenchorhynchus is given. Tylenchorhynchus is defined as containing only those species with four incisures in the lateral field. A compendium providing the most important diagnostic characters for use in identification of species is included as a supplement to the key. Some species in a related but unnecessary genus were placed in the genus Tylenchorhynchus, based on morphological structures and logical groupings of the species. Bitylenchus iphilus is transferred to Tylenchorhynchus. The diagnosis of Tylenchorhynchus is emended, and a list of all the valid species of the genus is given. The characters most useful for separating species are the stylet length, shape of lip region, number of lip annules, shape of tail and tail terminus, number of tail annules, and position of vulva (V%). As defined in the paper, the genus currently is composed of 111 valid species.     

A new species of Xiphinema americanum group (Nematoda: Longidoridae) from Iran,with additional data on three known species

Systematic Parasitology - One new and three known species of the genus Xiphinema from the rhizosphere of fruit trees and rose shrubs in East Azarbaijan province, Iran, are presented based on the...     

Chromadoridae (Chromadorida: Nematoda) from the Indian Ocean: Difficulties in morphological identification of Actinonema Cobb, 1920 and Rhips Cobb, 1920.

The diagnostic characteristics of ActinonemaCobb, 1920 and Rhips Cobb, 1920 are reviewed andtheir importance for genera diagnosis assessed. Threespecies of Actinonema and one species of Rhips are described. Actinonema longicaudatumSteiner, 1918 is characterised by short (2–3 µmlong) anterior sensilla, cylindrical body with arather narrow anterior end, lateral alae with invertedV-patterns, wide (70–75 of cbd) double amphids andaccessory pieces composed of only the telamon which isbroad anteriorly and tapers on the posterior and along tail. Actinonema paraceltica ischaracterised by long (4–5 µm) anterior sensilla,large amphids (83–88% of cbd), lateraldifferentiation of V pattern on each annule andaccessory pieces with telamons that have shortextensions. Actinonema smolae sp. n. ischaracterised by long and thin body, large amphidslocated close to the anterior end and six solid cones.Rhips reginae n.sp. is characterised by sixsolid cones, large (90% cbd) amphids, lateraldifferentiation of two longitudinal rows of dots anddouble jointed spicules.     

Molecular phylogeny of the nematode genus Longidorus (Nematoda: Longidoridae) with description of three new species

The phylum Nematoda includes the genus Longidorus, a remarkable group of invertebrates that are polyphagous root‐ectoparasites of many plants including various agricultural crops and trees. Damage is caused by direct feeding on root cells as well as by transmitting nepoviruses. Species discrimination in Longidorus is complicated by phenotypic plasticity (intraspecific variability and minor interspecific differences) leading to potential misidentification. We conducted nematode surveys in cultivated and natural environments in southern Spain that detected 11 species of Longidorus. We developed a comparative study amongst these related species by considering morphological and morphometric features together with molecular data from nuclear ribosomal RNA genes [D2‐D3 expansion segments of large ribosomal subunit (28S), internal transcribed spacer 1 (ITS1), and partial small ribosomal subunit (18S)]. The results of our molecular and phylogenetic analyses confirmed the morphological hypotheses and allowed the delimitation and discrimination of three new species of the genus, described herein as Longidorus baeticus sp. nov. , Longidorus oleae sp. nov. , and Longidorus andalusicus sp. nov. , and eight known species (Longidorus alvegus, Longidorus crataegi, Longidorus fasciatus, Longidorus intermedius, Longidorus iuglandis, Longidorus magnus, Longidorus rubi, and Longidorus vineacola). Phylogenetic analyses of Longidorus spp. based on the three molecular markers resulted in a general consensus of these species grouping, as lineages were maintained for the majority of species (i.e. species with a conoid‐rounded lip region, amphidial fovea asymmetrically bilobed, female tail bluntly rounded), but not in some others (i.e. positions of L. crataegi, L. intermedius, and L. rubi were quite variable). To date, this is the most complete phylogenetic analysis for Longidorus and Paralongidorus species, with the highest number of species included. No correspondence between phylogenetic trees and morphological characters was found for ribosomal markers, with the exception of amphidial shape. Thus, polyphasic identification, based on integration of molecular analysis with morphology, is a tool beyond doubt in Longidorus identification. © 2013 The Linnean Society of London     

New species of Metepsilonema (Nemata,Epsilonematidae) from the Channel and the Mediterranean Sea with a polytomous key for the identification of species of the genus

Four new species of Metepsilonema are described from sublittoral stations from the Channel and are mainly characterized: M. volutum sp.nov. by the large body size for the genus up to 460 m, 118–121 well overlapping annuli and wide multispiral amphids; M. amphidoxum sp.nov. by 127–133 shortly overlapping annuli and sexual dimorphism in amphid size; M. comptum sp.nov. by 133–140 non-overlapping annuli, anteriormost annuli provided with a wide lumen and borders ornamented with ridges and M. corrugatum sp.nov. by 108–111 overlapping annuli provided with ridges). Additional information is provided for M. callosum together with a discussion on intraspecific variability. A new species of Metepsilonema spec. based on females only, is described but remain unnamed. M. comptum sp.nov. and M. corrugatum sp.nov. are also occurring in the Mediterranean Sea. A polytomous key to species level is presented.     

Calcaridorylaimus castaneae sp. n. (Nematoda,Dorylaimidae) from Bulgaria with an identification key to the species of the genus

An unknown species belonging to the genusCalcaridorylaimus Andrássy, 1986 was collected from the litter of broadleaf forests dominated by Castanea sativa Mill. and mixed with Quercus daleshampii Ten. and Fagus sylvatica L. on Belasitsa Mountain, south-western Bulgaria. Calcaridorylaimus castaneae sp. n. is characterised by its long body (1.4–2.1 mm), lip region practically not offset, vulva transverse, short odontostyle (14.5–16 μm) and tail (75.5–110.5 μm, c=14.7–23.6; c’=2.9–4.4) in females and 38–46 μm long spicules with small spur before their distant end in males. It is most similar to C. andrassyi Ahmad & Shaheen, 2004, but differs in having transverse vs pore-like vulva and shorter spicules (38–46 μm vs 52–57 μm). An identification key to the species of the genus Calcaridorylaimus is proposed. Phylogenetic analyses were performed on 18S and D2-D3 expansion domains of 28S rRNA genes by Neighbor-Joining, Maximum Likelihood and Bayesian Inference methods. The phylograms inferred from 18S sequences showed closest relationships of the new species with some species belonging to the genus Mesodorylaimus. However, insufficient molecular data for members of both genera do not allow the phylogenetic relationships of Calcaridorylaimus and the new species described herein to be elucidated.     

Description of Sclerorhabditis miniata n. sp. and First Description of Male of Diploscapter coronatus Cobb, 1913 (Nematoda: Rhabditidae)

A population of Sclerorhabditis miniata n. sp. is described and illustrated from Poonch district of Jammu and Kashmir State, India. The new species is characterized by small body size, with an annulated cuticle, offset labial region, crown shaped, strongly sclerotized lips, thin lateral lips, membranous, stegostom without glottoid apparatus, cheilostom rod shaped, sclerotized, spicules free, strong and thick, gubernaculum simple, bent proximally, bursa open, peloderan with seven pairs of bursal papillae in 1+1/1+1+2+1 pattern. The males of Diploscapter coronatus are described for the first time. They are usually smaller than the females and have labial region similar to females. Spicules separate, with a small dorsal velum, gubernaculum simple, almost straight, bursa open, pseudopeloderan with seven pairs of bursal papillae in 1+1/1+2+1+1 pattern.     

Review of Ptycholaimellus Cobb (Nematoda, Chromadoridae), with descriptions of three species

Nematodes of the genus Ptycholaimellus Cobb, 1920 are unique in possessing a collar by which the head is separated from the body. The collar is raised from a groove at the border between the neck and the remainder of the body. The contents of the ventral gland cell are emptied in the groove in at least 9 out of 14 species. It is suggested that the amphids are located in the groove. Fourteen species are considered to belong to Ptycholaimellus . Two Ptycholaimellus species are described as new to science, that is, P. jacobi sp.n. and P. vincxae sp.n.; P. ponticus (Fihpjev, 1922) is redescribed. Ptycholaimellus ponticus sensu Stekhoven (1950) and Boucher (1972) from the Mediterranean off France differs from the other Ptycholaimellus species by its subcuticular ornamentation and shape of spicules, hence these specimens are regarded as belonging to a new species: Ptycholaimellus boucheri sp.n. Chromadorissa inaequibulba Aminova & Galtsova, 1978 is transferred to Ptycholai- mellus as P. inaequibulbus. Ptycholaimellus ponticus from Europe and P pandispiculatus (Hopper, 1961) from the east coast of North America are assumed to have colonized brackish waters independently.     

New insight into the identification and molecular phylogeny of dagger nematodes of the genus Xiphinema (Nematoda: Longidoridae) with description of two new species

The genus Xiphinema constitutes a large group of about 260 species of plant‐ectoparasitic nematodes. The group is polyphagous and distributed almost worldwide. Some of the species of this genus damage agricultural crops by direct feeding on root cells as well as by transmitting nepoviruses. Species discrimination in Xiphinema is complicated by phenotypic plasticity leading to potential misidentification. We conducted nematode surveys in cultivated and natural environments in Spain from 2009 to 2012, from which we identified 20 populations of Xiphinema species morphologically close to the virus‐vector nematode species Xiphinema diversicaudatum, three apomictic populations tentatively identified as species from the complex Xiphinema aceri‐pyrenaicum group, and one population morphologically different from all others that is characterized by a female tail elongate to conical and absence of uterine differentiation. We developed comparative multivariate analyses for these related species by using morphological and morphometrical features together with molecular data from nuclear ribosomal DNA genes [D2‐D3 expansion segments of large ribosomal subunit 28S, internal transcribed spacer 1 (ITS1), and partial small ribosomal subunit (18S)]. The results of multivariate, molecular, and phylogenetic analysis confirmed the morphological hypotheses and allowed the delimitation and discrimination of two new species in the genus described herein as Xiphinema baetica sp. nov. and Xiphinema turdetanensis sp. nov. , and ten known species: Xiphinema adenohystherum, Xiphinema belmontense, Xiphinema cohni, Xiphinema coxi europaeum, Xiphinema gersoni, Xiphinema hispidum, Xiphinema italiae, Xiphinema lupini, Xiphinema nuragicum, and Xiphinema turcicum. Multivariate analyses based on quantitative and qualitative characters and phylogenetic relationships of Xiphinema spp. based on the three molecular ribosomal markers resulted in a partial consensus of these species grouping as nematode populations were maintained for the majority of morphospecies groups (e.g. morphospecies groups 5 and 6), but not in some others (e.g. position of Xiphinema granatum), demonstrating the usefulness of these analyses for helping in the diagnosis and identification of Xiphinema spp. The clade topology of phylogenetic trees of D2‐D3 and partial 18S regions in this study were congruent in supporting the polyphyletic status of some characters, such as the female tail shape and the degree of development of the genital system in species with both genital branches equally developed. This is the most complete phylogenetic study for Xiphinema non‐americanum‐group species. Agreement between phylogenetic trees and some morphological characters (uterine spines, pseudo‐Z organ, and tail shape) was tested by reconstruction of their histories on rDNA‐based trees using parsimony and Bayesian approaches. Thus, integrative taxonomy, based on the combination of multivariate, molecular analyses with morphology, constitutes a new insight into the identification of Xiphinema species. © 2013 The Linnean Society of London     

Revision of the genus Haemonchus Cobb, 1898 (Nematoda: Trichostrongylidae)

Summary Only nine species of the genus Haemonchus are considered valid, namely, H. contortus (Rudolphi, 1803) Cobb, 1898 (type), H. bedfordi Le Roux, 1929, H. dinniki Sach, Gibbons & Lweno, 1973, H. krugeri Ortlepp, 1964, H. lawrencei Sandground, 1933, H. longistipes Railliet & Henry, 1909, H. mitchelli Le Roux, 1929, H. similis Travassos, 1914 and H. vegliai Le Roux, 1929. These are redescribed. H. bispinosus Molin, 1860, H. placei Place, 1893, H. cervinus Baylis & Daubney, 1922, H. okapiae van den Berghe, 1937 (in part), H. tartaricus Evranova, 1940, H. contortus contortus Das & Whitlock, 1960, H. contortus cayugensis Das & Whitlock, 1960, H. contortus bangalorensis Rao & Rahman, 1967, H. contortus hispanicus Martínez Gómez, 1968, H. contortus kentuckiensis Sukhapesna, 1974 and H. contortus var. uktalensis Das & Whitlock, 1960 are considered synonyms of H. contortus (Rudolphi, 1803) Cobb, 1898.The synonymy of H. lunatus Travassos, 1914, H. atectus Lebedev, 1929, H. pseudocontortus Lebedev, 1929 and H. fuhrmanni Kamensky, 1929 with H. contortus is confirmed. H. okapiae van den Berghe, 1937 (in part) is considered a synonym of H. mitchelli Le Roux, 1929 and H. bubalis Chauhan & Pande, 1968 is considered a synonym of H. similis Travassos, 1914. H. bovis Bonelli, 1941 and H. contortus var. kashmirensis Fotedar & Bambroo, 1965 are considered species inquirendae. An illustrated key to the species of the genus is provided.Part of a thesis approved by the University of London for the award of the Ph.D. degree.Part of a thesis approved by the University of London for the award of the Ph.D. degree.     

Two new species of Cephalobellus Cobb, 1920 (Thelastomatidae: Nematoda) from coleopteran larvae from India

Summary Two new species of Cephalobellus, C. annulobellus and C. spicatus, collected from unidentified coleopteran larvae in Aligarh, India, are described and figured. Both species have characteristic closely set annules in the cervical region of their females and five pairs of caudal papillae and lateral alae in the males. C. annulobellus possesses a labial disc, has a smaller body and different shape and arrangement of caudal papillae than in C. spicatus. A key to the species of Cephalobellus is given. ac]19830610     

Description of Longidorus fagi n. sp. (Nematoda, Dorylaimida) with an identification key to the species of the genus occurring in Bulgaria

Longidorus fagi n. sp. is described from Vitosha Mountain, Bulgaria, where it was found in soil around roots of Fagus sylvatica L. The new species is characterised by its medium size, narrow anteriorly rounded lip region which is offset from the body by a very slight depression, large amphidial pouches which are distinctly bilobed at the base, and a conoid-elongate tail which is ventrally curved with a narrow, rounded terminus. L. fagi resembles L. nirulai, L. distinctus, L. curvatus and L. fragilis, An identification key for species of the genus Longidorus present in Bulgaria is provided.     

A new species of arthropogon (Gramineae: Arthropogoneae) and a revised key for the genus

Arthropogon bolivianus is described as a new species. A revised key for the seven species of the genus is provided.     

A new species of Heth Cobb, 1898 (Nematoda: Rhigonematida: Hethidae) from an Australian millipede (Myriapoda: Diplopoda: Spirostreptida)

Abstract

A new species of nematode, Heth baudini sp. n. from a diplopod (Spirostreptida: Iulomorphidae Verhoeff, 1924) collected in Queensland, Australia, is described and illustrated. The cephalic and cervical cuticular ornamentation of females of H. baudini sp. n. is similar to those of South-East Asian and Australasian Heth species. Heth baudini sp. n. females are particularly close to Heth taynguyeni from Vietnam but can be distinguished by the shape of the lateral lappets, which in H. taynguyeni limit the trapezium-shaped region of smooth cuticle unlike the elliptical region in H. baudini sp. n., and by the presence of lateral spines only half the size. The cuticle of the H. baudini sp. n. is finely annulated along the entire body, whereas H. taynguyeni has broader rings behind the first pair of lateral spines, each consisting of five or six narrower rings separated from each other by deeper furrows. Males of H. baudini sp. n. are characterised by the presence of a bursa-like fold on the tail and can be distinguished from other species of the genus by the presence of somatic papillae embedded into the bursal fold.