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Volume 11, Part 2 (2003)

  • A. Holovachov and D. Sturhan. Adelonema camerunense gen. et sp. n. (Araeolaimida, Diplopeltidae) from rain forest in Cameroon, 63-66.
  • R. Crozzoli and F. Lamberti. Species of Criconemoides Taylor, 1936, Discocriconemella De Grisse & Loof, 1965 and Hemicriconemoides Chitwood & Birchfield, 1957 occurring in Venezuela, with description of Criconemoides tiaraensis sp. n. (Nematoda: Criconematidae), 67-80
  • V. V. Yushin. . Ultrastructure of spermatozoa in the free-living marine nematode of the family Selachinematidae (Chromadorida: Cyatolaimina), 81-90.
  • S. Amiri, S. Subbotin and M. Moens. Comparative morphometrics and RAPD studies of Heterodera schachtii and H. betae populations, 91-100.
  • S. Bostrom. Ceratoplectus armatus (Bütschli, 1873) Andrássy, 1984 (Leptolaimina: Plectidae) from five sites on three continents, 101-106.
  • N. Kanzaki and K. Futai. Application of molecular phylogenetic analysis to the evolution and co-speciation of entomophilic nematodes, 107-118.
  • A. V. Adrianov. Marine biological diversity: patterns, processes and modern methodology, 119-126
  • A. L. Drozdov. Multikingdom system of living organisms, 127-132.
  • Abstracts of papers presented at the Fifth English Language International Symposium of the Russian Society of Nematologists (Vladivostok, 13-17 July 2003) , 133-76.

Holovachov, A. and Sturhan, D.

Adelonema camerunense gen. et sp. n. (Araeolaimida, Diplopeltidae) from rain forest in Cameroon

Summary:
Adelonema camerunense gen. et sp. n. (Araeolaimida: Diplopeltidae) from rain forest in Cameroon is described on the basis of light microscopy. The new genus is tentatively placed in the Diplopeltidae and distinguished from all other genera in the family by the following characters: cuticle with ten longitudinal ridges; ocelli, lateral field, epidermal glands, body pores, somatic setae and deirid absent; cephalic sensilla setiform; amphid a transverse slit; excretory pore posterior to nerve ring; stoma tubular; pharynx cylindrical with weak cardial bulb; tail elongate conoid with filiform terminus; caudal glands and spinneret absent; female gonads monodelphic, prodelphic; ovary branch outstretched; spermatheca an offset pouch; postvulval uterine branch present; male reproductive system diorchic; testes opposed; spicules arcuate; gubernaculum platelike; midventral precloacal setiform sensillum present.

Key words: Adelonema camerunense sp. n., Cameroon, Diplopeltidae, morphology, new genus, taxonomy.


Crozzoli, R and Lamberti, F. .

Species of Criconemoides Taylor, 1936, Discocriconemella De Grisse & Loof, 1965 and Hemicriconemoides Chitwood & Birchfield, 1957 occurring in Venezuela, with description of Criconemoides tiaraensis sp. n. (Nematoda: Criconematidae)

Summary:
One known species of Criconemoides Taylor, 1936, one of Discocriconemella De Grisse & Loof, 1965, three of Hemicriconemoides Chitwood & Birchfield, 1957 and Criconemoides tiaraensis sp. n. are described from Venezuela. C. tiaraensis sp. n. resemble C. lizarbus; from which it differ in its longer stylet and smooth margin of the body annules. Additional morphometric information is provided on C. lizarbus van den Berg & Marais, 1995, D. limitanea (Luc, 1959) de Grisse & Loof, 1965, H. cocophillus (Loos, 1949) Chitwood & Birchfield, 1957, H. communis Edward & Misra, 1963, H. strictathecatus Esser, 1960. C. lizarbus and D. limitanea constitute new records from Venezuela.

Key words: Criconemoides, Criconemoides tiaraensis sp. n., Discocriconemella, Hemicriconemoides, taxonomy, species, Venezuela


Yushin, V. V.

Ultrastructure of spermatozoa in the free-living marine nematode of the family Selachinematidae (Chromadorida: Cyatolaimina)

Summary:
Halichoanolaimus possjetiensis (Selachinematidae, Chromadorida) were studied electron-microscopically. The spermatozoa from the testes are unpolarized cells covered by numerous short filopodia. They contain the centrally located nucleus without a nuclear envelope. The centrioles were observed at the nuclei. The spermatozoan cytoplasm includes mitochondria and spherical fibrous bodies (FB) embedded into the transparent matrix. The spermatozoa from the uterus lack the dramatic changes which are common after fertilization. Their nuclei, mitochondria, FB, and surface filopodia remain intact. The outfoldings resembling short lamellipodia occur on the spermatozoan surface. The spermatozoa of H. possjetiensis lack the large pseudopod and membranous organelles (MO) - a characteristic feature found in many nematode spermatozoa. The occurrence of the FB never associated with MO differentiates H. possjetiensis from many nematodes so far studied, but unites the chromadorids and tylenchids (Tylenchida). This conclusion is supported by the filopodial nature of the sperm surface demonstrated by both taxa.

Key words: Halichoanolaimus, fibrous bodies, FB, membranous organelles, MO, centrioles, filopodia, pseudopod, spermatogenesis, Tylenchida.


Amiri, S. Subbotin, S.A and Moens, M.

Comparative morphometrics and RAPD studies of Heterodera schachtii and H. betae populations

Summary:
The morphometrics of 25 populations of H. schachtii and two populations of H. betae from different origins were compared. Cyst length and width of H. betae were greater than those of H. schachtii. The fenestral length and semifenestral width did not support distinguishing the H. betae populations from the H. schachtii populations examined and, therefore, cannot be used to separate these species. In second stage juveniles body length, the hyaline part of the tail, and the tail length were significantly greater for H. betae than for H. schachtii and enable these species to be differentiated. The RAPD analysis using seventeen decamer primers and carried out on 20 H. schachtii populations, two H. betae populations and one of H. glycines yielded 471 DNA fragments. Some bands generated by primers were specific for H. schachtii. The dendrogram constructed on the basis of RAPD data did not arrange H. schachtii populations according to their origin but separated the two species.

Key words: beet cyst nematodes, interspecific differences, intraspecific variation.


Bostrom, S.

Ceratoplectus armatus (Bütschli, 1873) Andrássy, 1984 (Leptolaimina: Plectidae) from five sites on three continents

Summary:
Specimens of the cosmopolitan species Ceratoplectus armatus from five sites on three continents are described from studies by light microscopy and one population also by scanning electron microscopy. Some new biogeographical records are provided. The populations are compared with each other and with populations previously described. Some discrepancies in morphometry and morphological characters were found between specimens of different populations, but they were mostly within the ranges established for the species. Plectus incertus Maiello, 1967 is suggested to be a junior synonym of C. armatus. The possible phylogenetic importance of Ceratoplectus is briefly discussed.

Key words: Australia, Brazil, Ceratoplectus, Kenya, morphology, Plectus, scanning electron microscopy, West Indies.


Kanzaki, N. and Futai, K.

Application of molecular phylogenetic analysis to the evolution and co-speciation of entomophilic nematodes

Summary:
Molecular phylogenetic analysis was applied to two evolutional aspects of the genus Bursaphelenchus. For the first, the morphological and biological features of the six species of the genus Bursaphelenchus were compared with their molecular phylogenetic relationship, and then the evolutional sequences of these features were determined. For the second, phylogenetic correspondence between B. conicaudatus and its phoretic vector, Psacothea hilaris, was analyzed molecular biologically, and co-speciation between them was affirmed. The molecular analysis also suggested that the paleogeographical events must be determinant of the co-speciation. The present results ascertained 1) the effectiveness of the molecular phylogenetic analysis in the evolutional studies of nematodes, and 2) the validity of Bursaphelenchus species in the xylophilus group as the model organisms of entomophilic nematodes in the study of the molecular co-speciation.

Key words: biological features, co-speciation, evolution, molecular phylogeny, morphology, xylophilus group.


Adrianov A. V.

Marine biological diversity: patterns, processes and modern methodology

Summary:
Terminology and main components of biodiversity have been discussed. Species richness and taxonomic diversity of terrestrial, freshwater and marine organisms are compared. About 1.5 million of terrestrial species and only 325 000 species of water organisms have been described up-date. Despite more than 200 years of intensive researches biologists have described only about 280 000 marine species including about 180 000 marine invertebrates. Of the 33 phyla of Metazoa listed, 31 phyla are found in the sea, 13 of which are exclusively marine. Only 17 phyla are found in the fresh water and 11 phyla are found in terrestrial environments. Representatives of 4 parasitic phyla of Metazoa are found in the sea and only 2 phyla are represented in fresh-water and terrestrial hosts. Only two phyla, the fresh water Micrognathozoa, and the terrestrial Onychophora, are non-marine endemics. Diversity of the deep-sea macrobenthos and meiofauna are argued. Approximately 20-30 million undescribed macrobenthic species and about 20-30 million of meiobenthic species, including more than 10 millions of marine nematodes, are suggested, mainly in the deep-sea, based on modern extrapolations. Hypothesis to explain high benthic species diversity in the deep-sea sediments are summarized. New initiatives and methodology of marine researches are discussed.

Key words: biodiversity, deep-sea, macrobenthos, meiofauna, species richness.


Drozdov, A. L.

Multikingdom system of living organisms

Summary:
Analysis of present-day knowledge clearly indicates that the polyphyly of the traditional five kingdoms of the Whittaker-Margulis system, Plantae, Mycota, Animalia, Protoctista and Monera, is untenable. The multikingdom system of living organisms is proposed on the basis of the principle of cellular structures conservatism. This complex approach, based on an analysis of features on three levels, molecular, cytological and morphological, is needed for its construction.

Key words: cellular structure conservatism, living organisms, megasystematics, natural multikingdom system