Cruznema velatum sp. n. from Mexico is differentiated by elongated tail and advulval cuticular membranes formed by lateral fields. C. tripartitum (LINSTOW) is briefly redescribed, and the generic characters of Cruznema ARTIGAS are discussed.
Studies of moss and soil nematode communities in four age classes of the Scots pine forest In the Białowieża primeval forest demonstrated relatively low number of species. The species diversity and ecological complexity of the communities increases as the shadowing of the forest floor increases. The maturation of the forest is associated with the increase of the proportion of fungivores and decrease of bacteriovores in the soil nematodes communities.
Dimensions and ratios of three Psilenchus species are examined for their variability. None of the studied ratios fits requirements for species characterization, as outlined in recently published studies. However, use of ratios is not rejected because inherent gene pool of each species limits the size of nematode allowing to use ratios, which are not mathematically correct. P. klingleri sp. n., from Switzerland, is characterized by anterior position of metacorporeal bulb, very posterior position of dorsal oesophageal gland orifice, and long, thin tail with pointed tip. P. terextremus, P. hilarulus, P. aestuarius, and P. iranicus are redescribed. Tabular key for Psilenchus species is presented.
The following species are redescribed: Prismatolaimus dolichurus, P. intermedius, P. matoni, P. parvus and P. primitivus. Selection of neotypes of Prismatolaimus dolichurus and P. intermedius stabilizes these species. The following new synonyms are proposed P. eurylaimus and P. dolichurus, P. tareya and P. primitivus. P. intermedius sensu Mulk et Coomans, 1979 is considered a distinct species and is described as P. mulcomus sp. n.
The measurements of eight populations of Nagelus obscurus (Allen, 1955) are presented and compared with the published data. This increased known limits of the species and lead to proposal of new synonyms: Merlinius camelliae Kheiri, 1972 and Nagelus alpensis Doucet et Luc, 1981 are considered conspecific with N. obscurus. New morphometric data for N. leptus (Allen, 1955) are given and published informations are summarised showing known variation limits for this species.
Analyses of 179 pine wood samples and 73 wood chips samples from sawmills showed presence of four species of Bursaphelenchus, B. mucronatus being the commonest (7.5 % of samples). The identification of species was done using microscopic as well as RAPD-PCR methods.