Archiv für Protistenkunde最新文献

The morphology and morphogenesis of a population of the hypotrichous ciliate Gonostomum strenua, found in moss samples from emergent stones collected in the Guadarrama River (Central Spain) is described. This population shows slight variations in morphology compared to the Chinese population studied by Song, (1990). The main differences between the European and Asian population appear in the first stages of morphogenesis. New data on infra-ciliature and cysts are also shown.

Three new species of actinocephalid gregarines (Apicomplexa: Sporozoea: Eugregarinida: Septatina), Actinocephalus longus sp. n., Mukundaella vannusus sp. n. and Odonaticola truncatus sp.n. from the midguts of Enallagma pervumSelys, Onychogargia atrocianaSelys and Pseudagrion decorumRambur respectively, are described. One known species, Hoshideia polyhamatus (Hoshide, 1977) Sarkar, 1995 is reported from a new locality, i.e. the Mahananda Forest of West Bengal, India.

The actual spatial configuration of the flagellar apparatus in biflagellate zoospores of the terrestrial green alga Leptosira erumpens is described. The basal bodies are displaced with respect to each other in the counter clockwise direction (CCW). The two types of microtubular roots consist of 2 microtubules (R2) and 8 microtubules (R8) respectively. The latter type of microtubular root is arranged in a 7-over-1 orientation. The two basal bodies are connected to each other anteriorly by a large striated distal connecting fibre. The microtubular roots are connected to the adjacent basal body via a striated proximal fibre and linked with the lower side of the distal connecting fibre. A single striated rhizoplast runs from one basal body along a large mitochondrion towards the nuclear envelope. The distinct eyespot (stigma) is intimately associated with a series of ca. 10 microtubules originating from one of the eight-membered microtubular roots.

In order to investigate the role that non-molecular characters play in the understanding of evolutionary relationships within the Microthamniales, a datamatrix was compiled for a preliminary phylogenetic analysis. Along with the present data of L. erumpens non-molecular (in great majority morphological) data of 15 more microthamnialean species and 2 selected outgroup species were included within this set. Despite incompleteness of the data, a distinct phylogenetic signal was found. This encouraged us to compare our results with a recent phylogenetic reconstruction based on molecular data.

Victoriniella multiformis gen. et sp. nov. is a polymorphic parasitoid of uncertain taxonomic position that infects the marine centric diatom Coscinodiscus wailesii. Motile trophozoites attached to the diatom protoplast by means of a pseudopodium which was also used for incorporation of host cytoplasm. At the end of the trophic phase several filose pseudopodia were frequently formed which were used for locomotion. Thereafter, two divisions frequently followed, and led to the formation of cone-shaped cells of characteristic shape which left the empty frustule. Among the offspring two forms of motile stages were observed: Cells of type A were free-swimming and possessed two anterior inserted flagella, whereas cells of type B did not swim but moved by means of two contractile filopodia. Occasionally, cyst formation was observed inside infected diatoms.

Distinct homogeneous clusters of established diatom taxa are described as three new genera. Only the nomenclatural type of the first genus, Frankophila similioides, is introduced as a new species. Two other species, F. loetschertii and F. maillardii belong to this genus with a unique complex of characteristic features of the Fragilariaceae, in particular of the subgenus Staurosira, and of naviculoid Raphideae. Actually 13 taxa of Navicula sensu lato belong to Mayamaea with M. atomus as type species whereas Navicula pelliculosa, Navicula saprophila and Navicula iranensis are transferred to Fistulifera. In addition to these proposals Stauroneis spicula is transferred from the actually used combination Navicula spicula to the genus HasleaSimonsen.