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Pythium stipitatum is a slow-growing oomycete and has been isolated from soil samples and plant materials from France, Tunisia, Turkey and India. Its morphological characteristics are reminiscent of those of Pythium ramificatum, discovered in Algeria by the corresponding author. Unfortunately, the Algerian isolate was not deposited in any culture collection and ultimately got lost. Those were the days when molecular description of fungi was not a fashion; hence, no molecular characteristics of the Algerian isolates were deposited to the GenBank. Moreover, its coralloid antheridial branches made it an easy prey to be considered as synonymous to Pythium minus. Because there are no living strains of P. ramificatum, and no sequence at the GenBank, it is being treated as ‘ nomen invalidum’ here. However, we have now isolated the same type of oomycete from four different countries and we have sufficient evidence, both molecular and morphological, to describe it as a new species, quite different from P. minus. In this article, we are giving the morphological and molecular evidence to separate it as a distinct species, P. stipitatum, belonging to the ‘Clade E’ of the genus Pythium. Taxonomic description of this oomycete, its comparison with related species, and the sequence of the internal transcribed spacer region of its rRNA gene, are discussed here. [ABSTRACT FROM AUTHOR]

Achlya spiralis sp. nov. was isolated from water samples collected in the river Tille in the Burgundian region of France. The new oomycete is described, illustrated and compared with related species of the genus Achlya. It is characterized by the presence of smooth-walled oogonia that are usually borne on bent or twisted oogonial stalks; mainly monoclinous, androgynous and diclinous antheridial branches and eccentric oospores which generally do not mature or mature after a long period of time. The internal transcribed spacer (ITS) region of its rRNA is comprised of 671 bases. The taxonomic description of this new species, its comparison with related oomycetes and the sequence of the ITS region of its rRNA are discussed here. [ABSTRACT FROM AUTHOR]