Micromiceti Nuovi O Rari per L'Italia, Isolati da Terreno di Bosco del Litorale TirrenicoHumicola ParvisporaN.SP. EGonytrichum Macrocladum(Sacc.) Hughes Var.TerricolaN. Var

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Abstract
New or rare microfungi of Italy, isolated from coastal forest soil of Tuscany. « Humicola parvispora » n. sp. and « Gonytrichum macrocladum » (Sacc.) Hugh. v. « terricola ». n. var. — Two molds, a Humicola and a Gonytrichum species, isolated from coastal soils of Tuscany, are described. The history of the genus Humicola is shortly reviewed; regarding its generic features, some characters described for more recent species (possible absence of fialides, aleuriospore catenulation, chlamydospore formation) are considered and connexions with similar genera are discussed together with the possibility of utilising physiological and/or ecological characters. The present strains is mainly characterized by the presence on hyaline hyphae of small, brown or dark-brown, smooth, globose or subglobose (μ 4,2-6-8,4), pyriform or broadly clavate (μ 3,6-4,8-6,6 × 5,4-8,8-12) aleuriospores, single or in small aggregations, together with the presence of chlamydospores or toruloid/chlamydosporioid bodies. A new species is proposed: H. parvispora, About the strain of Gonytrichum, its fundamental features, as well as its morpho-metrical characters, allow to consider it as G. macrocladum (Sacc.) Hughes. However, some other characters have been evidenced which do not agree with those already described for this species. Simple conidiophores of Bisporomyces-type are present; conidia production at apex of conidiophores as well as of lateral phialides occurs in pairs, one conidium is but slightly successive to the other, like in Bisporomyces lignicola Mangenot. There was no possibility to evidence a double opening at apex of phialides, as described by Swart, but only an imperceptible joint of young conidium with phialide, until it is out of collarette. Phialides of second order on proliferating first order phialides have been observed, even rarely and under particular conditions. Sometimes the main axis shows a sort of ‘bifurcation’ that is here interpreted as something like a direct branching. All these features, together with the occurrence of the fungus in soil, seem to indicate the presence of a subspecific taxon of Gonytrichum macrocladum (Sacc.) Hughes. It is therefore proposed to establish the new variety terricola.