Sporidesmium arengae Matsush. 1975
Details
Sporidesmium arengae Matsush. 1975
Nomenclature
Matsush.
Matsush.
1975
136
ICN
Sporidesmium arengae Matsush. 1975
species
Sporidesmium arengae
Classification
Descriptions
Sporidesmium arengae Matsush. 1975
On dead sheathing base of leaves of Rhopalostylidis sapida, Auckland Prov., Piha, 31.1.1963, PDD 20494 (DAOM 96158).
Conidiophores are composed, at first, of a simple, erect main stalk which bears a single, terminal blastic conidium at its apex. The main stalk is subulate, 130-270um long, 7-8.5µm wide at the base, 3.5-4.5µm wide at the apex, septate at 20-40um intervals, dark brown to black toward the base, slightly paler at the apex. After the secession of the conidium a terminal proliferation occurs through the scar on the main stalk; this is cylindrical with a slightly swollen basal cell, dark brown, 18-130um long with up to 4 other septa in the longer proliferations. Such proliferations bear a terminal conidium. In the meantime the basal cell of the proliferation is producing a lateral extension which curves sharply downward and grows adpressed to the main stalk finally to a length of up to 35 um. This recurved hypha is brown to dark brown toward its base, paler and narrowed toward its apex, and up to 7-celled. The basal cell of this hypha -next to the basal cell of the original proliferation - produces a lateral extension which grows upward to a length slightly less than the original proliferation and also terminates in a conidium. Together, these growths form a characteristic 'V' at the apex of the main stalk- Successive lateral branches also arise in acropetal succession from a few of the other cells of the downwardly directed hypha; they are successively shorter (to 8 um) toward the apex of that hypha and each terminates in a conidium. In older and more mature conidiophores the original proliferation of the main stalk and one ormore of the fertile lateral branches of the recurved hypha have proliferated in the same manner as the apex of the main stalk; such secondary proliferations and the recurved hyphae that they produce result in complicated branched systems, sonic of which are illustrated in Fig. 44. These branched systems are readily detached from the apex of the main talk of the conidiophore. Conidia are blastic, obovoid, uniformly brown to dark brown or slightly paler toward the base, predominantly 3-septate (pseudoseptate) with the walls progressively thinner toward a slightly raised hasal scar which is 2.7-4.5um wide. Conidia measure 26-41 x ( 1 1.7-)12.5-18um. Matsushima (1975) described this species from a culture of the fungus obtained from a leaf ofArenga engleri (Palmae) from Ishagaki Island, Okinlwa. The illustrated account indicates that the fungus is less robust in culture than on the host and the branching less highly developed. The essential details, however, are identical with the New Zealand collections; Matsushima described the conidia as 27-37 X 12-16um and 3-septate.
Because of the bizarre recurved fertile branch produced at the base of each percurrent proliferation this species should be excluded from Sporidesmium. It may require a new form genus.
Taxonomic concepts
Global name resources
Collections
Notes
typification
Type Japan
Metadata
1cb1a512-36b9-11d5-9548-00d0592d548c
scientific name
Names_Fungi
15 December 1992
10 May 2011