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Page number:618 
Description type:Non-original description 
Description:Alternaria intercepta E.G. Simmons, Mycotaxon 83: 134. 2002. - Fig. 255
Type (holotype): BPI 841917 (dried culture preparation ex E.G.S. 49.137, from isol. E. Simmons ex one ascospore of teleomorph Lewia intercepta E.G. Simmons & McKemy, coll. USDA/APHIS Chicago no. 841916, ex or via The Netherlands, spring 2001).
Host/substrate: Viburnum sp. (Caprifoliaceae)
Manual basis: Simmons 2002, Alt.T&V 306 (Fig. 220); representative isolate E.G.S. 49.137 (ex-type), CBS 119406
Culture at 50X, 5-7d, PCA & V-8: colony 6 cm diam, with 2-3 moderately well-defined pairs of concentric rings of growth and sporulation on PCA, 3 well-defined pairs on V-8. Sporulation on cut agar surface, 2 d: PCA ++, V-8 +++
Young colonies (3-4 d. on PCA) are arachnoid to loosely cottony and practically devoid of sporulation. Colonies retain this open texture as they age and begin to produce loose clumps of branching chains of conidia. Within 7-10 days nearly all aerial hyphae have produced clusters of sporulation, as have the spreading surface hyphae. Surface sporulation on PCA in light-exposed rings of growth is in bushy clumps of abundant but not densely crowded, branching chains of small conidia. Individual clusters of chains have a diverging branching appearance (at 50X) rather than that of a dense clump of conidia; clusters are spaced in such a fashion that the colony has a granular appearance when viewed without magnification. Longest chains in a cluster have 10-15 conidia; individual clusters have a few dozen to a few hundred conidia.
Conidia are ovoid and erostrate, never with a beak portion distinguishable from the spore body. Conidium size reaches a range of 25-28 x 8-10 µm; most conidia are smaller, with great numbers of them in the longer chains consisting of only one or two cells plus a distal secondary conidiophore. Conidia have up to 6-7 transepta and one longiseptum in the wider segments of most conidia. Although exceptionally long or unusually multigeniculate secondary conidiophores are present in some position in most conidial chains of A. intercepta, they do not dominate the structure of the branching sporulation apparatus (in contrast to the pattern in A. viburni on the same host). Typically, each exceptional secondary conidiophore is at least as long or commonly 2-3 times as long as the conidium that produced it; it usually is geniculate and conidiogenous at 2-5 loci along its length. All other conidia (except terminal ones in the branching chains) bear a simple 1-cell apical conidiophore. Conidium color is a dilute tan; outer walls are smooth to punctate.
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