(1) Disoxylon spectabile, North Auckland, Puketi Forest, 20. VI. 1963, J. M. Dingley, DAOM 93751; (2,3) Vitex lucens, Auckland Province, Piha, Waitakere Range; (2) 31.I.1963, S.J.H., DAOM 143999; (3) 31.VII.1963, J.M.D., PDD 36098 (type) (DAOM 109629); (4) unidentified branch, Auckland Province, Cornwallis, 3.I. 1963, S.J.H., DAOM 143998.

Colonies effuse, black, hairy. Mycelium immersed, composed of branched, septate, pale brown hyphae 3.5-9 µm wide. Conidiophores scattered or crowded, arising singly or sometimes in pairs or threes, mostly simple, straight or flexuous, subcylindrical, dark brown to black below, paler above, thick-walled (up to 2.7 µm), septate at 12-45 µm intervals, 165-330 µm long, 12.5-14.5 µm wide just above the base which is swollen and 18-21.5 µm wide, 10-11 µm wide just below the apical cell which is slightly swollen and 11.5-13.5 µm wide. After conidium secession the apical cell bears a conspicuous terminal "pore" and occasionally a second subapical or lateral pore; one or two similar pores are found in 1-3(-4) other distal cells of the conidio phore. Pores are 1.3-1.8 µm wide and indicate the positions at which solitary conidia developed.

Conidia obclavate to fusiform, sometimes shortly rostrate, smooth, golden brown to dark brown, paler toward the apex, (5-)6-7(-8)-septate, 56-63 x 20-21.5 µm (5-septate), 63-81 x 16-21 µm (6-septate), 74-90 x 18-23.5 µm (7-septate), 88-103 x 19-21 µm (8-septate). Terminal conidia are straight but attached lateral ones are seen to be upwardly curved.

Coloniae effusae, atrae. Mycelium immersum, ex hyphis septatis, ramosis, pallide brunneis 3.5-9 µm crassis compositum. Conidiophora plerumque singulariter nata, erecta, plerumque simplicia, recta vel flexuosa, subcylindrica, septata (cellulis 12-45 µm longis), basim versus. atro¬brunnea vel atra, apicem versus pallidiora, crasso-tunicata (ad 2.7µm), 165-300 µm longa, ad basim inflata (18-21.5 µm), supra basim 12.5-14.5 µm crassa, apicem versus 10-11 µm crassa, cellula terminali parce inflata (11.5-13.5 µm) poris 1 vel 2 in apice conidiiferis praedita, cellulis subterminalibus 1-3(-4) etiam poris 1 vel 2 laterali¬bus conidiiferis praeditis. Conidia ad poros conidiophori oriunda, obclavata vel fusiformia, interdum breviter rostrata, laevia, brunnea vel atrobrunnea, (5-)6-7(-8)-septata, 56-63 x 20-21.5 µm (5¬-septata), 63-51 x 16-21 µm (6-septata), 74-90 x 18-23.5 µm (7-septata), 88-103 x 19-21 µm (8-septata). Conidia apicalia recta sed lateralia curvata.

Holotypus in ligno putrido Viticis lucentis, Nova Zelandia, "Auckland Province, Piha, Waitakere Range", 31. VII. 1963, J. M. Dingley, PDD 36098 (DAOM 109629).

Broken or damaged conidiophores may regenerate percurrently and reach a length of 450 µm or they may produce one or two lateral branches which are conidiogenous. The presence of occasional lateral branches in some of the collections suggests, at first sight, a Dendryphiopsis but such branching is sporadic and the result of regeneration after damage. The apex of conidia frequently gives the appearance of having gelatinised and this may be accompanied by the formation of a new wall below the old apex.

Helminthosporium novae-zelandiae may be distinguished from other species of the genus by its relatively short conidiophores and by the conidia which are predominantly 6- or 7-septate, broad in relation to their length, and finally dark brown.