Type: Radicicolous Fungi; Description: Colonies on malt extract agar olivaceous. Conidiophores occurring singly or in groups of up to six, stipe erect, 350–750 μm long, olivaceous, simple, bearing 2–4 primary metulae, 25–55 μm long; three to four additional series occur above the primary metulae, each giving rise to 2–3 further metulae at the apex; primary metulae olivaceous, subsequent metulae olivaceous to hyaline. Conidio-genous cells discrete, tapering slightly, 12–23 μm long, hyaline. Conidia obovoid with truncate ends, 0-septate, 4–6 × 2–3 μm, smooth, hyaline, accumulating in a mucilaginous mass.

Distribution: Northland, Auckland, Coromandel, Waikato, Bay of Plenty, Taranaki, Taupo, Rangitikei, Wanganui, Wellington, Gisborne, Hawkes Bay, Wairarapa, Nelson, Westland, Marlborough Sounds, Marlborough, North Canterbury, Mid Canterbury, South Canterbury, Dunedin, Southland.; 1st Record: Dick (2004).

Significance: See under Leptographium procerum (p. 172).; Host(s): Pinus radiata, P. strobus.

This is a segregate from collections originally tentatively identified as Verticicladiella procera (=Leptographium procerum) (Wingfield and Marasas 1983). Jacobs et al. (2001) examined many isolates of L. procerum sensu lato and determined that four morphologically different groups could be distinguished. One of these groups represented L. procerum sensu stricto and the other three were described as new species — L. alethinum (from England and Scotland), L. pityophilum (from Italy), and L. euphyes (from New Zealand). A re-examination of cultures of L. procerum and of unidentified Leptographium species held in the New Zealand Forest Research Institute culture collection (NZFS) showed that a number fitted closely with the description of L. alethinum provided by Jacobs et al. (2001). The description of L. alethinum given above is based on these cultures. It should be noted that the conidiophores in the New Zealand collections are shorter (450–910 m) than those described by Jacobs et al. (2001) (560–1270 m), and that rhizoids are consistently present in the New Zealand collections while they are described as being occasionally present by Jacobs et al. (2001).