Only two other species of Cashiella have been described. The main morphological characters of these and the new species are given in Table 5.

This fungus was found in a patch of about 1 ha where dieback of S. cunninghamii was occurring. It is unlikely that C. sticheri was responsible for the condition as it was not consistently associated with plants suffering from dieback.

(The specific epithet is derived from the generic name of the host plant).

Chalara myrsines is distinct from all Chalara species described in the monograph by Nag Rai & Kendrick (1975), those noted by Morgan-Jones & Ingram (1976), Kile & Walker (1987), Kowalski & Halmschlagcr (1996), and from the two species described from the Chatham Islands (C. dracophylli and C. distans) by McKenzie (1993). It is close to Chalara australis Walker & Kile and C. neocaledoniae Kiffer & Delon but differs from both in conidial size and particularly in the collarette:venter ratio (see Table 3 for a comparison [not provided here]).

Most of the remaining stands of indigenous forest on the Chatham Islands are in poor condition, attributable to disturbance by introduced grazing animals which have been permitted to range and browse freely. Exclusion of stock from such stands in recent years has generally led to an improvement in stand vigour. Chalara myrsines was isolated from discoloured wood from the roots and lower stem of dying M. chathamica trees in a mixed stand which were in a state of decline although the stand was fenced off as a reserve. The trees were also being colonised by the pinhole borer Platypus apicalis White and by a pit weevil (Psepholax sp.). Chalara myrsines was commonly but not always associated with the tunnels of these wood-boring insects. Many species of Chalara are known as wilt pathogens (Nag Raj & Kendrick 1975) and it is possible that infection by C. myrsines is one of the causes contributing to the decline of M. chathamica in the Chatham Islands.

(The specific epithet refers to Mahinapua Forest, the location of the holotype).

Sarcostroma mahinapuense has been consistently found on swollen, fissured cankers on branches of Eucalyptus nitens (14-19 years old) growing in Mahinapua Forest on the West Coast of the South Island. The cankers were first noticed in August 1998 and by June 1999 were to be found in about 60 ha of E. nitens. The number of cankers per affected tree had increased over this period and dieback, associated with cankers on smaller branches, was occurring. This fungus has also been recorded on E. regnans from Rotorua where it was associated with twig lesions and minor dieback. A further collection of the fungus was made in 1998 from the Nelson bioregion where it was associated with minor dieback ofEucalyptus sp. Sarcostroma mahinapuense appears to be acting as a pathogen on the West Coast. Its pathogenic status is being investigated.

The principal characters that separate S. mahinapuense from the other 5-septate Sarcostroma species are conidial length and the length:width ratio (Table 2).

S. mahinapuense spores 46 x 10 µm; L/W ratio 4.6:1; Apical appendage 15 µm; Basal appendage 12.5 µm
S. coryneoideum spores 34.5 x 10.2 µm; L/W ratio 3.4:1; Apical appendage 5.7 µm; Basal appendage 4.5 µm
S. foliicola spores 20.2 x 7.5 µm; L/W ratio 2.7:1; Basal appendage 6 µm; Apical appendage 6.5 µm
S. insidens spores 38 x 13 µm; L/W ratio 2.9:1; Apical appendage 17.3 µm; Basal appendage 17.8 µm
S. kennedyae spores 19 x 6.3 µm; L/W ratio 3:1; Apical appendage 15 µm; Basal appendage 13 µm
S. leucopogonis Spores 20.7 x 8 µm; L/W ratio 2.6:1; Apical appendage 2.2 µm; Basal appendage 3 µm
S. mariae Spores 25 x 5.7 µm; L/W ratio 4.4:1; Apical appendage 11 µm; Basal appendage 13.5 µm
S. plagiochaetum Spores 32 x 9 µm; L/W ratio 3.6:1; Apical appendage 10 µm; Basal appendage 7 µm
S. sinicum Spores 21.5 x 6.6 µm; L/W ratio 3.2:1; Apical appendage 6.5 µm; Basal appendage 7 µm

* Data for all species, except S. mahinapuense, are from Nag Raj (1993).

(The specific epithet refers to the typical Septorial appearance of the fungus with its long filiform conidia produced holoblastically from short conidiogenous cells).

Sankaran, Sutton & Minter (1995) did not record any recognised species of Septoria on Eucalyptus. One other species of Septoria (S. pulcherrima Gadgil & Dick) has been described on Eucalyptus in New Zealand (Gadgil & Dick 1983). Septoria pulcherrima conidia are hyaline to very pale brown, 30-60 x 3-4 µm and the conidiogenesis is of two types: holoblastic with enteroblastic proliferation of the conidiogenous cell, and holoblastic with sympodial proliferation (Swart 1988). These characteristics distinguish it from S. typica which has hyaline conidia, 60-70 x 2-3 µm, with simple holoblastic condiogenesis without any proliferation of the condiogenous cells. The binomial Septoria pulcherrima has been subject to several name changes and is now variously known as Kirramyces eucalypti or Phaeophleospora eucalypti. This is a pity as S. pulcherrima causes a serious leaf blight in E. nitens and a stable nomenclature would help those investigating the disease.
Septoria typica is associated with necrotic leaf spots. Fruiting bodies of Cryptosporiopsis eucalypti are also frequently seen on these spots. It is likely that C. eucalypti, which is pathogenic to species of Eucalyptus (Sankaran, Sutton & Balasundaran 1995), is the primary agent responsible for the necrotic spots, with S. typica as a secondary invader.