Both host and fungus are indigenous to New Zealand; it forms a leaf spot on Leptospermum. It is of no economic importance.

Type: Foliicolous Fungi; Description: Ascomata perithecial, scattered, immersed, occupying the whole leaf thickness, globose, black, shining, 0.3–0.4 mm in diameter, with a black brown clypeus covering the whole perithecium, ostiole perforating the epidermis and appearing as a small black dot; on upper surfaces of leaves, without any distinct leaf spots. Asci cylindrical, 80–115 × 8–10 μm. Ascospores ellipsoid, 0-septate, 11–13 × 7–8 μm, smooth, hyaline.

Distribution: Auckland, Coromandel, Wellington, North Canterbury, Southland.; 1st Record: Hansford (1957: as Phomatospora leptospermi).

Significance: None.; Host(s): Leptospermum scoparium.

Perithecia scattered or rarely 2-aggregate, immersed, occupying the whole leaf thickness with both surfaces slightly raised, black, smooth, shining, with central round pore in upper surface; epidermal clypeus amphigenous, the upper covering the whole perithecium and extending downwards around its sides into the palisade tissue, up to 55 µ thick, opaque black-brown, parenchymatous; lower clypeus less extensive and thinner; loculus to 350 µ diam. and 400 µ high. Perithecial wall thin, of much compressed hyaline parenchyma, including some browned host cells, appearing concentrically fibrous. Asci cylindric, narrowed below into short stipe, thin-walled, rounded and slightly thickened at apex, with internal refringent apical ring about 5 µ diam. and l µ thick, 8-spored, to 115 x 8-10 µ, p. sp. about 80 µ long. Spores obliquely 1-seriate, ellipsoid, continuous, hyaline, smooth, 11-13 x 7-8 µ, with granular contents. Paraphyses few, equalling the asci, filiform, 2-2.5 µ thick, doubtfully septate, simple.

Maculae nullae. Perithecia dispersa vel raro 2-aggregata, immersa, atra, levia, nitentia, usque ad 350 µ diam. et ad 400 µ alt.; clypeus amphigenus, superior usque ad 55 µ cr., opace atrobrunneus, parenchymaticus, perithecium totum obtegens et lateraliter in parenchymatice mesophylli descendens, clypeus inferior minor et tenuior. Paries perithecii tenuus, hyalinus, concentrice fibrosus, ex cellulis fortiter compressibus compositus. Asci cylindracei, tenuiter tunicati, breviter stipitati, apice rotundati et leniter incrassati, annulo interno refringente 5 µ diam. et l µ cr., p. sp. circa 80 µ long., asci usque ad 115 x 8-10,u, 8-spori. Sporae oblique 1-seriatae, ellipsoideae, obtusae, continuae, hyalinae, leves, 11-13 x 7-8 µ, intus granulosae. Paraphyses paucae, ascos aequantes, filiformes, 2-2.5 µ cr., dubiter septatae, simplices.

Hab. in foliis Leptospermi scoparii, Auckland, New Zealand, Dingley in DSIR 17247.