It is recorded only from the type locality, Silverdale, North Auckland. Both host and fungus are indigenous to New Zealand.

Stromata culmicolous, black, shining, smooth, slightly swollen, closely scattered or sometimes confluent, to 5 x 2 mm., elliptic, marked with the punctiform apical pores of the loculi. Stroma tissue filling the epidermis and underlying parenchyma with subopaque dark brown parenchyma, extending to 600 µ deep and enclosing the perithecia, dissolving outwards into pale brown, subhyaline to hyaline, branched, septate, intercellular hyphae in host parenchyma. Perithecia completely immersed below the vascular bundles of the host, flask-shaped with neck to 200 µ long and 90 µ diam. opening between the vascular bundles and lined with delicate hyaline periphyses, penetrating the clypeal tissue as a flat pore on the surface; body of perithecium to 330 µ diam., globose, or where crowded, flattened and occasionally partially confluent with others; perithecial wall hyaline, about 10 µ thick, composed of much compressed parenchyma and appearing concentrically fibrous. Asci formed over the lower two-thirds of the internal surface, erect, convergent towards the neck of the perithecium, mixed with numerous, filiform, hyaline paraphyses, which are sometimes furcate above, doubtfully septate, 1-2 µ thick, equalling the asci. Asci narrow cylindric, rounded at apex, shortly stipitate, thin-walled, 4-(8)-spored, 120-140 x 10-11 µ. Spores obliquely 1-seriate, slightly overlapping, ellipsoid with rounded ends, hyaline, continuous, smooth, 22-26 x 7.5-9.5 µ.

Stromata culmicolous, nigra, nitentia, levia, leniter tumescentia, dispersa vel subinde confluentia, usque ad 5 x 2 mm., elliptica; clypeus in epidermidem et parenchymam, subopace atrobrunneus, parenchymaticus, usque ad 600 µ alt. et perithecia includens; extus in hyphis dilute brunneis vel subhyalinis, ramosis, septatis, dissolvens. Perithecia immersa, ampullacea, usque ad 330 µ diam., collo apicali usque ad 200 µ long. et 90 µ diam.; paries perithecii hyalinus, circa 10 µ cr., concentrice fibrosus, ex cellulis angulosis, fortiter compressibus compositus. Asci numerosi, erecti vel sursum convergentes, cylindracei, apice rotundati, breviter stipitati, 4-(8)-spore, 120-140 x 10-11 µ. Sporae oblique 1-seriatae, ellipsoideae, hyalinae, continuae, leves, 22-26 x 7.5-9.5 µ. Paraphyses numerosae, filiformes, hyalinae, 1-2 µ cr., ascos aequantes, dubiter septatae, sursum subinde furcatae.

Hab. in culmos Cladii glomerati, Auckland, New Zealand, Dingley in DSIR 17245.