DESCRIPTION: Apothecia developing on fallen leaves or dead fern fronds, erumpent from host tissue, arising from small patches of compact, hyaline fungal tissue. Apothecia sessile, base of disc lying flattened against host substrate, up to about 1 mm diam., receptacle with narrow tapering appendages, up to about 1 mm long. Ectal excipulum 2-layered; outer layer confined to lower half of receptacle, comprising textura angularis to textura prismatica with elements oriented at high angle to surface of receptacle, cell walls hyaline (may be encrusted with dark material), thickened, gelatinous; inner layer extending to edge of disc, comprising cylindric to long cylindric cells with walls hyaline (may be encrusted with dark material), thickened, gelatinous. Medullary excipulum comprising cylindric cells with gelatinous walls, cells often oriented perpendicular to surface of host. Excipular hairs arise from outer excipular layer, cylindric, with few, thin septa, walls thick, smooth, hairs tightly aggregated into large, tapering, tooth-like appendages, often dextrinoid in Melzer's reagent. Asci cylindric, wall thickened at apex, apical pore amyloid or not. Ascospores elliptic to fusoid, 0-1-septate, hyaline to pale brown (septate and coloured usually after release from asci), wall smooth, thin.

DIAGNOSIS: Apothecia erumpentia, sessilia, appendicibus pilaceis usque ad 1 mm longas. Excipulum bistratis; stratum exterior limitatum ad basim receptaculi, e textura angularis vel textura prismatica compositus, cellulis depositis ad angulum altum, cellulae parietibus hyalinis, gelatinosis, interdum materia fusca incrustatis; stratum interior cellulis cylindricis vellongi cylindricis, cellulae parietibus hyalinis, gelatinosis. Appendices compositae arctae aggregatae pili cylindrici angusti. Asci J- vel J+; ascosporae ellipticae vel fusiformes, 0-1-septatae, hyalinae vel brunneae dilute.

ETYMOLOGY: hispidus, with coarse, erect hairs or bristles; refers to the macroscopically distinctive excipular appendages comprising aggregated groups of hairs, the diminutive reflecting the sizeof these fungi.
NOTES: This genus has been placed in the Hyaloscyphaceae because of its excipular hairs. Within this family Echinula Graddon is similar in having apothecia ornamented with tooth-like appendages made up of tightly aggregated hairs (Graddon 1977). Echinula is monotypic, the only known species being confined to Rubus leaves in the United Kingdom. The genus differs from the Australasian fungi in having much smaller apothecia (0.1-0.2 mm diam.), and an ectal excipulum comprising a single layer of angular cells with nongelatinous walls (Scotland, Argyll, Isle of Mull, Aros, on Rubus leaves, M. C. Clark, May 1974, Holotype of E. asteriadiformis, K M41270!; England, Warwickshire, Temple Balsall, on Rubus leaves, M. C. Clark, 18 Jul 1971, K M47708!). The excipular hairs do not show the dextrinoid reaction typical of those of the pale Hispidulaspecies. In all Hispidula species with pale excipular appendages, the hairs making up the appendages give a dextrinoid reaction in Melzer's reagent. When the hairs are viewed under an interference contrast light source, the reaction appears amyloid at some angles. The thick-walled, dextrinoid hairs may suggest a relationship between these fungi and genera such as Hyalopeziza, Hyaloscypha, and Unguicularia, several species of which have similar hairs (Huhtinen 1989; Korf & Kohn 1980; Raitviir & Huhtinen 1997). The shape of the excipular cells and their thickened walls is similar to the "textura prismatica incrassata" described by Huhtinen (1989) for some Hyaloscypha spp. However, the orientation of the excipular cells in Hispidula differs, and the very long, aggregated hairs of Hispidula are quite distinct to any species described to date from these other genera. Most Hispidula species have apothecia that are variable in colour, from pale yellowish to dark brown, even in single collections. When the apothecia are dark, the outermost cells of the excipulum are encrusted with yellow-brown material. This encrusting material is soluble in lactic acid. The one species with dark red apothecia has similar encrusting material on the outside of the excipulum, but also has red pigment and red crystallike inclusions in the gelatinous cell walls. This red pigment is soluble in 3% KOH.

TYPE SPECIES: Hispidula pounamu P.R.Johnst.