This is a genus that I have only recently ‘discovered’ which has 25 species listed on FRDBI but more to come! They come in a variety of forms with teleomorph and anomorph stages . Anomorph stage – genus Trichoderma!
One that has been found locally is possibly Hypocrea aureoviridis. On fallen ivy encrusted willow in damp scrub woodland (VC41). 3-4mm roundish yellow ‘pustules’ with brown ‘dots’ . Photos x10 and x60 USB microscope (sorry about quality!). Brian Douglas at Kew has suggested this as a possibility based on initial photo but I think microscope work will be necessary to be certain.
Also found recently in VC41 is possibly H.britdanie only 3 UK records and not on FRDBI. Specimen with Brian at Kew. Superficially seems to appear similar to some Hypocreopsis spp. (well to me!)