Hello all,

Minute hyaline perithecia (0.05-0.06 mm) with hyaline setae (20-23 um).
Bitunicate asci (30-40 x 10 mu) with 3-septate hyaline spores with big guttules: 13-16 x 4-5 um. One median cell larger than the other.
Substrate: Lophiotrema cf. neohysterioides (= curreyi) and on bark of Hedera.

I assume this belongs to the genus Acanthostigmella.
With the key included in the paper of Barr 1977 it easily keys out as A. pallida but this species has much smaller spores (7-10 X 2.5-3.5 um) and smaller ascii (20-25 x 10-11 um).
Six years later (Barr & Rogerson 1983) described A. brevispina (also known as Tubeufia brevispina) as a new species with spores which are more in agreement with my find: 14-18 x 4-5 um. However this species has larger ascii (50-60 mu) and also much larger perithecia (diameter 0.13-0.18 mm).

Belongs this find to Acanthostigmella? And what about the species?

I hope somebody has some knowledge about this species although the Ascofrance database does not contain any finds.

Eduard