27-11-2025 15:41
Thomas LæssøeSpores brownish, typically 4-celled; 26.8 x 2.4;
27-11-2025 12:01
Thomas Læssøehttps://svampe.databasen.org/observations/10496727
27-11-2025 11:46
Thomas Læssøehttps://svampe.databasen.org/observations/10493918
27-11-2025 11:31
Thomas LæssøeCollectors notes: Immersed ascomata, erumpent thro
23-09-2025 13:31
Thomas Læssøehttps://svampe.databasen.org/observations/10534623
25-11-2025 14:24
Thomas Læssøehttps://svampe.databasen.org/observations/10490522
26-11-2025 18:13
Jason Karakehian
The entire run of Mycotaxon is now available throu
25-11-2025 11:03
Mick PeerdemanHi all,One of my earliest microscopy attempts, so
Acanthostigmella
Eduard Osieck,
23-04-2015 20:19
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
Björn Wergen,
01-05-2015 00:01
Re : Acanthostigmella
Hi Eduard,
do you still have a piece of this collection for studying?
regards,
björn
do you still have a piece of this collection for studying?
regards,
björn
Eduard Osieck,
01-05-2015 15:23
Re: Acanthostigmella
Hi Björn,
Yes the material is still in good condition, the perithecia have even multiplied over a larger area of the (not dead) Hedera twig. Apparently the ascomata become pale brownish after some time. Some ascomata are larger than indicated, up to 0,10 mm, but still smaller than in Barr's description of A. brevispina. However, I have found also much longer ascii, up to 64-75 um. They seem to stretch outside the perithecia. So it might very well be this species or a yet undescribed European counterpart. Particularly striking is the enlarged median cell ("2e loge sporale nettement renflee", quoted from Holm 1957).
I will send you the material today, than we get at least splendid photos :)
EDuard
Yes the material is still in good condition, the perithecia have even multiplied over a larger area of the (not dead) Hedera twig. Apparently the ascomata become pale brownish after some time. Some ascomata are larger than indicated, up to 0,10 mm, but still smaller than in Barr's description of A. brevispina. However, I have found also much longer ascii, up to 64-75 um. They seem to stretch outside the perithecia. So it might very well be this species or a yet undescribed European counterpart. Particularly striking is the enlarged median cell ("2e loge sporale nettement renflee", quoted from Holm 1957).
I will send you the material today, than we get at least splendid photos :)
EDuard