Wednesday 1 June 2011

#55 Austroboletus lacunosus

Finally some soaking rain in the Hunter Valley, and the fungus season is upon us. I found three new Boletes, one of which I was able to identify without too much trouble - Austroboletus lacunosus (formerly known as Austroboletus cookei), but it doesn't appear to have a common name.

The most distinctive feature of this fungus (and other species of Austroboletus) is the stem which is patterned with haphazard depressions separated by a maze of stringy-textured ridges. The stem is dry and has no ring, is positioned either central or off-centre, with a deep circular depression jutting into the fertile pored service.

Pore openings are large, up to 1mm, starting out pure white, turning pale pinkish brown, and aging to ochre. Spore print is pale pinkish brown. I didn't find any evidence of infestation by insect larva in any of the three specimens I examined.

Cap is convex, generally pale brown, dry and swede-like in texture (can be slippery when young and wet), and up to 150mm diameter. Tissue remnants often form a 'frill' around the rim of the cap. This mycorrhizal fungus occurs in the soil of mixed forests in eastern Australia, and New Zealand. My observations so far indicate that this fungus occurs singly.

Slightly slimy wet cap of fresh fruit body. The stem was about 130mm high


Dry cap, bulging pale pink pored undersurface

White pore surface on young specimen - notice the 'frill' around rim of cap

And notice the deep depression around the top of the stem

White flesh that does not bruise or change colour - deep pore tubes, and off-centre stem

White mycelium

A short off-centre stem on this example. Notice the right-hand side of the fungus is infected with a mould or fungus. Also notice the yellowing of the base of the stem that sometimes occurs


My sightings of Austroboletus lacunosus

[This will be updated with new sightings]

Brunkerville, NSW - mixed forest May 2011

7 comments:

Ken Beath said...

Didn't realise there were two Austroboletus sp. Nice find.

Gaye said...

Hello Ken,

there are actually more than two species of Austroboletus in Australia, but this is the first I have found. Naturally I was thrilled.

Regards,
Gaye

Ken said...

I've seen A. niveus, of all places next to a rock in themiddle of a walking track.

Gaye said...

That was a lucky find, Ken, and that's the way it happens so often - some wonderful fungus popping up right in front of us. A. niveus is rather unmistakable, so I hope I stumble upon one soon too.

Cheers,
Gaye

Anna Durkin said...

Thanks to your clear photos I was easily able to easily identify my specimen in Colongra Wetland, Budgewoi. I was not sure from other photos because the network on the stipe (an identifying feature) had worn off. Anna D. 18 Feb 2013

Unknown said...

Just austroboletus lacunosus around mt Vincent, huter valley I think I prefer the name cookie to lacunosus as it remindeds me to a cookie :)

Anonymous said...

there are heaps of these around where i live in the Nimbin hills. are they edible do you think? i hear most boletes are edible but not quite sure about the Australian variety.