This post is part of an ongoing series. You can read the introductory post here.
Clavulinopsis luteoalba ~ Apricot Club
ID difficulty rating: ⭐⭐⭐
I’ve been out with field mycologists more experienced than myself who’ve been confident identifying this species in the field. But I’m always a bit unsure with these yellow- / apricot- coloured club things, so I’ve given it a ‘⭐⭐⭐’ difficulty rating. Checking the spore shape under the microscope helps to confirm the ID of this common and widespread species.
Working through the key in ‘I FUNGHI CLAVARIOIDI in Italia’ by Paolo Franchi & Mauro Marchetti (2021), it’s the spore shape and the size of the apiculus (the pointy bit of the spore which attaches to the sterigmata at the end of a basidium) which distinguishes this species from similar-looking yellow-orange club fungi.
I got a good look at a basidum here:
![](https://substackcdn.com/image/fetch/w_1456,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F9c8f210e-1bcf-4605-a804-872b2e369ae0_1600x1200.png)
Here’s what the smooth, almond-shaped spores look like:
I haven’t got the apiculus of any of these spores in focus, but you can see it’s not particularly long / obvious. I measured the spores as being 6.5-8.0 x 3.0-4.0 microns, which is the right ball-park for Clavulinopsis luteoalba.
Here’s a side-by-side comparison of two yellow- / apricot- coloured club things I collected today. On the left is the collection I’m currently discussing - Clavulinopsis luteoalba - and on the right is a collection of Clavulinopsis helvola which I confirmed through checking the spore shape.
They do look very different when you look at them side-by-side, so I wonder if I’ll have more confidence identifying them, next time I encounter them in the field?