What could be causing this leaf curl/discoloration on this red maple?

[Strongbox18]

I have a red Japanese maple that for some reason is putting out strange discolored growth this spring, some of the branches are putting out normal growth others have a strange discolored crinkle to them, curious as to what everyone thinks could be the cause of the issue. Hoping the tree grows out of it with its second flush, this tree usually grows strong. The roots have not been worked on the tree in over a year so I know that is not the issue, I’m guessing some sort of fungal issue. Any input would be great thanks.

 

[Strongbox18]

I have not ruled out verticillium but the leaves appear to be alive and are not dying back, it seems like what appears to be reverse growing leaves is the best way I can describe it.

 

[Strongbox18]

A couple more clear pictures

 

[pandacular]

I can't provide much insight into what might be causing this, BUT I do know some of the info that might be helpful to those that can.

1) What is the soil for this tree? Providing a picture and description may help
2) Has there been any recent work done to the tree? wiring, pruning, repotting, etc
3) When was the tree last repotted?
4) What is the watering regimen like?
5) What sort of sunglight conditions do you have it in?
6) Where are the struggling branches relative to the healthy ones?

 

[Shibui]

Hard to be certain just from online pics but I've had similar deformed leaves in spring, usually on tridents. The good news is that it does not appear to be fatal and usually disappears later in spring.
Down here there's debate about what causes it. Theories range from bugs/mites/etc feeding on the buds before the leaves open to fungal cause. Some use fungicide and report subsequent growth is normal. Those that treat with pesticide also report that subsequent growth is normal. I just studiously ignored the problem and subsequent leaf growth returned to normal. Make of that what you will.

My advice is to keep an eye on progress.

 

[Strongbox18]

Thank you both for the replies,

Planted in standard bonsai mix, (mainly akadama and lava rock)

No recent work has been done, two strong sacrificial branches were cut back in February and sealed at the time. New buds pushing from cut sites.

Tree was last repotted over a year ago, no root work has been done in over a year.

I water this tree regularly with all of my other maples.

Tree gets morning sun until the afternoon, totally covered from the elements under a opaque plastic roofing material with shade cloth. We did get a random cold snap about a week ago but this tree was totally covered and could not see that causing the issue as the leaves are not crispy at all.

The image shows both healthy and deformed growth in the same branch. So it is not confined to one area of the tree.