Russian ground forces have 280k soldiers.
Any army has a large proportion of teeth-to-tail i.e. you have training troops, home logistics, base security, troops that are critical elsewhere, etc...
The US could not field 190k/280k front line troops. Russia may tend to privilege front line power compared to logistics, but nevertheless those 190k troops must represent most of their available troops, minus calling up conscript reservists.
40k casualties? Possible, seems high, but who knows, really. Thing is, that level of attrition, even on a highly motivated army, would really start to hit morale and combat effectiveness. Troops almost never fight to the last man.
The Russian army is carrying out a war they weren't told to be expecting, for unclear reasons, and they are attacking rather than defending their home territory.
That level of loss, if it is really taking place, must be impacting their direct combat capability to a very high extent. Troops manning artillery or in entrenched positions would be less affected, but offensive operations would be hard to keep up.
Note also that this effect applies regardless of which forces constitute those 190k. If they include National Guard units then those units are also degraded. Or airborne, or whatever. What's left is not the pure numbers obtained by subtracting the losses from the initial forces.
The 190k do include soldiers from other branches, such as the air force or the navy ships operating in the Black Sea. Still, there can't be too much gas left in the tank at this point.
Extra branches
The National Guard: 340k
But I don't think they are that comparable to say the US National Guard, as they include things like riot police and crowd control. As a whole, they don't seem necessarily equipped, trained or motivated to operate in combat operation, though they could take over security in controlled areas. They're also Putin's personal guard in some ways so their use abroad also takes them away from home, managing protesters for example.
Russian Marine Infantry: 12k
There was a question about Russian Marines on SE.History IIRC and why they were so much smaller than their US counterpart. They're not going to move the needle all that much either.
Airborne: 45k
Special forces : listed by wiki as classified
Spetsnaz, an umbrella term for special forces, but a subset of the branch above, is estimated as at most 17k by one resource.
Reservists:
I can't really speculate on what bringing up the conscript reservists would change to the numbers, but some things need to be kept in mind:
- conscripts, especially reservists, are less combat-effective
- they come at a real political cost to Putin, especially as they are legally not supposed to be used abroad. That's true for serving conscripts in any case.
- they are some months away from being usable in Ukraine.
Bottom line - probably most already committed:
150-190k is a huge proportion of what I expect would be available as ground combat troops. I am not saying there is nothing left, but don't make the calculation of 190k/800k (total Russian armed forces) means that Russia is only 25-30% committed.
The US "only" put in 100-ish k into Iraq for example, with a much bigger army (US armed forces were about 1.4M at the time). And look at the paltry numbers the EU aims to get with a rapid reaction force: 60k (2003 numbers).
p.s. to give an idea of KIA vs wounded for the US they are about 1-10.
In the first 6.5 years of Operation Iraqi Freedom (OIF), U.S. military casualties exceeded 3,400 hostile
deaths, 800 nonhostile deaths (due to disease, nonbattle injury, and other causes), and over 31,000 troops wounded in
action.
So the 500 Russian deaths admitted to several weeks back could by themselves easily mean 2000-3000 wounded, of various severity.