SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9c8b5e8a4647e3499ebe01958c94b6a2828af9a978ea48f55ac955c236f5101' 
  AND token = 'iljayCqCgKtBCxZsOIol3oV8JwVZJUprwIl5Y+FF9/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}