SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '21c90c234793414b50a6b25509e7deb7f518872132e02c17869f2c4df5586784' 
  AND token = '2WfSwyjz+pA9a0QPwAU2jJ3/Zs+NBPyS+vExRGdaTGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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