SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61a691936752c13d33a4ebdd3cf1970b3fda5c6f7ba426a41fffc363093f840b' 
  AND token = 'fvP6BEPrCPtLhXgU41fds2JkFIc9aW6GpxuZFhKTHdM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}