SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24dd47dcd2498db1c81251506054a722941a2435196257809e8bcfb34fa9d649' 
  AND token = 'wp3Z4ZhPzHQ6IqUwvTpyuHLj7/9fFYpKhB50hAS31Ok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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