SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05f7312017227ea30c1ffb552dc1eb31bbfff50f459df3b3033c89f30542a475' 
  AND token = 'MIs4PAW5DpGualB/sSjTZrzR/6IUluQJSRDCvzHHfJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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