SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8172b5a69bf2f566e8487d227ac6f2225f9f4658d9cb3ac3e94cb4c07c9c64f1' 
  AND token = 'TN8FT2ItZVtL7zdAjEbVNHzpbm8U9BlQmns3mmPdPEE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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