SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1797d45daad080b027fb7844302c05f4efb4a8a157febf66d9d070d1a4dc198b' 
  AND token = 'W0DKtPmR3fGpUcDUi/r50XAuV6ZyJwj8vy9UzufNmqg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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