Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20e4a4c1a534537e305e206e170c110c4cff5ff50528f677dd44ed29f3fe15a4' 
  AND token = 'uHT9HWqqExsSKRhzs0ogMh2XaiFt2sQyhdUMKjkPaCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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