SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f529cfe97ce7d200c1ba13ffd1d3844c3ca29d41b0f7885165911a64caf4d340' 
  AND token = 'liKzNT1n2ZiYXtvhgbzoYV5Dp6fMK9DFx6K/kH3C7BI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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