SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb0900f5708c31dabdf248e1c3979fb38cad940776e26d7732594cbedf114b19' 
  AND token = 'ICcTMFM5xK4NPrKkjlELZuZlcVwUASZiOkJDxpQXEfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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