SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1cb589ba5f54f3739a38d203cded6cf68b6a9c9e42c7690f9a8a99eee753ffd' 
  AND token = 'JBXlD8Nl+OjIT2mzYCWy9bkAAMA6ShFF2gzDPd/pIww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00059

JSON explain

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