SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dfe98b6541adf66a61d934b749b7812efb8ddac4344eb23c13c895ca761c9c4' 
  AND token = 'qSA4aNfKA/oRbcuP2MaEheFqmhn7k3Kfk7SxqKCHJVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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