SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '039cb7b28cb72079455386b5aaa80bb0944b25c97a9983681502d3999586f1ae' 
  AND token = 'UiAuC4r4yvOEpZkMXT8pthpEDiWu5IOVmRSaUqAxv6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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