SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca6fb097d3399ccda1465b293942cc1bb8b1853340d661c3c82cbf1409f165ee' 
  AND token = 'Jc2crf0OVLfklfISsdlwrvq8km76v4EhPurJ8h4IbG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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