SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5439c09bad7eb66ac45e2b0c5fee6e375ce66ab8ea7a2f9750540eef03894aed' 
  AND token = 'GLggPJ8GEc+G9OMjtQiYmScebFMs2HbwnsGB9XRDYT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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