SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9c4b091b56301ffd523cdccfaaa0cd6edd21cc18d500cda824213c3c4866214' 
  AND token = 'nwwBIHGsafDQ8GlfsgUn2sKMy2G7HY6rplHR9VmYdWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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