SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af06f6f4ef86a8c344628af68ab804eb9bd4dc2dc87f512bffcd9b79aa278734' 
  AND token = 'ToIJE7bQmMHpJLyAz7Q9toti2SRbrtGAaWKNyxCUC3U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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