SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5590cfa7fb1a794cdfa052f40b3ee2bc33ab55bec593a4067a6456551d2ea479' 
  AND token = 'HzLHrOQGaKFheZhOUoGd4LZDbqi2IYj8ww1XbpzQR3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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