SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f790b23bf1c959901c8e92dc1328a90434fb1dfe1a7d17f3bef972f0c3bccd7' 
  AND token = 'J5eNo9TwofJU9WFRWjodgBnTTCh/mHf1lnms7IfVqvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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