SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be2d06b9642eab30dd40557536382cd3367490b1ded4b0d2f2c56afc6f7af4a8' 
  AND token = 'V35CNoLX1ACIO9cL59GQ2F3RjzmJAH91N49jr6Y/dX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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